80/20 Extrusions

[HEAVYMETAL87]

jbolt, that is impressive. I think at at the worst mine might be used for cutting yellow metals, plastic, wood, etc.

 

[Firestopper]

The entire machines frame and gantry is made from 80/20. Most of the head is made from commonly sourced aluminum. The head weighs around 25 pounds not including the torch. The linear bearings as well as the racks are one piece. I did not build the unit but had to reassemble to realign after shipping. I also had to replace and rework several items as the seller (Dyna CNC) did some shoddy work. I got familiar (very familiar) with this machine prior to powering it up. I did build the water table and added the side metal to confine the sparks. Once I corrected manufacture shortcomings, the machine has preformed well. The overall design is very robust.

The orange cord at the top is wired to the drives for controlling on/off a router. The computer uses Mach III and Sheet Cam.

 

[Mikro]

I built my CNC router about 10 years ago. Much has changed since then. It has been a great tool for me as I build electric guitars. Here are some pictures of my machine not in any specific order. If I were to change anything, it would be to use supported rails and linear bearings, add a tramming plate to the Z axis. Change my ball screws to zero backlash type. I run a Porter Cable 690R router using a SuperPID 2 for speed control with Mach3. I have about 0.003 backlash on my Y axis, 0.005 on my X axis and 0.002 on my Z axis. Tramming is within 0.003 in 5 inches on Y and 0.002 on X. Any questions please be patient As I am not in here that often.
Mike

 

[jbolt]

jbolt, that is impressive. I think at at the worst mine might be used for cutting yellow metals, plastic, wood, etc.

Here is the build log for the small router I made for myself. It uses 8020 for the X & Y rails and the table. It used mostly for wood, plastics etc. Not meant to be high precision but I have done steel sheet.

 

[HEAVYMETAL87]

Wow thanks guys.

One of the things that has kind of thrown me for a loop on this whole thing is the ways- if one is a little bit uneven or something, can the machine compensate for this? Or will it totally botch everything?

 

[7milesup]

Hello HeavyMetal. One of the CNC machines that I seriously thought about building (copying?!) is the Grunblau machine. He had a very cool way of utilizing 80/20 material but also combining it with bent and machined side panels. His gantry system I find quite interesting with the "V" rollers riding on the edge of the bent side frame. http://www.cnczone.com/forums/diy-cnc-router-table-machines/153486-cnc.html

He used to sell "kits" but not sure if he still does that or not. The other CNC machine you may want to check out is "This Old Tony's" from YouTube. He did have an issue with his gantry being parallel and precise, just like your concern. He started with a "C" channel of hot rolled steel and eventually had a friend of his mill it flat. Like you, I too am wondering if there is a better solution for that part of the build.

 

[Richard White (richardsrelics)]

The company I work for purchased a CNC Router from a company in California, won't mention the name, but it is no longer in business. They used 80/20 material for the gantry, and personally I do not like it whatsoever. I feel it is just too flimsy and very prone to skewing. Ours is only a 50" X 50" table. That being said we also have a 5' X 10' Thermwood CNC router. That thing is beyond robust. If it were me, and it is kinda funny for me to find this post, but anyway, if it were me, I would have the gantry made out of solid aluminum, or steel to ensure it won't twist, because that is bad...
Why is this funny? because my boss, just this past week tasked me and one other Engineer, I am a Journeyman Tool and Die guy, to make an X,Y, Z table, basically a CNC router from scratch..

Building the machine, does not concern me, the software and communications is what I am curios about..
Any way, make the gantry out of solid aluminum, and the sides can be 80/20 with due diligence on ensuring extreme rigidity... Also use like at least 80 mm X 160 mm with the long side vertical, they company we bought from sis not and our machine suffers because of it..

 

[JimDawson]

If I were going to build a really robust router, I would go with a fixed ''gantry'' with a moving table. The downside of this is that the machine has a much longer footprint, about 1.5 X the table travel, and requires a bigger motor to drive the table mass.