The Forestry Forum

General Forestry => Chainsaws => Topic started by: markct on September 18, 2008, 04:27:00 PM

Title: sharpening chain, how far down to grind rakers?
Post by: markct on September 18, 2008, 04:27:00 PM
my local dealer seems to not want to grind the rakers of the chains, and naturaly it ticks me off when i pay 8 bucks and the saw chain makes dust till i hit the tops of each raker and grind off a bit then they cut great. i just been doing what looks about right, which when i measured one was about .025  and they seem to cut good that way. when i get them back from the dealer they have been as little as .005 below the tooth and just dont want to make a chip that way, they just make dust and are slow as heck.  i was just curious what is correct or if its just a trial thing, this is on an ms310 stihl saw, and does it make a difference weather its skip tooth or regular, i use both but do like the skip tooth for the fast cutting and quicker sharpening.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: WDH on September 18, 2008, 04:53:10 PM
I use a combination guage.

http://www.usa.husqvarna.com/node3287.aspx?nid=59874&pid=25524
Title: Re: sharpening chain, how far down to grind rakers?
Post by: ely on September 18, 2008, 05:06:03 PM
it depends on what i am cutting most. if i am in pine i take alot off the rakers if i am in hardwood i take a little less off.  if i use my pine chain in the oak i have to hold the saw back too much as it gets too big of a bite. with a little practice you will get the feel of it. before long you will be saving 8 bucks and just doing it all yourself. good luck
Title: Re: sharpening chain, how far down to grind rakers?
Post by: beenthere on September 18, 2008, 05:31:05 PM
Why take any chances free filing the rakers....a guage is more precise and takes the guess work out of it.

I use the one WDH linked to, and it is about $8 or $9.
That is close to what you are being charged for one filing. And it is about fool proof...at least for the fool I am... ;D ;D ;D


Title: Re: sharpening chain, how far down to grind rakers?
Post by: Rocky_J on September 18, 2008, 05:34:52 PM
25 to 30 thousanths is about right.  :)
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Kevin on September 18, 2008, 06:03:59 PM
Get the chain manufactured specs for the specific chain.
It's usually on the back of the box.
This picture isn't clear due to the down sizing but this is what the Stihl box looks like.

(https://forestryforum.com/gallery/albums/userpics/10030/stihl_chain2.jpg)
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Cut4fun on September 18, 2008, 06:57:44 PM
Quote from: Rocky_J on September 18, 2008, 05:34:52 PM
25 to 30 thousanths is about right.  :)

Thats what I use 25 hardwood, 30 softwood.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: thedeeredude on September 18, 2008, 07:18:28 PM
Check out that page on Carlton chain website called How Saw Chain Works.  They have really good info on depth gauges.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: cheyenne on September 18, 2008, 10:36:01 PM
.25 & .30 thousandenths is what's recomendend. A good gage is a must. Sharpen them yourself & find a new dealer. It's not that hard it just takes practice, go slow & do it right you'll get the hang of it. Touch them up when you gas up. We all hate it, we want to saw but it's what we have to deal with in order to have so much fun. Cheyenne
Title: Re: sharpening chain, how far down to grind rakers?
Post by: sawguy21 on September 18, 2008, 10:50:36 PM
I questioned one of our techs when he did not touch the rakers. He replied that the company did not pay him enough to spend the time on them, if they needed doing, replace the chain. ::) He was paid by the hour and was too lazy to change the wheel. I suspect some shops take the attitude that the dumb consumer will not know the difference so will not pay to have it done properly.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Rocky_J on September 18, 2008, 11:00:16 PM
Actually, the shop is more right than you know. You're at that 'in-between' stage where you're finally beginning to learn about how a chain should be sharpened but you haven't yet begun to file your own chains yet. One or two more wasted trips to the dealer to let the kid grind your chains wrong for $8 a pop and you might be ready to buy a couple files and begin filing your own chains.

95% of people who pay to have their chains sharpened don't know the difference. Those who do know, won't let the kid with the grinder near their chains. And grinding changes the temper of the teeth so the chain is more difficult to file by hand after the kid has cooked the teeth by getting them too hot.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Dan_F on September 19, 2008, 12:31:24 AM
Some people probably wont like this but I eye ball it. A set number of passes with a flat file depending on how much the teeth are filed. I also side file the rakers starting when the chains are about half wore out. I get all I can out of them and like then to grab just a bit. ;D
Title: Re: sharpening chain, how far down to grind rakers?
Post by: beenthere on September 19, 2008, 02:11:55 AM
Quote from: Dan_F on September 19, 2008, 12:31:24 AM
Some people probably wont like this but I eye ball it. A set number of passes with a flat file depending on how much the teeth are filed. I also side file the rakers starting when the chains are about half wore out. I get all I can out of them and like then to grab just a bit. ;D
Dan
Not up to us to like it or not like the way you like to do things... ;D If you like it, that is good enough for me.
Now, I expect redwood is much more forgiving that white oak, but that would just be my guess.

I don't follow the 'side file' of the rakers.  ::)
Title: Re: sharpening chain, how far down to grind rakers?
Post by: thecfarm on September 19, 2008, 07:10:20 AM
markct,we talked about sharping a chain a while ago.
https://forestryforum.com/board/index.php/topic,23764.0.html
It took me a few chains to get the hand of it.If you have any questions we will help.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: ely on September 19, 2008, 08:57:06 AM
i use a small flat file that is about 6 inches long, really fine cut. i take 3 strokes per raker for hardwood and maybe one less for soft wood.
do them all equal just like when you sharpen the chain. or your chain may start to jump up and down while cutting. never seen that but it could.
put the flat file down on  the chain from cutter top to cutter top and look at the clearance you have on a raker, before and after you file them. you can see what you are taking off.
like the guys said, they have a guage that you put over the chain and file off what sticks up, pretty simple but i never used one.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Cut4fun on September 19, 2008, 12:53:36 PM
Here are links explaining rakers, gullets, how a cutter works, and angles for ripping chain.

http://www.madsens1.com/bnc%20depth%20gauge.htm

http://www.madsens1.com/bnc%20gullet.htm

http://www.madsens1.com/bnc%20how%20wks.htm

http://www.madsens1.com/bnc%20rip.htm

http://www.madsens1.com/MNUbarchain.htm
Title: Re: sharpening chain, how far down to grind rakers?
Post by: markct on September 19, 2008, 12:56:02 PM
QuoteActually, the shop is more right than you know. You're at that 'in-between' stage where you're finally beginning to learn about how a chain should be sharpened but you haven't yet begun to file your own chains yet. One or two more wasted trips to the dealer to let the kid grind your chains wrong for $8 a pop and you might be ready to buy a couple files and begin filing your own chains.

95% of people who pay to have their chains sharpened don't know the difference. Those who do know, won't let the kid with the grinder near their chains. And grinding changes the temper of the teeth so the chain is more difficult to file by hand after the kid has cooked the teeth by getting them too hot.

dont get me wrong i file my chains myself, but when one gets damaged to the point i would spend forever with a file, especialy on these hard stihl chains, then i send them to the shop to get ground, i usualy touch up my chains every day i use them with a file, i just send them out when they are badly dinged from a rock etc. i did order a carlton chain grinder last week so it should be here any day thats why i was wanting to know a bit more exact the depth they should be
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Al_Smith on September 19, 2008, 02:18:26 PM
Eight bucks a pop,you've got to be kidding .For about 10-12 you can get a brand new from Baileys when they are on sale for a standard 72 driver 3/8" .050 .

Take that money and buy a dozen files and have at it. Better still ,buy an Oregon file guide and a dozen Perferds. Before too long you will get the hang of it I'm sure . It takes about 5 minutes to wiz around a 20 inch loop unless you rock it .

Nobody started life as a good filer,for better or worse we all had to learn at some time .
Title: Re: sharpening chain, how far down to grind rakers?
Post by: ely on September 19, 2008, 04:19:49 PM
Quote from: ely on September 19, 2008, 08:57:06 AM
i use a small flat file that is about 6 inches long, really fine cut. i take 3 strokes per raker for hardwood and maybe one less for soft wood.
do them all equal just like when you sharpen the chain. or your chain may start to jump up and down while cutting. never seen that but it could.
put the flat file down on  the chain from cutter top to cutter top and look at the clearance you have on a raker, before and after you file them. you can see what you are taking off.
like the guys said, they have a guage that you put over the chain and file off what sticks up, pretty simple but i never used one.
SORRY BOUT THAT, i got the strokes backward on that statement above, its less for hard wood. ;D
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Dan_F on September 20, 2008, 02:00:03 AM
Quote from: beenthere on September 19, 2008, 02:11:55 AM
Quote from: Dan_F on September 19, 2008, 12:31:24 AM
Some people probably wont like this but I eye ball it. A set number of passes with a flat file depending on how much the teeth are filed. I also side file the rakers starting when the chains are about half wore out. I get all I can out of them and like then to grab just a bit. ;D
Dan
Not up to us to like it or not like the way you like to do things... ;D If you like it, that is good enough for me.
Now, I expect redwood is much more forgiving that white oak, but that would just be my guess.

I don't follow the 'side file' of the rakers.  ::)

If you look down a chain you will notice that the rakers curve outwards just like the teeth. As the chain gets filed down its kerf gets ever so slowly narrower. Side fileing the rakers simply allows the teeth to cut more from the side.

We have some very dense wood out here too (Madrone, Coast live oak) and yes I tone down my fileing when I'm cutting a lot of that.
Title: Re: sharpening chain, how far down to grind rakers?
Post by: Tom_Averwater on September 28, 2008, 08:35:09 PM
Talk about a kid sharpening saw chains .My brother had his 6 year old daughter grinding chains the other day, and she did a good job of it!