Building Your Own CNC Machine

It won't be a top-end machine — but if you build one, you'll learn a lot. November 27, 2012

Question
We are a small shop and considering a shop built/DIY CNC. Has anyone seen it done right? I’m just wondering if it's a viable solution. There are a lot of plans and info on the web and some look pretty good for limited production.

Forum Responses
(CNC Forum)
From contributor H:
Yes it can be done and I'm pretty sure there is one shown at the Shop Built Equipment Forum at WOODWEB. If you are thinking of going that route then you should also look into used ShopBots. They are very affordable and sometimes can be found through the ShopBot website. To build your own right you are going to have to understand both the mechanics and electronic end of the machines. Linear motion, stepper vs. servo motors, PC controls, etc. are all areas you will have to learn about.



From contributor W:
I would do it for one simple reason, you will learn more about this than most all will ever attempt. In the late 80's I had no money and built myself a vertical panel saw (wish I had a pic of it). It was slow, needed adjustment, and yes I did move quickly to purchase one. What I learned about linear bearings and accuracy was priceless.


From contributor H:
One more viable option is to keep your eyes open for a used Digital Tool 900-905 (I think) series CNC. These early all aluminum 5x10 machines were serious work horses that were rugged, simply designed, and easy to modify. They were the earlier machines of the same people who own and operate CNT Motion in Pittsburgh. My first CNC was a DT902 which I beefed up a bit and for which I designed and built a 5-position tool changer. These were very adaptable machines.


From contributor S:
If you’re lucky you can find an older 48x96 ShopBot for under five grand. They are slow compared to a new ShopBot but there are still plenty of guys who make a living with them. Finding parts for repairs or upgrades is also easy. If I had a budget of two grand or less to spend I would build something from scratch. You can get way more for your money in this situation than you would if you bought a Carvewrite or a Shark for example. Make sure you have money left over for software. Software is more important than anything. Even a $500,000 router is nothing more than a cold hunk of steel and aluminum without it.


From contributor R:
My son and I started out with a small hand mill and a small jewelers lathe a second time after we lost our shop. We found a few bucks and converted to a home built CNC mill. Then we found a few more bucks and built 8" x 20" x 8" CNC router. Now we are buying the parts for a 5' x 4' x 16" table with a 3 HP router. Every month someone comes in and wants something done that is bigger than we can handle.


From The Staff at WOODWEB:
The Shop Built Equipment Forum thread Contributor H refers to in post #2 is below.

Shop Made CNC



From contributor K:
It's interesting someone mentioned a Digital Tool. I own one and the previous owner of the business bought it new in 1993. In the past five years I've learned absolutely everything about that machine - mostly by necessity as parts break down and need replacement. If I were the OP, I would buy one in a heartbeat. I remember seeing one on sale for about $5,000. New, I think mine was about $14,000. You may not learn how to build a CNC, but you'll spend just about as much as you would for a DIY kit.


From contributor E:
Our business is built around a 4x8 MechMate. We create boat kits from several designs. I recently used a 5x10 ShopBot to cut out some bigger sheets and found the comparatively lightweight gantry on the bot to be a liability. I also prefer using a machine that uses G-code. One of these days I'll build another rack and pinion gantry style machine, but for now, our current machine is working fine.


From contributor W:
I am fortunate to have a work horse and you can see a lot of digital in the CNT and CAMaster machines.


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From contributor O:
You need to assess how much free time you have available and decide if your time would be better spent earning money and paying off a basic or used machine. I'm pro-DIY and few years ago a DIY CNC would have definitely been a big saver, now not so much.


From contributor W:
I have seen a few Mechmates and will be the first to tout its best in class for a DIY machine (for a kit) when compared to stoutness (subject to a well experienced welder, and not just one who makes good welds). Yet to say it outweighs the solid of several "Entry" level machines is a bit of a stretch. Yes a decent fame and motion would start at 15 plus and at the end of the day it is well worth it.


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