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JimN
09-30-2012, 01:54 PM
I have a 6" jointer and last week, I was going to clean & wax the exposed surfaces to get it ready for winter and because it was due. When I removed the cover, I saw a 2" crack in the leading edge of the in-feed table. Nothing has fallen on it and it sits under my 12" disc sander's shelf, as well as my stored lumber.

I'm thinking that I can stop the crack by drilling a hole, threading it, spin a bolt with Lock-Tite, cut it off and file it flat. That doesn't do anything for the crack, itself. Can this be repaired using a TIG welder? I don't have one, but I'd like to know in the event that I find that I know someone who does.

Thanks.

CantRepeat
09-30-2012, 02:05 PM
I have a 6" jointer and last week, I was going to clean & wax the exposed surfaces to get it ready for winter and because it was due. When I removed the cover, I saw a 2" crack in the leading edge of the in-feed table. Nothing has fallen on it and it sits under mt 12" disc sander's shelf, as well as my stored lumber.

I'm thinking that I can stop the crack by drilling a hole, threading it, spin a bolt with Lock-Tite, cut it off and file it flat. That doesn't do anything for the crack, itself. Can this be repaired using a TIG welder? I don't have one, but I'd like to know in the event that I find that I know someone who does.

Thanks.

I have a TIG and MIG but neither is good for cast iron repair. The method most commonly use is SMAW or stick welding. Pre heating is very important.

Lincoln has nice write up on it.

http://www.lincolnelectric.com/en-us/support/welding-how-to/Pages/welding-cast-iron-detail.aspx

I have also seen cracked cast iron heads repaired in the manner you are talking about for stopping the crack. What they do is drill and tap then screw in your bolt(plug), cut it off and then drill next to that bolt but also into part of that bolt. They do this through out the crack itself.

This is the one type of plug for cast iron.

http://www.goodson.com/Cast-Iron-Crack-Repair-Plugs-Sizes-from-.200-inch-to.590-inch

You should be able to find them in less quantities.

JimN
09-30-2012, 02:39 PM
I have a TIG and MIG but neither is good for cast iron repair. The method most commonly use is SMAW or stick welding. Pre heating is very important.

Lincoln has nice write up on it.

http://www.lincolnelectric.com/en-us/support/welding-how-to/Pages/welding-cast-iron-detail.aspx

I have also seen cracked cast iron heads repaired in the manner you are talking about for stopping the crack. What they do is drill and tap then screw in your bolt(plug), cut it off and then drill next to that bolt but also into part of that bolt. They do this through out the crack itself.

This is the one type of plug for cast iron.

http://www.goodson.com/Cast-Iron-Crack-Repair-Plugs-Sizes-from-.200-inch-to.590-inch

You should be able to find them in less quantities.

That's what I hate about cast iron- it needs to be seasoned before machining and there's still no guarantees that it won't do something stupid.

I'll call a local machinery dealer- he has a really good repair machinist.

Thanks.

NatesGr8
10-01-2012, 10:49 AM
Heat Heat Heat w/ cast iron. You're on the right track going to a repair machinist. They deal with this stuff more routinely.

JimN
10-01-2012, 02:27 PM
Heat Heat Heat w/ cast iron. You're on the right track going to a repair machinist. They deal with this stuff more routinely.

I'm trying to get this done without putting the infeed into a furnace because it will need to relieve the stress all over again, ground flat and make sure it's not twisted/expanded/contracted, etc. If it warps, the whole thing is crap because the machined ways need to line up and everything needs to be level.

I went to the local place a couple of years ago to see about having a Lurem spindle shaper (discontinued and the company was sold) repaired and the machinist did a nice job- the motor shaft was all boogered up and needed to have a new end made. It worked well enough for the buyer, so....