Hand-cut dovetail jig

[derekcohen]

I find this jig useful for marking and for accurately paring the shoulders of dovetails.

It is not used for cutting the pins (which can either be done freehand or with the Veritas jig), but it makes it easier to chop out the waste to the line - and to make sure that all the line cuts are in-line.

There are three pics. The first, below, is a pic of the entire jig. This consists of a clamp, a fence, and a movable stop on a board.

Regards from Perth

Derek

[derekcohen]

In the next pic you can just make out a board in the jig (unfortunately, it is a pine drawer side on the pine jig). The pins are up aginst the stop, the side is against the fence.

The fence and the stop ensure that everything is repeatedly square. You can turn the board over repeatedly without losing your place). I am paring one of the shoulder cuts.

[derekcohen]

In the last pic, below, the movable stop has been removed. It is now being used to measure and mark the boards (prior to cutting).

For those wondering why the pins look so short, it is because they are part of a blind dovetail joint.

[Ben from Vic.]

Just thought I'd let you know that I didn't reply when you first posted this, but I did save the link as I think it's a great idea. :D

[Steve_DownUnder]

Derek

Nice jig... isnt it always the simple things that help the most ?

Nicely finished too, I think that will get put on my long list of things to build.

steve

[jow104]

To Derek Cohen,

Thank you for the link to your dovetail jig posted at the UK woodwork forum.

I intend to build your former today, but could you explain what purpose is the brown inlaid timber performing on attached photgraph .(marked with questin marks)

Many thanks.

http://img.photobucket.com/albums/v330/devonwoody/djig2.jpg

[derekcohen]

DW

The brown inlay is a fence - against which you place the side of the timber.

I do have a modification for this jig. When you build the fence, don't attach it to the base (as in the picture), but rather attach it to the cross fence. That way you automatically line up the cross fence perpendicular to the sides.

The front section is a depth gauge. This allows you to turn the timber over, after chiseling half way through it, and locating the same line on the other side.

Make the cross fence deep enough to act as a guide when you pare/chop the end of the dovetail.

Regards from Perth

Derek

[jow104]

Thanks again and also for the amendment.

quote:-
Make the cross fence deep enough to act as a guide when you pare/chop the end of the dovetail. end quote

I am thinking that the front stop (could have duplicate or sepatate pieces) could also follow my original thoughts on a dovetail jig by making the stop the same thickness as a lip on a blind dovetail, thereby acting as a former for the chisel to lay on when cutting into the end grain.
Your comments appreciated.

[derekcohen]

Woody is relating to another website (http://www.ukworkshop.co.uk/forums/viewtopic.php?t=4686&postdays=0&postorder=asc&start=0&sid=ce65d8e356a7cfed0c12360d03ae0fa0) when he writes:


my original thoughts on a dovetail jig by making the stop the same thickness as a lip on a blind dovetail, thereby acting as a former for the chisel to lay on when cutting into the end grain.

Woody, when I saw your "fence" I first thought it a good idea. However, the problem is that it cannot be adjusted for different shoulder depths, and it is only for end of blind dovetails. But it is a good idea and what I would try out is making a rebated "end cap", and add it to the depth stop when needed. Does that make sense?

Regards from Perth

Derek

[outback]

AAAARRRRRRRRRRRRRRRRRRGGGGGGGGGGGGGHHHHHHHHHH

I had only just got my head around Mark 1 and already you have changed designs, and have further mods in mind.

Post pics and details for your textunderstanding challenged friends please oh master of the dark side. :p

[jow104]

Derek

I think the endstop can be 3 mm thick which is a basic lip thickness but other thicknesses could be stored as standbyes?

or pack up the workpiece to the correct depth/height each time?, with a fixed size end piece.

Again not citicising your jig but wishing to adapt for my purposes.

[derekcohen]

Woody

I have given it a bit more thought and now see your jig differently. You will too if you turn it around 90 degrees!!

Instead of using it in the horizontal, clamp it in your vise and use it in the vertical. See your picture below, which I have rotated 90 degrees, and imagine that it is clamped in the vise.

Used this way it is perfect as a fence for the top end of the pins. You will still need to use my jig to line up the bottom end of the pins.

I think that I will make one for myself!! Well done.

Regards from Perth

Derek

[ryanarcher]

Great Idea Derek! I think you should work for veritas in the tool innovation department. Not bieng a jig person I have a question. do you use this to avoid having the scribed marks left over from the slitting guage on the finished product? I find that on the last paring cut the chisel rides nicely in the knifed line (making a jig redundant). However, I do find that leftover line on the bottom of the tails unatractive.
Cheers,
-Ryan

[derekcohen]

Ryan wrote:


do you use this to avoid having the scribed marks left over from the slitting guage on the finished product?

No, it is not to avoid the scribed lines. I think that they are like a "badge" to indicate that the dovetails were handcut. And I agree, the last cut should ride up in the line - keeps the shoulder nice and clean.

The purpose of this jig is (1) to cut straight shoulder lines (all in a line), and (2) to pare the shoulder vertically (you can undercut it slightly after doing this).

I developed this jig a couple of years ago when I began cutting dovetails by hand. It helped me enormously then. I still use it, but not as regularly.

Regards from Perth

Derek

[jow104]

Woody

I have given it a bit more thought and now see your jig differently. You will too if you turn it around 90 degrees!!

Instead of using it in the horizontal, clamp it in your vise and use it in the vertical. See your picture below, which I have rotated 90 degrees, and imagine that it is clamped in the vise.

Used this way it is perfect as a fence for the top end of the pins. You will still need to use my jig to line up the bottom end of the pins.

I think that I will make one for myself!! Well done.

Regards from Perth

Derek


Derek, I have completed the make up of your jig and today I await delivery of a new set of metric bevel chisels plus a japanese dovetail saw.

Have you done a trial run on my version of the jig for the lips yet?
Wanting to see your comments, I'm thinking along the lines of using some old kitchen formica top as the former, thought it might provide a nice flush guide for the chisel as well as a straight line.

[derekcohen]

Woody

I will try to get to it this weekend.

Regards from Perth

Derek