filling holes on aluminum

slow50 · Sun Nov 20, 2011 4:40 pm

im self taught at tig welding and i got aluminum down pretty good. whats the best way to go about filling in a hole? for example on an aluminum cylinder head when a stud gets striped out and the hole is too large for a heli coil the only option is to fill it in the drill and tap. some times the holes are about an inch deep and about 1/2 inch diameter. also any tips on welding dirty aluminum like cylinder heads? i usually clean the grease then glass blast it then wire brush. thanks for the help.

slow50 · Sun Nov 20, 2011 4:41 pm

oh ya and some times the holes go all the way through theres no bottom and sometimes you cant get to the back side.

pro mod steve · Sun Nov 20, 2011 6:20 pm

Don't know as far as welding but I think loctite made an aluminum thread repair kit that worked like jb weld a paste solution. Don't know about the strength though.

red racer · Wed Nov 30, 2011 1:11 pm

Filling holes is a real challenge some times. Try beveling the hole as deep as possible,I know you have to deal with water jackets, and all other restritions. I have to deal with this situation from time to time. I have thought about this fix. If you have room around the hole.Drill the hole bigger , and take a piece of aluminum dowel,bevel the hole as much as you can incert dowle & weld around the dowel filling the bevel .Then drill new hole ,tap/helicoil.......This would take away trying to reach to the bottom of the hole with weld ......Just an idea i've been thinking of trying.R/R

slow50 · Wed Nov 30, 2011 7:59 pm

thats a good idea. if im understanding right you wouldnt be able to weld the dowel solid right? just about the top half depending on the bevel.

red racer · Thu Dec 01, 2011 1:03 am

Correct: you would have to get enough beveled out to hold all the stress from the torqueing of the head bolt. Thats for the blind hole repair. For the through hole,you would weld both ends of the dowel, with as much bevel as possible also ,just to be safe.Even if you got into the water jacket the dowel ,being welded good and solid shouldn't be a problem. I have done this type of repair on electrode clamps for electric arc furnaces. Water cooled jackets...but they were all copper...but thats another story............................

R/R