Cracked Gib!

....snip......

its tapered and has keyway along the top of the non tapered edge I'll have to get a picture next time I'm at the machine.

I'll do looking in my collection of gibs. I may have one close enough that you maybe able to modify to fit.

Please post some pictures, sure help on getting you fixed up.

Ken
 
I'll get some pics up as soon as I can I just got impatient and figured id make a thread :p maybe I can get someone to send me some pics as I live in a different city from where the machines are :(
 
Is the gib still in one piece? If so, maybe just leave it alone. Maybe drill a stop crack hole in it and use it as-is. Replacing a tapered gib is NOT just buying an off the shelf gib and swapping it out. It won’t happen that way…nada. You will have to make it or modify one. And I just made one out of 12L14 (I think the lead in it will help) for a Levin cross slide. Works like a champ. It would be a REALLY good thing to have a surface grinder for this job…Dave
 
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Back in the days of machine tool repair, we had a shop make our gibs for us. They would buy a slab of cast iron of a determine thickness, usually about two foot square and about 1" to 2" thick. In fact, they kept several thicknesses of cast iron plate on hand just for gib making. They had a smaller openside planer in house that they used for this so they didn't tie up the "beast" for real planning jobs. Took a part off tool and would rip off pieces of varying thicknesses with a taper that matched closely with the original. Once that was done, they set up a angle fixture that was a magnetic chuck and start working the angles until the gib shape was made. Next it went to the machine component the gib was made for and the master scrapers fitted the gib to the slide. Last, the gib was cut to the necessary length and gib screws fitted to the gib and slide.

Just from my own experience, if you use a surface grinder, you will have a problem with the gib warping on you. It takes lots of flipping from one side to opposite side, doing this many times taking only a thousandth or less to keep warpage to a minimum. I find it easier to set up on the mill with a fly cutter or inserted face mill that uses a high positive insert to mill the faces of the gib. You still have to leave material and take same amounts from opposite sides to get the warpage to go away. But with the face mill it tends not warp as bad as it will on a surface grinder. Making a gib out of steel is common, but I prefer cast iron. It's much easier to scrap than steel is. And don't use brass or bronze for a gib. Ken
 
Is the gib still in one piece?
Yes it's still one piece but just barely I thought about stop crack drilling it but didn't know if that was acceptable on this part maybe I could do that along with Brazing to get me by until I can get/make a new one!
@4gsr the only machine tools I have is my birdgeport mill and my McKenzie lathe I do know some places locally that could do surface grinding if it was absolutely necessary and I've been really curious about the scraping process maybe this would be a good starting point for me to learn? Start small and work your way up right? :)
 
Brazing it IMHO does not sound like a good idea. It will take a lot of heat to do that. And so you could warp the part with all that heat. And then your gib would be just about useless. Or need to be reworked. It’s a chance I would not take. I would stop the crack and just use it. How did it crack in the first place? Did it crack on its own? Maybe from internal stresses? What do you think all that heat would do to those existing internal stresses?….Dave
 
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Izzy,

I found a gib that matches your description stated earlier. It's probably much bigger than the gib you have on hand. About 5/8"- 11/16" thick, 1" wide at the biggest end and about 12" long. If you want it, pay the pay the postage and it's yours.

Ken
 
That would be awesome! Could you send me a picture? Also I'll be at the machine on Christmas (yea I know not so convenient for everyone else) I'll be able to get pictures of mine at that point.
 
I'll take some pictures and post

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