Making a depth gauge/raker grinding fixture

There is no "perfect angle" ........... it varies by wood type, what saw is used to cut, how hard you want the chain to bite, and how long you want the cutter to last

Asking for a sharp fast cutting chain usually means the cutter needs to be sharpened sooner
Asking for a durable cutting chain usually means the chain isnt as fast cutting as it could be

There are trade offs that have to be considered for the angles you are looking for

 

That makes perfect sense. I'm just a wood cutter for heat but do cut more than most. I like a fast cut but don't need a race chain that only lasts a few cuts. I may still play around with an old chain just for grins though if I get bored.

Just as a ball park guess. 40 degrees on the top and 10 degrees on the back cut?

 

Top plate of 20 deg on a square cutter is a good start.

Here is an aggressive squared .404

Getting the inside top corner to the inside lower corner leaves a pretty sharp and durable cutter, and is a great starting point. You can play with any and all the different angles from there

 

Square Ground Chisel Angles

Square Chisel Chain Q & A

The answer about how long it stays sharp will vary with the angles you choose.

 

Here's Oregons angles for reference.

 

Thanks guys. That is the info I needed to get some ideas. Surprises me that the raker is set at only .025. I guess the this style of sharpening requires more HP to run.

 

Actually, most saws speed up with a good square cutter.
The cutter is more efficient at severing the wood fibers, so it takes less power
Another mistake that is made is in thinking that the height for round rakers equates to the height for a square cutters rakers.

 

Got around to doing all my spare chains (15) today and was asked to show before and afters on a used up chain. This is an 043 Picco going on a 192 rear handle with a 14 in bar. Chain was sharpened and the rakers had been flat ground by hand prior to grinding and were a little varied but had at least .020 depth. most were .025. Sawed first and it did okay but chattered some.




Before



After



Before



After



Before



After



Before



After

When it was done Test running the saw yielded hardly no bounce and chips were nice and consistant. Even with a pretty used up chain it was cutting like new again. One thing With this chain the finish number was .018 deeper than a 2 time sharpened chain.

I also have noticed how varied the factory stampings are. That really surprised me. When I say that I mean how sometimes the wheel will only take stock off one side of the 2 halves. It's straight but it made me wonder. Some chain runs seem to be a little different so maybe its a die wear thing or different supplier.

 

I have a Timberline grinder also. But I took the widest wheel and dressed it to the shape of the rakers and set the head straight up to zero and use it for my dedicated raker grinder. It leaves a very good shape to the raker and is very consistent from raker to raker.

Kevin that is some very nice work and some very nice equipment. Thanks for sharing that it is very impressive.
For square grinders you can google Simington grinders he used to have a web site that showed his square grinders and how they were set up. It might give you an idea on how to build your own or modify something already existing.