Groove or M & T first in a frame?

[Andy Kev.]

Jacob,

yep, it's from Wearing and I find it very helpful indeed.

Yes I'm using a motice chisel and it is my imperfect use of it (allowing in one or two places a slight deviation from square around the axix of the chisel) which led to unevenness in one or two spots on the sides, although I was getting better as I progressed, which is, I suppose, the point of practice.

The idea of centring the markings (which is just thinking out loud really as I suspect it is not practical) was to mark 5/16" mortice lines and then 3/8" lines enclosing them thus giving 1/32" gaps. This would of course require a common centre line for both markings and it is achieving that which I regard as probably impractical. Then cut with the 5/16" chisel and finish to the 3/8" line, the idea being that I would have allowed for a literal margin of error to allow for imperfect wielding of the chisel.

I do have a mortice gauge.

For what it''s worth: my "normal" sized mortices - say up to 1 1/2" deep are usually OK but having once ballsed up 4" deep ones, I'm trying to boost my chances of getting them right. (I don't want to get through half a dozen lots of pine).

Andy.

 

[Jacob]

Jacob,

yep, it's from Wearing and I find it very helpful indeed.

Yes I'm using a motice chisel and it is my imperfect use of it (allowing in one or two places a slight deviation from square around the axix of the chisel) which led to unevenness in one or two spots on the sides, although I was getting better as I progressed, which is, I suppose, the point of practice.

The idea of centring the markings (which is just thinking out loud really as I suspect it is not practical) was to mark 5/16" mortice lines and then 3/8" lines enclosing them thus giving 1/32" gaps. This would of course require a common centre line for both markings and it is achieving that which I regard as probably impractical. Then cut with the 5/16" chisel and finish to the 3/8" line, the idea being that I would have allowed for a literal margin of error to allow for imperfect wielding of the chisel.

I do have a mortice gauge.

For what it''s worth: my "normal" sized mortices - say up to 1 1/2" deep are usually OK but having once ballsed up 4" deep ones, I'm trying to boost my chances of getting them right. (I don't want to get through half a dozen lots of pine).

Andy.

I just don't see the point of Wearing's fiddling about!
NB it doesn't matter too much what the mortice looks like as long as it all goes together accurately, as it's out of sight once finished, unless through - where you'd need to be clean and tidy on the back.
The whole point of the mortice chisel design is that it does the whole job so if you want a 3/8" mortice you use a 3/8 chisel.

You wouldn't expect to find a 4" deep 3/8" blind mortice - there just wouldn't be any point. But you might find a 3/8" x 4" through mortice, in panelling etc. Having marked all around you cut half way (ish) from the face side, then turn it over and cut from the back. They should meet but if not the chisel will find a way. It doesn't matter if it's untidy as long as the visible entry hole on the back is neat

 

[Andy Kev.]

It will be a through mortice and although my practice run was not a disaster, I obviously want to do it as well as I can. That said, I can live with a bit of raggedness as it will be painted in hat end.

 

[Andy Kev.]

Further to the general discussion, here's the Renaissance Woodworker showing how he chops a mortice which is wider than his morticing chisel:

https://www.youtube.com/watch?v=YD2vSgtHsUc

 

[G S Haydon]

Decent enough demonstration, I think in that case I would of found it easier to use a brace and bit and then pare it out. But it worked.

Here's a Korean bloke with a claw hammer and cheap & cheerful chisel https://www.youtube.com/watch?v=rjtHE_QZrdU

How's the lid coming along Andy?

 

[Andy Kev.]

Your Korean man has got the skill, hasn't he? He could probably do it with a log and a piece of flint.

As for the lid, it is, unbelievably about 97.5% done and it was a really useful learning process. I found that because the tenons were about 4" long, the splitting method didn't work as at that length it was very difficult to control the cut. So I took my courage in my hands and sawed carefully, knowing full well that the saw would bottom out about 1/2" short due to the brass back. I finished the cuts with a small backless Japanese saw.

The sawing worked because I know that when I veer off line I tend to go to the right and so positioned the waste side accordingly. I could end up bang on the line on one corner and 1/8" away from it on the other! However, the trusty router plane always came to the rescue.

The four mortices ended up messy but each one was cleaner than the previous one (the old practice thing again) and luckily the design calls for the two front ones to be hidden by the dust seal. Grooving the lid and frame was a doddle and I think the Veritas grooving plane is probably my favourite tool at the moment.

So the upshot is a lid that fits well and snugly and even looks OK from about four feet away. My confidence levels with regards to M & T have gone up and that's in no small part due to the advice from you and the others on here, so thanks again to all.

All I have to do now is source some decent hinges but I'm not too keen on paying Brusso prices, although I'm sure they're good kit.

 

[Paddy Roxburgh]

I found that because the tenons were about 4" long, the splitting method didn't work as at that length it was very difficult to control the cut. t.

Hi Andy, when I split large tenons I do some stop cuts parallel with the shoulder, roughly every inch. this avoids worries about the grain taking the split off course. These are dead quick to do because you don't need to mark them as they don't need to be dead square across or downwards, the only thing is to check you don't saw to deep If you do your splits slightly proud of your layout lines and then pare the across the grain on the inch nearest the shoulder with a chisel the rest of the tenon can be planed across the grain with a normal bench plane, I'd use a 4 or 41/2. I use this method when cutting tenons longer than the 31/2 inches that my tenon saw allows. Once you get in the swing of it it's quick and easy to be accurate.
Nothing wrong with the way you did it, just maybe something to try another time, you might like it.
Paddy

 

[Andy Kev.]

Hello Paddy,

that makes absolute sense: one of those things that seems so obvious you end up saying, "How come I didn't think of that?" I can see the sense of using a plane as well but I suspect that I would want to give the very last touch with the router plane, just to know it's bang on where I want it to be (more a reflection on my planing rather than your method.)

I'll give it a bash on a bit of scrap tomorrow. Thanks a lot.

 

[Paddy Roxburgh]

Unless you have a really large sub base to your router plane then it won't be able to reach the whole length of a long tenon. You could do the first inch next to the shoulder with the router plane instead of a chisel if your worried about the accuracy of your paring with the chisel. If you plane with a bench plane from each side just plane until you touch the marking out lines leaving a slight hump in the middle. You can then safely plane this hump by keeping the plane on the middle of the tenon so it can't go deeper than the edge (well it can but only by the depth of the iron which is ok).
Paddy

 

[G S Haydon]

Good work Andy! Nice tips from Paddy too. I do like the videos on that channel, a bit hairy here or there and would probably be considered inappropriate.

I used some cast butt hinges on mine, seemed to of worked well enough and were ok price wise