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Half Blind DT

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Half Blind DT

#1

Half Blind DT

Joe in a Cleveland suburb


>Hello.

I'm getting ready to make a drawer for this little cabinet. This is the walnut cabinet some of you have helped by answering some planing and sharpening questions and so on. So it sorta qualifies as a hand tool project. Well, it's been a mix of hand tools and power tools...

Anyway, I want to do half blind dt's on the drawer. I'm going to use the steps outlined in FW #185 August 2006. I've had some success with through dt's on other things so I'm not a complete noob on dt. I have an Adria dt saw and I use a knife for marking. I do have a couple questions though:

1 - I don't remember, should I saw to the waste side of the mark or on the mark?

2 - How should I lay out the dovetails? I kinda remember seeing a pattern someplace or a trick where you measure across the board or something? How should I do this?

Thanks!

Joe

Re: Half Blind DT

#2

Re: Half Blind DT

Denis Ch�nard, Orl�ans, Ont.


>Seems like there are as many ways to do dovetails as there are woodworkers, but here's my take:

"1 - I don't remember, should I saw to the waste side of the mark or on the mark?"

Leave the mark. And them some. It's always easier to trim some wood off than putting some back in. Note that this applies to the second part only (pin or tail board, depending on what you start with). The first board you can cut on the mark, it doesn't matter, it's when fitting the second part that you have to be precise. Notice that in most DT demos the woodworker usually hammers the joint home with a block and hammer, you wouldn't need to do that if the joint wasn't tight...

"2 - How should I lay out the dovetails? I kinda remember seeing a pattern someplace or a trick where you measure across the board or something? How should I do this?"

If you want to make consistent dovetails, one nice trick is using a set of divider calipers like Cosman does. Start with the tail board, determine the size of the half-pin waste at each end, and adjust your divider to that size. make an indentation at each end of the tail board, on the end grain. Then adjust the divider to give you the number of tails, and "walk" from one half-pin mark to the other (but don't leave marks. So if you want three tails, walk the divider three steps, you need to get past the other half-pin mark. The distance past the half-pin mark determines the pin size. Adjust the divider until you're satisfied with the pin size, and then walk your divider one last time, this time leaving impressions in the wood. Do the same thing again from the second half-pin mark back to the first one, leaving impressions in the wood again. Make a square line at each impression, and you have your tails laid out.

It's much more difficult to describe the process that to do it...

HTH,

DC

Re: Half Blind DT

#3

I'm confused.

Joe in a Cleveland suburb


>Thanks Denis, but I'm confused. I'm trying to digest what you wrote and understand it. You said determine the size of the half-pin waste at each end. How do you determine that size?

Suppose my drawer front is about 5 inches wide. Do you just pick a size you think looks good?

Thanks.

Joe

Re: Half Blind DT

#4

Yup!

Jim Shaver Oakville, Ont.


>Hi Joe,

I pick my half pin sizes by eye, they tend to be about 1/4" in my case, then I use the divider method that Denis described that Rob teaches...takes less than a minute for me to lay them out.

Take care,

Jim

Re: Half Blind DT

#5

If you're grooving the drawer side by hand...

Paul Kierstead


>then you might want to pick the half pin size (and groove position) to make sure the groove passes fully through the first tail (watch out for the bottom of the tail, it is narrower...DAMHIKT), allowing the groove to be the entire length of the side (and front) and save you doing a stopped groove.

Of course, if you are using drawer slips...

Re: Half Blind DT

#6

Re: I'm confused.

Denis Ch�nard, Orl�ans, Ont.


>That's it, pick what you feel looks good, but leave the half-pin wide enough so that it retains some strength. Klausz uses half the thickness of the board as a rule of thumb.

Paul's advice is important too. If you can manage to get the drawer bottom groove to go through a tail, then you save yourself some work. Otherwise you'll have to make stopped grooves.

DC

Re: Half Blind DT

#7

Re: If you're grooving the drawer side by hand...

Jim Shaver Oakville, Ont.


>Great Point Paul,

That is really the truth...I sort of have my standard drawer bottom sized and dimensioned to fit my choice for half pins, you said it, you only have to do it once where it shows to make the change to hide it on your next set of drawers.

Take care,

Jim

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