Newbie- Can't make up my mind, have about $1,000

[devo9er]

Hello! That's right, I'm a newbie. First post here. I'm looking for some advice in which direction I should head. I'm new to the cnc world but have some experience with stepper drives and am pretty handy in the shop with fab work.

I'm in a bit of a time crunch and need to get this thing off the ground in the next few weeks so I can finish some prototype work. I've got about $1,000 to spend. I already have a few nice spindles and computers so no need to include that in the build cost. Really just frame, hardware, steppers/boards.

I need something that will do at least 20" x 32" x 3". I've been looking at the Joe's model and am contemplating just buying the MDF/HDPE parts from his site to save myself the headache. It's $625 delivered which is a little more than I wish, but by the time I spec and cut all the pieces....You know how it goes sometimes when you try to save a few bucks by spending time..

For the motors etc I was looking at the:
probotix 3-Axis ProboStep Stepper Motor Driver Kit
$329.95

Would this work good for the Joe's 2006?

The other thing I can't help but think about is just fabbing my own (still using the probotix kit) but going super cheap on everything else. Precision is not of my upmost concern as it really just needs to cut out the same thing a few dozen times that has a better repeatability than I have with a scroll saw.

I just can't find a way to keep a machine of this size under budget with out building from scratch. Thanks for any advice!

[Phife]

$1000 and quick dont really go together in this case. Another cost you didnt mention was the software to run the machine.

The parts you quoted are already almost your entire budget and you havent included the cost of the screws/r&p, misc. hardware, wires, safety switches, other electronics.

There are machines available that are smaller than what you would like but can be bought complete for around $1200-$1500. Still need software, which can easily cost as much as your entire machine.

[jasminder]

Originally Posted by devo9er Hello! That's right, I'm a newbie. First post here. I'm looking for some advice in which direction I should head. I'm new to the cnc world but have some experience with stepper drives and am pretty handy in the shop with fab work. I'm in a bit of a time crunch and need to get this thing off the ground in the next few weeks so I can finish some prototype work. I've got about $1,000 to spend. I already have a few nice spindles and computers so no need to include that in the build cost. Really just frame, hardware, steppers/boards. I need something that will do at least 20" x 32" x 3". I've been looking at the Joe's model and am contemplating just buying the MDF/HDPE parts from his site to save myself the headache. It's $625 delivered which is a little more than I wish, but by the time I spec and cut all the pieces....You know how it goes sometimes when you try to save a few bucks by spending time.. For the motors etc I was looking at the: probotix 3-Axis ProboStep Stepper Motor Driver Kit $329.95 Would this work good for the Joe's 2006? The other thing I can't help but think about is just fabbing my own (still using the probotix kit) but going super cheap on everything else. Precision is not of my upmost concern as it really just needs to cut out the same thing a few dozen times that has a better repeatability than I have with a scroll saw. I just can't find a way to keep a machine of this size under budget with out building from scratch. Thanks for any advice!

Hi devo,
i would say that the probostepVX is not a good option. they get very hot when used with monster motors(3A 40V) and heat sinks don't cool them down even. the motors from the probotix are also getting very hot while operation. See my build on cnc zone.
http://www.cnczone.com/forums/showthread.php?t=107017

But if your probosteps are working fine then go with it and please do tell me how to cool them down and the steppers too.
regards,
jasminder singh

[jasminder]

Hi friends,
here are the updates of the build,

I fininshed the XY table, mounted the motors on them and the whole setup was put on a runnning 6FT big lathe to test the precision i can get from my XY table.
See the pictures.

Unfortunately, the finish was not as good as a cnc. The slope at the tool's position is arround 0.001 inch approx when checked with a bar. But i guess it should make polish cuts of 0.005 inch atleast. May be beacause i am using HSS tool for cutting.
Well i just fried my parallel port so i will check the setup with carbide inserts later that i just got from the city.

jasminder
if your luck wants you to loose, give it a fight.

[MrWild]

Even building from scratch $1,000 is pushing it. Your work envelope is large enough you will want multi-start lead screws and decent motors. Hardware alone can run you $1,000. Truth is, if you need the machine for prototype work you need now, you should farm out the prototype and work on the router. Unless you know what you're doing, have built one before, or are handy with your hands, building one takes a fair amount of time for the first timer.

There are quite a few free programs out there for CADCAM and EMC2 is free for motion control, but hardware isn't cheap if you buy quality, and that's one thing you should splurge on.

[devo9er]

As far as the software goes I was planning on trying to use the open source software available. Also If I can talk my brother into it, he has Mach and some other CAD/CAM on his machine. Any student discounts.? lol?

I also do realize the larger you begin making your machine the higher precision and expensive the parts need to get. For what I'm doing I really am only looking for something ±.01" if even that. Mostly 2D shapes out of plywood is all I need this thing for. Down the road when my budget allows I would love to make a hobby of this and dial this thing down to science.

Don't get me wrong I love the sound of Gecko drivers , 5 start lead screws, and fully supported rail slides but unfortunately I am willing to sacrifice a bit of quality to keep initial price down. Like many before me I hope to maybe use this machine to create the next.

I guess my questions are, although not ideal, will the probotix kit work for now? Are single start Acme screws okay? I do have a few weeks for a build just not months or years. Like someone else here "I don't need another hobby to feed my other hobby right now" lol