[georgeburns]

Hi, long time lurking, first time posting.

I've been interested in making my own CNC router for a while and finally decided to start and hopefully post progress along the way.

I read in another post that it was good to post your capabilities and end goal prior to starting, so that is what I will do.

Caps...
Table Saw, Drill Press, Grinder, Air compressor, brad and finish nailers, skill saw, circular saw, saber saw, router, roto zip, tile saw, hand drills, sanders, paint guns

I have experience in furniture making, computer programming and networking, soldering, and cable making.

I have no expierience with working with metal but I'm a fast learner.

End Goal...
A 2 foot by 3 foot or 4 foot by 3 foot table with 3 axis for wood routing and maybe some aluminum cutting.

I would like to be able to make wood plaques with drawings on them along with fonts around 12 pt.

Want to spend between 500- 1200 depending on whats needed.

First question. What do ya'll recommend for this?

Second question. I'm thinking about being spendy in some areas, but not in others. Which areas do you get the most bang for the buck?
a. Motors and Drivers?
b. Screws?
c. Rails?


Right now I'm thinking xylotex 269 system, acme screws, and gas pipe rails. Where could I see the biggest performance/precision gains?

Thanks for your time.

[harryn]

Hi - welcome to the forum.

My suggestion is to read the build logs for about a month or two. There are so many helpful ideas there, along with suppliers, etc that it is time well worth it.

BTW, don't forget to read the last two pages of each build log - that is where they go back and fix the mistakes.

As far as budget, it is very easy for even the most frugal to go 2 x those numbers. IMHO, the main advantage of screw based designs is that they tend to be either precise - or not work. Getting the precision needed takes more patience than I have. I am on a rack and pinion kick at the moment.

[BackyardWorkshop]

Hey georgeburns - I'd say "welcome" but you've probably been here longer than me! hehe

I'm working on my own CNC machine as well - looks like we both have the same end goal in mind almost - mine was wood, plastic, and aluminum

I'm building mine from MDF and angle aluminum for the rails rather than the pipe idea

[georgeburns]

Hey georgeburns - I'd say "welcome" but you've probably been here longer than me! hehe

I'm working on my own CNC machine as well - looks like we both have the same end goal in mind almost - mine was wood, plastic, and aluminum

I'm building mine from MDF and angle aluminum for the rails rather than the pipe idea

Ya, I've been looking at your thread. I'm wondering if my laziness is going to make me spend an arm and a leg on this thing. I'm looking at 55 inch rails from this site... http://www.vxb.com/page/bearings/PRO...ystems/Kit7429

And then maybe some of their plain rod for the other two axis. I'm wondering with the plain rod if I use the simple cheaper not pillow block bearings how to attach the wood for the gantry, etc. any ideas?

Just found out my foosball table which I never use is the perfect size for a table for this thing. 55 inch by 33 inch. matches the linear rails above.

Perhaps I will have the first CNC on the site with it's own ball return.

[chazmtu]

Hello,

I took a look at the link above and it looks similar to what I used for my 1x2 ft table. I bought some 1/2 in motor shafts from Grainger for about 20 bucks each and used bronze bearings for two of the axes. Worked pretty good but they are a little small. Also if you want plain ol' acme rods I got some from ebay store premachine2004 16tpi for pretty cheap though said he would do custom job. Just my 2cents. Good luck with the build.

Chuck

[BackyardWorkshop]

Perhaps I will have the first CNC on the site with it's own ball return.

LOL that's too funny! That's a great idea to use the foosball table - should already be leveled - ya? nice

and that site has some nice looking stuff - stuff I'll use for my next machine! this one's gonna be a cheapo just to get into it

although I saw some project CNC machine on eBay the other day for like $599 - I wish I'd seen that before I started LOL - but it's been fun so far building this thing

[georgeburns]

I think I have decided on my electronics but wanted to run it by the pros first...

Power Supply...
http://www.powersupplydepot.com/prod...oduct=17042+PS
24V @ 8.3A METAPO POWER SUPPLY

Steppers...
http://www.kelinginc.net/SMotorstock.html

9: NEMA 23 BIPOLAR STEPPER MOTOR 282 oz-in, ¼” Diameter Shaft with flat
KL23H276-30-8B (Dual Shaft) Specification Price: $39 ( in stock)
Torque –Speed Curve

And Gecko 203V drivers.

Does anybody see a problem with this setup?

[ger21]

Get a bigger power supply, something like this.
http://cgi.ebay.com/39V-400W-CNC-Mil...742.m153.l1262

[georgeburns]

Get a bigger power supply, something like this.
http://cgi.ebay.com/39V-400W-CNC-Mil...742.m153.l1262

I'm pretty dumb when it comes to the power portion. Why would you suggest this one. To my ignorant eyes, it seems overpowered... what are the benefits? Thanks for your time.

[ger21]

A stepper motor's speed is proportional to the voltage supplied. By going to 40V, you'll nearly double your top speed. Using a 24V supply won't really take advantage of those Gecko's. At 40V, the torque curve for the motor would look a bit flatter, with the torque not dropping off as fast as rpm's increase.

[georgeburns]

A stepper motor's speed is proportional to the voltage supplied. By going to 40V, you'll nearly double your top speed. Using a 24V supply won't really take advantage of those Gecko's. At 40V, the torque curve for the motor would look a bit flatter, with the torque not dropping off as fast as rpm's increase.

Got it, thanks for your help. I've got a ton to learn.

[ger21]

I'd suggest spending as much time learning as you can before starting to spend money. I don't think you should be buying motors before you know what you're building. And the power supply as well, since the motors will dictate it's requirements.

[georgeburns]

Would this power supply be similar?
KL-320-36 36V/8.8A
110V/220V $59.95

http://www.kelinginc.net/SwitchingPowerSupply.html

[Gir]

They are similar in the sense that they have similar output, yes.