Thread repair in magnesium?

[johns cubs]

I loaned my chainsaw to a buddy and he must have over tightened the bar mount bolts. The threads in the saw are pulled right out! Was wondering if anybody has ever had this problem and if any of you have tried JB to repair stripped out threads? Think I am gonna try it cause looks like only other option is to take to a welding shop and have them fill the holes and then redrill and retap, but would probably have to strip the saw down and split the case and I really dont want to have to do that, again! I just had the saw all apart to rering it and while I had it apart i ported and pollished the cylinder and nade a muffler mod. Saw screams now but i broke my own rule of lending it out!

[Sam Mac]

Can you put a heli coil in it?

[ol'George]

Many years ago when dirt was new, I made it a rule not to loan out my girlfriend or my tools.
they just never return in the same condition.

[Yosemite Sam]

If the walls of the hole/s are thick enough, heli coil is gonna hold much better than JB Weld.

Can you find someone to weld magnesium?

Might be best to get a new case.

[Alvy]

I was told you can't weld magnesium because it creates it's own fuel source when it burns and you can't put it out but I may have heard that wrong

[J-Mech]

Not many places will weld Magnesium. It's a pretty specific thing to weld.

You sure it isn't aluminum? They look identical.

What kind of saw is it?

[Terry C]

Is it a bolt or a stud that threads into the stripped hole?
A Helicoil works good if it's a stud. If it's a thread that gets loosened
and tightened a lot I don't recommend Helicoil. Helicoils tend to work
themselves out of a hole if it is loosened and tightened often. One time in and
tight they work great.
JB not going to hold a bar on a saw.

[DoubleO7]

file a spot bare naked.
Squirt some vinegar on the spot.
The mag will "fizz" where as nothing will happen on aluminum.

[johns cubs]

Originally Posted by J-Mech

Not many places will weld Magnesium. It's a pretty specific thing to weld.

You sure it isn't aluminum? They look identical.

What kind of saw is it?

Its a chraftsman built by husqvarna in the mid 80's. I just had the engine all apart and rebuilt the thing, rings, gaskets, fuel lines oil pump, new clutchand sproket, ported and polished the cylinder..I tried the JB to no success, I made about 4 cuts yesterday after letting the jb cure and it seemed like i got a good squeeze on when tightend it down but did not last. Once it heated up they pulled loose.

Gonna look on line and see if anyone may have parted one out. And just buy the half of the case i need.

I am only into the saw for about 60$, thats with the rebuild! And i love the saw, i have a husq 445 x-torq, a Echo 440e and some older sthils and that thing will cut circles around all of them. My wife works for asplundh tree services and can get me a new husq 372 xp for about 500 so if i can get this thing to hold up til after chraistmas I see orange in my future!

[Sam Mac]

Post a pic of the problem area so we can see what your trying to deal with.