Nikasil Chippage ms460

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Alvareri

ArboristSite Lurker
Joined
Jan 16, 2021
Messages
27
Reaction score
18
Location
Oregon
Well I dove head first into a port job on a ms460 that needed a complete topend. Went the hl supply route and bought a meteor cylinder kits (piston rings etc). However when I went to change the timing of the ports, I was chipping the nikasil like crazy, using carbide double cut bits at 10 on a dremel, even a grinding stone. It would also lift up with very little pressure as I tried to blend it in to the surrounding aluminum. Is there something I'm missing? Should I scrap it and try again; or run it and see- the blending extends a couple mm above the intake port so I'l a little concerned about that but being that it's not in the compression band it should be fine?
Also, looking to try out an Amazon cylinder "Harbot" 52mm kit- I hear it's made in the USA- is that true? Thanks!
 
Be mindful of which direction the bit is rotating when hitting the plating. You want it to cut the plating into the aluminum and not lift it off the aluminum. It helps to change tool angles and the motor direction when possible to avoid lifting. Sometimes you just have to wear away at the plating very slowly: gently with fine grit diamond and a medium to fine rubber abrasive for a final blending. Use bits that run true and centered so they don't hammer the plating, and run them at a speed where there is minimal vibration, speed setting 1 may be needed with slightly off center stones and diamond burrs. I have, when needed, used a finger on my dremel tool to slow the rpm way down to almost 0. I do most of my work with mid to low rpm, rarely ever max or above half.
 
20210317_012912.jpghere is a little shot of the intake port where the nikasil just kept crawling back. And yes the dimpling on the intake is intentional- never seen anyone try it out so I thought would.
TNsawman-
I was trying my best to keep doing a "conventional cut" in machining terms but raising the intake made for a less than 90° approach going from the outside in if that makes sense.
 
Right, go from inside the port, but in the difficult spots I'll use a diamond burr in reverse rotation to avoid lifting. I sometimes lightly wear off the plating from the cylinder side with diamind before cutting from through the port. If your dremel doesn't have reverse, you may want to modify it or find some AC reverser if it runs on AC.

I'd go over that spot thoroughly with this: https://www.ebay.com/itm/Dremel-425...785597?hash=item3ff4402abd:g:WNAAAOSwAqhgJjbM again being conscious of the direction it is turning, focusing more on the plating than the aluminum since the aluminum wears so much faster.
 
Back
Top