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My "on the cheap" CNC router build
- Thread starter scottyd
- Start date
This is cool but isnt the fun of building your own bass is thats its Not CNC like hand built like the Old Stuff and New Expensive stuff
Personal opinion but to me building a bass is about getting something that's not available to buy or would be prohibitively expensive for me to buy. The tools I use to reach that goal don't really matter to me as long as they do the job and don't cause me to have to do more work. Honestly the only difference between a CNC router and the standard router and template is that there isn't some doofus holding on to it
.That doofus would be me.
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Have you seen any of @scottyd's work? He paid his dues long ago. Can't wait to see what he does with his new toy drool
Hopkins
Commercial User
After building a couple dozen instruments, the part of the process which involves a CNC is pretty rudimentary anyway. For a new builder the basic woodwork is a major step, but after a while it almost gets boring. Like I said earlier, all the CNC does is save a bit of time on the front end of the process. There is still of hours of fine tuning that goes into the wood work after it comes out of the CNC and even more time is required for finishing. Using a CNC does not at all take away from the quality of the instrument or the talent of the builder.
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I do agree cause it can suck cutting up wood forever and the CNC way Im sure prevents OH CRAP moments too
^ That
CNC is another tool, not some magic machine that removes the artistry from the artist.
A cnc cant level and dress frets, setup relief and action. Cant laminate, cant glue.. It sure cant design the models I have. What it can do is the rudimentary work that a small operation like myself have that limit production. Any builder who is pushing out more than say 75-100 a year, they have help whether its from a machine or from a staff.. regardless they aren't doing it alone.
Yes of course in that circumstance I just meant like if I was building one bass for myself But certainly not in your case
It's getting there, this is a little frustrating but fun!. I now have the gecko driver and it's made a world of difference. I have my steps per unit set off a ruler for initial setup. The z axis isn't spot on quite yet as you can see it's zeroing a little premature. I need to set them all with a dial. It's still using the junk lead screws in this video. I'll order better ones soon. I've located a couple of areas that need reinforced for rigidity. It's crazy to me the random order that the gcode generators put the cuts in.
Unless I'm miss-understanding, it's like a Windows boot-up, all random, and never in the same order.
Even with the old MOOG tape machines (pre CNC) everything was in sequential order. Random would seem to cause more machine wear-n-tear and take more time to complete the operation.
That's all from the code, it starts doing plunge cuts for whatever random reason, maybe to clean edges. I'm not sure. I generated it using jscut which so far I've noticed does odd random things. Only using that because it's fast and easy. My guitar stuff I've been using sketchup with a cam plugin.
Random like cutting half a letter and jumping over to another, cutting it then another skipping a letter then cutting a few as you'd think it would and then jumping over to finish a previously started letter. Just as in the video shows it skips around using the jscut code.
I see. I have no experience with jscut, but I suspect that the font may cause problems. Most fonts are made from vectors that aren't "clean". Using fonts that consist of a single line that the bit is to follow may work better than a font that have entire areas that needs to be routed out. This is especially a problem on small text as the bit may not "fit inside" the area to be routed.
Did that make sense?
I see. I have no experience with jscut, but I suspect that the font may cause problems. Most fonts are made from vectors that aren't "clean". Using fonts that consist of a single line that the bit is to follow may work better than a font that have entire areas that needs to be routed out. This is especially a problem on small text as the bit may not "fit inside" the area to be routed.
Did that make sense?
Makes good sense. I've got some font that I converted using inkscape to svg it Inkscape seems to convert better.
As a side note, I'm losing steps. For example in the pic above when the router makes a revolution on the body shape it'll be off a few steps on the next cut. I've tried it on slower feed rates with the same results.
I think it's my power supply, it seems weak. I've ordered a 450watt 48v 12amp supply the one I have now is 20v supposedly 7amp. I can't seem to get the best performance from these motors and I suspect it's the supply. Any ideas?
There may be several reasons why you are loosing steps. Acme screws have slightly higher friction than ball screws, and having bent rods certainly won't help.
In general a stepper motors have high torque at zero RPM, but very low torque at high RPM. Increasing the voltage will give you a bit higher torque at the cost of higher motor temperature. The first step is lowering the speed to see if you are still loosing steps. You could also try slowing down acceleration a bit. You do have a lot of mass that need to rotate, and fairly stiff couplers which doesn't like quick acceleration.
Try jogging each axis at different speeds while holding back with your hands to get a feel of how much torque you have at your disposal. You may be surprized how much speed affects torque.
There may be problems with signal noise as well. Try making a reference point, run a long program in free air and measure position relative to the reference point.
Oh, and try cranking the motors by hand (Disconnect from controller first) to see of everything moves smoothly.
In general a stepper motors have high torque at zero RPM, but very low torque at high RPM. Increasing the voltage will give you a bit higher torque at the cost of higher motor temperature. The first step is lowering the speed to see if you are still loosing steps. You could also try slowing down acceleration a bit. You do have a lot of mass that need to rotate, and fairly stiff couplers which doesn't like quick acceleration.
Try jogging each axis at different speeds while holding back with your hands to get a feel of how much torque you have at your disposal. You may be surprized how much speed affects torque.
There may be problems with signal noise as well. Try making a reference point, run a long program in free air and measure position relative to the reference point.
Oh, and try cranking the motors by hand (Disconnect from controller first) to see of everything moves smoothly.
