Chainsaw Repair

Was wondering if any of you have any experience with taking say 10mm small rod end and boring it to say 12mm or taking a 12mm to 13mm etc?

What type of machining would be involved?

Have a friend that faced a similar situation. He solved it by cutting the con rod and welded a 12mm small rod end on in place of the original 10mm one.

Saw the welded rod. He ran it for 5 races before it failed. Stihl 026 base. Big Poulan topend. Not far behind my TW 260.

I've got a theory ,never tried it but it might work .You'd have to be darned good with a lathe but it could be done .

A milimeter is 39 thou .In the case of 10 to 12 mil  that would be approx 78 thou diff .So if you made a blind end bushing that pressed in the piston with a hole in it about the size of the hole in the pin so it could get oil it might work .You'd have to either cut the pin a tad shorter or find a pin a tad shorter to allow a flange like thing with enough meat to hold the circlip .Now I have no idea if an aluminum bushing would hold with a circlip or not but the flange would  hold the pin in place .

In the case of 12 to 13 mill that would only be around 18 thou wall thickness for the bushing .Might work,might not .

If I had my Monarch 10" EE running and I was in the right frame of mind I think I could cut some out .Trying to run that tight of tolerences is a beech though . To work properly the fit would have to be tight else the thing would fly apart like a dollar watch .