Measure Hook Angle

[HarleyT]

Well, what markings on this "gauge" are being used?

 

[HarleyT]

Normally this should be remotely obvious.

 

[HarleyT]

I mean, this chain is a mess. And it is not apparent what this gauge is measuring.

View attachment 674331

Just give me any reference point.

 

[WolfMann]

Check it out Harley, he's measuring the top plate cutting angle.

 

[WolfMann]

Same diagram, just to get on same page with everyone, I want to measure the top plate cutting angle (what I've been calling hook angle) after filing. I understand you can change it by raising or lowering file, or by using a larger or smaller file. Just not sure how best to measure it.

 

[WolfMann]

Like Harley was saying, the protractor used in the picture doesn't look like the most accurate tool for the job, although it may give a rough idea.

 

[HarleyT]

Top plate angle is looking down from the top.

 

[HarleyT]

That is controlled by the angle you run the file in respect to the direction of the chain.

 

[HarleyT]

Side plate angle would be controlled by the file diameter, ar the stone angle of a grinder.

 

[HarleyT]

Tilt is another bunch of variables.

 

[WolfMann]

I think we're calling the same thing different things.

 

[WolfMann]

I'm not talking about top plate filing angle. I'm talking about top plate cutting angle. It's in that diagram I just posted.

 

[WolfMann]

And yeah I get that file size and height will change it, I just want to know how to measure it in degrees after filing.

 

[WolfMann]

You smell what I'm stepping in?

 

[HarleyT]

Yeah, we are all likely on the same page, just using differing terminology.
I still don't see what the gauge in the pic is trying to measure....

 

[Mad Professor]

Well, just asked a simple question......

If you are trying to control the "hook" angle without a grinder, then you would look at file diameter!!!!

Simple answer, hook can be too much or too little. I've hand filed for years and somewhere along the years I got good. You put pressure up or down as you file the cutter, to make hook correct. Got that? When cutters are old/spent the file might hit the chain links. I use chains until 1 or 2 cutters break off, and those chains still cut great. Then they are stumpers.

 

[Huskitoter]

Got a compound miter saw or radial arm saw? Probably be more accurate than the protractor. Or am I off base on what you are trying to measure?

 

[WolfMann]

Trying to measure this angle after filing saw. I want it at 45° for a special ripping chain. Wondering if there's a tool for this.

 

[Philbert]

Ran across this illustration today: SO many different angles that you can describe. That bevel angle even has different names, depending on which side of the cutter you are on!

It is a straight line defining a curved edge (round filed/ground chain). I still have no way to measure it accurately without fancy machinists' tools, but it appears that the reference plane is the bottom of the cutter. I suppose that you could use the bottom of the rivets if the cutter heel or toe is excessively worn.

But again, 'hook' to me also defines how deep (rearward) this goes into the cutter, not just the angle. More 'hook' usually defines a 'self-feeding' chain: the top plate edge digs in deeper before the side plate edge has a chance to sever the wood fibers when crosscutting. Not an expert on milling chain.

Philbert

 

[Marshy]

Back to my first question, what exactly is the guy trying to measure with the "gauge" in the first pic?

I swear, some times you are a blabbering idiot. Read the title of the thread. The OP wants to measure the hook angle (also known as side plate angle. The instrument you see in the pictures is a machinist protractor.