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Author Topic: Needing info on Nikasil  (Read 143 times)

Offline broken1

Needing info on Nikasil
« on: November 04, 2018, 12:33:02 PM »
My friend sent his YZ cylinder out to get repaired & re-coated. It needed to have a couple spots welded up but it looks like the place that did the repair didn't build the weld up enough so when they bored & re-coated the cylinder it left little pin holes in the coating where the weld repairs are. He talked to the guy that made the repair & the guy said if he try's to weld it more so there's no pinholes that it will make it worse.  I don't know anything about nikasil or nikasil cylinders so I wanted to ask your opinions. Are the pinholes going to cause any issues? Thanks for any help.
overkill is an often underrated achievement

Offline The norm

Re: Needing info on Nikasil
« Reply #1 on: November 04, 2018, 02:13:27 PM »
Kevin,  can you send me a picture? I will text it to Pete and see what he says. I'm going to guess that the pin holes are because of the crater that can be left when tig welding aluminum. If you just snap out of an aluminum weld it will leave a divot at the end of the weld. That divot usually cracks. You have to ramp down the amperage and kinda do a little swirly thing with your tig torch to prevent it.
« Last Edit: November 04, 2018, 02:19:40 PM by The norm »
I had a BDT motor once.....It SUCKED!
Currently: Hybrid Engineering 310 stroker built by Pete