grinding rakers with super jolly -

Hi Guys -

I was sharpening up one of my 32" loops with the super jolly and decided to play with raker depth a little bit.

What I did was manually filed one of my rakers to the standard .025 and then put the chain on the grinder. I dropped the grinding wheel depth down to where it just kissed off on the right hand cutter raker. I then put a .005 shim under the adjustment knob and then lowered the grinding wheel until it kissed off again on the same raker.

In theory, should now be grinding a .030 depth. I did every raker left/right with the same setting. What I noticed was the left hand rakers didn't seem to have the same amount taken off, based on the little flat that was created after grinding. I went back and touched the LH rakers a little more to get them more even with the RH side.

It seem to me that I should be grinding the RH rakes separately then resetting for the LH rakers. Does that make sense? In any case, I really liked the .030 depth in oak. Wasn't grabby and was really fast. Next time around I may go another .002 and see what happens.

Just curious how other folk grind their rakers...

Joe

 

Are all the rakers centered under the same part of the wheel where it makes contact?
What would happen if you did all the lefts and then took chain off and flipped it around then did the rights??

 

'EFFIN BRILLIANT!!!

That never even occurred to me. Geez, I are so dumb!!

Thanks Buzz!!

<heads off to the woodshed to flog himself>

 

Sometimes I grind rakers on one of my grinders. But the chain vice I have slides back and forth so I can get both sides of the rakers the same.
I have also shaped the wheel to the desired shape of the raker so that I am not getting just a flat grind.

 

that would work if the grinder head was at 90°

 

I was assuming it was set at 90 since it was rakers.

 

I do mine at 15° with a profiled wheel....flat rakers chatter and cause vibration

 

Thats a good thing to keep in mind. Thinking that if I look at a new chain the raker certainly isn't flat on top.
Thanks for the tip.

 

Yup. I did the same thing originally and then figured out that Lh Rh rakers hit the wheel in different spots coming down. Nothing like getting a college education only thing is u will never forget again learning from a mistake. And sometimes it works out for the better.

 

Learning from a mistake is just part of life. It still happens even at my age.
Not always a bad thing , it does for sure teach you a lesson that you won't forget and also opens your eyes for the next bump in the road.
Thats all part of the fun.

 

Guessing the grinder isn’t perfectly calibrated. Turning the dial up from .050 to .058 or .063 will move the center of the chain in and remove less from the left side and more from the right. Moving it to .043 will take more off the left and not so much on the right. Once you get it right, you can pop the snap ring off, remove the dial, and reinstall it so it lines up with .050 and matches your chain

 

Using a .005 shim under the stop will add about .012 at the wheel.

I tried grinding rakers and quit because the teeth are not made all the same and each raker needs to be set for it's own tooth.
I have filed the rakers on brand new chains and they can be all over the place. Rarely too low, but commonly too high. I ran a new chain and then filed the rakers and it cut smoother and faster when they were even. Chain is mass produced, so it needs some work to be perfect. Most people don't care and just run it, but I like to get the most out of it.

 

I do rakers progressively, so each one is set perfectly for its cutter.
Use a progressive depth plate? Check this one out

 

Well that's interesting. Why would that be? When I ground the rakers, it looked like it was more that .030 clearance between the top of the tooth and the raker, but since I was eyeballing it, didn't think to much of it.

 

because the stop is closer to the hinge than the wheel.

 

Ideal raker depth can be different for each saw and depends on saw hp, the wood, cutter length, bar length, and elevation. I keep mine at .025-.040 because I run ported saws and have different bar lengths. I am still finding the best setting for my 350. I want enough load on the saw but I don't want it to bog down in the cut. I had them at .030 last week in elm and it was doing 12-23k, which is great. Thise are brand new cutters and they have some hook in them. Once it gets sharpened and the hook is gone, the raker height might have to change.

 

Why would you need a shim?is the stop on your grinder not adjustable?

 

yes, its adjustable. What I was trying to do is get a different raker depth than my .025 depth gage. I used a .005 shim under the stop thinking (incorrectly) that once I "re-zeroed" the grinding wheel, without the shim I would be taking an additional .005 off the raker for a total of .030.

 

You can buy different raker gauges online. Anything from 10-50 thou.

I guess the important question is why you want shorter rakers.

 

Not enough hook?