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CNC-what's it costing you?



Ascinder
11-11-2010, 06:16 PM
So how much are these hobby/homebuilt setups you guys all seem to run costing you? I have looked at/been interested in CNC in the past, but after seeing some pricetags of the 2 axis machines, I had some sticker shock. I have a CNC setup on my hobby mill/lathe that has never really worked properly so it left a bit of a sour taste in my mouth. Also if anyone is near Reno or ever in the area, I'd be willing to throw down some cash for you to take a look at my mill/lathe setup and maybe see if you can figure out what's wrong. Also, since I have the controller/software already, would it potentially be adaptable to a 2 axis table? The system I have is an older flashcut CNC setup. I don't really know the particulars since I don't have the info on me right this minute.

Gadget
11-11-2010, 06:43 PM
I spent around a grand to get my table running for plasma. I spent some more for 3d router software, about $400 additional.

Ascinder
11-11-2010, 06:52 PM
That actually sounds reasonable. What size table is that for? And how scalable is the sizing? What I mean is how much more would you estimate it cost to go from ~2x2 to a 4x4 table?

Gadget
11-11-2010, 07:38 PM
Mine is 25X37 and is made of 2x4 lumber and EMT so scaling larger wouldn't be too bad. Lead screw cost would be higher but if I had to do it again I would use belt drive not lead screw.

Ascinder
11-11-2010, 08:14 PM
Why is that? How do the belt drives work vs. leadscrews? Wouldn't there be more strech/lash in a belt drive vs. a leadscrew? I imagine the belts would take less force to run, but I would imagine the leadscrews would be more reliable dimensionally.

Gadget
11-11-2010, 08:43 PM
The belts are faster and dimensions would be pretty good. It isn't a endless belt setup, it us used kind of like a rack and pinion, both ends are anchored. Lead screws will whip when they are long and will cause that to show in the work. Plus there is more friction taking more power to get the needed rapid speed.

Ascinder
11-11-2010, 09:03 PM
So would you you say a belt design would cost more or less than a leadscrew rig? I would imagine less. I can see where you are coming from with the leadscrews being more power hungry as they would weigh considerably more than a belt. How would you rate your setup as a potential production piece? Do you think it would fare well for more than hobby use? I am interested in just light production and maybe some prototyping initially, and would probably end up with a Torchmate unit if business allowed me to do so.

KHK
11-11-2010, 11:00 PM
I think that you are doing CNC every day, go with the screw drives. Belt drives are great for hobby use, and they are cheap

Gadget
11-12-2010, 06:13 AM
If all I run is plasma I think my table would work fairly reliably for light production work. I've had it going for over a year now and haven't had any issues. Another thought is you could use chain drive in the same way I suggested for belt drive if the sprockets fit the chain well, it might be more durable.

ISKI
11-12-2010, 01:14 PM
I was fortunate enough to remove the lead screws, steppers, belt drives and power transistors from some old equipment for free. Keep your eyes out for any junk that has steppers (old plotters, printers, …). The stuff does not have to work. I will need to get the 3d Software, but have eight steppers, 2 three foot lead screws, 2 two foot lead screws, and 2 one foot lead screws. I have some slides and most of the mounting hardware. My CNC will not be as nice as others since I will need to cut up and modify stuff, but it should be stout. I know that I’ll be purchasing some stuff, but I’m almost home just by keeping my eyes open for junk.

minnfatz
11-13-2010, 01:10 AM
I have a Precision Plasma brand table (4'x4') and controls from CandCNC. I have about $4K invested in the table, controls, and software, which is higher than the homemade ones, but I have gotten stellar customer service from both companies. I would have gone crazy trying to build one on my own.