Making a Marking Gauge

[Joe]

I'd like to make or modify a marking gauge specifically for thicknessing and was thinking of following John Nesset's article for Fine Woodworking where he shows how to make a Kebiki. My question is: if you use a single bevel knife blade and angle it such that the cutting edge points away from the gauge stock by a few degrees, to pull it into the work-piece, will you end up with a slightly bevelled arris? I'm having trouble visualising the geometry...

 

[mr]

If you arrange it so that the bevel faces uppermost - ie towards the face being thicknessed then the resulting bevel in the gauged line will be removed by the process of thicknessing.
Not sure I made that very clear - hope it helps some.
Page 17 of David Charlesworth's first book explains it very clearly.

Cheers Mike

 

[Joe]

Thanks Mike. I assume you are talking about positioning the knife such that the bevel ends up on the waste side of the gauge line? This is exactly what I want to achieve (I've been trying to use a Veritas wheel gauge up till now which does exactly the opposite of course). I just wondered if the tendency of this arrangement to push the gauge away from the work-piece could be countered by pointing the knife away from the gauge stock slightly? Or would this result in a gauge line bevelled on both sides?

Joel

 

[mr]

Exactly, for marking a board for thicknessing the bevel should face the waste, but this means that the blade / pin is then the wrong way round for marking rebates etc because in that case the bevel isn't facing the waste. I'm conscious of not really making this very clear and being a bit wooly headed this morning. DC 's book explains it very well if you're passing a book shop or library it' worth a look.
I don't know the Veritas tool you mention but is it possible that the cutting wheel can be mounted either way round? I would think it likely.

Cheers Mike

 

[Joe]

What you say Mike is perfectly clear, I think it's me that's not really explaining myself properly. My desire to make a gauge comes from reading DC's article on marking out in Furniture & Cabinet Making, so I understand the issue of needing gauges with knife bevels oriented both towards and away from the gauge stock. What I'm really trying to fathom is this: in the article by John Nesset that I referred to earlier, he advocates setting the knife out of square in relation to the gauge stock (in the horizontal plane) , the idea being that the knife will then pull away from the stock, thus pulling it tight against the work-piece. But, if you twist the knife a little in this way, will the back edge of the blade drag against the edge of the gauge line and create an unwanted bevel?

Joel

 

[mr]

If I understand you correctly and not having read the article you refer to I suspect that the track created by an our of square blade may be wider than otherwise but I wonder whether it's an issue if the bevel is facing the right way as the width of the track will be wasted away in the thicknessing process until you arrive at your mark. The distance from fence to trailing edge of the out of square blade may not match the distance from stock to cutting edge which might affect your laying out though depending on how you set up your gauges.

Cheers Mike

 

[Joe]

Thanks for your persistence with this one Mike! Following your point about the width of the gauge line I guess the answer to my concern is simply to measure the gap between the gauge stock and the back edge of the blade, rather than the cutting edge, when setting it up.

Thanks again

Joel

 

[mr]

I would have thought you would want to measure the distance between the fence and the cutting edge which would be the greater bu a miniscule amount.

Cheers Mike.