Back bevel

[Chris_belgium]

I'm using a back bevel for the first time ( clifton 4 1/2), I'm used to sharpening free hand till I feel the wire edge and then remove it on my 8000 stone. Have had great results an nice shavings with this technique, but have been planing a load of aphselia lately and that wood takes the edge of very quickly, after some research on this forum I decided to try out a back bevel, but been having problems touching up the edge.

When using a back bevel, how do you remove the wire edge?
-A quick freehand swipe at approx 10°? (using a 10° back bevel),

- Mount it in the sharpening jig and hone the back bevel?

-Just leave it in place?

Just for the record, without the back bevel i could approx plane 150cm 14cm wide board and then had to resharpen, with a back bevel I could to 500 cm by 14 before have to resharpen! What a difference a couple of degrees make!

Thanks.

 

[matthewwh]

Hi Chris,

Personally I use a guide.

By happy coincidence rather than design, I can invert my guide without adjusting anything and get a one or two degree back bevel (ruler trick) laying the back of the blade on the edge of the glass. If I stick something under the guide (in my case a thinner piece of glass I keep under the bench) I get a nice accurate and repeatable back bevel.

 

[Chris_belgium]

It's abit of a hassle to mount it in the guide everytime I have sharpen it, especially with the aphselia since it looses it's sharpness quite fast, but guess there's no other way.

 

[David C]

Chris,

I have worked with Afzelia quite a lot.

It can have exceptionally difficult ionterlocked grain and is full of mineral deposits.

We used to use a 20 degree back bevel, applied with an Eclipse type jig. These are quick and easy to fit and the back bevel need not be very wide. 0.3mm is enough.

So here is my suggestion.
1. Sharpen the bevel on your coarse stone. Freehand.
2. Set the blade upside down in the Eclipse guide at 20 degrees and take a few strokes on the coarse stone. Just enough to produce a wire edge on the bevel side. (Edges wear on both sides)
3. Polish the back bevel on the 8000 stone.
4. Polish the wire edge on the bevel side freehand.

best wishes,
David Charlesworth

 

[Karl]

Chris

Check out this thread for a cunning way on easily applying a back bevel to a blade.

Cheers

Karl

 

[Chris_belgium]

It's a wierd wood this afzelia, when i look at it, it look's very straight grained, but it isn't. It planed quite easily with the clifton plane, but i think that is more a compliment for the quality of the plane than my very limited planing experience. But on some small patches in the wood, without any visible reason, I got huge tear out and chattering, probably the grain wich has changed.

Adding a back bevel prolongued the 'life' of the edge by a great deal, without back bevel I could only do a 150cm board, with a back bevel I could do more than 500cm.

For the rest of my project I will try the suggested 20° back bevel.

https://www.ukworkshop.co.uk/forums/viewtopic.php?t=34019&start=30

Thanks for the advice!

 

[David C]

Chris,

Do tell us how you get on.

Karl, love the two guide setup!

David Charlesworth

 

[mark w]

I just looked at Karl`s thread and it confirms what I always thought, you can always tell if a craftsman knows how to sharpen a blade just by looking at his fore arms, if he does there`s no hair!

Mark W