# New CNC build



## MrRon

My home built CNC machine measures 36"x84". It is made of MDO plywood; a gantry design. The mechanicals are 90% complete. I've tried to maximize rigidity by using metal in key spots. I now have to get the steppers and electrical components. I have the computer running Windows XP. I do my drawings using Autocad 2004. My question is: What other items do I need between the computer and the CNC electronics. I will be using components from "Build your own CNC machine". I was going to use a Bosch VS or a Porter Cable VS router, but decided on the Bosch Colt trim router. I'm hoping to mill aluminum as well as wood. As far as the router choice goes, I can easily switch the router mounts to use any router. The photo is a year old. It is more along than shown.


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## bonesbr549

Did you go with plans or do your own? Pictures(more)? I'm starting to plan my first build!


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## MrRon

> Did you go with plans or do your own? Pictures(more)? I m starting to plan my first build!
> 
> - bonesbr549


This is the latest photo. I will try to take more pictures. The design is my own. I made my own drawings using Autocad. I studied other home built designs and tried to incorporate the best features of each. I also tried to keep the design simple and inexpensive. I have metal working machines and metal working (skills?), so I was able to make many components from metal, mostly aluminum. I work in the decimal system of measurements with a tolerance of ± .001" or as close as I can get. I make modifications as I go along. If a hole doesn't line up, I enlarge it as needed to fit. The CNC machines that are made by strictly wood workers seem to work OK. The best advise is to jump in and start building. This is an ongoing work-in-progress. I learn as I go. I think I went too big for my first machine. I have smaller designs on the "drawing board" that are exclusively metal. My ultimate objective is to mill aluminum parts for my large scale locomotive building. I think an overall ideal size would be for an 18" x 48" work surface. That size would accommodate my work requirements. The smaller the machine, the more rigid it can be made easily. The 36" x 84" may be OK for wood routing, but may not be rigid enough for working metals. Since I am so along on my project, it's too late to switch to a smaller size machine. When and if I build a smaller machine, at least I will have the electronics components and software to reuse. http://www.buildyourcnc.com is a good place for information.


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## JAAune

A lot of CNC electronics are still built for the old parallel cable systems which makes it hard to interface them with modern computers. The machine in our shop uses an ethernet smoothstepper which converts the ethernet signal into a parallel signal inside the control box.

If you're going to mill aluminum parts I strongly recommend a SuperPID. Not only does it allow for automatic control of the variable speed from the computer (Mach3 in my case), but it also allows the router to run as low as 5,000RPM without damaging the router.

SuperPID


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## bonesbr549

Thanks. I'm a computer guy, so the PC part is fine with me. I'll be going with the Parallel to USB. Got plenty of old PC's laying around to handle that. I'm not an autocad guy, but pretty good with sketchup. I've been playing with Sketchucam which is an addin to sketchup and it seems promising. I've downloaded eval copy of mach III and this may be the combo I'm going with. My goal is 48×48. Still toying between ply and 80/20. Keep posting your progress, it will help us that are farther behind you on the trail!

did you go leadscrew(single/double…directdrive or belt), or rack-n-pinion?


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## ssnvet

Nice looking build…

You asked what additional electronics you needed and I noticed that you did not mention limit switches.

I converted a bench top mill to CNC control using Mach III on an old XP PC and I have one very strong recommendation….... Find and install and old seat of XP SP2 (and of course, keep the PC off of the internet). You will not believe how incredibly fast XP SP2 runs. SP3 killed the OS (likely on purpose) with all the security features they added. But under SP2, XP runs amazingly well. Once you've installed SP3, I don't think you can go backwards, but if you can find a set of pre-SP3 disks, you should be able to re-install the OS.


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## joebob1611

Congrats on the new machine. I just finished up a Joe's Hybrid machine and am starting to learn how to use it. They are a lot of fun!. There seems to be no end to the things you can do with one of these!

I'm using a HobbyCNC Pro controller with an ethernet smoothstepper and they work great. Unfortunately the HobbyCNC 4 axis board is no longer available. Also running Mach 3 on my HP laptop and am having no problems, as long as I don't let the screensaver kick in while cutting! If you need the electronics, you can't go wrong with a kit from CNCRouterParts. Very good service and excellent quality stuff. Gecko G540 and 320oz steppers will work well, but if you do plan on upgrading to a larger machine later on, it might be worth the extra cost to look into a Nema 34 setup instead.

For a router, also take a look at the Hitachi M12VC. It's pretty popular among the CNC crowd and can be found for under $100 if you look around. I actually got mine from CPO Outlets for $120 shipped.

My machine has a roughly 50"x48" cutting area and uses rack and pinion drives. It can rapid at 900IPM on X and Y. Of course, you don't cut at that speed, but it does speed up the process when the bit can get to the next location faster.

As Mainiac Matt mentioned, you should install limit switches to help prevent running the gantry off the rails at each end. Cheap and simple insurance. You can use either mechanical or hall effect switches. The hall effect are neater and less prone to failure, but as long as you get a good quality switch you'll be fine with either one. I can't tell from the picture but if you are using two drives on the longer axis, switches will also provide an easy way to square the gantry.

Last thing - DUST COLLECTION! You mentioned cutting aluminum and wood. If you do any MDF cutting, dust collection is a must. That stuff turns to powder when cut and ends up everywhere.

Enjoy the new toy! But be careful. They are addicting!


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## MrRon

I haven't made much progress lately on my CNC. Other projects have taken priority, like a baby crib for my grand daughter.


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## MrRon

Just a word of advise to anyone wanting to build a CNC router; The biggest mistake I made in my CNC project was trying to keep it cheap. I spent a lot of time (wasted) designing and redesigning to keep the cost as low as possible. Of course there has to be some control of cost. I cannot go hog wild and buy everything I want at cost-no-object. For one, going with 80-20 probably wouldn't have broken the bank, but I opted for plywood thinking to save a few dollars, but ending up with a less rigid machine. My goal was to keep it under $1000, but I'm sure it will go at least 50% higher.


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## MrRon

Just a word of advise to anyone wanting to build a CNC router; The biggest mistake I made in my CNC project was trying to keep it cheap. I spent a lot of time (wasted) designing and redesigning to keep the cost as low as possible. Of course there has to be some control of cost. I cannot go hog wild and buy everything I want at cost-no-object. For one, going with 80-20 probably wouldn't have broken the bank, but I opted for plywood thinking to save a few dollars, but ending up with a less rigid machine. My goal was to keep it under $1000, but I'm sure it will go at least 50% higher.


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