chain gauge

[heviarti]

I had been having terrible troubles with my 6-10 with 24 and 28 inch bars (NOS) The saw would cut for about three minutes, and then the chain would start smoking... and no, not in the wood. the saw would barely spin the chain at full throttle. I got to looking, and decided that sthe stihl I jacked my chain from had beaten the tips of the drivers with that silly rollomatic sprocket tip bar. I went and looked it over with the dial calipers, and sure as could be the drivers were .058 give or take at the bottoms, and the new bar's groove is about .054 . So, i filed all the drivers to .051-.049

I was just curious if they were supposed to be more like .048? I rather need my saw to work... Now if i could just figure out what my super 44's problem is..

 

[Grande Dog]

You should take a look at the drive sprocket. There was a point in time around the age of that 6-10 that Mac was putting out a .354 pitch. Could be the sprocket damaging your chain.

Grande Dog
Master Mechanic
Discount Arborist Equipment and Tree Care Supplies

 

[heviarti]

these are two used chains, and I assure you, all the other chains from the same saws show the same damage. the chains and bars off both my 10-10s work flawlessy. the chain is binding in the bar, because when it heats it's actually growing wider than the bar groove by enough it will stop the chain. like i said, it runs fine cold, and i've looked it over with the dial calipers. i just need to be sure of what the actual dtiver width is supposed to be for .050. i'd hate to have to turn my chain inside out again ,but i'm tired of catching schist over my macs. plus i need someting bigger than my 10-10s

 

[heviarti]

actually i wish i could just buy a new chain, but i'm too broke.. that's why i'm filing the drivers back to spec..

 

[Al Smith]

Hey Buck,old buddy,you have a .050 bar,that you are trying to feed a .058 chain through it.Won't fit.I just measured a few chains[micrometer] .050,is about .0495,.058,is about .0577.You must have the bar out to limit of it's adjustment,because Stihl,has about 2 or so more drivers per bar length than McCulloch..058 would also be an odd ball,for Stihl,more like older Husqvarna,but any thing is possible.I do,in fact,have an original 24"hard nose "bar on my 6-10,that takes 81 drivers of .058 by 3/8".The 24" GB bar on my Stihl 048-042,takes 84 drivers of .050 by 3/8".

 

[ray benson]

Used a micrometer to measure chain driver gauge.
73 LG is .058 ------------- measured .058
72 LG is .050 --- the old worn out chain measured .047
Homelite (NOS) .404 .063 ----------measured .063
Homelite(NOS) 3/8 .050 ---------measured .050

 

[heviarti]

Al, trust me on this, there is a raised spot on the driver you can hook your fingernail on.

.\XXXXXXXXX./
.. \___XXXXXX/
..........)====/

where those = marks are the driver is battered wider
yes, i had to pull a few links out for the 24, but the chain was about right for the 28.

since the rest of the body ofthe driver measures .051-.050, and the battered spot measures .058-.056.... well, you do the math.

has anyone ever mentioned this board is highly ascii-art unfriendly?

 

[Grande Dog]

If the drive link damage is getting repeated, it's usually in this order. Most likely the drive sprocket, next the bar tip sprocket, next the bar groove depth.

Grande Dog
Master Mechanic
Discount Arborist Equipment and Tree Care Supplies

 

[Al Smith]

Now I see what you mean .I took my measurements,with a cheap set of General mics,my Starretts are at the shop.3 ten thou under,would not make much difference.

 

[ray benson]

These are off the oregon site. Take a close look at your sprocket.
http://www.oregonchain.com/tech/ms_manual/ms_09.pdf

http://www.oregonchain.com/tech/ms_manual/ms_07.pdf


Ray

 

[Lawn Masters]

If the drive links were precisely .050"thick, and the rar rails were precisely .050" wide, the chain would be a little tight and not move too well. if the bar rails were precisely .050 and the drive links are .0495, the chain will have a the room to move freely, without binding, and little friction.

At least this is how I figure it.

 

[Crofter]

Measure the groove depth and compare to length of drive tangs as Grande dog suggests.

 

[heviarti]

well, i don't have an hour on either of these chains. i have maybe ten minutes on the 28. they were in this condition when i put them on the new bars. when they heat, they expand and stop the chain if this reoccurs after filing, then I have a problem, but since all the other chains off all the other stihls show the same wear pattern.... i'm pretty sure it's not me.

After several minutes of operation you literally can't force the chain around the bar with a screwdriver... and it's the bar that heats, not the drive sprocket

but judging by al and ray, my drivers should be fine where i have set them. my 10-10 is coming up on needing a sprocket and chain, but i do not forsee myself being able to do that any time soon.

The fellow I work for can be kind of obtuse at times. He complains my bigger saw isn't finished, but won't pay enough to where i can get the two welds i need made done so i can finish the saw. he makes fun of the 6-10 every day, and i keep telling him if i hadn't have had to scavenge the chains, it would work fine. and now the 10-10 is the latest topic of conversation because the chain and sprocket are so wore out it barely cuts straight. never mind i do almost all the work with the little 10-10, even making more cuts than his 064 stihl on the last job. But do you think i'm going to get a chain any time soon? I seriously doubt it.

 

[glens]

The "silly" Rollomatic bars, if they haven't been totally abused, are the best available, unless maybe you've got Canadian-made re-badged Oregons.

Think about it logically.  The only things that can possibly beat the drivers like that are sprockets, or oil dams in bars which have them and have the rails worn too much at the location of the dams (right at the oil hole in the bar tail).  If the chains came off your Stihls in that condition (and they weren't already like that when put on the saws) then you've got parts in service that have been abused or are just plain worn out and/or in need of service/replacement.

It sounds like you need to stay home to not make your money instead of wearing out yourself and your equipment doing it.

Glen

 

[heviarti]

well, i'm sure the rollomatics on matt's stihls are pretty well worn. I attribute the drivers being hammered to the tip sprocket because of the 1/8 inch dip just behind it. and the stihls.. they're not mine. i don't own any saw that isn't yellow, and i intend to keep it that way as long as i can keep one working.

He has so many chains sitting around that he's hit a nail with and blown a tooth, i just grabbed two and shortened them by pulling the broken teeth.


personally i rather like my roller nose bar,
i'd just stay home, but then i wouldn't be broke anymore, i'd be worse off.

by sundown i was half way through the second chain. I should finish the other tomorrow and be able to run them.

 

[heviarti]

ran the 28 today, worked like a charm. I just need to turn my oiler up a little.

 

[ozflea]

Check the pitch and gauge of the chain and bar sounds like the chain gauge is a little too thick for the bar groove and from memory the old 6-10's where 354 pitch, close but not close enough, the 6-10 should take the 10-10 sprocket easily enough and it's 3/8" pitch. Then you can use the chain off the Stihl if its 050 or 058 gauge Mac's never used 063 that i can recall.

 

[Al Smith]

Chain

Hey Buck ,I was going through my stuff today,and came accross an 81 driver loop of Stihl full chisel ,skip 3/8 .050.I also found some brand new,McCulloch semi chisel 3/8 .050 60 driver loops.If you give me the driver count,I can break the chain,and spin you the proper loop.I don't use skip on that short of a loop,and I don't normaly use semi chisel,so you can have them ,if you want.Free,I'll even ship them to you Happy Birthday.

 

[heviarti]

I'll pull one or all my bars off tonight and count them up, but the worst in need is my 16 inch 10-10. If breaking them is too much trouble, i do have a vise grip style break. that's how i scavenge chain. I have to go and get a new sprocket for the 10-10 soon..

Has anyone tried Total products? I am looking at their clutch drums, sprockets and bars. They are seemingly the only people that still have welded tip bars.. I keep trying to find a big roller-nose cannon for my bigger macs, but i wouldn't mind one for the ten series stuff.. that hard nose 28 does pull a bit hard.

Al, are you looking at that microfilm scanner yet?

 

[Al Smith]

16" bar

Unless it's another bar,modified to fit,a 16" McCulloch bar,for a 10-10 ,is 60 drive links.The scanner would be nice but I already have a reader,and am looking towards a Mac dealers manual .With the manual,I can just scan the info into the computer then send it as needed.