Poor man's tooling board?

[dbb-the-bruce]

Just went looking to purchase some Renshape - or similar material for "tooling board" - stuff used to learn CNC, mock up parts etc.

The real stuff is expensive, comes in large boards and not easy to find. (yes there seems to be lots of off cuts and leftovers on ebay - but in general still pricy)
I need a fair quantity consistent sized pieces (1" thick and smallish rectangles 3x5).

Any suggestions for affordable material that's cheap, machines easy (CNC), somewhat durable?
Ideally available at a box store or something local.

I'm mocking up objects (hand held art) prior to committing to more expensive material.

Worst case I'll just bite the bullet and buy one large board that will last years directly from Freeman.

 

[brino]

I know @JimDawson here uses MDF for all kinds of CNC backer boards.
It is cheap, stable and won't kill your end mills when you cut into it so it's sacrificial.

I will try to post back with some specific links to his projects using it.

Use two 1/2" pieces to give the 1" you want.

Brian

 

[brino]

Here's some threads were Jim talks about using MDF.....

https://www.hobby-machinist.com/threads/work-holding-ideas.34781/post-294275
https://www.hobby-machinist.com/threads/how-to-hold-and-make-this.79124/post-676513
https://www.hobby-machinist.com/threads/2014-potd-thread-archive.103222/post-183993
https://www.hobby-machinist.com/thr...ing-and-milling-sheet-goods.24379/post-216369

I hope this helps....

Brian

 

[ARC-170]

The adult school machine shop I sub at uses wood blocks. They aren't too picky; one of the other teachers brought in some wood from some cabinets. I think as long as it's not warped, cracked, split, etc, it will work.

MDF works but the dust is nasty, so wear PPE.

 

[dbb-the-bruce]

MDF works but the dust is nasty, so wear PPE.

Yeah, I've worked with MDF and routers before. This is small stuff in an enclosed CNC will hook up dust extraction at the spindle if I go that route.

 

[C-Bag]

Would Azek board be cheaper? I found out about it when we had a remodel done where the guys used it for different trim pieces instead of wood. It's expanded pvc I guess? I used it to make some clamps and other stuff. It machines nice too.

 

[GeneT45]

Would Azek board be cheaper? I found out about it when we had a remodel done where the guys used it for different trim pieces instead of wood. It's expanded pvc I guess? I used it to make some clamps and other stuff. It machines nice too.

Is Azek the same consistency throughout? I use PVC trim board for some stuff, but the center I can best describe as 'dense foam' with an outer skin that is 'solid'. I use it for a lot of blocks with holes drilled in them, but wouldn't use it if I were going to remove all or most of the top surface.

It's biggest disadvantage (to me) is that 1" x 3" is about the biggest cross-section I've found.

GsT

 

[borges1]

azek or any pvc trim would be several orders of magnitude more expensive. it does not come in much bigger than nominal 5/4x12"x20', so basically 1" slabs. its nasty cheap plastic in my opinion. the dust is insidious, toxic and gets everywhere with static cling. it also melts to blades and tooling. i'm not sure why it became popular. as a trim product (which it is primarly marketed for) it does not paint well, comes in very limited color options and has the largest thermal expansion/contraction of any building product i have ever seen.

MDF is comparatively benign, can be had with completely nontoxic bindders if you want, but often still has a lot of gross glues in it. the dust is yucky but way better than pvc. its much cheaper than pvc, and if you find someone who uses it for anyting commercially (i do for cabinet parts) they will give you as much scrap as you want. It can pretty easily be glued up to much larger blocks with glue lines that would be much less visible and would machine more evenly than the 'skin' on pvc i would expect.

Why not use solid wood for test projects? Something dense like hard maple or sapele seems like it would be evenly dense and coulc work. again find a production shop and make a friend.

 

[dbb-the-bruce]

I'm going to go with MDF. My only experience with renshape has been small chunks provided with my initial (small) CNC. I just kind of assumed that it was some form of architectural or other common material that had been repurposed for CNC test and prototyping, and I was hoping for an "oh just go buy this stuff from a box store" kind of response. I was disappointed to find out that it is explicitly for this type of stuff and expensive. Anyway, good to know and maybe I'll use it at some other point.

I also have pretty extensive experience with working with wood. Right now I'm looking for something that has no structural preference (wood grain) and is not very porous. MDF wins on the no directional preference and I can epoxy the surface to deal with porosity / feel if I really need to.

Something dense like hard maple or sapele seems like it would be evenly dense and coulc work. again find a production shop and make a friend.

Thanks for the suggestion - I have a number of wood working friends and a significant quantity cut offs and ends - 4 to 6" thick billets of Ash, Cherry, Apple, Basswood most of it harvested locally (some by me personally). There is also an architectural woodworking firm nearby that I used to get thick Mahogany (6"!) off cuts from. It's mostly about the grain and the fact that I'd like to use this stuff for other projects that show the wood. Checkout davidbelser.com for examples of work I've done in the past. I've been focusing on metal now for the last 4-5 years.

 

[Eddyde]

MDF is available in 1" and even 1.5" thick.