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Krashlnd
10-28-2004, 03:49 PM
Has anyone Built one out of HobbyCNC plans? If so Tell me where in the heck you found all the lumber that it askes for...1/8 birch, 3/8 birch.. Hard to come by lumber here In Tennessee. Can I use different size of lumber but stay with the quality? Also I was going to use 1/4 x 20 thread rod for the leadscrews and cutting board plastic for the nuts. If someone has a CNC built to the specs of HobbyCNCs plans email me some pics or post them here. Last but not least what is a good driver board that can be built or bought complete. I am not looking for superfast speed. Heck I want to cut fanfold foam, Balsa and lite ply. Man please reply.
Steve

buscht
10-28-2004, 04:14 PM
Steve, I've not built this machine, but if you are talking about birch plywood
there are lots of sources on the internet.
Here's one
http://www.woodnshop.com/hardwood/Baltic_Birch_Plywood.htm?source=overture&OVRAW=BALTIC%20BIRCH%20PLYWOOD&OVKEY=baltic%20birch%20plywood&OVMTC=standard

The same guy who sells the plans, sells a driver kit. Or use a Xylotex

www.xylotex.com

If you are really talking Birch lumber, then I would think that you could substitute almost any good hardwood lumber.

cncadmin
10-28-2004, 04:35 PM
Here is my machine inspired from hobbycnc made from shop grade birch.
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http://www.cnczone.com/gallery/data/500/11CNC05-med.jpg

Chagrin
10-28-2004, 04:45 PM
I'd assume that "birch" plywood implies "baltic birch" plywood which is a vague term for high quality plywood. True baltic birch plywood would come from Russia (as the name implies) but has a standard size of 5x5 feet instead of our traditional 4x8 size.

Like buscht's link above notes, you're just looking for a "cabinet grade" or "AA" or "AB" plywood; inspect the plywood because the best plywood will consist of more-than-the-usual-quantity of layers of veneer and have no or very few voids in a cut edge.

Just because it's interesting and I like to hear myself talk, plywood is graded based on the quality of the wood used on the face and interior layers, and whether or not it is rated for outdoor use. For example, "AB" plywood would have a face unblemished by knots or voids ("A" grade) and interior layers with only a few knots or voids ("B" grade). So while they might appear the same, "AA" would be better than "AB" or "AC" etc., etc. The "X" refers to the glues used in the plywood and if they can handle outdoor use. So "ACX" plywood would be acceptable for outdoor use, but really, pretty much all modern plywood uses glues acceptable for outdoor use.

Krashlnd
10-28-2004, 05:07 PM
Great, This is a start. I am gonna try to use a good grade of ply and maby use a smaller or larger size. ( which is ever is avail ). Ok about the threadrod. Is it ok to use this and not the standerd leadscrew. I have lots of 1/4 x 20 and cutting board plastic for backlash nuts. So what do ya think?
Steve

Krashlnd
10-28-2004, 09:06 PM
Got the Lumber that I needed from a local mom and pop hardware store. Wouldnt believe that they had the Lumber I needed!! :banana: Now I am ready to Cut and hopefully have 10 fingers when I am done. Ill post pics later. Any advise would be great. I still am a newbie :) Need all the help I can get.

ger21
10-28-2004, 09:06 PM
http://www.sloanswoodshop.com/plywoods.htm It's in Tennessee if that helps any. Unlike Chagrin's recommendation, I wouldn't use a standard cabinet grade of plywood, even the expensive stuff. It'll tend to warp much more than the Baltic Birch, or the Finnish Birch in the link.

Plywoods rated AB or AC are softwood plywoods, with the lower grades like BC being your typical home construction type plywood, and not really a good choice. The stuff warps like crazy. I've seen AC in Home Depots, and even that doesn't stay very flat. With softwood plywood, the the 2 letters represent the face and back grades, respectively, not the face and core. See here:

http://www.phillipsplywood.com/softwood_generalinfo.htm#grades

Hardwood "cabinet" plywoods are rated A1, A2, B1, B2, with the letter being the good face rating and the number being the back face grade. A1 is the best face, with the best back.
http://www.phillipsplywood.com/grading.htm

I'm pretty sure the HobbyCNC plans call for Baltic Birch. If you can get it, use it.

Krashlnd
10-28-2004, 09:12 PM
Oh well I bought all oak. Oh yea it was high Priced but I am very ready to get this CNC built. Now the cutting base is lite ply. For the most part the rest is oak and popular where calls. ( Oak is used where birch is to have been used ) Is this ok??
Steve

cncadmin
10-28-2004, 09:37 PM
Oak is fine any play wood will work JUST FINE.