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scott pollack
10-21-2003, 9:11 PM
can anyone offer advice as to the best way to cut the pins on the half laps? and what is the best way to chisel out the bottom of it? im confused on this and would like any help i could get. im ok with cutting through dovetails but the pins on the half laps are getting to me.

are there any books or videos that would be good? thank you all for the help in advance. i really appreciate your time. scotty

Richard Gillespie
10-21-2003, 10:46 PM
can anyone offer advice as to the best way to cut the pins on the half laps? and what is the best way to chisel out the bottom of it? im confused on this and would like any help i could get. im ok with cutting through dovetails but the pins on the half laps are getting to me.

are there any books or videos that would be good? thank you all for the help in advance. i really appreciate your time. scotty

I've only cut these once for a set of 5 drawer. I believe they are called half blind dovetails though. The pins were easy. I cut those just like through dovetails. However. when marking the pins prior to cutting, you must decide how far back from the "face board" You want the pins to fall and thereby reduce the depth of the pin accordingly. I used 1/2" high pins with a 3/4" face board having the 1/4" to minimize any tendency for blow out when chiseling out the tails.

The tails were harder. After marking the location of the tails from the pins, I used a dovetail saw to cut the tails but could only cut at an angle approaching 45 Degrees. That then required using sharp chisels to remove the waste. This was doubly hard in my case because the face board was maple. The only reason I did it this way is because that's the way Roy Underhill showed on one of his episodes.

If I can be of any further assistance email me at richard-gillespie@comcast.net.

Rick Gillespie

Martin Shupe
10-21-2003, 11:16 PM
I think Ian Kirby's dovetail book covers this topic well, but I can't find my copy right now.

Does anyone else have a copy that they can look this up in?

Alan Turner
10-22-2003, 12:15 PM
Scott,
I cheat a bit, but it works well for me. I lay out the pins and cut them first. Cut the sides of the pins by hand at a 45 deg. angle, or whatever angle is needed to cut to both extremes, but no more. And then (here is where I cheat) I freehand rout most of the waste using a 1/4" spiral upcut bit. I do this becuase depending upon the grain fo the drawer fron and which way it is running, it is easy to get a run int he grain which will leave you with a not bery well established bottom. I needs to be tight.
Then I establish the sides of the pins by using a scraper, and pounding it in a bit at a time, suing the saw cut to register it. I have a dedicated scraper for this process, but you can use a good one if you use a wood block to protect the top of the card scraper. Then I chisel slowy to the back line. About 1/32" each cut, so I don't end up severly undercutting the back of the pin. Then mark and cut the sockets as usual.
Alan

Tom Scott
10-22-2003, 1:32 PM
Scott,
Cutting pins for half-blind DT's - Like others have said, you saw at an angle until you hit both of your reference lines, one at the base of the pins and the other at front of the pins. This will get you about 1/2 of the way. Then use a card scraper about the same width as your saw kerf, and hammer it in to form the 90 degree angle of the inside corner. Be careful with this method, though, on the half-pins at the top and bottom of the drawer. If the half-pins are too narrow it may split the wood. However, I found that if I use the card scraper technique and start with the middle pins, saving the outside half-pins for last, there is enough give to the inside of the board that it won't split to the outside. After this, the waste can then be easily chiseled out as normal.

Good luck,
Tom

scott pollack
10-22-2003, 7:26 PM
first off, thank you all for the help. it deffinitely clears some things up. now, if i understand right, i need to cut the pins first? i normally cut the tails first but this needs to be opposite then?
scotty

Tom Scott
10-23-2003, 8:43 AM
Scott,
Correct. I, too, would normally cut the tail board first. But for half-blind DT's I cut the pins first because it seems a lot easier to mark out this way.

Tom

Jeff Kurtz
10-26-2003, 11:18 AM
Scott,

Check out Jeff Gorman on this. He covers both approaches (i.e. pins first or tails) and gives the shortcomings and advantages of each. Here's the link. http://www.amgron.clara.net/index.html

There are also several good videos available. I prefer Jim Kingshott's which is available from Cambium Books, among other places. http://www.cambiumbooks.com/books/joints/1-892836-03-3/

Although I haven't yet seen it, the video Tage Frid made for Fine Woodworking is supposed to be excellent. http://www.taunton.com/store/pages/014004.asp

Don't get frustrated. Get out some scraps, spend a couple evenings practicing, and it will become second nature to you!

Jeff

scott pollack
10-26-2003, 12:22 PM
thank you jeff, id like to get a book or video to keep as a reference so that really helps. scotty