Rulon vs new gibs

LEEQ

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I'm in the midst of a learning experience putting together a Bridgeport mill. They utilize tapered gibs that can be had for about $150. My machine is worn to the point that the gibs don't fit. Of course new, they will need to be fitted as they come oversized to allow for wear. I could grind the old ones a little and add wear strips of rulon instead fitting them that way. As I understand, this scrapes very readily. Every time I try to price rulon type material, I am faced with what seem to be very high prices. Unless I'm missing a lower priced place to purchase rulon, it appears to be cheaper to replace the gibs with new and fit them. Utilizing rulon only if I have to, to restore alignment of the leadscrew, brackets, and feednuts. Replacing metal lost to wear on the saddle. Are there benefits to using the more expensive route that I am not taking into account? Also, where are good sources for this type of material in sheet form? Another brand is spelled turcite I believe. Thanks in advance.
 
What kind of prices are you coming up with?

Bernie
 
I did some searching and had better luck on search results as far as sources. As far as prices, McMaster Carr has a 6"x6"x1/16" piece for $43. Better than I remember finding. I didn't call any of the others yet. They want to quote you a price. They offer better options dimension wise though. 12" or 24" wide rolls. no minimum. I would rather use a piece too large than piece it together. Wish McMaster Carr had long skinny gib type options. Who did you go with Bernie?
 
Did you slide in the old gib and use a feeler gage to figure out what thickness Rulon to use?
Slide it in so the top of the gib is even with the big end.
I can sell you some. If I know the thickness you need. I buy it by 12" wide x 36" lengths.

Rich
 
I'll have to do some figuring out. I think the needed thickness is closer to .015 on one, .012 on the other.That's a little thin isn't it? I think I'm replacing the table gib that was stretched out with brass/brazing. Should that new one be fit without fancy wear strip? Maybe a little machining before the wear strips are added? Thank you for your very generous offer on the material. I was hoping to have the building up figured out and done before getting hands on pro help ironing this out.
 
I've been thinking.

You do know that the ways are no doubt worn and just shimming the gibs will not cure the wear issue. The top knee is no doubt worn in the middle and the table is bent high in the middle and worn. The back of the knee worn. You can help it, but when you adjust the gibs right they will bind on the ends. You can't use Rulon on the backs of Bridgeport gibs as the locks against the back, so the rulon will squish and get damaged. They do make a .015" Rulon and you could glue it to the front side, but if you scrape it, it will be super thin and hard to cut oil grooves in it. It as it is expensive and using it on a "fix" would be a waste of $. Now there are a couple of other alternatives you can use. Probably the cheapest way would be to buy some stainless steel shim, cut to fit the back. You will have to cut a groove in it so the oil could transit it to the ways. Another method would be to buy some .015" Linen Phenolic and glue it to the back, it's pretty cheap. Or grind off the face of the old gibs and glue it to the face. I would use a minimum of .032". Or use Rulon .032". Lately I have been using Loc-Tite 380 5 minute super glue on fix's. It will work on all the above methods. You can use J/B Weld, but I don't use it anymore.

You probably have a Place near KC that sell Phenolics (canvas or linen grade, never paper). Up here I use http://www.precisionpunch.com/matindex_phenolics.html

Check into a local company who sells it and let me know. If your not going to scrape the ways why spend the bug bucks on Rulon? I have been using Phenolic on gibs for years and on the wear surfaces on lathes, mlls, grinders. It's not self lubricating like Rulon, but for a fix on a Bridgeport it will work!
 
I do want to scrape the ways and restore alignment for sure. That way things are true and the leadscrew and saddle screw sit right in the machine. The wear has created issues with fit of things. Also the table is new to me and has less wear, but was not fit to this machine. I want the table to traverse end to end without change in fit/getting tight. My hopes were to have things built up already in preparation of scraping. I was wondering about the locks pressing against the plastic also. If I just get a new set of gibs, problem solved. there will be enough material to fit them and no question as to wear from locks. That would leave only building up the saddle and maybe knee to restore alignment of screw brackets to feed nuts, right? I'm not sure the top of knee will even need it. It still shows scraping if I can live with and maybe disguise a couple deep grooves I don't think that the knee top needs scraped down very far. I'm open to using cheaper more readily available material for the build up also.
 
The gib on the cross slide of my lathe is about worn out. I'd like to try a rulon shim (I've already scraped away the high spots at the end of travel due to wear in the middle).

What keeps the Rulon attached to the gib? I experimented with a brass shim and the brass would slide out when I moved the cross slide as the gib badjustment screw doesn't bear all the way to the insode of the gib. I would imagine Rulon would be even worse... I can't image any type of adhesive that readily sticks to Rulon.

John
 
One side of the Rulon is acid etched or dipped in acid that eats away the layer of the slippery material and the epoxy wicks into the open pours. I have been using the Loc-Tite 380 Black Max super glue and you will be shocked to how difficult it is to pull off the Rulon. I did a test on some iron and it blew me away. You will need to glass bead blast (sand blast) the gib so it resembles 200 grit sand paper. I have also scratched the heck out of the surface with the coorner of a hand or power scraper. Many times I will heat the gib or cast iron up to about 400 degree's to sweat out the oil that has penetrated the cast iron. Before you apply the epoxy or super glue, spray the material and cast iron with fast dry electrical cleaner or brake cleaner.

PS: Slide in the gib and check how much shim is needed with a feeler gage. Slide the gib in to where it goes when it's at the top of the adjustment and the feeler gage is tight.
 
don't get a new gib if you don't know how to scrape you will screw it up , epoxy some backing on the old gib and you are back in business. I know i have scraped machine and if you don't have the equipment you will screw it up
 
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