Ring fab

[countryhog]

got to file couple sers of rings down and have question. In the case where ring locator pins are present is there much difference in square filing the ends vs shaping the ends to fit around the pin?

 

[jacob j.]

What are the OEM rings normally? Internally, top, or bottom notch?

Depending on the OEM configuration, you need to shape your ring ends the same way. That way you can get the ring end gap correct.

 

[countryhog]

The pin is at the top of the ring groove. See pic. Ive been told before that you could use the square end cut without loosing much compression. Tried that but doesnt work for me

 

[Basher]

View attachment 135020 The pin is at the top of the ring groove. See pic. Ive been told before that you could use the square end cut without loosing much compression. Tried that but doesnt work for me

Jer, you will always loose compression the wider the ring end gap gets, a square ring end up against a keeper pin will give a very wide ring end gap where compression will escape. Shape the ring ends to fit correctly.

 

[67L36Driver]

That would result in a .065” (ish) gap. And, a one ring piston to boot. [emoji13]

Use a 1/16” dia Swiss pattern file slowly and carefully lest you break it.

BTDT

 

[countryhog]

Where would one acquire swiss pattern files?

 

[67L36Driver]

Father-in-law’s estate.

The tiny tapered one is what I use. Out on the very tip. Very short strokes.

 

[Frank H]

Where would one acquire swiss pattern files?

Grainger, MSC, McMaster, Harbor Freight (maybe), Amazon ( I looked). Like all files, don't buy the cheap ones.

 

[countryhog]

Thanks. Dont know squat bout these files. What are good brands?

 

[RYNOSAWR]

Old Nicholson, Pferd USA.....


just don't buy chinese crap needle files..... I bought some Pferd and some other swiss pattern needle files that were made in Finland and they will cut hardened steel very well.... the chinese crap ones just rub on hard metals.... and they won't cut

You might check with some of your local gunsmiths to see if they might have some high quality spare needle files they would sell if you are wanting one quickly

 

[Basher]

Father-in-law’s estate.

The tiny tapered one is what I use. Out on the very tip. Very short strokes.

A plus 1 on the Nicholson set, mine is 40 years old and hardly shows a sign of wear, kept carded and lightly oiled over the years. Dozens of Nicholson files in all shapes still being used, some bought in the 60`s.

 

[countryhog]

Father-in-law’s estate.

The tiny tapered one is what I use. Out on the very tip. Very short strokes.

Do you know what cut number that is?

 

[Chainsaw Jim]

Round files for micro chain work very well.
Be careful to not use too large of an oversized ring. If the ring is too strong it can increase parasitic loss.

 

[smokey7]

Right or wrong ive used 50mm rings in a 48mm bore after trimming them to fit. I have also put 1.5mm rings on the surface grindee and made them 1.2mm rings.

 

[Basher]

Rings 2mm over bore size will work well when undersized but that would be my limit. Have done this for many older vintage chainsaws that no current ring will fit like old Pioneers.

 

[Basher]

Do you know what cut number that is?

My set has 4 cut on the box, the set number is 37404 and are about 5.5 inches long.

Just checked out eBay for a vintage set, the price has gotten real high for these files, Grobet also makes a set much like the Nicholson ones.

 

[huskihl]

A cutoff wheel in a dremel has worked well for me. Easy to re-shape the round area for the locating pin too

 

[Al Smith]

On this subject it might be of interest to some of how to make a ring .You won't find it on chainsaw sites but British MC and model builders do it all the time .I have 6 I never finished when I sleeved a Mac 125 engine because I found a set .
It's not that complicated but it is time consuming and tedious with many steps involved in the process . You can Google it if you want