Stihl MS250 sprocket, bar, and chain maintinance

[MrJoe]

Hi,

After trying to use McCullough and Poulan over the years, I finally took a hint and bought a Stihl MS250.
I have used to clean up after two couple of hurricanes. I had the Stihl green chain sharpend for the second time but it does not cut well and the cut curves badly to the left.
The teeth on one side are sharp and the other side dull, and I can see that more material was taken off on one side. There is still plenty af material left before the wear marks.
The 16" Rollomatic E bar seems to be flat but one of the channel walls on the bottom side has worn visible thinner than the other side and the paint is worn off on the left side.
The chain fit (right-left) is very sloppy on the bottom side of the bar, not as bad on the top side.
I did not know to flip the bar and I did not try to keep the chain sharp often enough. It did get plenty iof lube.

I am ready to buy a new bar and two yellow chains and maintain these properly.
I have read that the bar should be flipped over occasionally and the chains should be dressed frequently and alternated.
I have an Oregon rim and drum. Should the rim drive be flipped over occasionaly or always used with the "Oregon" name side up?

What intervals would you recommend flipping the bar, alternating the chains, dressing the teeth, and flipping the drive rim?

My normal annual usage is light spring time trimming and one or two 12" trees for firewood, but, I need to be ready for the next @%$!#$% hurricane.

About the old bar and chain,
I am thinking if I can get the old chain sharpened properly that I can us it with the old bar flipped over for dirty work. The bar has no use on one side because I never flipped it over.
Or, buy a cheap new chain to use with the old bar. Or, does it sound like the bar and chain are not worth trying to salvage? Recommendation?

Thanks,
Joe

 

[ballisticdoughnut]

Generally when you swap a chain flip the bar. You can do it more often if you want. Rim sprockets don’t need to be flipped they’ll wear the same regardless. As far as cutting crooked, that could be a few things. Worn out groove, inconsistent raker height, bent bar.

 

[sonny580]

When the bar wears thin on one side, ---- its history! I have rolled them in a pinch and got a little more use from them but not much and they dont cut right either, so for dirty use it could do a bit for you.
roll the bar and put the thickest side down and sharpen the chain on a grinder so both sides are even. chain will never cut right but for dirty work it will do.
Also file chain every time you gas up will help BUT after 4 tanks or so grind the chain cause nobody can file as accurate as a grinder!

 

[MrJoe]

Thanks for the experienced reply.
What do you mean by roll the bar? Flip it over?
Can you recommend an economical grinder, or type of grinder, that would do a decent job for an occasional user.
I see things from bench mounted to bar clamp on.
Based on grinding after every 4 tanks, I'm probably looking at grinding 4 time a year.

Thanks, Joe

 

[sonny580]

I use a Bel-saw bar roller, bought it back in the early 70's.It has 2 rollers, 1 solid mount and 1 sliding mount with set handle to adjust the amount of squeeze and keep it even all along the bar. Simple tool but I use it often to keep rails squeezed in to keep chain snug in the groove and extend the chain life. They also have test spacers to check the groove width but I never got any and just use the chain as a guide on mine.
After you roll the bar, see which side has the most even thickness rails and put that side down. Some guys flip the bar every time they gas up so both sides wear even and its probably a good idea to do so since that would help keep the chain straight while cutting.
I will get a pic of the roller and post it as soon as I get a chance!

 

[MrJoe]

Just in time!. I was about to find some material the corret size to put in the groove and pinch it in the vise.
I see a couple of the rollers for sale.

Thanks!

Joe

 

[sonny580]

There are some on e-bay and forest supply companies. Also you need to dress the top of the bar so its flat on both rails since 1 side wears down before the other.
HF, Northern Tool, etc. has cheaper chain grinders that will do for casual use. I have 1 set up for quick touch ups on the truck powered from a small generator to use out in the boonies and at home I have the Oregon pro model to do the serious grinding.
For the bars I grind them on a belsaw 1055 sharp-all grinder.

 

[MrJoe]

After close inspection I see what you mean about one side of the rail wearing more than the other. I have dressed it with a file and whet stone and have plenty of depth left. Maybe I will get more use out of it than I thought. I picked up a new bar so I will make some comparisons as to the the groove thickness and new chain fit. I'll get a file holder and probably one of the $30 hand held grinders to start. Thanks for the tips.

 

[MrJoe]

After close inspection I see what you mean about one side of the rail wearing more than the other. I have dressed it with a file and whet stone and have plenty of depth left. Maybe I will get more use out of it than I thought. I picked up a new bar so I will make some comparisons as to the the groove thickness and new chain fit. I'll get a file holder and probably one of the $30 hand held grinders to start. Thanks for the tips.

I just compared the old and new chains and bars. I'm glad I did so I know by feel how the chain is supposed to fit in the groove. Using the feeler guage to close the old bar did not work very well. Still too loose.
I guess the drive links in the old chain are bent (I can't see it) because it seems to push over to one side more than the other even in the new chain. It is very pronounce in the old chain where they both wore together. Maybe I should toss the old chain. I ordered two stihl chains for the new bar and two cheaper Rotary for the old bar.
I wanted semi chisel chains without the saftey bumper and am surprised how hard they are to find for the MS250. The Stihl Dealer said the 26RM62 is no longer in the catalog and non of the 5 dealers I checked had it. Just the 26RM362 (green semi) and the 26RS62 (yellow full). I ordered the 26RM62 (yellow semi) off Ebay I was also going to get a couple of Oregon chains but it looks like the same chioces. The Carlton and Rotary semi chisel non saftey that I see look like old stock.

 

[sonny580]

Most of the stuff that works is banned from manufacture by our great govt asses to keep us safe from ourselves so we are now stuck with stuff that dont work!
I had to do a LOT of grinding on a couple so called "safety chains" to make them actually cut anything! Since its only me that will ever use these chains. I never loan or let anybody else around any of my equipment anymore, so what I do with or to it wont harm anybody else.

On your top rails, you need them perfectly square and can use a tri-square or a small framing square to check them.
I have the sharp-all 1055 grinder set at perfect 90* angle and a few light passes keeps the rails even if you do it often.
Worn chain in new bar is a no-no! Also not good on a new sprocket, so keep the old set together.
If you put a new chain on an old sprocket, it will shorten the life of the new chain too, cause it dont match the drive teeth!