Joe's CNC Model 2006 (Mods & Additions)

[DayneInfo]

I have the SketchUp files. Send me a PM with your email and I will send them to you.

Dwayne

Found the original files here http://cnczone.com/forums/showpost.p...&postcount=732

You can just download them from the link above if you like.

[Serb]

Originally Posted by DayneInfo I have the SketchUp files. Send me a PM with your email and I will send them to you. Dwayne Found the original files here http://cnczone.com/forums/showpost.p...&postcount=732 You can just download them from the link above if you like.

Thanks D,

I downloaded the pack from post #130 and all of the versions are there.

I had the Z axis sliding part done a while ago because with plastic parts and the router being so far out it was giving me too much vibration when cutting aluminum. Here are some pics of it. For cutting wood and doing engraving the original design is perfect for the money.

The Capture.jpg is a new design made out of steel. I ended up getting all the linear bearings and stainless rods as a freebie so I had to jump on it. The X-axis slider has a dual bearing block and I need to insert another single bearing slider next to it since the Y gantry leg is 9" wide. The bottom horizontal connector between the Y gantry legs is a 2 X 6 steel purlin and the top bridge is the same, 2 purlins split and welded together to make it wider. There will be a 1/4" steel plate welded inside the purlins' ends so that they can be bolted on. The Y gantry legs are 1/4" steel plates and I'm contemplating of having the machine shop mill a 1/8" deep blind hole for the 3/4" horizontal rods, then I can drill, tap, and screw them on.

I'll post the final drawings when I'm done with it. All of the steel parts can be purchased relatively cheap. A single stock length of a 2 X 6 purling can be used to produce all the parts and with plenty of leftover to even make a new table out of it. I'm getting all of the 1/4" steel plate parts plasma cut by my steel supplier for $35, can't beat that.. The only critical deal here is the 60" long rod. A 3/4 drill rod will flex up to 1/8" on that length where a stainless will cut that down to a fraction but a simple solution to that would be to place an additional single bearing support running on top of a L-angle below the linear bearings (with some brushes on either side of the bearing in case some trash ends up on the runner).

[mhiggins]

I had intended to wait until I was closer to completion but after seeing some action on this thread I have decided to jump in.

I have been working on a new gantry for my 2006 which incorporates design elements from Joe's 4x4 as well as mods inspired by other DIY machines, commercial units and some of my own ideas.

The carriage can run outside of the gantry uprights on both sides to allow for an upcoming 4th axis on one side and a future tool changer rack on the other.

I will probably start a new thread on this with more information and pics in the near future. I will post a link when I do.

[Serb]

Hig, that looks promising ,

Nice concept, but you are still riding on the mdf base, plus you are going 2 foot out. The angle iron support was invented by me, way back, and it does well for wood.

Besides mdf construction and since you have aluminum extrusions I really want to bring up a fact about the process of machine design. Any production machine is prototyped in aluminum, hopefully not in a 80/20, designers have their own 80/20's, extruded shapes that work better and are much cheaper when you have your own dies. This is where the limits are tested and then the order goes out and usually a company in Holland is willing to make a caste production model for a cost plus the rights to sell. This is a standard, ask Joe; he didn't pop out of the woodwork and invented a wheel, he came up with the decent low budget deal and God bless his Texas soul.

I'm not saying that you do not have a good idea. It is great. But you have to realize that your spindle will be dancing like cow's piss on a flat rock out there if you decide to push it on some aluminum angle sliders. Just like me with my previous wife.

[mhiggins]

Hi Serb,

If I didn't stay with the MDF table this wouldn't be an upgrade it would be a new machine.

All DIY projects are essentially an exercise in R&D. We try things to see if they will work. When things don't work, we make changes and try again. I can't guarantee that my mods will be successful but I'm hoping they will be. If not I will take that lesson and apply it to the next attempt. It's all in good fun anyway.

I'm using the same steel angle and bearings as the Joe's 4x4, so I think that part is pretty well proven. It's everything else I need to worry about.

[mhiggins]

Here is the link to my new build thread.

http://www.cnczone.com/forums/showth...030#post693030

[Serb]

I finally got the baby done. The linear bearings and rods were a freebie so I can't complain but if I had to purchase them I would go with rods that have continuous support and open linear bearings. The 3/4" rods on the X axis were sagging in the middle due to the weight of the Y gantry so I added a flat bars and installed 2 bearings to ride on it on each leg of the Y gantry. In order for the same bars not to flex along the Y direction while cutting I added a 1/2 X 1/2 U-channels at the bottom of the table and made a guide that rides on it from a UHMW 3/4" material. I had to use the same method w/ 1/2 X 1/2 U-channel and a guide for the Y gantry. The two 3/4" rods did not sag in the middle but they were flexing in the opposite direction of the X travel; when the Z gantry was extended all the way down the top rod was flexing one way and the bottom one was doing the opposite. This is why I wish I had rods w/ continuous support so next time I'll attach a spec sheet to the freebie orders. Another thing I noticed is that there is a little play in the Z slide. I did use 2 linear bearings per rod but the self aligned bearings within the bearing blocks have too much play for my taste so I'll end up replacing them with some linear bushings. On the X rods I have long bearing blocks w/ 2 bearings in it and a single block w/ a bushing on each side and on the Y rods I have long bearing block w/ 2 bearings in it and they work just fine.

[flyhigh]

I am planning on building either a joe's cnc or something with a similar footprint. First of all, thanks to Joe and everyone else for allowing me to begin my project so far ahead of anything I could have come up with on my own. I have read this thread and the main joes2006 thread. I still can't easily pinpoint the major weaknesses of the original design and how to correct them. Here are some of my ideas, any comments or additions would be excellent:

• The supports for the pipe on the x axis seem to allow the pipe, if it is not attached to the u supports, to sag down and out. Would it be better to simply use something similar to the y axis with the supports between the pipes? I am also thinking of filling them with concrete, although, from what I understand, it is a good idea to pass a through bolt down their centers(?).
• All pipe should be polished.
• There is a bit of whip in the x axis. It is best to have two spaced bearings at each end along with a tensioning system.
• Due to backlash, one should stay away from the spider couplings and go with direct couplings. A counterweight damper on the motors is a great addition.
• It seems that many people like to stiffen up the gantry, either using angle brackets or through bolts, or both. I wonder if there are better options for this, such as cutting two sides to the gantry each out of one piece of mdf.
• a more advanced type of anti-backlash nut is important.

Lastly, Has anyone tried using v groove bearings and a rectangular bearing mount, and did it work well?

Once again, thanks! I am looking forward to your tips, particularly if my list shows that I am not paying attention to something important.

[firlefranz]

I've made some small additions to the original Joes 2006 while I tried to keep the original design in the new parts.

At first I installed a rail at the backside of the gantry, which is simply attached to the PE bearing mounts. The rail is used for the limit switches and the cable carrier.
A similar attachment is mounted to the right side close to the Y-axis bearings. Also here the cable carrier is connected, as well as the limit switches and some part to fix the hose from the vacuum.
To clean the the parts while cutting the vacuum is connected close to the router. The brush is fixed by some strong magnets to remove it quickly when necessary.

Greetings
Cornelius