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JohnM Martin
12-12-2023, 9:55 PM
These are probably some elementary questions, but I thought I would give it a try. I'm thinking/planning out my first real casework project with dovetails - a simple hanging tool cabinet. As I think about this build there are a couple of questions I'm hoping to get answered before I dive in.

1. How do you align the tails (assuming tails first) onto the pin board for tracing the pins with larger panels? I've done some dovetails with small boxes and drawers and have used the method with the plane on its side and a chisel to get things lined up. That seems like it will be much harder to do with a panel that is much wider.

2. This is more of a curiosity than anything else, but the other day I happened across a video on youtube where someone was using a clamped board as a fence/guide for chopping out the waist to the baseline. I was curious about this so I dug through some books and found this picture illustrating the idea.

511978

I tried to put this into practice on a small box and found that (at least for the small piece), the fussiness required to get the fence to stay perfectly aligned while applying clamping pressure just wasn't worth the effort. As I would tighten the clamps, the fence would want to skate across the tailboard (slightly) throwing it out of perfect alignment. I haven't cut a lot of dovetails, but I know enough to know that this is a critical spot for avoiding gaps so I just gave up on the idea. I'm wondering if others use this technique and if there is any reason to prefer it vs just chopping to the baseline without it. If so, how do you get the fence aligned without it skating across the board when you tighten down the clamps.

Thanks in advance!

Daniel Culotta
12-12-2023, 10:51 PM
Clamping a fence sounds to fussy to me, too. You can get really nice baselines with the method Derek details on his site by deepening the baselines, taking a chip out of the waste side, and making a chisel wall. If I’m going to spend any extra effort on chopping to the baselines, this is the method I use. https://www.inthewoodshop.com/Furniture/ThroughDovetails3.html

For alignment, similar method. After you’ve removed the waste between the tails, score the baseline deep on the inside of the tail board. Take a chip out on the tail side of the line to create a wall. This won’t show because it’ll be inside of the joint once assembled. When aligning the boards, tilt the tail board slightly up toward you (i.e. end you’re aligning is slightly higher than the end further away from you). This way the little shelf/wall you created will catch on the inside edge of the pinboard and be in alignment across its width. This plus the chisel/plane method on the edge will get you dead on. I think Matt Estlea did a video on this that makes it really clear - it’s not nearly as complicated as I make it sound.

There are many other methods that work, but these are what I use.

Derek Cohen
12-12-2023, 11:16 PM
Thanks Daniel.

John, here is another tape method I came up with. It is to align boards when transferring marks. Rob Cosman now uses it all the time in place of the "#140 trick".

https://www.inthewoodshop.com/Furniture/The140TrickisDead.html

It was needed when transferring marks for compound dovetails, seen below ...

https://i.postimg.cc/43N3PxQq/ApothecaryChestWeekend8_html_4340d04c.jpg (https://postimages.org/)

Regards from Perth

Derek

Scott Winners
12-13-2023, 12:48 AM
I read somewhere that every wood worker has 300-500 bad dovetails in their hands. All you go to do to start making good dovetails is get those 300-500 bad ones out of your hands into some cheap scrap wood.

Pic is some little trays I made for some of my planes that were good enough to stay out of the fire pit. A few of my early attempts did go to the fire pit, but they aren't inside my hands anymore.

I do use Derek's blue tape method for marking up my pin boards.

If you have resaw capability you might could find a decent 2x4 and make a pencil box out nominal 3/4 inch stock, inside opening maybe 2x2 inches, just 4 walls dovetailed, nail a scrap of plywood on the bottom, voila, pencil box for the workshop.

Sorry, just re-read, you have made some small things, it is inside your question one. To align a wider panel I use a a piece or two of construction lumber planed s4s. Every once in a while I see a perfectly quarter or flat sawn Doug Fir 2x4 at the home store and I routinely bring them home. The one I can get to easiest is about 24" long. When it is time I line up the tail board in my vise flush with the top of the special 2x4 sitting on the bench top. When the vise is tight, move the special 2x4 back far enough the tail panel can span between the pin panel end grain and the special 2x4. Mark it up and go. This is where having your bench top flat and square to your bench face can save many headaches.

Scott Winners
12-13-2023, 1:13 AM
To your question one, here is a quick pic. Bench surface is Doug Fir sap wood, my leg vise chop is DF heartwood, but I got a stick of red oak in the vise. My special 2x4 is flush with the top of the red oak at the front, but pushed to the back of the bench. I got a piece of SPF up on there to represent the tail board. As long as your 2x4 has parallel edges, you are limited only by the length of lumber you buy; and the size of your bench.


For your second question I am in agreement with previous posters to start with a knife line with a straight edge held in the right place, deepen the knife line with the knife. Then cut out some from the waste side back to the knife line with a chisel, deepen the existing knife line with a chisel, carve out a little more from the scrap side. The main thing I can think of is to be gentle with the first cut and only ramp up your knifing judiciously. How much force you can apply is going to vary by species, vary by individual trees within a species and sometimes even in the same board. Just like getting to Carnegie Hall, the best directions are "practice, practice, practice."

JohnM Martin
12-13-2023, 8:10 AM
Thanks, Derek. What a great write-up. Blue tape to the rescue!

JohnM Martin
12-13-2023, 8:14 AM
Thank you for the demonstration. That looks like a good approach. And you are right, practice makes perfect... err, at least better.

Jim Koepke
12-13-2023, 4:49 PM
1. How do you align the tails (assuming tails first) onto the pin board for tracing the pins with larger panels? I've done some dovetails with small boxes and drawers and have used the method with the plane on its side and a chisel to get things lined up. That seems like it will be much harder to do with a panel that is much wider.

2. This is more of a curiosity than anything else, but the other day I happened across a video on youtube where someone was using a clamped board as a fence/guide for chopping out the waist to the baseline. I was curious about this so I dug through some books and found this picture illustrating the idea.

For marking the pins with larger panels, it helps to have the pin board clamped to the bench so the tail board can be aligned properly. Make sure the tail board is square to the pin board not only in the outside face planes but also that the edge of the tail board is square to the face of the pin board.

The only time a guide is clamped to my tail board is with smaller panels for marking the pins.

511996

This is from an old post > https://sawmillcreek.org/showthread.php?259750

The fence for chiseling can cause more of a problem at times. The wedge action of the chisel has a tendency to push the fence back away from the base line. This can cause unwanted gaps.

jtk

Norman Pirollo
12-13-2023, 6:41 PM
This is what I use to transfer tails to pins and also for chopping. The fence moves up and down in threaded posts so alignment is fairly quick. Posts are spring-loaded for quick clamping. Also, a piece of sandpaper under the cleat helps considerably with friction grip. I have been using this type of dovetail jig for 15 years. Of course, although there is a limitation to the width, it does handle most widths.

512001

Jim Koepke
12-13-2023, 10:27 PM
Also, a piece of sandpaper under the cleat helps considerably with friction grip.

That might help John with his method if he wants to continue with it.

jtk

Derek Cohen
12-14-2023, 8:40 AM
These are probably some elementary questions, but I thought I would give it a try. I'm thinking/planning out my first real casework project with dovetails - a simple hanging tool cabinet. As I think about this build there are a couple of questions I'm hoping to get answered before I dive in.

1. How do you align the tails (assuming tails first) onto the pin board for tracing the pins with larger panels? I've done some dovetails with small boxes and drawers and have used the method with the plane on its side and a chisel to get things lined up. That seems like it will be much harder to do with a panel that is much wider.

2. This is more of a curiosity than anything else, but the other day I happened across a video on youtube where someone was using a clamped board as a fence/guide for chopping out the waist to the baseline. I was curious about this so I dug through some books and found this picture illustrating the idea.

511978

I tried to put this into practice on a small box and found that (at least for the small piece), the fussiness required to get the fence to stay perfectly aligned while applying clamping pressure just wasn't worth the effort. As I would tighten the clamps, the fence would want to skate across the tailboard (slightly) throwing it out of perfect alignment. I haven't cut a lot of dovetails, but I know enough to know that this is a critical spot for avoiding gaps so I just gave up on the idea. I'm wondering if others use this technique and if there is any reason to prefer it vs just chopping to the baseline without it. If so, how do you get the fence aligned without it skating across the board when you tighten down the clamps.

Thanks in advance!

One more method - using the Moxon Vice to hold panels for a case.

Planning out the position of dovetails ...

https://www.inthewoodshop.com/Furniture/ApothecaryChestWeekendOne_html_14712867.jpg

https://www.inthewoodshop.com/Furniture/ApothecaryChestWeekendOne_html_m6c39abd9.jpg


Planning for mitred through dovetails ...

https://www.inthewoodshop.com/Furniture/EntryHallTableForANiece2_html_m50d657dd.jpg

Transferring marks ...

https://www.inthewoodshop.com/Furniture/UnderbenchCabinet1_html_36de34ec.jpg


Using clamps in a track to hold the boards ...

https://www.inthewoodshop.com/ShopMadeTools/TheLastMoxonVise2_html_m240a82df.jpg


The fit ...

https://www.inthewoodshop.com/Furniture/UnderbenchCabinet1_html_m1b46258.jpg


Regards from Perth

Derek

JohnM Martin
12-15-2023, 12:45 PM
Thanks, Derek that is very helpful... and your dovetails look A+