Fitting a shaft to a distributor

[Ed in Maine]

I am restoring a distributor. I have pressed in the two bushings and now I want to ream them to the proper inside diameter. I miked up the shaft from Snyders and it is 0.501. My questions are:
1. This isn't the only distributor I plan to rebuild. I like doing things for my fellow club members. Should I get an adjustable reamer? I am worried that some shafts could be smaller or larger in diameter.
2. If I purchase a fixed reamer (they are cheaper), what diameter reamer would you buy for this shaft?
3. What industrial supplier will provide a quality reamer?


Thanks for your help, Ed

[rotorwrench]

A fixed reamer for a specific size will result in a better finish. The fit depends on the reamer. I've used adjustable reamers a lot over the years and my best advice is to start small and slowly expand with each pass. They have a tendency to dig in & chatter if a person tries to take too big a bite at any time in the process. A fixed reamer that starts with a bit of taper and ends at the finish size is quick and easy to use with no adjustments necessary but it will only be good for the size it was made for. These generally have many spiral or strait flutes and are the only way to go for precision work. With either type, always use lots of grease or oil then clean & relube them with each pass. Some folks use a Sunnen hone but the caveat with them is that they tend to leave microscopic pieces of hone stone material embedded when honing soft metals like phosphor bronze. This may cause premature shaft or bushing wear in operation.

A finish clearance of .0015" to .002" should be as good as it gets. A person has to have some clearance but too much can cause dwell time problems with the breaker points.

[JKY]

Originally Posted by rotorwrench

A fixed reamer for a specific size will result in a better finish. The fit depends on the reamer. I've used adjustable reamers a lot over the years and my best advice is to start small and slowly expand with each pass. They have a tendency to dig in & chatter if a person tries to take too big a bite at any time in the process. A fixed reamer that starts with a bit of taper and ends at the finish size is quick and easy to use with no adjustments necessary but it will only be good for the size it was made for. These generally have many spiral or strait flutes and are the only way to go for precision work. With either type, always use lots of grease or oil then clean & relube them with each pass. Some folks use a Sunnen hone but the caveat with them is that they tend to leave microscopic pieces of hone stone material embedded when honing soft metals like phosphor bronze. This may cause premature shaft or bushing wear in operation.

A finish clearance of .0015" to .002" should be as good as it gets. A person has to have some clearance but too much can cause dwell time problems with the breaker points.

That's great information. Thanks for posting it.

[Roger V]

I have encountered odd dimensions and thought to use my expansion reamers. BUT, in the case of a distributor, the only reamer I use is an "alignment" reamer. Just like kingpin bushings, using a regular reamer is likely not going to be in alignment but cocked. You ream both bushings until the shaft goes all the way through but you're touching on only a part of the bushing. Then it wears quickly. Find a correct dimension shaft or if larger, turn it down.

[chrs1961815]

I use a hone. The bushings are usually .5 inches ID. I like the finish a hone does, reamers are quite rough. It doesn't take much.

[Tom Endy]

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Here is how I do it.

Tom Endy

http://www.santaanitaas.org/wp-conte...Techniques.pdf

[Russ/40]

I cant get the link to work?

[Tom Endy]

Originally Posted by Russ/40

I cant get the link to work?

Go to the web site of the Santa Anita A's of Arcadia, California at www.santaanitaas.org. Click on Tom Endy's articles.

Tom Endy

[Dan McEachern]

" Some folks use a Sunnen hone but the caveat with them is that they tend to leave microscopic pieces of hone stone material embedded when honing soft metals like phosphor bronze. This may cause premature shaft or bushing wear in operation."


It's my opinion that this statement is unfounded and more than somewhat inaccurate. Take it for what it is, but literally millions of wrist pin bushings have been and continue to be pin fit using Sunnen hones with what I consider to be excellent longevity. Suppose we are all entitled to our opinions.

[rotorwrench]

I use a reamer for wrist pins on the Harley Davidson rods but it has a bore guide that keeps it aligned to the cylinder base pad during the cut. I can do them without splitting the case that way and they come out perfect every time. I use a hone on the steel parts or I lap them with special lapping tools.

I didn't say you shouldn't use the Sunnen on soft metals but do it and then put them under an electron microscope and see what's left. I'd brush it good with a soft bristle bottle brush and soap & water before putting it together. At least that will minimize any left overs.