Deglazing cylinder - how long should I rub with scotbrite red?
 

After doing some searching, looks like scotch-brite red with soap and water is good method. About how long does it take to deglaze? ...didn't really find anything that said how long to rub at it.

I used a home made tool that held the scotch brite pad so I could use my electric drill to spin it similar to how a hone works.

I went at a slow rpm, something like 200, for about 30 seconds. I used a new red pad for each cylinder.

make sure you get a cross hatch pattern , bout 60 degrees
up and down while it spins , you will see the cross hatch pattern on the pad as it spins

Cylinder on right is one I deglazed and one on left is is off same motor nothing done. did the deglazing with soap and water and pads on hone. Did the up and down thing too. Deglazed one looks to me like light cross hatching somewhat disappeared. Should i have done it dry?


http://forums.pelicanparts.com/uploa...1551270758.jpg

http://forums.pelicanparts.com/uploa...1551270811.jpg

For the rings to seat the cylinder walls need to have a certain roughness factor, or Ra. Different ring packs have different requirements but 15-25 Ra is normal. Machine shops have a simple digital instrument that can measure. In the event that you don't have enough of an Ra, the rings will have a very difficult time seating. You can hit it with the stones on your hone directly provided they are 220-280 grit which they usually are. A dimple or sometimes called a 'grape' Flexhone does the trick as well.

Oh okay... thought I’d read that there was some special stones required to be used on these cylinders...

...yep, that was the ticket. after scuffing with hone. did three or four times only scuffing for a few seconds drill going as slow as it could each time.

http://forums.pelicanparts.com/uploa...1551408984.jpg

That looks rough! You should not hone Nicasil with a stones, if I have understood all the threads here on the subject.

I'm surprised that your cylinders looked polished after using the Scotch Brite. It dulled my down. Again, I used a new piece of Scotch Brite for each cylinder. I could see VERY fine scratches left from the Scotch Brite on my cylinders.

The current technology is to use a VERY fine hone on the nicasil. I have read 1000 grit? But you would have to have an industrial hone and be able to measure the cylinder after using that stone. Personally, I wouldn't use a grape hone on anything I cared about.

+1

Flex Hone is the method my shop uses. Henry Schmidt believes it to leave to rough a surface, but my engine builder is very experienced and has not had issues over the many years working on high end Ferrari, Porsche, and BMW engines.
Fact or Fiction? Engine Hones for Nikasil Cylinders
http://forums.pelicanparts.com/911-engine-rebuilding-forum/163663-do-i-need-hone-2.html