As promised, here's what I learned from my entrepreneurship class last quarter:
First off, Sindrian Arts, at least my current vision of it, is what is know as a 'lifestyle' startup, as opposed to a 'foundation' or 'gazelle' startup. A foundation startup is like an inventor's project, but on a larger scale: the entire business is centered around the research and development of a new idea which is then sold to another firm to utilize. My class did not spend much time on these, focusing more on gazelle startups. Gazelles are more like what most people think of when they think of startups: it's designed to grow as much as possible as quickly as possible so that it can be sold for a huge profit a few years down the line. These are the types of business venture capitalists like to invest in. Lifestyle startups, on the other hand, could be seen as the gazelle's little cousin. They tend to be much less ambitious, focusing more on creating a stable small business then a national firm with explosive growth. As I mentioned before, the current version of the Sindiran Arts business plan has two distinct phases, and the first phase falls into the lifestyle category.
See, the mission of Sindrian Arts is to help create a new manufacturing paradigm based upon (among other things) decentralization. I want to help create a community of small, local businesses that collectively compete with big-box stores. The first phase of this is to create a model for success, so I need to create a living laboratory for my ideas. Since the end goal is to help create lots of small business, this laboratory will be a small business itself. Once I've refined and proven my ideas, I can then move on to the second phase of the business where I become an evangelical consultant to help others create the same kind of business.
Now, this is what I learned: most people are not interested in investing in lifestyle startups. This is one of the reasons I didn't write the Sindrian Arts business plan for the class: the class was geared towards writing business plans that would be attractive to investors. This also tells me that when I start looking for seed money, VCs are NOT where I should look. In looking at alternate sources of funding I came across Kickstarter. Through Kickstarter, I could raise the right amount of money with very few strings attached. Not only that, but there have been other CNC-based projects on there that have been very successful. Sounds like a good match!
Sunday, March 27, 2011
Wednesday, March 23, 2011
And now we get down to business
Apologies for not having posted in a while; unsurprisingly, school kept me busy. However, not a whole lot of consequence happened, so here's the cliff notes for the interesting bits:
Classes I took:
Design communication:
Same as every quarter; sketch a lot, do some renders. One highlight is that I was introduced to Prezi, a wonderful little presentation web app that allows anyone to make a visually interesting presentation fairly easily.
JCPenny bag studio:
This was my design studio for the quarter. Our task was to re-design JCPenny's (or maybe it should be jcp's) approach to reusable bags to help them transition away from plastic bags. Unfortunately it was a group project, and the groups kept changing. However, the execs from jcp LOVED the final presentation, so it all worked out in the end.
Design Seminar:
The purpose of this class was to prepare a proposal for our capstone project, start on research for it, and get it approved by the faculty. Given that I already had a pretty well fleshed-out vision of my capstone (the CNC-based business I just spent a quarter working on), this was pretty easy.
Career Development:
AKA, how to get a job after you graduate. Since I plan on being self-employed, I had to work with the professor to adapt the assignments to suit my needs, but it worked out all right. For the most part, I simply adapted work from my final class:
Entrepreneurship:
This was my big class of the quarter. Ironically, it was also my only elective, and the only class I took outside of the design college. I cannot rant and rave enough about this class; it was hands down the best thing I took at UC to date. If you go to UC and are at all interested in entrepreneurship, I HIGHLY recommend you take this class (or any class, really) taught by Tom Dalziel. If you're not in the college of business you'll have to get special permission, but Tom will be very happy to have you.
This was the first class I've ever taken with NO BUSY WORK. Every single assignment was part of the larger process of developing a business plan to be presented at the end of the quarter.
I had originally planned to write the Sindrian Arts business plan for this class, but as did more research, I realized that a: the business I wanted to start would not be attractive to outside investors interested primarily in making money, and b: my business actually had two distinct phases, each requiring their own plan, and thus too much work for the class. What I ended up doing was writing a business plan for a version of Sindrian Arts.
In this business, called Green Furniture Works, the focus would be on making sustainable designer furniture. While not quite what I want to do, it was close enough that I could still lean a lot from it, while being much more applicable to the class. My next post will be about how this all has informed where I'm going from here.
Classes I took:
Design communication:
Same as every quarter; sketch a lot, do some renders. One highlight is that I was introduced to Prezi, a wonderful little presentation web app that allows anyone to make a visually interesting presentation fairly easily.
JCPenny bag studio:
This was my design studio for the quarter. Our task was to re-design JCPenny's (or maybe it should be jcp's) approach to reusable bags to help them transition away from plastic bags. Unfortunately it was a group project, and the groups kept changing. However, the execs from jcp LOVED the final presentation, so it all worked out in the end.
Design Seminar:
The purpose of this class was to prepare a proposal for our capstone project, start on research for it, and get it approved by the faculty. Given that I already had a pretty well fleshed-out vision of my capstone (the CNC-based business I just spent a quarter working on), this was pretty easy.
Career Development:
AKA, how to get a job after you graduate. Since I plan on being self-employed, I had to work with the professor to adapt the assignments to suit my needs, but it worked out all right. For the most part, I simply adapted work from my final class:
Entrepreneurship:
This was my big class of the quarter. Ironically, it was also my only elective, and the only class I took outside of the design college. I cannot rant and rave enough about this class; it was hands down the best thing I took at UC to date. If you go to UC and are at all interested in entrepreneurship, I HIGHLY recommend you take this class (or any class, really) taught by Tom Dalziel. If you're not in the college of business you'll have to get special permission, but Tom will be very happy to have you.
This was the first class I've ever taken with NO BUSY WORK. Every single assignment was part of the larger process of developing a business plan to be presented at the end of the quarter.
I had originally planned to write the Sindrian Arts business plan for this class, but as did more research, I realized that a: the business I wanted to start would not be attractive to outside investors interested primarily in making money, and b: my business actually had two distinct phases, each requiring their own plan, and thus too much work for the class. What I ended up doing was writing a business plan for a version of Sindrian Arts.
In this business, called Green Furniture Works, the focus would be on making sustainable designer furniture. While not quite what I want to do, it was close enough that I could still lean a lot from it, while being much more applicable to the class. My next post will be about how this all has informed where I'm going from here.
Monday, February 7, 2011
Catch-up, part the first
Apologies for lapse in posts, but between wrapping things up in Boston, moving back to Cincinnati, starting classes back at DAAP, and being really sick twice, I've forgotten to make time to post here. However, I've recently decided to get my act together, and part of that is going to be posting here at least once a week.
Here's what's happened since my last post:
That standing computer desk I was working on turned out beautifully:
Leaving out a bit of trouble-shooting, it only took 45 minutes to mill all the parts, and that's with multiple passes. With a more ridged machine, I could easily half that. Design-wise, it was a little wobbly, but I think I know a neat way to fix that with a few eye bolts and some rope or cable. Also, I discovered that it should probably be a bit shorter, since one girl I showed it to said she had a hard time seeing the screen.
After that, I made a few modifications to the Blackfoot pattern to integrate the additional bearing holders for the X axis drive shafts and to eliminate the parts I wouldn't need before making the g-code for cutting it. By the time I was actually ready to run the code I was running short on time, so I ran it a little faster that I probably should have. The pieces came out with a few defects here and there, but nothing that would prevent them from fitting together correctly. The next day I packed up all my stuff, and left the morning after that. Thus ended my wonderful travel quarter. I was sad that I didn't get a chance to say goodbye to a lot of the folks at the Asylum, but I'll be back.
Ok, I've got to go grab some lunch. I'll post the rest either later today, or in a day or two.
Here's what's happened since my last post:
That standing computer desk I was working on turned out beautifully:
Leaving out a bit of trouble-shooting, it only took 45 minutes to mill all the parts, and that's with multiple passes. With a more ridged machine, I could easily half that. Design-wise, it was a little wobbly, but I think I know a neat way to fix that with a few eye bolts and some rope or cable. Also, I discovered that it should probably be a bit shorter, since one girl I showed it to said she had a hard time seeing the screen.
After that, I made a few modifications to the Blackfoot pattern to integrate the additional bearing holders for the X axis drive shafts and to eliminate the parts I wouldn't need before making the g-code for cutting it. By the time I was actually ready to run the code I was running short on time, so I ran it a little faster that I probably should have. The pieces came out with a few defects here and there, but nothing that would prevent them from fitting together correctly. The next day I packed up all my stuff, and left the morning after that. Thus ended my wonderful travel quarter. I was sad that I didn't get a chance to say goodbye to a lot of the folks at the Asylum, but I'll be back.
Ok, I've got to go grab some lunch. I'll post the rest either later today, or in a day or two.
Tuesday, December 14, 2010
That's just silly.
Yesterday was a comedy of errors. The day started well enough with some test cuts of small pieces to test slot clearances, and all went well. Then I decided to mill out something big: the standing computer desk:
Now, while for the most part it fits together without hardware, the adjustable keyboard rack does require the drilling of the holes. After figuring out how to get poor 'ol CamBam (free version) to drill holes (and testing this), I started the program.
It started out ok, but then by the third hole it started generating a good deal of smoke. It took lots of experimenting with feed rates, pecking, and other such stuff to figure out what was going on: I was trying to drill holes with a downcut bit.
For the non-machinists out there, allow me to explain: your standard drill bit is what's called an upcut bit, that is the spiral flutes of the bit will bring chips up to the top of the bit. This is good for high-speed cutting, where you have to worry about keeping the bit clear. However, the drawback to using upcut bits in a CNC router is that it will cause the face of your material to chip and break near the cut, especially if you're working on a laminate material like plywood. For this reason I bought downcut bits, where the flutes of the bit spiral the other way. This eliminates chipping on the face, but has other drawbacks, such as not being good at drilling holes. What was happening to me is that the MDF dust created by the bit was being kept down in the hole where it was compressed and rubbed against itself a high speed, causing it to burn. To fix this, I changed the program so that I'd only drill shallow holes, the plan being to take the pieces over to the drill press and finish them after they were cut out.
Just before I was going to start cutting the actual pieces out, suddenly everything shut off. Turns out someone in the wood shop next to me blew a fuse. To avoid this in the future I used an extension cord to plug into a different outlet. I thought nothing of this at the time, but it would haunt me the rest of the night. After that I could not get the machine to do what I wanted. It wouldn't always move when it was told, and nothing I did or changed seemed to help. At 11pm I decided to call it a night and went home.
I came in this morning and after implementing a clamping system I thought up to keep the workpiece from moving (we thought that perhaps this was causing some of the error), I got back to work.
As one would imagine, the same problem was still there, but this time I noticed that it seemed to be limited to the Y and Z motors. I checked the connections, moved cords around to avoid possible interference (even though they were shielded), but no dice. The most annoying thing was that it would work fine until I actually went to run a program. A stroke of luck finally showed me what was going on: I turned the router on and had the program start and then when I saw it was moving I turned on the shop vac. I look back to see that the Y motor had stopped moving right when I had hit the vac's switch. Remember when I changed outlets? Turns out the new one didn't supply the same amount of current as the old one, so the motors weren't getting enough juice when the router and vac were on as well.
They're now on a different circuit. Off to cutting!
Now, while for the most part it fits together without hardware, the adjustable keyboard rack does require the drilling of the holes. After figuring out how to get poor 'ol CamBam (free version) to drill holes (and testing this), I started the program.
It started out ok, but then by the third hole it started generating a good deal of smoke. It took lots of experimenting with feed rates, pecking, and other such stuff to figure out what was going on: I was trying to drill holes with a downcut bit.
For the non-machinists out there, allow me to explain: your standard drill bit is what's called an upcut bit, that is the spiral flutes of the bit will bring chips up to the top of the bit. This is good for high-speed cutting, where you have to worry about keeping the bit clear. However, the drawback to using upcut bits in a CNC router is that it will cause the face of your material to chip and break near the cut, especially if you're working on a laminate material like plywood. For this reason I bought downcut bits, where the flutes of the bit spiral the other way. This eliminates chipping on the face, but has other drawbacks, such as not being good at drilling holes. What was happening to me is that the MDF dust created by the bit was being kept down in the hole where it was compressed and rubbed against itself a high speed, causing it to burn. To fix this, I changed the program so that I'd only drill shallow holes, the plan being to take the pieces over to the drill press and finish them after they were cut out.
Just before I was going to start cutting the actual pieces out, suddenly everything shut off. Turns out someone in the wood shop next to me blew a fuse. To avoid this in the future I used an extension cord to plug into a different outlet. I thought nothing of this at the time, but it would haunt me the rest of the night. After that I could not get the machine to do what I wanted. It wouldn't always move when it was told, and nothing I did or changed seemed to help. At 11pm I decided to call it a night and went home.
I came in this morning and after implementing a clamping system I thought up to keep the workpiece from moving (we thought that perhaps this was causing some of the error), I got back to work.
As one would imagine, the same problem was still there, but this time I noticed that it seemed to be limited to the Y and Z motors. I checked the connections, moved cords around to avoid possible interference (even though they were shielded), but no dice. The most annoying thing was that it would work fine until I actually went to run a program. A stroke of luck finally showed me what was going on: I turned the router on and had the program start and then when I saw it was moving I turned on the shop vac. I look back to see that the Y motor had stopped moving right when I had hit the vac's switch. Remember when I changed outlets? Turns out the new one didn't supply the same amount of current as the old one, so the motors weren't getting enough juice when the router and vac were on as well.
They're now on a different circuit. Off to cutting!
Saturday, December 11, 2010
It was a good day
It would seem that after some teasing, Murphy decided to give me a break yesterday.
First, the motors arrived right when UPS said they would. Installing one on the x axis went smoothly, but I ran into some problems once I started testing and tuning it. First, when I tried to run it it kept stopping at the same place on the table and clutching out. Turns out the set screw that was keeping one of the drive sprockets in place had loosened somewhat and was catching on the chain. For some reason it now wanted to be tighter than it had been before, which meant grinding a new flat into it's head to prevent further catching. Once that problem was solved I started the process of finding the right amount of current to drive the motor. Surprisingly, even with the current turned all the way up to 4.3A (the motor should only get 3A), it was still not able to move at the speeds I thought it should. In looking for a cause of this, I had the first of the day's breakthroughs.
It turns out the dip switches are "on" when they are in the down position. This meant two things: that the auto half current function (which helps keep motors from overheating) was off when I thought it was on, and that the boards were set to microstep at 25 subdivisions instead of just 5. While microstepping does give you much more precision (which I don't really need), it also severely reduces the amount of torque (which I do). I turn the auto half current function, set the driver to 2 subdivisions just to be on the safe side, modify the necessary settings in the software to reflect this, and resume testing.
The torque of the motor improves significantly, but it's still not performing as well as I'd expected. I could get it up to about 9 inches per second, but higher than that and it would choke, regardless of current. Now, when I was running my previous jobs, I had the machine running at feed rates of 50 and 100, so I was understandably concerned. I had no idea what was wrong, and was starting to get very frustrated.
Then it hit me: the units are different.
See, those feed rates of 50 and 100 were inches per minute, not second, so what I thought was a slow 9 was in fact 540 IPM, way faster than I'd ever need to go.
It's amazing how one small realization can improves one outlook on life.
After that, it was all cake. I re-tuned all three motors and cut the next prototype of the card dispenser. The y axis motor got a little on the warm side, so I had to let it rest half-way through the job, but I can turn the current down on that one with torque to spare.
There were some issues with the card dispenser job itself, but that was because of how I had it cut, not any hardware problems. I assembled it today, and it works quite well:
You can find other pics of it, along with screenshots of other things I've modeled in Solidworks that are destined to be milled out on a CNC here.
First, the motors arrived right when UPS said they would. Installing one on the x axis went smoothly, but I ran into some problems once I started testing and tuning it. First, when I tried to run it it kept stopping at the same place on the table and clutching out. Turns out the set screw that was keeping one of the drive sprockets in place had loosened somewhat and was catching on the chain. For some reason it now wanted to be tighter than it had been before, which meant grinding a new flat into it's head to prevent further catching. Once that problem was solved I started the process of finding the right amount of current to drive the motor. Surprisingly, even with the current turned all the way up to 4.3A (the motor should only get 3A), it was still not able to move at the speeds I thought it should. In looking for a cause of this, I had the first of the day's breakthroughs.
It turns out the dip switches are "on" when they are in the down position. This meant two things: that the auto half current function (which helps keep motors from overheating) was off when I thought it was on, and that the boards were set to microstep at 25 subdivisions instead of just 5. While microstepping does give you much more precision (which I don't really need), it also severely reduces the amount of torque (which I do). I turn the auto half current function, set the driver to 2 subdivisions just to be on the safe side, modify the necessary settings in the software to reflect this, and resume testing.
The torque of the motor improves significantly, but it's still not performing as well as I'd expected. I could get it up to about 9 inches per second, but higher than that and it would choke, regardless of current. Now, when I was running my previous jobs, I had the machine running at feed rates of 50 and 100, so I was understandably concerned. I had no idea what was wrong, and was starting to get very frustrated.
Then it hit me: the units are different.
See, those feed rates of 50 and 100 were inches per minute, not second, so what I thought was a slow 9 was in fact 540 IPM, way faster than I'd ever need to go.
It's amazing how one small realization can improves one outlook on life.
After that, it was all cake. I re-tuned all three motors and cut the next prototype of the card dispenser. The y axis motor got a little on the warm side, so I had to let it rest half-way through the job, but I can turn the current down on that one with torque to spare.
There were some issues with the card dispenser job itself, but that was because of how I had it cut, not any hardware problems. I assembled it today, and it works quite well:
You can find other pics of it, along with screenshots of other things I've modeled in Solidworks that are destined to be milled out on a CNC here.
Monday, December 6, 2010
More shopping
I had to order two new motors today. One to replace the z axis motor that got too hot the other day, and one to replace the x axis motor that got too hot today. Not sure exactly why, since I thought the current was turned down on that one, but perhaps not. The CNC is again out of commission until the motors arrive, which with any luck should be before the weekend.
*sigh*
Ah well, time to do some more CAD modeling. I'll have plenty to mill once it's up and running again.
*sigh*
Ah well, time to do some more CAD modeling. I'll have plenty to mill once it's up and running again.
Sunday, December 5, 2010
First prototype!
A quick update today:
On Friday I milled out parts for a prototype business card dispenser. Check out the flickr set here.
On Friday I milled out parts for a prototype business card dispenser. Check out the flickr set here.
Thursday, December 2, 2010
Two steps forward...
Yeah, damn clichés.
Yesterday, as you all saw, the machine was up and running. However, by the time I left it was once again non-functional. I'm pretty sure what happend was that the current was turned up to high on the z axis motor, causing it to overheat and eventually burn out. Usually I keep an eye on motor temp using an infrared thermometer, but it's batteries died. Thankfully my good friend Calvin had a small stepper I could borrow until I make sure the other motor is dead, or it gets fixed. I picked it up from him this morning, and that was one problem licked.
Another issue I had yesterday was that while the machine did work, it was painfully slow; that one part took around 45 minutes to mill out. This was because the router I was using could only spin at 500 RPMs, which meant I could only make the machine move at six inches per minute. I can't afford to spend that much time waiting, so I decided to bite the bullet and buy a bigger router. A wood working supply store near where I live happened to cary exactly what I needed: a replacement motor for a Porter Cable 3 1/4 hp router. Of course, about an hour after I bought it I get an email from my friend Jeff telling me that he has a mailer from that same store that's advertising a replacement router motor for $30 less than what I paid, plus a $25 gift certificate. I call the place back, and they told me that if I come back on Saturday (when that sale starts) with just the receipt, I can get the discount and the gift certificate. Two problems licked.
I get to the Asylum, rebuild the z gantry using the parts designed to hold the larger router, slap it back on the machine, wire in the new motor, install that, and start testing.
The new motor won't drive the gantry. Instead it just clutches out. No worries, the current is probably turned down too low, all I need to do is turn it back up until it has enough power. After much headache, I realize that the potentiometer on the driver board that is used to adjust the current is ever so slightly broken, so that the board doesn't work unless a slight pressure is applied to the dial. A small screw and some electrical tape later, and I've MacGuyvered it back to working condition. Third problem licked.
Now that it's all working again, I'm calling it a day. We'll see what happens tomorrow.
Yesterday, as you all saw, the machine was up and running. However, by the time I left it was once again non-functional. I'm pretty sure what happend was that the current was turned up to high on the z axis motor, causing it to overheat and eventually burn out. Usually I keep an eye on motor temp using an infrared thermometer, but it's batteries died. Thankfully my good friend Calvin had a small stepper I could borrow until I make sure the other motor is dead, or it gets fixed. I picked it up from him this morning, and that was one problem licked.
Another issue I had yesterday was that while the machine did work, it was painfully slow; that one part took around 45 minutes to mill out. This was because the router I was using could only spin at 500 RPMs, which meant I could only make the machine move at six inches per minute. I can't afford to spend that much time waiting, so I decided to bite the bullet and buy a bigger router. A wood working supply store near where I live happened to cary exactly what I needed: a replacement motor for a Porter Cable 3 1/4 hp router. Of course, about an hour after I bought it I get an email from my friend Jeff telling me that he has a mailer from that same store that's advertising a replacement router motor for $30 less than what I paid, plus a $25 gift certificate. I call the place back, and they told me that if I come back on Saturday (when that sale starts) with just the receipt, I can get the discount and the gift certificate. Two problems licked.
I get to the Asylum, rebuild the z gantry using the parts designed to hold the larger router, slap it back on the machine, wire in the new motor, install that, and start testing.
The new motor won't drive the gantry. Instead it just clutches out. No worries, the current is probably turned down too low, all I need to do is turn it back up until it has enough power. After much headache, I realize that the potentiometer on the driver board that is used to adjust the current is ever so slightly broken, so that the board doesn't work unless a slight pressure is applied to the dial. A small screw and some electrical tape later, and I've MacGuyvered it back to working condition. Third problem licked.
Now that it's all working again, I'm calling it a day. We'll see what happens tomorrow.
Wednesday, December 1, 2010
It Made a Thing!
Look!
My CNC made a thing!
It's a replacement for part of the vacuum attachment that was originally milled upside-down. As you can see here, the lobed part that hangs beneath the router has a channel that connects the two openings. That channel is supposed to face downwards, but if you flip the part the bolt holes don't line up. To fix this, I simply milled out another copy of the part and used the current piece as a guide for drilling the holes.
Much better!
My CNC made a thing!
It's a replacement for part of the vacuum attachment that was originally milled upside-down. As you can see here, the lobed part that hangs beneath the router has a channel that connects the two openings. That channel is supposed to face downwards, but if you flip the part the bolt holes don't line up. To fix this, I simply milled out another copy of the part and used the current piece as a guide for drilling the holes.
Much better!
Tuesday, November 30, 2010
It's Ready!
Finally!
My CNC gantry router is finally ready to start making stuff! I'm sure I'll still do a lot of tweaking as I go along, but tomorrow I'll actually be able to start making things.
First order of business will be to go back to Atlantic Carbide to talk to their Onsrud rep, who apparently is only there between 6 am and 2 pm. I need to find out what the best bit for cutting masonite hardboard, which I plan to use in my first project: a business card dispenser. I've already done the CAD modeling and part layout; now all I need to do is to write the g-code. I should have a prototype to show off tomorrow!
My CNC gantry router is finally ready to start making stuff! I'm sure I'll still do a lot of tweaking as I go along, but tomorrow I'll actually be able to start making things.
First order of business will be to go back to Atlantic Carbide to talk to their Onsrud rep, who apparently is only there between 6 am and 2 pm. I need to find out what the best bit for cutting masonite hardboard, which I plan to use in my first project: a business card dispenser. I've already done the CAD modeling and part layout; now all I need to do is to write the g-code. I should have a prototype to show off tomorrow!
I had to go and brag about it
So what happens when you go and say that something will be finished on a certain day? Murphy shows his ugly head.
Damn you, Murphy.
See, everything was ready. I had bought an extension hose for the shop vac, and onsrud cutters for the router. I had even done testing! Apparently, I hadn't done enough. Here's what happened:
I got the new motor wired up to one of my cables, poped it on the y axis (it had a longer drive shaft than my other motors, so it fit better there), connected everything, and loaded up the config wizard to make sure my settings were right. X and y axises still worked fine (so the new motor was good), but when I tried to test the z axis, nothing happened. I called someone over to listen to the motor while I tried to drive it, and apparently it would make a faint humming noise, but that was it. I disconnected it from the z axis lead screw, and it still didn't move. Out came the multi-meter. The cable was good. The port on the electronics box was good. I tested the motor on a different stepper driver board and it worked just fine, so it wasn't the motor. This leaves (as far as I know) only one thing that could be failing to work: the z axis stepper driver board.
Some good news: The guy who built the electronics is going to be here soon, he should be able to accurately diagnose the problem. With any luck, it's something silly I didn't know about, and he'll fix it. Also, I have an extra driver board that only needs very minor repairs to be fully functional, so even if the current z axis board is busted, we've got a replacement; no waiting for shipping.
Wish me luck!
Damn you, Murphy.
See, everything was ready. I had bought an extension hose for the shop vac, and onsrud cutters for the router. I had even done testing! Apparently, I hadn't done enough. Here's what happened:
I got the new motor wired up to one of my cables, poped it on the y axis (it had a longer drive shaft than my other motors, so it fit better there), connected everything, and loaded up the config wizard to make sure my settings were right. X and y axises still worked fine (so the new motor was good), but when I tried to test the z axis, nothing happened. I called someone over to listen to the motor while I tried to drive it, and apparently it would make a faint humming noise, but that was it. I disconnected it from the z axis lead screw, and it still didn't move. Out came the multi-meter. The cable was good. The port on the electronics box was good. I tested the motor on a different stepper driver board and it worked just fine, so it wasn't the motor. This leaves (as far as I know) only one thing that could be failing to work: the z axis stepper driver board.
Some good news: The guy who built the electronics is going to be here soon, he should be able to accurately diagnose the problem. With any luck, it's something silly I didn't know about, and he'll fix it. Also, I have an extra driver board that only needs very minor repairs to be fully functional, so even if the current z axis board is busted, we've got a replacement; no waiting for shipping.
Wish me luck!
Today it will be COMPLETE!!
The replacement motor has just arrived! After I finish this post I'm off to buy some Onsrud cutters for the router and an extension hose for the shop vac, I'll slap the new motor on the z axis, and I'll be OFF AND MILLING!!!
It's about damn time.
Over the weekend I did some testing and tuning using only the x and y axises and a sharpie mounted in the router.
As you can see, with the first run (at the bottom), it started off pretty good, but as it progressed the x axis kept slipping. The problem was that since the set screw in the drive sprocket was so small (#8, no head), I couldn't really torque it down tight enough without stripping the socket and/or allen wrench. Thankfully my friend Calvin was around, and offered me a couple socket-headed screws that took a much larger allen wrench, allowing me to apply plenty of torque. While the larger heads did rub the chain, a little quick grinding with my dremel took care of that. As you can see, the final test showed no slippage at all.
Another mod I implemented at the suggestion of others was the addition of two brackets to help support the x axis drive shafts:
We had noticed that when the drive chains were tightened, it would cause the 1/4" drive shafts to flex. To counteract this, Jeff designed and milled out several pieces of MDF to hold an additional bearing for each drive shaft. This way, the shaft would be supported on either side of the drive sprocket, taking most of the lateral tension off the sprocket. They work great.
Off to finish the machine!
It's about damn time.
Over the weekend I did some testing and tuning using only the x and y axises and a sharpie mounted in the router.
As you can see, with the first run (at the bottom), it started off pretty good, but as it progressed the x axis kept slipping. The problem was that since the set screw in the drive sprocket was so small (#8, no head), I couldn't really torque it down tight enough without stripping the socket and/or allen wrench. Thankfully my friend Calvin was around, and offered me a couple socket-headed screws that took a much larger allen wrench, allowing me to apply plenty of torque. While the larger heads did rub the chain, a little quick grinding with my dremel took care of that. As you can see, the final test showed no slippage at all.
Another mod I implemented at the suggestion of others was the addition of two brackets to help support the x axis drive shafts:
We had noticed that when the drive chains were tightened, it would cause the 1/4" drive shafts to flex. To counteract this, Jeff designed and milled out several pieces of MDF to hold an additional bearing for each drive shaft. This way, the shaft would be supported on either side of the drive sprocket, taking most of the lateral tension off the sprocket. They work great.
Off to finish the machine!
Wednesday, November 17, 2010
Setbacks and opportunities
In a response to an earlier post of mine where I had stated that the CNC machine was 'almost done', a friend of mine said "Great! 90% down, only 90% to go!"
This comment is becoming more prophetic than I'd like.
The machine has been capable of movement for a few days now, but the x axis has been troublesome. Even though it's being driven by a beefy NEMA34 motor that should be capable of over 600 oz-in of torque, I've been able to stop it with just a couple fingers. After sleeping on the problem Monday night, I decided to check the documentation of the motors and the driver boards, and discovered that the boards can only supply 4.3A of current, while the motor wants 5.5A. After consulting with some of my friends at the Asylum and some testing, we've decided that the best course of action is to order another smaller NEMA23 motor like the ones currently driving the Y and Z axises, which we know the driver boards can handle.
Some good news is that I had an interview with Because We Can for their internship position that went very well. However, I wouldn't be available until June, and they said that because of their size they can't reliably plan that far ahead. Still, I'm pretty optimistic about the opportunity, and will be staying in touch with them.
This comment is becoming more prophetic than I'd like.
The machine has been capable of movement for a few days now, but the x axis has been troublesome. Even though it's being driven by a beefy NEMA34 motor that should be capable of over 600 oz-in of torque, I've been able to stop it with just a couple fingers. After sleeping on the problem Monday night, I decided to check the documentation of the motors and the driver boards, and discovered that the boards can only supply 4.3A of current, while the motor wants 5.5A. After consulting with some of my friends at the Asylum and some testing, we've decided that the best course of action is to order another smaller NEMA23 motor like the ones currently driving the Y and Z axises, which we know the driver boards can handle.
Some good news is that I had an interview with Because We Can for their internship position that went very well. However, I wouldn't be available until June, and they said that because of their size they can't reliably plan that far ahead. Still, I'm pretty optimistic about the opportunity, and will be staying in touch with them.
Monday, November 15, 2010
Completion is imminent!
So close now!
The mechanics are all done, and the electronics are functional. All that's left is to finish up the wiring and software configuration, which I should be able to knock out today. After that's finished I'll do some test "cuts" using a sharpie in the router to make sure it's moving like it should, and then I'll start milling!
Other than some replacement parts and a few additional ones for the gantry, the first thing I plan on making is a toy I've been working on I'm calling the launcher. The original idea was a snow ball launcher, but then I realized that it could be used to launch pretty much anything than could fit down the barrel, so I made sure it could at least fit a tennis ball. It'll be large, unwieldy, and completely impractical, but it's a great example how a large CNC mill can be used to make things other than furniture and signage.
The mechanics are all done, and the electronics are functional. All that's left is to finish up the wiring and software configuration, which I should be able to knock out today. After that's finished I'll do some test "cuts" using a sharpie in the router to make sure it's moving like it should, and then I'll start milling!
Other than some replacement parts and a few additional ones for the gantry, the first thing I plan on making is a toy I've been working on I'm calling the launcher. The original idea was a snow ball launcher, but then I realized that it could be used to launch pretty much anything than could fit down the barrel, so I made sure it could at least fit a tennis ball. It'll be large, unwieldy, and completely impractical, but it's a great example how a large CNC mill can be used to make things other than furniture and signage.
Wednesday, November 3, 2010
Getting Close Now!
It's starting to look like a CNC!
As you can see, the machine is coming along nicely. I've attached the rails on the z and y gantries, which has allowed me to put all the main assemblies together. Jeff, one of the guys here at the Asylum, wanted to paint the torsion box with a stainless-steel paint, so it's all nice and shiny now. The next big steps will be to fasten the top to the torsion box (it's upside down now), and put it on top of the table structure. Once that's done, I can install the long x-axis rails and chains. Almost there!
As you can see, the machine is coming along nicely. I've attached the rails on the z and y gantries, which has allowed me to put all the main assemblies together. Jeff, one of the guys here at the Asylum, wanted to paint the torsion box with a stainless-steel paint, so it's all nice and shiny now. The next big steps will be to fasten the top to the torsion box (it's upside down now), and put it on top of the table structure. Once that's done, I can install the long x-axis rails and chains. Almost there!
Saturday, October 30, 2010
Busy Busy
Lots has happened in the past few days. First off, I forgot to mention on Monday that I got all the pieces for the gantry milled out by Terry at Village Sign Works and picked them up last Saturday. As you can see, I've also made headway on putting them together.
On Tuesday I put in all the orders for hardware, and today the last package arrived! Sourcing the aluminum rails locally proved to be a great idea. It turns out that there's a local company called Admiral Metals that sold me full ten foot rails; this allowed me to avoid having a join in the long x-axis rails, which would most likely have caused a small bump. I also happend to run into a fellow CNC machinist while I was there who offered to help me machine any small parts I might need. I love this town.
I now have everything I need to finish the build; the only thing I have yet to get is an old computer to run the thing, but I've got several leads. Tomorrow is going to be a long work day.
On Tuesday I put in all the orders for hardware, and today the last package arrived! Sourcing the aluminum rails locally proved to be a great idea. It turns out that there's a local company called Admiral Metals that sold me full ten foot rails; this allowed me to avoid having a join in the long x-axis rails, which would most likely have caused a small bump. I also happend to run into a fellow CNC machinist while I was there who offered to help me machine any small parts I might need. I love this town.
I now have everything I need to finish the build; the only thing I have yet to get is an old computer to run the thing, but I've got several leads. Tomorrow is going to be a long work day.
Monday, October 25, 2010
Change in plans
I've decided that instead of going to the bay area for a month, I'm going to spend the entire quarter here in Boston, and then spend a few months in Oakland after I graduate.
Here's what happened: a few days ago I read on Because We Can's blog that they're offering a couple internships, one of which is focused on the use of CNC tech. As you can imagine, my first reaction was extreme interest, thinking I could do it right after I graduated, but after a few moments of consideration I decided that I'd probably be better off just going straight into business for myself.
A couple days later I found myself re-considering this internship. As it turns out, part of my resistance to it was the fact that I was very weary of becoming too interested in the bay area as a place to set up shop because I'm already in love with Boston. As I thought about this, I realized that this had caused me subconsciously to sabotage it's chances by only spending a month there, while giving Boston the better part of two. If instead I spent a full four months in Oakland, I'd be much more likely to get a more full picture of what living there was really like, and have more time to make the connections I would need. The more I thought about this idea, the more I liked it; even if I didn't get the internship it would still be a better plan. Another benefit would be that I would then be free to spend the full quarter here which, considering how long it's been taking to get the CNC up and running, would be very helpful.
After talking to several people about this plan and hearing no strong objections, and making sure my housemate wouldn't mind me staying an extra month, I decided to go ahead and put this plan into action. I'll miss not being able to see my father and step-mother for Thanksgiving, but being able to spend that much more time with them in the summer should make up for it.
Here's what happened: a few days ago I read on Because We Can's blog that they're offering a couple internships, one of which is focused on the use of CNC tech. As you can imagine, my first reaction was extreme interest, thinking I could do it right after I graduated, but after a few moments of consideration I decided that I'd probably be better off just going straight into business for myself.
A couple days later I found myself re-considering this internship. As it turns out, part of my resistance to it was the fact that I was very weary of becoming too interested in the bay area as a place to set up shop because I'm already in love with Boston. As I thought about this, I realized that this had caused me subconsciously to sabotage it's chances by only spending a month there, while giving Boston the better part of two. If instead I spent a full four months in Oakland, I'd be much more likely to get a more full picture of what living there was really like, and have more time to make the connections I would need. The more I thought about this idea, the more I liked it; even if I didn't get the internship it would still be a better plan. Another benefit would be that I would then be free to spend the full quarter here which, considering how long it's been taking to get the CNC up and running, would be very helpful.
After talking to several people about this plan and hearing no strong objections, and making sure my housemate wouldn't mind me staying an extra month, I decided to go ahead and put this plan into action. I'll miss not being able to see my father and step-mother for Thanksgiving, but being able to spend that much more time with them in the summer should make up for it.
Monday, October 18, 2010
Construction has begun!
Last night I finally started nailing and gluing boards together. Of course there was a last minute design change to the torsion box, but it was the awesome kind that cut down dramatically on weight, construction time, and material used. Put simply, I increased the space between ribs in the box, and made each row staggered from the one before it. This change is largely thanks to Edison, one of the guys at the Asylum. God, it's nice to have intelligent monkeys to bounce ideas off of! After I cut all the new short ribs and laid down some plastic to keep the box from getting glued to the concrete, I managed to get almost half of the thing built before I headed home for dinner.
The process of getting the gantry parts milled out, while complicated, is progressing nicely. When I went down to the SETC Thursday evening, there were indeed people there, and a shiny 4x8 ShopBot capable of doing all the cuts nicely. Unfortunately, the (one?) guy who can teach people how to use it was not there, and it was unclear when he might ever return to the SETC since he was currently in the middle of grad school. I did make some good contacts though, including one guy from a hackerspace near David Square called Sprout. I'm going to try to make it there sometime this week.
I also heard back from a guy I found through 100k garages who makes signs. His business is Village Sign Works, and it's run by a guy named Terry and his son. I drove up there Friday afternoon and spent some time discussing the job and generally talking shop. He seemed very eager to help me out. We couldn't get the g-code files I had from buildyourcnc.com to work with his system, so we decided that the best thing would be for me to take the DXFs I had, separate the cuts into layers based on depth of cut, and send those to him for an estimate. It's a good thing we did this, since an extra DXF I had also been sent turned out to contain several updated parts that I was strongly urged to use. I swapped out the old parts for the new, split everything into layers, and sent the revised DXF off to Terry. Hopefully I'll hear from him sometime today with an estimate and he'll be able to get cutting in the next day or so.
The process of getting the gantry parts milled out, while complicated, is progressing nicely. When I went down to the SETC Thursday evening, there were indeed people there, and a shiny 4x8 ShopBot capable of doing all the cuts nicely. Unfortunately, the (one?) guy who can teach people how to use it was not there, and it was unclear when he might ever return to the SETC since he was currently in the middle of grad school. I did make some good contacts though, including one guy from a hackerspace near David Square called Sprout. I'm going to try to make it there sometime this week.
I also heard back from a guy I found through 100k garages who makes signs. His business is Village Sign Works, and it's run by a guy named Terry and his son. I drove up there Friday afternoon and spent some time discussing the job and generally talking shop. He seemed very eager to help me out. We couldn't get the g-code files I had from buildyourcnc.com to work with his system, so we decided that the best thing would be for me to take the DXFs I had, separate the cuts into layers based on depth of cut, and send those to him for an estimate. It's a good thing we did this, since an extra DXF I had also been sent turned out to contain several updated parts that I was strongly urged to use. I swapped out the old parts for the new, split everything into layers, and sent the revised DXF off to Terry. Hopefully I'll hear from him sometime today with an estimate and he'll be able to get cutting in the next day or so.
Thursday, October 14, 2010
CNC status update
The CNC is coming along. We've settled on the BlackFoot design from buildyoucnc.com, and I've purchased the g-code files files for it. Before we build the mill though, we first have to make a table for it to go on, and the first part of that is making what is known as a torsion box. In turn, the first part of making a torsion box is having a flat, level surface on which to build it. To that end, a frame of 2x4s was bolted to the floor over plastic, and self-leveling concrete was poured in.
A torsion box is a long thin box containing a grid of boards that form a ridged lattice. This will insure that the table to of the CNC mill will always be flat. Right now I've got most of the parts of the torsion box cut out; I just need help cutting the long sides of the box along with the top. Once that's done I'll assemble the box, build the table, and then start building the CNC onto it.
In the mean time I need to find a place that already has a CNC machine that will cut the out the parts for mine for me. Some other people at the Asylum tried to scope out a possible place called the South End Technology Center, but when they went during posted open hours on Saturday, the place was closed. Hopefully it'll be open today.
A torsion box is a long thin box containing a grid of boards that form a ridged lattice. This will insure that the table to of the CNC mill will always be flat. Right now I've got most of the parts of the torsion box cut out; I just need help cutting the long sides of the box along with the top. Once that's done I'll assemble the box, build the table, and then start building the CNC onto it.
In the mean time I need to find a place that already has a CNC machine that will cut the out the parts for mine for me. Some other people at the Asylum tried to scope out a possible place called the South End Technology Center, but when they went during posted open hours on Saturday, the place was closed. Hopefully it'll be open today.
Tuesday, October 5, 2010
Much Progress!
On Sunday I met with several people from the Artisan's Asylum about building a CNC mill. Going into the meeting my plans and dreams looked something like this: if money was no object, I would build a small mill like the one I just made in Cincinnati, power it with overpowered electronics, use it to mill out precision parts for a larger mill that could handle a whole 4'x8' sheet of ply, build that, and then use the electronics from the first machine to power the second. When it would be time to return to Cincinnati I would rent a U-haul and take the larger machine with me, leaving the smaller one. Once reality set in, I decided that a more prudent thing to do would be to just make the smaller machine; building the larger one could wait until I was back in Cincinnati. Minutes into the meeting on Sunday, several things became clear:
This means that I'll get to build and have access to a full size CNC mill, not have to worry about getting it back to Cincinnati, and all it'll cost me in the end is my time and labor! This is better than I had dreamed of! Tonight we're meeting again to decide on a design to use, and possibly get started on the table that will hold the machine. Unless someone has found another well-tested design of the size we need, we'll probably be building this one.
In other news, this weekend I'm attending StrowlerCon, another Maker event of sorts where I have been assured I'll meet lots of awesome people.
Ye gods, I owe you people a report from D.C., don't I? I'd start a list of posts to do, but I'm afraid it would only encourage me to add to it rather than actually post.
- The Asylum guys saw no reason to make anything other than a full 4'x8' mill.
- One of them was already willing to buy the machine once I left town.
- Another said he knew of several places that would mill out parts the parts for us at cost.
This means that I'll get to build and have access to a full size CNC mill, not have to worry about getting it back to Cincinnati, and all it'll cost me in the end is my time and labor! This is better than I had dreamed of! Tonight we're meeting again to decide on a design to use, and possibly get started on the table that will hold the machine. Unless someone has found another well-tested design of the size we need, we'll probably be building this one.
In other news, this weekend I'm attending StrowlerCon, another Maker event of sorts where I have been assured I'll meet lots of awesome people.
Ye gods, I owe you people a report from D.C., don't I? I'd start a list of posts to do, but I'm afraid it would only encourage me to add to it rather than actually post.
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