Anybody Ever Change A Tip Sprocket In A Stihl Rollomatic Bar?

[SteveSr]

It’s great to have a practice bar! Save it for filing chains.

And for mounting a saw carcass in a vice for removing the clutch and FW nut!

You can use a center punch, or a nail set (flat tip, instead of pointed). Tap it gradually. Place the bar over a block of wood with a hole drilled to accept the rivet.

Well, a drift punch (flat end) with a hammer and a drill press vice as a backer was an unfulfilling experience. Nothing budged. So I started drilling out what appeared to be the peened side of the rivet and the punch still didn't do anything. Drill some more. Finally got some movement. Turns out that the rivet was bulged into the entire bore of the center bearing.

So would a chain breaker/spinner be a better option? Arbor press? Time to hit up friends to see if I can find either.

As for the rivet dimensions:

Diameter - 4mm
Head Diameter - 6.3mm
Bar width - 0.178"

 

[SteveSr]

Went looking for standard rivets. The most popular seem to be DIN 661 (see attached). However, these don't fit the DIN 661 specs in several ways.

There are also other rivet standards listed here:

https://www.globalfastener.com/standards/detail_89.html
I took a quick look through most of these and didn't find any matches.

It looks like this may be a proprietary part to Stihl.

Begining to look like pay through the nose for the correct part or get out the file/grinder.

 

[SteveSr]

I did some more searching and found the Stihl part numbers hiding in their Bar & Chain catalog. I'll attach a 2018 copy below.

For this project it looks like I would need either of the following:

3003-650-9928 - 3/8" .050 10T sprocket kit ( $18 Bryan 2022)
0000-974-0420 - Rivet ($2.50 ea! Bryan 2022)

I checked some local prices at several Stihlers...

The bar tip kit was $24 to $35 but was back ordered by Stihl.

The rivets were $3 to $5 per rivet! and were available.

 

[Philbert]

The rivets were $3 to $5 per rivet! and were available.

I recall buying chain presets from STIHL. They were about $1.25 each, but only $.50 each, if I bought a bag of 8 to 10. Maybe same with rivets?

Philbert

 

[Philbert]

Here are some page shots from an older copy of the ‘Oregon Maintenance and Safety Manual’.

Philbert

 

[J D]

I'm interested in this.

I mill with Stihl 3003 mount bars, using picco/lo pro chains. Will a Stihl 3/8 picco bar sprocket fit Stihl 3/8 E bars?

The nose profile would need to be the same or very close. If that were the case & the internal dimensions didn't match it wouldn't be hard to make a new centre that matched one to the other

 

[SteveSr]

I recall buying chain presets from STIHL. They were about $1.25 each, but only $.50 each, if I bought a bag of 8 to 10. Maybe same with rivets?

Philbert

I would need a part number for that. I didn't see it in the B&C manual.

I also found these on Ebay claiming to be Stihl parts:

https://www.ebay.com/itm/1329965875...0dAZCckieFLdn79tNMav60Xg==|tkp:Bk9SR86dvdaRYg
https://www.ebay.com/itm/2335985861...iLt9+b0uSh0RZKmvkX0Spykg==|tkp:Bk9SR86dvdaRYg
However, these look "fishy". The heads look way too thick and the chamfer angle looks too small. If these were real it would mean that Stihl would have to surface grind down the heads on every bar, a significant manufacturing cost.

 

[SteveSr]

Here are some page shots from an older copy of the ‘Oregon Maintenance and Safety Manual’.

Philbert

View attachment 1088253
View attachment 1088252

So what is the tool used in Step 1? Is that a chain breaker or some other kind of press?

 

[SteveSr]

Stihl sells the kit. Did one about 6 months ago. Not that bad with new rivets. Usually the bar is so far gone it is not worth the cost.

When you did this replacement did you have to file/grind down the rivet heads after you set them to make them flush with the bar?

 

[Philbert]

So what is the tool used in Step 1? Is that a chain breaker or some other kind of press?

Yes.

Visit the thread posted above to see me using mine. I also pulled the assembly out on a thin piece of card stock, *** over an old towel ***, because I was planning on reusing all of the parts, including the tiny roller bearings.

https://www.arboristsite.com/threads/nose-sprocket-rescue-illustrated.256640/
Note that STIHL might have different sized rivets for different sized bars, plus different rivets for installing Replaceable Sprocket Nose (‘RSN’) bar tips.

I was surprised when my dealer told me that a lot of their PRO users don’t even bother replacing RSN tips (!!!). $24 for the part, plus 15 minutes shop labor ( at whatever rate), plus waiting a day. They just buy new bars and figure it into the cost of the job / doing business!

I can see needing a replacement bar right away, but would still buy the part and get to it on a slow day for backup: $24 versus a $60 - $80+ bar?

Philbert

 

[SteveSr]

I recall buying chain presets from STIHL. They were about $1.25 each, but only $.50 each, if I bought a bag of 8 to 10. Maybe same with rivets?

Philbert

I would need a part number for that. I didn't see it in the B&C manual.

@DND 9000 Are the stihl bar tip sprocket rivets (0000-974-0420) available in multi-pack quantities? If yes, Stihl part numbers for them?

 

[SteveSr]

Yes.

Visit the thread posted above to see me using mine. I also pulled the assembly out on a thin piece of card stock, *** over an old towel ***, because I was planning on reusing all of the parts, including the tiny roller bearings.

I saw that but didn't know what that big red cylinder thing was. Is that hydraulic chain breaker?

 

[Philbert]

I saw that but didn't know what that big red cylinder thing was. Is that hydraulic chain breaker?

It’s a very simple arbor press. I believe a cam presses down on a spring loaded arbor.

A punch / drift of the right size will work.

Philbert

 

[bwalker]

By the time a tip blows on those cheap laminated bars they are about shot in most cases.

 

[SteveSr]

By the time a tip blows on those cheap laminated bars they are about shot in most cases.

Well, in this case the bar was brand new. I suspect that bar oil hadn't penetrated the nose before I started cutting with it. Live and learn. replaced it with an Oregon RSN bar that had grease in it from the factory. Same cutting scenario... no problem.

 

[bwalker]

Well, in this case the bar was brand new. I suspect that bar oil hadn't penetrated the nose before I started cutting with it. Live and learn. replaced it with an Oregon RSN bar that had grease in it from the factory. Same cutting scenario... no problem.

If the bar is new it may be worth it to replace the sprocket.
Those roller bearings will run a long time with little oil btw. My brother ran almost a entire tank of gas through a saw with no bar oil with no apparent damage.

 

[SteveSr]

Which Side was the rivet peened? And what are the signs/clues?
Bar #1


Side A



Side B

 

[SteveSr]

Which Side was the rivet peened? And what are the signs/clues?
Bar #2


Side A



Side B

 

[SteveSr]

Which Side was the rivet peened? And what are the signs/clues?
Bar #3


Side A



Side B

 

[SteveSr]

If the bar is new it may be worth it to replace the sprocket.
Those roller bearings will run a long time with little oil btw. My brother ran almost a entire tank of gas through a saw with no bar oil with no apparent damage.

I can't explain what happened. May be interesting to see the carnage once I get it apart.