iDRY Vacuum Kilns

Sponsors:

How Important Is The Down Angle

Started by Dieselman, February 09, 2013, 09:35:35 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Dieselman

One of my chainsaws uses a 95VPX chain.  According to the chain's manufacturer, the chain should be sharpened with a 10 degree down angle, but with a note that when sharpening with a hand file to use a 0 degree down angle.  I currently use an Oregon Sure Sharp bar mounted guide for sharpening, but want to get a power sharpener which unfortunately does not have the provision to vary the down angle.

My question is how important is the down angle?  On the times I have had my chain professionally sharpened, I have not watched the personnel to see if they adjust for the 10 degree down angle or just sharpen the chain to 0 degree down angle.

Thanks.

Al_Smith

On micro chisel Oregon chain some including myself file the compound angle and some do not .I think the compound angle helps it and some think it's a waste of time .It will cut either way though for that matter .

lumberjack48

I always used the 10 degree's when hand filing, it pulls a little smaller chip. Which means more chain speed, a faster, smother cutting chain.

But like Al said hardly noticeable

Hi Dieselman, glad to have you here
Third generation logger, owner operator, 30 yrs felling experience with pole skidder. I got my neck broke back in 89, left me a quad. The wife kept the job going up to 96.

HolmenTree

Back in the day when the taller cutter sideplate chisel and semi chisel chains were introduced, a round file held level at 0 degrees puts a blunt angle on the top plate of the cutter. Where as the old style chipper chain wasn't affected so much.
By lowering the file handle 10 degrees the inside corner of the top plate is thinned out with less bluntness, plus less angle or "hook" is applied to the sideplate of the cutter.
Oregon sawchain recommends 10 down on most of their chain, Stihl just keeps it at level 0. At one time not that long ago Stihl recommended 10 down.
Making a living with a saw since age 16.

beenthere

Thanks for that explanation, HolmenTree.

I do the 10°, and wondered why Stihl was now onto the zero recommendation.
south central Wisconsin
It may be that my sole purpose in life is simply to serve as a warning to others

HolmenTree

Quote from: beenthere on February 09, 2013, 06:37:16 PM
I do the 10°, and wondered why Stihl was now onto the zero recommendation.
I wondered that too. My 066 owners manual from the early '90s says 10 down, but sometime after that they changed their minds.
The way I see it the Stihl sawchain is heavier built then the Oregon chain, so the Stihl chain should take more abuse from the blunter top plate with the 0 degree filing angle.
Things are keep simple, and the fact that there are alot fewer pro endusers today then there was 20 years ago, advanced filing angles are not so critical in todays times. 
Making a living with a saw since age 16.

Dieselman

Thanks, guys.  I'll go back and re-sharpen this particular chain with a 10 degree down angle.  I'm in Atlanta, GA so frozen wood is not a problem here.  I was cutting up a tree which had a trunk diameter larger than my bar (22" trunk, 18" bar), so it was pretty much a worst case scenario for the saw. I had to go really slow so I wouldn't bog the saw down.

Al_Smith

A few years back I bought a few loops of Baileys house brand ,Arbor Pro or whatever it's called .Did fine until I refiled it which I had compound angled it .Oh terrible .Filed ,refiled filed again . Got mad about it and hung that loop on a nail .

It was only several months later that good ole "Crofter " AKA Frank W. from Ont. showed me the error of my ways .Evidently that stuff is Carlton chain and it doesn't do real well with a compound angle .

So I layed the file to it again using a straight 90 degrees on the top plate and it cut fine plus I learned something .I still don't know why it didn't work but evidently the way I did it must have screwed up the "working corner " where the top plate and side plate intersect .

HolmenTree

If you all could bear with me, I'll try and explain better about the 10 degree down angle method I talked about earlier.
This angle method was adapted when the semi chisel and chisel chains were developed in the late 1960s and early '70s. These chains had a taller, flatter side plate that needed a new filing angle versus the level method used on the standard round or chipper chain.

If the file handle was lowered 10 degrees on the chipper chain which has a shorter [lower] side plate a negative cutting angle in the sideplate would result, even going into a backslope resulting in a very poor cutting chain.
Now with the semi chisel and chisel cutter sideplate having increased height and flatness the filing method used on the chipper chain would produce a severe hook on the chisel chains.
The level held file could be raised to produce a proper side plate cutting angle, but the top plate cutting angle would turn out too blunt.
So how do you fix this? You guessed it........drop the file handle 10 degrees. This action raises the part of the file that contacts the sideplate and lowers the file section that shapes the top plate cutting angle.....now both angles are perfect.
Making a living with a saw since age 16.

CX3

I file my chisel chains at 0 level. They cut fine. I have tried 10° with no better results
John 3:16
You Better Believe It!

Al_Smith

Oh it's probabley just academic .I for one like to see the saw where you just "drop the reins " in a mannar of speaking ,give it the gas and let it cut as it will .Pulling big chips and running like a maniac rather than having to lean hard  on it ,dog down the engine and work the saw as well as yourself into a melt down .

I soup the things up if and when I feel like it .I'll be the first one to admit though that 10 minutes of good file work will get you just about as much as a tricked out engine with a lousey chain .Maybe even more .

HolmenTree

Quote from: CX3 on February 10, 2013, 10:41:55 AM
I file my chisel chains at 0 level. They cut fine. I have tried 10° with no better results
Time them with a stop watch and you'll see. :)
That's my first advice for you......... how to win at chainsaw races ;)
Making a living with a saw since age 16.

Al_Smith

You can hook them a little bit but it robs some power plus you'll dull the chain quicker .

I got to thinking about this and that Carlton chain and never took the time to look today .I kind of think it was 35 degrees top angle instead of 30 .Now if so it probabley means the compound angle needs to be something different than 10 degrees .At the time it annoyed me so much  I never persued it any further .Come to think about I might even have a new loop some place .Just where it might be hiding I haven't a clue .

HolmenTree

Quote from: beenthere on February 09, 2013, 06:37:16 PM
I do the 10°, and wondered why Stihl was now onto the zero recommendation.
Ok, after a little more brain storming today I can now say why Stihl specs  the 0° angle and why Oregon recommends 10° down on the file handle.
  Like I explained in my last few posts I do understand the history of how the 10° angle evolved. Most of my working life I have filed sawchain "free hand".

I have 3 different sawchain boxes in front of me, the Woodland Pro 30RC [rebadged Carlton A1] shows "side plate angle" 80° [10°down]. The Stihl box shows 90°on all their chains. The Oregon box shows 10°down on all but 3 of their chains.
Now after reading the small print on the Oregon box it says "*When using an Oregon Filing Guide, ALWAYS hold it level, 0°, flat on the top plate".
Then looking at the Stihl box specs, it shows a file and file guide [Stihl calls it a "file holder"] in the cutter with their 90° setting printed in black and white.

So there you go it makes sense a file with file holder or file guide attached is not designed to be used with the file handle down 10°. It can't work with the file handle 10° down because the guide rests and glides on top of the cutter and depth gauge, it has to be held level to make the proper angles. Stihl has for years promoted their file holder.
Making a living with a saw since age 16.

HolmenTree

Quote from: Dieselman on February 09, 2013, 09:35:35 AM
One of my chainsaws uses a 95VPX chain.  According to the chain's manufacturer, the chain should be sharpened with a 10 degree down angle, but with a note that when sharpening with a hand file to use a 0 degree down angle
I think what you meant was file guide not hand file.......... Read my last post.
Making a living with a saw since age 16.

HolmenTree

Quote from: Dieselman on February 09, 2013, 09:35:35 AM
  I currently use an Oregon Sure Sharp bar mounted guide for sharpening, but want to get a power sharpener which unfortunately does not have the provision to vary the down angle.

I have had my chain professionally sharpened, I have not watched the personnel to see if they adjust for the 10 degree down angle or just sharpen the chain to 0 degree down angle.
Yes bench mounted chain grinders can be set for 10° down angle, it's called "offset grinding".
To accomplish this the cutter must be moved further away from the grinder stone's verticle centerline. Two different methods are used by chain grinder manufacturers to do this:
First method moves the chain vise away from the stone's verticle center. The other method tips the cutter away from the stone by means of a tilting base for the chain vise. Each method produces the same results and, therefore, one method has no advantage over the other.
Making a living with a saw since age 16.

Al_Smith

Aha,the rest of the story .It never dawned on me about the misalignment of using a file guide with a compound angle which in my failed attempt is probabley exactly why the failure .

I have used an Oregon file guide for years to periodically realign things which although the free hand method is normally pretty accurate can drift off at times .

Now using a guide on a compound angle would in fact misalign the working corner and in effect actually cause a blunt corner by moving it more towards the outer side of the top plate instead of the junction point of the top and side plates .Good info .

HolmenTree

 

  

 
Quote from: Al_Smith on February 11, 2013, 06:18:55 AM
Aha,the rest of the story .It never dawned on me about the misalignment of using a file guide with a compound angle which in my failed attempt is probabley exactly why the failure .

I have used an Oregon file guide for years to periodically realign things which although the free hand method is normally pretty accurate can drift off at times .

Now using a guide on a compound angle would in fact misalign the working corner and in effect actually cause a blunt corner by moving it more towards the outer side of the top plate instead of the junction point of the top and side plates .Good info .
Thanks Al. but we're not quite finished yet :D
This is really going to confuse you as I am totaly not sure what goes on here. Here is a page from my 1992 Stihl 066 owner manual with the Stihl file holder being used on the 10°down and also info about "frost in the wood". The other full page is from my 1986 Stihl 064 manual , no mention of "frost" but shows good detail into the 10°angle with the file holder.
Now my question is, is the Stihl file holder designed different from the Oregon model to allow for this 10° down angle? I have an old Oregon file guide kicking around that I used when I first learn to file when I was a teenager, but I don't have a Stihl model to compare.
Making a living with a saw since age 16.

Al_Smith

Well that's a good question but unfortunately like yourself I have  no Stihl file guide to reference it to.Oregon I have as well as a picture some place of it in use . Ah found it >

 



I took this pic a few years back as a kind of a tutorial for a young lady on another site .That's Oregon chain with about a 10 down so it must have worked on that brand .Kind of tough to hold a file with one hand and focus a camera with another .

lumberjack48

I could never use a guide because i couldn't see what my file is doing. Its like your guising what the file is doing, i want to see every stroke of the file and watch the edge come back on the cutter. Sometimes it might only take one stroke of the file to put the edge back on.
Third generation logger, owner operator, 30 yrs felling experience with pole skidder. I got my neck broke back in 89, left me a quad. The wife kept the job going up to 96.

HolmenTree

Quote from: lumberjack48 on February 11, 2013, 02:39:15 PM
I could never use a guide because i couldn't see what my file is doing. Its like your guising what the file is doing, i want to see every stroke of the file and watch the edge come back on the cutter. Sometimes it might only take one stroke of the file to put the edge back on.
I'm with you on that lumberjack, but when I was just a young greenhorn my foreman handed me a Oregon file guide like the one in Al's picture. I learned the basics with it , even put tooth picks between the file and guide to get more hook in my chain, but it sure didn't take me long to leave it in the shop.

I was in at the local True Value hardware store today and found one of these Oregon 7/32 file guides hanging on the wall, the salesmen said it's been there for about 5 yrs. I look on the back of the package and low and behold, it had 10° down on the handle in the specs. Now what these new chain boxes with 0° spec has me confused. ???
Making a living with a saw since age 16.

Al_Smith

I don't think those guides have raised more in price than maybe  a dollar in 20 -25 years except they aren't made as well as the old ones. Those  used a j-bolt type of thing to hold the file in place instead of the spring steel clips they use today.

The things will hold the file about the right distance up into the top plate and you have the angle on the top to guide to .Most chain any more have the angle witness marks but back when these things came out they didn't .We're talking chipper chain days here .I never even saw chisel chain until the late 70's early 80's .

I run the gullets deep clear to the tie straps which you can't do with a guide .I don't know if it cuts any better that way or not but they hold a big chip.

lumberjack48

The Ole chipper chain, now weren't those the days Al. Saw chain was expensive back then, i'd run-em on till there were no cutters left. I sliced my finger many times on a chipper chain when the file would slip or jump out of the cutter.

I can see myself out in a Spruce Swamp[1965] strip cutting with a broken chain. I had real good tools to fix it, i used a flat file, 1/2 inch drive socket, i can't remember what size, a hammer and a nail. It wouldn't take me long, i'd be cutting again.
Third generation logger, owner operator, 30 yrs felling experience with pole skidder. I got my neck broke back in 89, left me a quad. The wife kept the job going up to 96.

Al_Smith

Well we ,my family and I really didn't know any better .We weren't what you would call loggers and we just bought whatever chain they sold at the time .After I discovered chisel chain I never looked back .

It wasn't that bad really until they started selling semi chisel with anti kick backs on them that didn't cut worth a hoot .The humped type weren't that bad  but those ones with a big long link that covered the length between  cutters were terrible .

Thank You Sponsors!