Tread chaser or thread size

T

Twocollies

Junior Member
I'm looking for a thread chaser for the cam shaft end, or can some one tell me what the tread size is. The end was clinched when the original camshaft nut was peened with a chisel. I don't want to force the new cam nut over the damaged threads.
 
If it is just the threads at the end get a small triangle shaped file and chase the thread from just below the damaged area and work your way out towards the end.
 
Re-threader files are available and come with numerous thread counts and pitches. This could be a place where you could use one.
 
You can make a chaser by making 3 or 4 cuts in the threads of an old nut with a hacksaw. All cams and/or nuts aren't exactly the same. I use 1 nut as a starting chaser and a different nut for the final, if needed. Find the ones needed by trial and error.
 
Jim Brierley said:
You can make a chaser by making 3 or 4 cuts in the threads of an old nut with a hacksaw. All cams and/or nuts aren't exactly the same. I use 1 nut as a starting chaser and a different nut for the final, if needed. Find the ones needed by trial and error.
Click to expand...

Haha, Easy for you to say. Not everyone has a box full of cam nuts.
 
The Master Cylinder said:
Haha, Easy for you to say. Not everyone has a box full of cam nuts.
Click to expand...
But everyone who is replacing the cam nut has at least one.

Interesting anomaly. You buy the new nut AND you buy the wrench from one of the mainline suppliers. Both from one house.

The wrench doesn't fit the nut.

I took the nut as being made to a Ford drawing, and modified the wrench with a file.

This something I could see happening. The wrench is TOTALLY aftermarket. Somebody has a wrench design, makes them for fun and profit, and may have a manufacturing issue develop unbeknownst. Rinse & repeat. It happens all the time in business, especially when quality is not formally controlled.

BUT - You would think that someone would be curious enough to at least TRY the two components together - lest there be some issue that gets returned?

Most buyers probably don't have a drawer full of files, and may not have the skill to use them properly.

Joe K
 
Joe K said:
But everyone who is replacing the cam nut has at least one.

Interesting anomaly. You buy the new nut AND you buy the wrench from one of the mainline suppliers. Both from one house.

The wrench doesn't fit the nut.

I took the nut as being made to a Ford drawing, and modified the wrench with a file.

This something I could see happening. The wrench is TOTALLY aftermarket. Somebody has a wrench design, makes them for fun and profit, and may have a manufacturing issue develop unbeknownst. Rinse & repeat. It happens all the time in business, especially when quality is not formally controlled.

BUT - You would think that someone would be curious enough to at least TRY the two components together - lest there be some issue that gets returned?

Most buyers probably don't have a drawer full of files, and may not have the skill to use them properly.

Joe K
Click to expand...

I'm thinking you need more than one for a "trial and error" fit, no?

I just buy the "modern" style cam nuts and use a 1½" socket on it and call it a day.
 
These threads are 16 threads per inch. Snap On makes a very nice thread chasing kit that has thread files for the various pitch of threads.
Dave
 
Most chasers have four pitch sets on each end for a total of eight different pitches. They are handy to have for both Unified and Metric. I have those and British Standard and Association. When you repair and restore things, you can never have too many tools.
 
Here is a good source for two piece thread chasers. They sell them individually or in sets. Great company to deal with. Supergnat
 
No sure why the link I sent disappeared. The company is JME Supply LLC located in Ohio. It is a small veteran (John) run business that specializes in rethreading dies It was recommended to me by someone at the Thread Tool Supply Company in Wisconsin since they did not have the size I needed (5/8-18). You should be able to Google either of them to get information.
 
The thread on the camshaft is special for an interference fit of the nut. Commercial thread chasers will ruin it. Use Jim Brierly's suggestion of a thread file to fix it.


As for the availability of a camshaft nut, one should look at a parts catalog. Bratton's has the nut for less than $6. In addition, engine re-builders are a likely source for a used nut suitable to make the tool Jim suggests.
 
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During this time of "stat at Home", I have been re-reading some of my Model "A" News and Restorer magazines before I start the day.

Low and behold, this morning while reading the Tech Q & A section of the Model "A" News there was a mention of the cam threads.(pg 7).

It states they are 1-16 U.S.F. Milled Thread. It also says that U.S.F. later became U.S.S. or fine threads today. This info from the Benson Ford Library.
 
Screw threads have evolved a lot over the years. Unified National Course and Fine are pretty well know but there is also a Unified National Special or UNS thread pitch specification that has stumped more than a few old prewar Harley Davidson enthusiasts. The special pitches they used were half way between UNC and UNF threads. I guess they wanted the exclusive rights to the HD hardware. Finding the taps & dies for these is difficult but not impossible. I have the most common sizes. Another odd one was the British Standard Cycle thread. No matter how big the bolt shank is, they all had 26-TPI threads.
 
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