Thursday, August 6, 2015

PM2.1.2.1

It rained today. Like lots. Like the whole August rain in 24 hours. Thanks global warming.

So it was a bit of a computer day for me. I tried to make problem 2 of last project mayhem etude, and man it's not that easy. Took me like 4 hours plus a bit more here, and there... kind of the whole day thinking on how to mark these things so they all line up and don't have to cut the joinery twice, not that it already happened to me twice already. Maybe more.

But I cannot make mistakes this time, we just don't have enough wood so everything needs to be in the place it needs to be.

Ok, I just found another mistake in what I draw, but whatever, this is for learning so I'm learning by mistake. I mean, I'm mistaking, let's hope I learn from them.

First thing, we need to have (or learn?) an standard to mark the joints, I started marking where to cut, but some mortices are blind and others no, so you need different signs for those.

Anyway, here it goes:
First the plan so you remember the position and labels of the parts


 Let's start with the 1 line. Ok, I found another mistake, I put the mortices for the small fence pointing the wrong direction.  I wanted to have a wedged tenon but with a dovetail insert, as we did a few weeks back. Now I realise this doesn't work because I want to put the small fence after the structure is up so the tenon cannot go in :/ Also, the corner pillar should have mortices west and south, not east... man, what was I thinking. The upper part is through mortice while the dovetail is blind, that's where I need another sign.

II hope these are better:



 The fence goes E-W direction and only in A2 in both sides, that good. That was relatively easy.

Upper horizontal beam. Labeled 1 because I want to measure everything from the top, use story sticks and then cut down or play with the foundations to get everything level.

I added a splicing joint because the length is not enough. I like how they look open. To connect to the pillars I chose a shouldered open mortice and tenon. I think it gives more strength.

The lower horizontal is simpler, a mortice pegged, and maybe I don't even need the splice. In A1 there is a lap to receive the one going from B to A. I didn't know how to draw that, I want to have a double plug, that's why I chose it as homework last week, but I don't know how to diagram those pieces... are they the same? you draw female and male apart? It was just too much.  

What else? There are no measures here. I need to check that before continuing and remember to use the centre lines.

Man, I'm confused. I need to re-do this tomorrow morning. And maybe start using a proper software, keynote is definitively not the best for joints drawings.

I still need to cut that joint, finish the bench, prepare the blades for tomorrow and give another class saturday. I really have no idea how far I will get with this build in this 3 weeks.

5 comments:

  1. On the shouldered open mortise and tenon that you are using to connect the post to the top sill beam, what about stopping the mortises so that the end grain of the side tenons is not exposed?

    I sketched my design out a couple of days ago, the joint that I had mentioned about "cogging" is on the same page as katasage ari, but for a through beam. Sorry, haven't had a chance to draw each beam out, but maybe this will give you another view.

    I'm going to send you an email with my sketches

    Also, how about moving the of the top sill splice such that it is centered over a post.

    You've picked a great little project to learn this, I'm thinking along the same lines. Keep up the great work, I'm loving it!

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    1. thanks for the sketches, cogged will be.

      I'm really struggling with the design, so I guess it's a good learning experience, hopefully also for the others.

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  2. Ah, just realized that you would have to get very creative with the joinery on the splice if you used the open mortise and tenon, I see why it is to the side. Maybe an interesting challenge? Using both in the same space and the wedges that tighten the scarf also lock the post to the sill.

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    Replies
    1. Actually, I just read somewhere not to put the splice on the pillar, but now I cannot find the reference, so I may be wrong also... plus, I wanted it to be visible and show off :P

      Delete
  3. Posts may generate in drying, twisting force, which if contained in solid wood, will not twist. A splice will not contain the twist, reliably.

    One more thing to look for when selecting wood.

    ReplyDelete