Is my cross slide gib strip not ground properly?

I'm pretty sure the factory messed up making that gib, it should have been straight not tapered.
Since you have a mill, why not make a new one? Brass is easy to work with and makes a good gib

Mark
 
Last edited:
I don't think I have the tooling to make beveled cuts on long strips. I can make some fixtures- just a bigger project. I'll try the sanding or milling first and may be take on the gib making project when I have some more time.
 
Lets try something else. Assemble the compound on the cross slide. Leave out the gib. By hand, run the compound in and out. It should be free all the way both ways. If not, figure out why, (dry everything, paint one piece allover with felt marker. slide them together till they bind, disassemble and see where it rubbed.)
I there was no bind, put the gib in big end to the back and see what that does. Is the dimple in a position to catch a set screw? If so, put it all together and see if it binds. Check it anyway, even it the hole doesn't line up.
That way you'll know if the gib is the problem.
Exhaust all posibilities before changing anything permanently.
 
@T Bredehoft I will try what you suggested, I should have some free time tonight. However, I did do a couple of those things previously:

1. No stickiness without the gib strip
2. Yes the notch is for the front set screw to sit in that way when the cross slide moves the gib strip also moves with it.
3. I think when I flipped the larger end towards the front of the slide the angles didn't line up. I think the angle on one edge of the gib is different from the other edge so it only wants to go in one way. I'm fuzzy on this so I will re-check tonight.
 
I have read accounts of folks making their own gibs out of steel, brass, bronze, and acetal. So it's very unlikely your gibs are hardened.

Edit: I made the Fignoggle fixture for making gibs and used it to make some brass gibs for my mini mill.
 
That's cool, I'll have to try making one along with a fixture to hold the gib at an angle. I have a few ideas in my head how I'll do it.

If the gib I have is in fact unhardened I think I know how I will mill it. I also want to try grinding it with the fixture I started building for the belt sander. I need more bad gibs to play with lol
 
stioc said:
I need more bad gibs to play with lol
Click to expand...
You could always make your own "bad" gibs :big grin:

BTW the fignoggle gib-fab fixture holds the gib at an angle so it's easy to get the parallelogram shape. But that moves the problem to milling the properly-angled slot in the fixture. To make mine, I made a 34 degree angle block, put it in my angle vise and used a DTI to adjust the vise angle. Once the DTI needle stopped moving I knew I was good to go (I'd NEVER trust the protractor scale on a cheap imported angle vise).

If you've got a sine table and gage blocks, you've got it made in this regard.

When I made my version of the gib holder, I moved the hold-down screws to the other side of the slot. Reason: I thought the forces on a half-finished gib could make it "tip" over. The one drawback: you have to make sure the screw heads clear the top of the vise that's holding the fixture.

To avoid marring the gib, I put some brass shim stock between the gib and screws.

The drawing for the Fignoggle gib holder is in their free plans section. You can't download it but you can print it.
 
OK guys. So here's what I did yesterday. I decided to use a Dremel type grinding stone on the mill but in order to do that I had to hold this thin gib strip flat and supported but also open at the top. I don't have a magnetic vise/chuck but I do have those cheap Harbor Freight magnetic tool holders. I put that in the vise on top of a pair of parallels, then indicated off the edge of it and then laid the gib strip on top. This was surprisingly secure, in fact, in the end it was almost impossible to remove the gib strip but I was able to slide it off. I also used the sander.

298195

298193

298194

What worked and what didn't work:

1. The small grinding stone was dissolving way too fast to be trusted to create a flat surface. Next I tried Roloc as I didn't have anything else.
2. The Roloc even the most aggressive 100 grit pad left a fantastic finish (very polished) but wasn't removing material fast enough. It also wasn't digging into the material when I moved the z-axis to say .01" at a time because of the soft pad material. Lastly it generated a lot of heat into the part so hopefully I didn't work harden the gib strip. So this would work great for a polished finish (or removing rust/milscale like it's usually used for) but not so much for sanding metal.
3. The belt sander removed material the fastest. I'm sure if the jig could be refined to use a magnetic slide or something it would work fairly well. In fact, knife makers on youtube seem to use something similar quite successfully as a poor man's surface grinder.

The end result? It worked. I can now run the slide all the way to the back and to the front very smoothly and evenly using the handwheel (which btw sucks due to it's poor design but that's another story). No play in the cross slide when I tugged on it while in both extreme in and out positions so I'm very happy with the results.

Thanks to everyone for your help and suggestions, hope I provided some entertaining value here if nothing else :)
 
That's some clever usage of what you've got on hand!
 
You must log in or register to reply here.
Back
Top