Build Thread- 15' long 8' wide Ex-Boeing CNC *REBUILD*

[diyengineer]

PICTURES & specs will be uploaded tonight!

Purchased last Tuesday, want it up and running by the end of summer.
Main intent purpose, Cutting aluminum sheet (.063").

I will need everyones guidance and 2 cents on this rebuild! Should make for a awesome summer project!

-Thanks

[Al_The_Man]

Did you find out what motors are on there?
Al.

[advt001]

Diy did you stop on your other project?

[diyengineer]

The other project is 99% done engineering wise in solidworks. Just needed to make spacers that harness the ballnuts to the table to transfer motion, which takes 2 seconds. This deal was to good to pass up, so my funds and time are now 100% on this.

[diyengineer]

Originally Posted by Al_The_Man Did you find out what motors are on there? Al.

Have not taken the servo plates off yet, just finished cleaning the entire machine, gutting the old wires and vacuum hoses, and cleaning, cleaning, cleaning lol. Oh and it took me a few days because i citric acid bathed 14 individual linear rails. They turned out PERFECT

[diyengineer]

These are the current pictures, after i cleaned the entire machine, gutted out the old vacuum hoses, and all of the old electrical wire. I took off 14 linear rails, 7 on each side and acid bathed them for 24 hours. The results were amazing! I will submit a before and after picture in my next post.

I currently need to dig into the gantry. In "Image 9275", The 2 aluminum plates each house a servo on the other side. The left servo connects to the ballscrew via a belt and the right servo connects to the very large black gear which is connnected to a toothed pinion gear that meshes with the linear rails. If you look even closer there are two very large black flat headed screws on the left and the far right. each houses a bearing, one above the linear rail, and one below the rail. The unit has an addition bearing which is in clear plain site (in front of the black gear, below the large gold gear).

My plan is to take out the ballscrew, citric acid bath it for 24 hours to remove all surface rust, re-oil. If possible purchase all new bearings for the ball screw along with the ones behind the black screws and in plain sight. replace and and all old hardware/parts and citric acid bath whatever i come across that needs it. Then repaint entire gantry (since it will be in pieces anyways).

Question though, if i remove the ballscrew and i take the "Ballnut" off will all the ball bearings come spilling out, or are they locked in there?

[diyengineer]

Here is a few pictures before the machine was cleaned, rails acid bathed, and new rail hardware installed (84 bolts).

Monster rust.

[diyengineer]

Bathed them all for 24 hours in a 35 gallon commercial grade plastic trash can. I used 5 pounds of organic citric acid (100% edible) + hot tap water. Wire brushed once after 12 hours, and once again at the 24 hour mark. Towel dried them off, then used compressed air to blow them off, then used a propane torch to 100% dry them. Then applied machine oil to them.

[DIYaholic]

diyengineer,
Some of the surfaces look "discolored", is this a surface staining or is there any pitting? Results look impresive though.
Keep the pictures coming!

Randy,

[diyengineer]

Originally Posted by DIYaholic diyengineer, Some of the surfaces look "discolored", is this a surface staining or is there any pitting? Results look impresive though. Keep the pictures coming! Randy,

The citric acid bath is clear, but when exposed to oxidized metal like rust it turns BRIGHT NEON YELLOW. The bath leaves a hue of yellow on the surface, almost like a light anodized sort of look.

There are some other discolored spots but there is no surface damage at all (pitting), i think its just where the rust left a weird visual stain effect. Pretty impressive results considering the citric acid is 100% organic and edible haha! It cost me about $20 dollars buying it in bulk from the local heath food store.

If all else goes well i will probably break down and pay to get them hard chrome plated or professionally anodized in the future.

[Al_The_Man]

Originally Posted by diyengineer Question though, if i remove the ballscrew and i take the "Ballnut" off will all the ball bearings come spilling out, or are they locked in there?

They will come out if you wind the nut off, the tubes you see are reloading tubes, it looks like someone has taped them.
Carefully save the balls if you take them apart, there may be two sizes that are fed in alternatively when you reload the nut.
Or order new ones if they are pitted.
Al.

[diyengineer]

YouTube- CNC Rebuild Video #1
Just uploaded this to youtube, view in 720P for a better picture.

Thought i would try my Flip UltraHd camera out cause its so small and easy to upload to youtube.

Anyways maybe someone can help me out with ideas on how to get that gear off.

*forgot to mention, the large black gear is not metal, its some sort of ABS like plastic*