Secondry Bevel Edge?

[Chems]

I see a lot of references to grinding a secondary bevel on your plane irons. Yet the Tormek manual says not to do this. I'm willing to experiment thou.

Recommend me some Primary and Secondary Bevels.
I have Record:

No5 1/2 - Currently at 25 Degrees
No 60 1/2 - Currently at 22.5 Degrees
No 4 - Currently at 25 Degrees
No 073 Shoulder Plane - 25 Degrees

Thanks in Advance!

 

[woodbloke]

The Tormek should be used to grind a primary bevel only, in most cases about 25deg, secondary honed bevels are then created using a variety of stones and/or a honing guide. The reverse side of plane blades can be honed using the 'ruler trick'...but never on chisels - Rob

 

[Chems]

What about using the leather wheel rob?

 

[Derek Cohen (Perth Oz)]

It is interesting that the Tormek manual says this. I wasn't aware but am not surprised. The Tormek is for creating a primary bevel. They intend that a secondary bevel is formed when/if you use the power strop. I argue that this is an ill-advised method of sharpening.

I have a love-hate relationship with secondary bevels. They are necessary for BU planes, but create more problems than they are worth if you freehand your blades and aim for microbevels.

This is really aimed at advanced sharpeners who are beyond the stage where they are still concerned whether their edge is sharp or not.

I recently wrote an article for the FWW blog, "A Sharpening Strategy: beyond a sharp edge". http://finewoodworking.taunton.com/item/8521/a-sharpening-strategy-beyond-a-sharp-edge

I'd be interested in your thoughts. (I know it will cause a reaction with some).

Regards from Perth

Derek

 

[gidon]

Chems you can use the Tormek for complete sharpening - that's what it's designed for! A lot of people including myself use it mainly for primary bevels and then hone using another system but you don't have to.
Try using it as a complete system as in the instruction manual and see how you get on - your blades should come out sharp.
If you do use it as a complete sharpening system you may want to use a steeper 30 degree angle.
Cheers
Gidon

 

[Derek Cohen (Perth Oz)]

Gidon

The problem with going from a grind to the strop on the Tormek is not that you cannot get something that looks and feels sharp. The problem is that you cannot guarentee that the edge is straight (ignoring the additional need to add camber). You will likely end up with a wavy edge (no, you cannot see it - but the wood can). Your suggestion may be fine for bench chisels or even a jack plane but not for a smoother. Further, unless you strop away all the serrations from the best surface possible from a Tormek (220 grit converted - one hopes! - to 1000 grit), all you end up with up with are polished serrations. OK for a chisel, and not OK for a smoother.

One of the purposes of a smoothing medium - I use waterstones - is to level and smooth the serrations. Once the iron's edge is flat, then you can add camber. Add your microbevel then if you will.

Hey, I have a Tormek and use it all the time. My sharpening station ...

Regards from Perth

Derek

 

[matthewwh]

Following the tormek instructions will give you what Norm calls 'a good sharp chisel'. If you want to go beyond that, to what most cabinetmakers would call a good sharp chisel, then secondary bevels (be they coplanar or slightly steeper) are essential and will save you an awful lot of time and effort.

The reason for a secondary bevel is that it enables you to treat the last bit of the primary bevel seperately from the rest of it. If you are hand honing you generally end up with a flat primary bevel, so to isolate the first mm or so for polishing you need to increase the bevel angle slightly. As you are using a wheel to grind the primary bevel it will end up slightly concave, so you can polish with both the tip and the heel in contact with the honing and polishing media to create a coplanar bevel as Derek advocates. I was sent a chisel a few months ago that Michael Huntley (editor of F&C) had honed, and he uses exactly the same technique. The only exception I can think of would be if you wanted to alter the cutting characteristics of a bevel up plane iron.

 

[Chems]

First off, thanks for the wealth of info, secondly with just a primary bevel and polished on the wheel free hand its like a completely new tool for me. My chisels are razor sharp and so are my plane irons. The Tormek manual says you don't need a secondary bevel because its so easy to re-hone the primary bevel with the wheels. I'll re-grind a few to a slightly higher angle and see how they go. I've even managed to flatten the backs of the chisels on the side of the wheel which I thought you couldn't do before I bought but the manual says you can.

 

[Caruso]

Do not use the Tormek to flatten the backs of your chisels. The side of the wheel will not stay flat and there is no tool to flatten it. Yes it will work fine for flattening a few chisels on a new stone but after a number of chisels you will gradually realise that your flattened chisels are convex. Been there... done that...

Nowadays I use a coarse diamond stone (if needed) and then water stones to flatten the backs of chisels and plane irons but I still use the Tormek for the bevels.