rebuild again, does Nikasil go bad? |
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rebuild again, does Nikasil go bad? |
worn |
Dec 27 2015, 07:03 PM
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#1
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can't remember Group: Members Posts: 3,156 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Saw a thread on the Pelican site showing a set of delaminated Nikasil cylinders. After cleaning up mine I see a few pinpricks. Cylinder 5 is by far the worst offender with what looks not so good to me. Would value response from those who know. I recognize that no 914 came equipped with them.
Longer view Closer up Would you be worried? Reusable? Thanks!! |
Mark Henry |
Dec 28 2015, 08:39 AM
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#2
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Simple test feel the top ring ridge, if you feel a rolling ridge (opposed to a used steel cylinder's harder, sharper ring ridge) then you should have it replated. If unsure you should have it checked with a bore gauge.
Very high milage cylinders will begin to fishmouth, meaning the top of the bore will be bigger than the bottom. A few small pits in nikasil is normal and OK. Delamination looks sort of like chrome has flaked off a bumper and needs replating. |
worn |
Dec 28 2015, 10:12 AM
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#3
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can't remember Group: Members Posts: 3,156 Joined: 3-June 11 From: Madison, WI Member No.: 13,152 Region Association: Upper MidWest |
Simple test feel the top ring ridge, if you feel a rolling ridge (opposed to a used steel cylinder's harder, sharper ring ridge) then you should have it replated. If unsure you should have it checked with a bore gauge. Very high milage cylinders will begin to fishmouth, meaning the top of the bore will be bigger than the bottom. A few small pits in nikasil is normal and OK. Delamination looks sort of like chrome has flaked off a bumper and needs replating. Thanks Mark. Initial measurements were very encouraging but I haven't run the mic that way. When I washed them there was no perceptible ridge. |
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