Originally Posted by
Grebe
D) in general- the steps are 1) drill a hole slightly smaller than final size 2) insert a thin sleeve into hole 3) insert a special mandrel such that when pulled back thru the hole it expands the sleeve and hole. 4) Ream the hole which will usually be slightly out of round to final size.
On assembly, insert bolt as a tight fit.
E) in some cases and sizes, the same process can be used without a sleeve but with a expanding mandrel.
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Is the sleeve of the same material as the parent metal?
Is the sleeve effectively swaged into place and then reamed, rather than the parent metal?
I have seen something similar using a roller reamer. That is, a process that just swages the parent metal to size.
But have never encountered use of a sleeve.
Note! Not to be confused with roller reamers as used in oil drilling.
Just interested in the process.