Help fitting new cross slide gib on Grizzly 12x36

I removed the old damage gib and had to cut off about 1-3/8" from the thick end. I'm in the process of sanding the gib down to the approximate thickness needed.
I have to remove about .030" I attached the gib to a piece of wood with double sided tape and held that against the sanding belt. It's a slow process as the gib heats up pretty quick. It's cast iron, so I let it air cool between sanding's. When I get close to the final dimension I'll use some bluing to bring things a little closer. Since the gib is tapered, I just have to be close as the adjustment screws will take up the rest. My cross slide has a set screw midway along the length of the slide to prevent any defection during adjusting. If yours has this, remember to remove it when fitting the new gib.
 
Yes, mine has the center screw on the right side of the slide.

Can ya post some pics of what you are doing?
 
Sorry no pics. but it's straight forward. I layed the gib on the belt sander ( my sander can tilt vertically or horizontally). I made a small wooden frame to hold the gib because it get't dammed hot fast. I just kept sanding and trial fitting till I was satisfied with fit. The gib should slide the entire length of the cross slide and stop even with end of the slide at the dial end. The adjusting screw can now take up any slop. (You may have to grind a lip on the large end of the gib for the adjusting screw to grab onto). I tightened the adjusting s screw till there was no more sideways movement. The side set screw is used to take up any forward movement of the slide. Once this is achieved tighten the rear adjusting screw snug without making the slide too tight on the ways. That's it, a little fiddling till you get the right feel. My slide has .0001" movement forward and backwards, according to my DRO
 
Your height should be pretty close and will be about the measurement of the height of the dovetail. Measure from bottom slide surface of cross slide to the underside of topslide. You probably want to measure the distance between dovetails on saddle with dowels. Then place gib on cross slide upside down. Slide gibb and take measurements of those distances between dovetails. That should give you a ruff measurement of what the gibb should be. Depending on the surface from the factory on the gib I would take the material off both side to try and equalize the stress being put on the gib. It will bow you don't want to heat it up on a belt sander. Once you get the gib within acouple thou. You need to blue and scrape it in. It's gonna move all over the place from machining. That's why scraping is the best and final thing.
 
As Cadillac pointed out keep the heat down when sanding that's why I let mine air cool between sanding's. The height of the gib should be close so just grind the sides till it fits. I never bothered to blue mine or scrap it. I don't have scrapper anyways. As I mentioned before, the set screw half way up the side of the cross slide will allow for some adjustment to reduce any deflection in the dove tail.
 
Ok, so I understand that the height is pretty close as is. So I need to sand the sides until what? The gib is as long as the table, so some has to be cut off, so it can be adjusted. Where do put the 2 adjusters? Half way of their limits? I can do the work, I just need to know everything I can ,before I actually start grinding. 4 months to get this one, I can't wait that long for another gib. Measure twice, grind once
 
Next time someone has this problem I would get a mount the new gib and you have a surface grinder and magnetic sign to do it that way. If you don't have a sign, but have a surface grinder mount on a magnetic chuck and raise one end until the taper is then grind it with coolant or at least with a squirt bottle. Another way if you don't have a surface grinder but have a milling machine. Get a piece of flat bar stock of at least 3/8" thick and then mount by drilling holes thru the bar and either use flat head screw counter sink the holes or Allen cap screws counterbore the holes, transfer some holes into gib and drill and tap the gib to fasten it to the flat and them mount the flat and gib in your mill vise and mill it.

Most do not know how to scrape unless they have taken one of my classes or bought my DVD to watch. Or bought a Connelly book Machine Tool Reconditioning that I also sell. You can look at several You Tubet if the shows that will show you how. Stefan G has a great one. He's take 2 of my classes.
Hard to believe you have worn out 2 cross-slides and needed to replace them or the gibs. Does the machine have oil holes ? Does the gib have oil groves? Some pictures would help us figure out the lube issue. Post 4 does not show lube holes or oil grove. We can help you with installing them, but pictures of saddle top would help.

I see on page 37 of manual http://cdn2.grizzly.com/manuals/g4003_m.pdf it says it has ball oilers. but with out oil grooves of oil pockets the oil will not do much. You should have .0005" to .001" slop in the gib fit so you have an oil film. .0001" is to tight. Rich
 
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The original 20 year old gib was fine I think, but the cross slide is a poor quality pig iron and is really brittle. When ya tighten the compound after turning it to a different degree and re-tighten the hold down bolts. It screws up the under side. This has happened twice. So when I ordered the 3 cross slide, I ordered a new gib and chunked the old one. Went to install the new one and or course screwed it up. Here's some pics of the new cross slide.

It has oil holes Red is for the half nut for the cross slide, blue for each side of the dovetail, yellow is where the casting generally breaks apart. I try not to over tighten the 2 bolts, but the casting still chips
DSC00654.JPG
set screw for taking up gib slop in center
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here is teh slide sitting the way it would installed on the lathe. Gib sticks out about 1 ½" or so
DSC00657.JPG
small end, flush.
DSC00658.JPG

So where do I start? Screw in both adjusters half way in their movement and ???
 
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