Replies

1. 
   domermatt | Oct 27, 2005 04:42am | #1

   I pound the old saw, like Frid instructs too.

    

   Crude?  The end result counts, and I would say that Mr. Frid produced some high quality dovetails.  I don't have any problem pounding an old piece of metal into some expensive cherry that will end up being part of a reproduction secretary.  I'm looking to make the best piece of furniture I can with least amount of time expended as possible.

    

   When people 100 years from now see my work, they'll know I cared. --Matt Mulka
2. 
   BlueEnamel | Oct 27, 2005 05:02am | #2

   FWW had an article on dovetailing a drawer by Janet Collins a few years ago. It does a great job explaining the task. There are a few tricks though.

   You are correct about the saw doing only half of the job. The remaining wood is removed with a chisel. There are a few tricks though. The first is to use the part that the saw cut to guide the chisel. Also, remove a small section of new (non sawed) wood at a time. Like paring through dovetails, pare across the grain of the wood, not with or against it. You have much better control over how much wood is removed since you're removing wood perpendicular to the grain. There is no tendency for the chisel to dig while paring.

   The second trick covers how to clean up the inside corner of each of the pins. The key is to use a skew chisel, or even better, a 1/2" chisel ground so that it has two edges pointed at about 60 degrees (looks like like an equilateral triangle from the back of the chisel). Sharpen those edges like a regular chisel (25-28 degree bezel) and make sure you keep the point sharp. This tool acts like a pair of left and right skew chisels all in one package. Pretty nifty. With it, you can pare the far inside corner of each tail. This works on the long grain as well as end grain faces. It works like a charm. Also, since it is only removing a very small amount of wood for a somewhat specialized task, the tool stays sharp for quite some time. I find that sticking the point into a wine cork helps keep it in pristine condition.

   I've tried the Tage Frid method of pounding a scraper into the saw kerf and I ended up splitting the pin board. It also bruises the sides of the pins as well.

   The best advice I can give you for increasing the chances of success are to make sure the edges of the tails on the tail board (side of the drawer that does not have the half blind cuts) are 90 degrees to the end of the board and are that way their entire length. Use a good combination square to check this. Fuss with the tail board until it is perfect. Remember to pare any wood across the grain. This is a key point. You have much better control than going with or against the grain. Once you are satisfied with the tail board, DO NOT REMOVE ANY WOOD from the tail board once you start to scribe and fit the joint. The tail board you fussed over is the REFERENCE board for the joint. If you modify the reference, then there is no reference any more.

   For scribing, I like to use a drafting pencil with a thick lead sharpened into a long knife edge. Once I line up the tail board and have it clamped in place, I scribe around the tails onto the pin board. The next step is to remove the wood between the scribed lines, but LEAVE THE ENTIRE LINE. The reason is that, during the scribing process, you put pencil on the part of the joint that needs to remain. Any pencil line removed removes some of the wood that is needed to make a tight joint.

   There are some more tricks for fitting and knowing which parts of the joint to pare. I can post the rest if there is more interest. I can also post a picture of the "dovetail" tool I mentioned above if requested.

   Good luck,

   -- Blue

1. 
   ktkamm | Oct 27, 2005 05:48am | #3

   Any additional tips/info always welcomed. Picture of the chisel would be appreciated. Thanks, Kieran

1. 
   BlueEnamel | Oct 27, 2005 08:19am | #6

   Kieran,Here's a picture of the chisel. It is a modified 1/2" Marples blue handle chisel. The point is about 60 degrees or so. It was pretty easy to make. The only tricky part is the final grinding near the tip. Since it has a small mass, it tends to lose its temper (turn blue) very easily. The solution is to leave a bit more metal at the tip on one side and hone it off on a coarse stone.-- Blue

   
1. 
   ktkamm | Oct 27, 2005 01:49pm | #7

   Thanks Blue. As you said, looks fairly straight forward to make.Kieran

2. 
   termites | Oct 28, 2005 03:12am | #8

   Thank you for the response.  I will try to locate that article in the FWW archive and order it.  I like your idea of modifying a flat chisel and can see that is a real time saver.  I currently use two seperate skew chisels (right and left) to do the same thing but your method will eliminate a tool exchange.  You indicate that you could also offer some tips on fitting the joint...  Please tell me more.

1. 
   BlueEnamel | Oct 28, 2005 09:13pm | #11

   Here is the process I use for fitting dovetails. It applies to through, half blind, full blind/mitered, etc.I'll start with the assumption that the joint has been scribed on the end of the pin board (i.e. front of the drawer) with the desired amount of lap (usually 1/8" or less, depending on the scale of the drawer). As I mentioned earlier, I use a mechanical drafting lead holder (2mm lead) with the lead extended and sharpened to a long, flat knife edge. I've tried using a knife, but I find that the pencil doesn't follow the grain as much.The next step is to extend the scribed lines from the end of the draw front to the inside, making sure they are 90 degrees to the end of the drawer. The next step is to saw out the waste. Here's the key point: Since the scribing of the joint puts pencil lead on the part of the joint that needs to remain, you need to saw and remove the waste so that ALL of the pencil line remains. If you remove ANY of the line, you're removing wood that needs to be present for a tight joint.Use whatever type of saw you like to make the initial saw cuts. A saw with 18 TPI or better makes a good cut, especially if it is tuned and sharpened for cutting dovetails (yet another side discussion, if interested ). Luckily, for the pins, the end grain cuts are at an angle and the face grain cuts are at 90 degrees. These are easier to cut than the tail board cuts. One trick is to cut both the end and face grain lines simultaneously, keeping the saw angle so that the last saw stroke meets both ends of the cut simultaneously (or close to it). I usually start by getting the saw started on the end grain, then tilt the saw to start the cut on the face grain as soon as I can. By watching both lines and the saw, you can keep the cutting plane even with both lines. Remember to KEEP ALL OF THE PENCIL LINE! Repeat for all of the pin cuts.The next step is to remove the waste. This follows the same process as the tail board. Lightly score a bit away from the waste line across the face of the board with a chisel and remove wood to that score line forming a ramp down to that cut. Continue, making the cut deeper and ramp longer.Unlike through dovetails, the saw cuts do not cut all of the wood. Use the sawed area as a guide for the back of the chisel and remove a small section of wood at a time (around 1/8") until that section is flat. Continue removing wood in a systematic way stopping when you're almost at the bottom of the lap.There should be a somewhat heavy knifed score line to guide the chisel. Now, depending on the wood and what the grain is doing, paring with the grain may cause the chisel to "dive" into the wood, tearing the grain as it goes. This should be avoided. Ideally, cross grain paring would be best, but there may not be much room to do it with standard tools. A VERY sharp chisel and VERY light cuts will allow you to pare against the grain without digging or tearing. Another technique that may help is to use slicing/circular cuts to approach the cut from the side/cross grain while moving forward. Use the dovetail tool or a skew chisel to get into the inside corners. The last step in the bulk wood removal is to do the final paring on the end grain faces at the end of the tail sockets. Make sure the chisel is 90 degrees to the face of the board and pare to the knifed scribe lines. Use the dovetail tool to clean up any bits in the corners. Some very slight undercutting can be done on the end grain and face grain, after about 1/8" of 90 degree surface, to make sure the joint fits well. This undercutting should be less than 1/16". There is no need to go further.Now the fun starts -- fitting the joint.start by coloring the edges of the tails, which will rub against the newly cut pins, with a pencil. Only a small bit of the front part of the edges need to be covered w/ graphite. Next, try fitting the two pieces together just a small bit. They should be pretty tight all around. Take them apart and look at the faces of the pins. There should be graphite on the high spots. Carefully pare only those high spots. Pare across the grain for maximum control.DO NOT PARE THE TAIL BOARD! The tail board is THE reference board that all of the joints were scribed, and cut, to. If you mess with it now, you've destroyed the reference and the joint will never close tightly.Repeat the process, extending the range of the fitting a small section at a time. Don't rush the last 1/8"! Take your time and don't force the joint together with a hammer. I've split dovetails doing that, all because I rushed it. The joint should fit very snuggly, but shouldn't require a hammer for assembly. You may need one when disassembling it, though.Once the paring is done, the joint is complete.Once the rest of the joinery is done, glue and assemble. You only need a small bit of glue for the dovetails. There should only be a small amount of squeeze out. Prefinishing or taping the insides of the joint helps deal with any squeeze out. Also, removing the squeeze out when it has set, but not cured helps. An old chisel with a skewed edge makes a good scraper for the inside corners. You don't need it sharp to remove glue.

   There are some details regarding layout, board orientation, etc., but the construction process is the same. Angled dovetails, mitered dovetails, dovetails at non-perpendicular angles, etc. are all fitted the same way. Just the layout and some cutting details change.
   Also, here's an article that is pretty close to the methods I use. This is one of the best articles I've seen on cutting dovetails. Although it is geared toward through dovetails, all of the techniques apply to half blind ones as well.http://home.comcast.net/~charliebcz/DovetailDrawer0.html

1. 
   termites | Nov 01, 2005 04:28am | #12

   Thank you for the wealth of information.  I found the link to be particularly helpful.

3. 
   Schulz | Oct 27, 2005 05:57am | #4

   A traditional technique is to oversaw your scribe line on the back of the board. You can also use the heel of your saw at the end of your stroke as you're cutting to dig the kerf a little deeper. The kerf will only show on the inside of the drawer. This offends our modern sensibilities but the old timers would probably think we're nuts to waste time to gussy up the inside of of furniture where it didn't really show. To them, a handcut dovetail was just how you put a drawer together, not some mystical hallmark of fine craftsmanship.

   That said, I've done the oversaw technique on a few pieces and every time it felt like nails on the chalkboard. I don't do it anymore and I use Tage Frid's technique, but with spare cabinet scraper instead of a bandsaw blade. I don't try to pound it all the way to the corner, usually maybe 1/2 or 2/3 of the way.

   Also I bought a pair of 1/4 inch Marples chisels and ground them to make a matching pair of skew chisels. Easy to do and helps out big time cleaning out the corners.

   Remember the only parts of your joint that will show is the sides. Concentrate on getting crisp lines there, the rest doesn't matter much. Even a crudely cut dovetail plus a dab of glue is good for at least a couple centuries.

   Steve

1. 
   termites | Oct 28, 2005 03:20am | #9

   I have used the "oversaw" method with great results.  However, I only use that technique when doing casework where the inside of the joint cannot be seen.  Even then it really bothers me.  I would never use that technique if there was any chance the oversaw marks could be seen (drawers, chests, etc).

1. 
   WillGeorge | Oct 28, 2005 08:19pm | #10

   I have used the "oversaw" method ..My Grandpa was a cabinet maker for years and years for the Chicago CTA (I think).. Made/repaired stuff for the OLD street cars.. Way before buses... They had a lot of wood in them.. Some of the seat joints were dovetailed and the outside trim.. Long ago and just little then but as I remember.. On Saturdays I was allowed to go to the shop.. I HAD to be quiet and just 'watch'.. LOL..I think he did that all the time! Or maybe just slipped?

4. 
   bristowbutcher | Oct 27, 2005 06:41am | #5

   I struggled for about a year with this prblem and then I got ahold of the vidio tapesby Rob Cosman, and it was like a light went off.  There are two tapes and they show you step by step and the tricks are all there.  The telephone number is 877-967-5966.   This was the best