Hi everybody.
Has anyone given a go at making one? I mean making a dovetail jig like the ones of arunda or lignatool, for setting joists or purlins. I've done a youteub search, to no avail.
Anybody?
Thanks a lot.
Max.
Hey Satamax,
Read this FF post thread, then come back here if you have questions/comments. ;)
https://forestryforum.com/board/index.php/topic,59968.msg918504.html#msg918504 (https://forestryforum.com/board/index.php/topic,59968.msg918504.html#msg918504)
Regards,
jay
Thanks a lot Jay.
But, it's not answering my question. For some reasons of productivity, I'd rather do dovetails. It's for my own workshop and flat above. And I will need to get it up real fast. And somewhat on my own.
The joints you've showed in that other thread aren't that long to make with a chain mortiser and router, chisels or circular saw. But they need to be fitted while raising. I doubt I could fit fifteen joists and four purlins while raising, even with the help of a few friends. Usually, I nail a batten at the bottom of the tie beam, and rest the joists on top of it, then cross nail the bottom and nail the top of the joists. The purlins resting on the principal rafters, and the ridge being inserted in the king posts.
I want to try the flush mounting of the purlins with the principal rafters, for insulation purposes, as it makes my life easier. You know, I haven't cut that many whole frames either. Being more used to repairs and redoing roofs. Mostly sarking type.
Hello Satamax,
You wouldn't put a soffit or tusk tenon on each joist, only in the mid span area to keep the frame pulled together. I can't recommend the "routed and dropped in" dove tails made with those jigs. Would I use them, maybe in some cases, but I only recommended seasoned and well initiated timber wrights use them. They work great one way, and are really bad in all other configurations. They also do not preform well in green wood. The only place I have seen them used, (and liked them,) is in kiln dried Douglas Fir and some reclaimed timber. Those frames also incorporated "soffit tenons" at the mid span.
I you could give us a peak and your design in "sketch up," or a simple bent drawings, it would help visualize what your plans are.
Regards,
jay
Latest drawing.
Braces not drawn yet, between the bents. And roof not done with flush purlins.
Some older screen-shots. I lowered the workshop ceiling, as I was too high for code.
https://forestryforum.com/board/index.php/topic,57682.msg848424.html#msg848424
O.k. I don't do oblique braces much anymore, so I kind'a let other folks stay with the European Design assists. I think you should check out this post thread, you would get a lot out of it:
https://forestryforum.com/board/index.php/topic,63364.0.html
You have many items that could make the frame easier to cut. For one you don't need the principle rafter and a queen post assembly. Over all it looks nice.
Good Luck,
jay
Quote from: Jay C. White Cloud on February 12, 2013, 10:39:43 PM
O.k. I don't do oblique braces much anymore, so I kind'a let other folks stay with the European Design assists. I think you should check out this post thread, you would get a lot out of it:
https://forestryforum.com/board/index.php/topic,63364.0.html
You have many items that could make the frame easier to cut. For one you don't need the principle rafter and a queen post assembly. Over all it looks nice.
Good Luck,
jay
Thanks Jay for the reply. What do you mean? by I don't need the principle rafter and queen post. I would say this is more like a Palladio bent. You're talking about the stub king post? Anyway, at first, I was gone for something like this.
https://forestryforum.com/board/index.php/topic,52390.msg755664.html#msg755664
But I'm going astray. I really like the flush purlins for insulation purposes.
Sorry about that,
I mean you only need one or the other, not both. Your reference is what "cruck frames," turned into. I do folk styles and love "cruck frames," I don't do what they turned into. We build double roofs on many of our frames, and work in an Asian style, so the queens hold up the purlin that you see on the outside and then there is a second purling visible on the inside, with the insulation in between. Our building system (truss walls,) and Asian folk styles kinda puts us in a unique niche. So most of the time I just answer basic questions for folks. when it gets to this stage of design, unless it's an Asian design, or some other folk style, I try to fall to the background, since there are plenty of folks working in more European contemporary traditions. Do let me know if you think I can help with something, I'll will always respond.
Regards, jay
Cool Jay. Thanks a lot for the offer. You're always welcome on my posts. What you were suggesting earlier, with the through tenon might reveal complicated, as I use a pair of collar beams for the tie beam and first floor crossbeams (is it sill?) In French we use the term sommier, which means any beam onto which the joists ends will bear. Anyway, it doesn't tell me if someone tried to make a dovetail jig :D
Do you use wind braces? You know the ones between purlin and principal rafter.
Thanks.
Max.
Bonsoir Satamax,
QuoteDo you use wind braces?
Sometimes in a roofing frame they will be incorporated but seldom today. So many timber frames are overlaid with another frame to create a thermal/mechanical envelope, so additional bracing is not need.
Your jig...well I don't like the joint they make very much, as I have said, and it kind'a scares me someone using it without understanding all the design ramifications, however, if you just look at the manufactured jigs, you can make a good working copy. I have seen them made with plywood, home made aluminum plate screwed together, and plexi-glass glued together. They work on a center line layout system, or, if the timber is in excellent square condition, you can reference off a side. So if you really want to try this joint, make your own jig and save some $$$.
Bonne chance,
jay