Prop making with CNC

[tango'd fett]

Jtechwriter, amazing work on this and very tempted, I am in the Uk so different voltage here, does this book take into account this and offer alternatives or is it only aimed at the US market?

Loving your build rebelscumm man thats a tidy workshop:lol

 

[proptronix]

As far as I can tell everything runs off of 36v DC. The book recommends using Keling's KL-350-36 which will accept an AC input of 115v - 230v 50/60 Hz

 

[the_batdemon]

that looks like an interesting way to control the x and y axis.

does the book give any suggestions on software ? preferably open source?

 

[Fetts.Sobriquet]

that looks like an interesting way to control the x and y axis.

does the book give any suggestions on software ? preferably open source?

Yea, all the software is covered in the book. There are endless options for software.

 

[Rebelscum]

Your best bet for these questions is the forum where the book is from. Seems to me about half of the people posting about their builds there are not in the US.

http://www.buildyourcnc.com

 

[the_batdemon]

cool! thanks for the link.

 

[tango'd fett]

Your best bet for these questions is the forum where the book is from. Seems to me about half of the people posting about their builds there are not in the US.

http://www.buildyourcnc.com

great link thanks :thumbsup

 

[Rebelscum]

FYI, I'm keeping some photos of my build in a gallery here: http://rebelscum.com/gallery/cnc

The build itself was very straight forward and really only about half of my total build as I'm concentrating now on a pretty comprehensive control cabinet, which is taking some time to put together.

Somebody asked earlier about resolution. I have only cut a few things just to see it work before I started on the final controls. A 2" diameter pocket in MDF measured only four thousands difference across the axis, and that would be pretty easily be somewhat attributed to trying to measure a circle in MDF and the inherent difficulty in that.

I think anytime you can get wood that close, you're closer than you need to be.

 

[propcicle]

Rebelscum - With all the CNC talk going on here lately, I'm thinking about going the home built route and just ordered the book mentioned here. Since you've had a few months to play with yours, what have you been able to come up with? Great pictures of your build BTW.

 

[Rebelscum]

I had to set my build aside when I got very deep into an overly complicated control system for it. Integrating software, three companies hardware, and stuff not working as documented prevented me from ever sorting it out.

I did get it working before I redid the controls and it works now as well, I just haven't used it very much.

I was happy with the build and decided from it that I could and should build a 4 x 4. This one was really a proof of concept for me and I'd recommend it.

 

[Droid]

Ive had a 27"x48" cnc machine for about a year now. Have made Several R2 D2's on it, you can machine every part for an r2d2 on it except for the dome.... Ive gotten quite proficient with it and can pump out a complete r2d2 body with details in less than 5 days. I work mainly with a combination of styrene and wood. Havent machined many metal pieces because of the cost of bits, but will eventually move in that direction.

 

[Droid]

here is my cnc cutting a test cut from when I first got it. I should make some new vids, since ive cut many more complex pieces, and done some multi sided machining.

YouTube - CNC Coin Slots

 

[Commander Max]

Here is my home made machine.

I designed it fit in a single car bay.
It uses a Flashcut control system with some monster stepper motors.
I had CNC setups on other equipment that wasn't working out. So I designed a router to use what I had. I use RinoCam to generate the toolpaths.

I'm running a 3 horse spindle, the design can take a much bigger spindle.
I've been very happy with it, what amazes me the most is how well it holds a shape. Lately I've been doing a lot of 3d contouring, with parts that have to match up. It cuts everything right where I want it. My only complaint is it's slow, the fastest I've run it is 50 inches a minute. I've tried about every trick and it just doesn't want to go any faster. Really its not that important, as long as it makes what I want in the end.

 

[Droid]

Did you use your machine to cut the grid?

 

[Commander Max]

Did you use your machine to cut the grid?

Yes, that's the machine working area.
Plus over 8 inches in the Z axis.

It's MDF I use it as a work surface. It can get really trashed, so I replace it about every six months(depending on the workload).
I no longer add the grid, but it does illustrate the machine's capacity. At times I wish it was bigger, at the time I designed it I only had so much room.
But with CNC it doesn't matter, I break up larger parts and put them toghether later. There are different tricks to doing that, of course it depends on the part. Some parts I add slots or tabs, most of the time I use pins. The router drills the holes and I use the holes to locate the parts. I put the pins in the holes and then have fun sliding the part around till it drops on the pins.

Another thing to keep in mind when breaking up a larger part, is to cut the part short in the areas where the part has to be put together. I give about .004"-.008" depending on the material and what I'm going to do with the parts later. Another thing I do when assembling a larger part is to make a jig to position the parts for assembly.

 

[Droid]

Yes, that's the machine working area.
Plus over 8 inches in the Z axis.

It's MDF I use it as a work surface. It can get really trashed, so I replace it about every six months(depending on the workload).
I no longer add the grid, but it does illustrate the machine's capacity. At times I wish it was bigger, at the time I designed it I only had so much room.
But with CNC it doesn't matter, I break up larger parts and put them toghether later. There are different tricks to doing that, of course it depends on the part. Some parts I add slots or tabs, most of the time I use pins. The router drills the holes and I use the holes to locate the parts. I put the pins in the holes and then have fun sliding the part around till it drops on the pins.

Another thing to keep in mind when breaking up a larger part, is to cut the part short in the areas where the part has to be put together. I give about .004"-.008" depending on the material and what I'm going to do with the parts later. Another thing I do when assembling a larger part is to make a jig to position the parts for assembly.

I have the same thing, my mdf is pretty trashed at the moment. I need to replace it. I never thought of the grid, but its a brilliant idea, will help keeping alignments when machining, ill try that when i switch out mdf next time.

 

[Droid]

what kind of things have you made with yours? I have been using 2 pieces of software, cut3d and cut2d from vectric, and I run the machine with Mach3. Cut3d does a great job at breaking up complex 3d models into slices you can assemble later. the only thing with that is finding high quality 3d models. you can find some in Google's 3d warehouse, but very few are production quality models. I wish my 3d modeling skills were a bit stronger. I can model pretty well in google sketchup, but usually thats only good for things with fairly straight lines.

 

[Commander Max]

Thanks for the comment. The grid was helpful in the beginning, later on I found it got in the way. I do recommend creating one with your machine, it gives you an idea of where to put things. These days I use the pin trick in coordination with the origin, that allows me to place the parts.

There are some nice models out there. But from what I have found they are normally not very accurate. Unless you use a mesh from a show. Those are out there but you have to look or have friends around. I can't help you there.
The only advice I can give is to look around the 3d model sites. But be prepared to do a lot of model rework. Or better yet just create what you want. I've found in life if you wait for somebody else to do something, you'll be waiting a very very very long time. Even then there is a very good chance that it will not meet expectation.

I use Autocad and RinoCam to create and process parts.

Anything I say is nothing without pics.
So here is one of the largest parts I've done to date.

Note: there is 1/2" ball end mill in the spindle.
This part is about 2.5' in radius(51.6" across x just under 7" high). It's one third of a larger part. Sadly it didn't work out, I have since redone the part along with the rest of the model.

That's another thread.

 

[Droid]

here is a link to mine cutting an r2d2 leg piece, not as advanced as your setup, but it does a good job on large and small tasks for me.

YouTube - Cnc cutting an r2 d2 leg piece

 

[Commander Max]

The classic industrial erector set, for what your doing it's perfect. You don't need a lot of strength to route MDF.

Do you use other spindles with your machine?