angle guide for bench grinder

[mr_skittle]

I recently picked up an aftermarket tool rest for my old Delta combo grinder. The factory tool rest was a total POS that I haven't been able to get a decent grind using it. I've been using sandpaper to rehab nasty old blades instead. I got the grinder and the tool rest mounted to a board no problem and gave it a try. I'm pretty happy with how it works and I can already tell its going to save me soooo much time and hassle when it comes to establishing a new edge. I did my best to line it up for the right angle but was a bit off when I put the chisel into my veritas jig to finish up the honing. I know the veritas tool rest comes with a little tool to set the angle but I'm sure some of the folks here have come up with great homeade jigs for setting the angle of the tool rest for a grinder. Ideas? 


[attachment=2239]

[blackhat]

1/2" X 1/2" sticks with the desired angle cut on the end seem to work just fine.

[mr_skittle]

Could it really be that easy? I'm starting to think that I've been overthinking this...

[Alan S]

There are more versatile adjustable angle finders.  The stick with the angle on the end works better.

[Derek Cohen]

This is from my website:


Angle Setting Jig For Dry Grinder



Here is a jig to set the angle on a dry grinder. It can be made for any angle.

My grinder set up is an 8” half-speed machine with the Veritas tool rest. The wheel is a 46 grit Norton 3X.

Adjusting the tool rest for a specific angle needs to take into account two factors, the diameter of the wheel and the thickness of the blade.

As the diameter of the wheel becomes significantly smaller, it will be necessary to make a fresh jig (I emphasise “significantly” smaller since a little bit here-or-there is not important in the grand scheme of things). The only jig I am aware of that adjusts for different diameter wheels is the Tormek. However the is not enough room to use one on a dry grinder with wheel guards.

Each time the jig is used, it must account for the thickness of the blade. This is done by placing the blade on the tool rest, and then the jig on top of the blade.

Tighten the tool rest setting once it is set up as in the above picture.


The Jig




Making the Jig

The dimensions are not relevant and may be made any size you please. The jig in the picture will grind a 25-degree hollow.

1. Use a blade with a known bevel angle (say 25 degrees).
   
   
   
2. Set this up to grind such that it will create a hollow at the middle of the bevel. To test this, use a felt tip marker (texta, magic marker) and colour the bevel. Place the blade on the rest and – with the power off – move the wheel back-and-forth to create a slight scratch pattern. Adjust the rest until the scratch is in the centre of the thickness of the bevel.
   
   
   
3. Retract the blade on the rest until it no longer touches the wheel (you may wany to clampit here so that it does not move).
   
   
   
4. Place a block of wood on top of the blade and hollow grind that. This will give you a template to reproduce that angle.
   

1. Do another for 30 degrees (and any others you wish).
   

Regards from Perth

Derek

[pprobus]

The latest issue of Woodsmith has a pretty good design.