I need magnesium welded or a case half

[Yotaismygame]

This 084 project is going to require a little magnesium welding or a replacement pto side case half. I'm already into this saw a little more than I want to be so buying a half isn't the preferred option unless it's cheap. There's nothing wrong with the case half I have except where the inner spike bolts to the top of the case. It's very fragile and cracked. Looks like the center pulled out as well. I already went to a machine shop I like doing business with and they didn't think they could do it. JB weld? I was thinking of having the hole welded up and then drill/counter sink it for a bolt to pass through.

 

[cuinrearview]

@srcarr52 is your man

 

[Yotaismygame]

Does he hang around here at all or do I need to contact him on the other site?

 

[cuinrearview]

Does he hang around here at all or do I need to contact him on the other site?

I think he checks in. It doesn't look like my @ is highlighted so I'm not sure if he'll be tagged on this thread.

 

[Yotaismygame]

It’s supposed to look like this

 

[RedneckChainsawRepair]

I think he checks in. It doesn't look like my @ is highlighted so I'm not sure if he'll be tagged on this thread.

It tagged him. Just their new way.

Looks the same as rest but link is clickable too. @srcarr52 see

 

[Snowchaser]

If the spike side is flat, you could cut a 1/16” or 1/8” steel plate and drill and tap 4 or so #10-32 bolt holes to secure the plate, then space the bottom mount with a flat washer or two. Should still be plenty strong. Not sure what the back side looks like though.

 

[Yotaismygame]

I contacted Sean. I'll look into making a plate when i get home. I like the idea.

 

[Snowchaser]

Epoxy the plate on too maybe.

 

[Yotaismygame]

I'm wondering now if I could just drill a new hole farther up. The spike looks like it extends high enough. And if not I could just add to the spike. Would end up using three points to attach it. The bad side of the case is pretty flat above the oil tank.

 

[srcarr52]

I only get an email when someone PM's me. I charge $35 plus shipping to fix a Stihl upper spike mount barring it's not missing more than normal.

 

[Ted Jenkins]

I tried to weld some magnesium cases a couple of years ago and it did not work well. I tried heli arc, mig tig and gas was very disappointed. The more pure aluminum welds easy peasy. Will want to see how well this works. I have a gas chamber to pump out oxygen and fill with argon, but it not super professional and it takes a long time to get every thing set right, so used a little welding with JB weld. Thanks

 

[Huskybill]

I tig welded magnesium clutch covers and engine cases on husky dirtbikes. The metal needs to be squeaky clean. I setup a cardboard box on my acorn table, opened up the argon in the box eliminates all the oxygen. I got some magnesium tig rod samples from my vendor. My only problem was when some welding droplets fell through the squares in the table they caught fire.
Of course the reaction is to step on one burning droplet. Being new at it I had six Richard Pryors on fire running across the floor. I just let it burn out after that.

 

[trappermike]

For one thing crankcase halves are usually finish-machined together so the match perfectly,using a half from one motor to another may mean bad crank alignment,cyl. surface uneven etc. They are always recommended to be replaced as a matching pair,but some people get away with mis-matched halves.
As for welding magnesium ,I have not seen anyone able to do it well without risking destroying the part in modern times with modern equipment,if any modern welder brags he can first bring him an old piece of magnesium to weld,see if he succeeds before you cook your saw part. But in the 80's in our saw shop we welded broken or cracked magnesium all the time successfully,but we used oxy-acetalene,magnesium rod and a jar of special flux. It took some practice,but once you got it flowing it is almost like brazing(brass) with acetylene. The oldtimer who taught me just had me bust some old magnesium parts,then weld them together for practice.
I suppose no one has acetylene welding skills anymore,I also did all the aluminum welding on saws (mostly handlebars) very well with acetylene also.

 

[Huskybill]

When I was working I took on the welding and fabrication as well as the lead engineering tech, r& d development . In my welding department I took on every welding job that most thought was impossible. Just to learn more. Welding magnesium was one of my favorites. I tig welded all magnesium cases. We had a certified welder before me. He was certified in all types of welding and cutting even under water. He knew he was leaving the job but before he started giving me crash courses on all the welding processes. While I was going to school for welding.
You can be as good as you want to be just apply yourself and stay motivated.

 

[trappermike]

Well I figured someone should be able to weld magnesium with all this new technology,just I'll believe it when I see magnesium welded well today. Most of these guys SAY they can,but I'd give them a junk part to weld first...see how it looks...

 

[trappermike]

Of course a professional guy like you can do it,but you are hard to come by,any welding shop I go to locally will say they can,and I know the results.

 

[grizz55chev]

Of course a professional guy like you can do it,but you are hard to come by,any welding shop I go to locally will say they can,and I know the results.

You are correct about using miss matched cases, not the best idea.

 

[trappermike]

You are correct about using miss matched cases, not the best idea.

Once I was forced to do it,when I put the crank in it would immediatly turn to one side hard when you turned it,obviously mis-aligned halves,cyl. surfaces didn't match,was a colossal waste of time.

 

[grizz55chev]

Once I was forced to do it,when I put the crank in it would immediatly turn to one side hard when you turned it,obviously mis-aligned halves,cyl. surfaces didn't match,was a colossal waste of time.

I had one that went together like butter, ran like a champ, for about 1 tank of fuel. After that it had a squeal that I couldn’t find, tried for weeks to fix it, finally parted it out.