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By MarkDennehy
#1057085
Okay, so I figure I could try it myself and make all the fun mistakes and have to re-do it a few times ...ooorrrrr... I could ask here and maybe get an idea that saves me having to order a bunch more 2x4s :D So:

Screen Shot 2016-05-10 at 17.17.59a.jpg


If you were cutting this joint (and the wood would be two laminated 2x4s), how would you do it and what would you be worried about?
(ie. how is the newbie most likely to break the long dovetail-like side piece?)
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By Zeddedhed
#1057095
I'd cut the little tenon first - bandsaw/handsaw/bit of both.

Next would be the mortice - whatever method you favour.

The dovetail-ish piece would be next, cutting the bevels on a table saw, although by hand would work but a bit fiddly due to short strokes.

Last of all I'd do the big housing/slot on the bandsaw, cleanup of all faces with good sharp chisels and a shoulder plane for the tenon.
By Brentingby
#1057098
Where is the glue line between the two pieces of wood? You could probably cut most of it before gluing up. Leave the dovetailed part long enough so you can square up the ends. Then cut it off after gluing.
By deema
#1057100
That looks like some form of Japanese joint, and it would be perhaps intent erecting to explains he application so we can understand the reason for the complexity of the joint.

The sliding dovetail is normally used to avoid the use of glue, however in this application it would appear to offer little strength as the tongue is relatively thin for its length, it will nit stand much leverage of the joint without glue / resin. Some form of bridal joint which is pegged would appear to offer a better solution.

To cut the joint, it would be very similar as Zededhed has highlighted apart from using a chisel to make the chamfers of the dovetail. To achieve accuracy a jig which consists of a piece of wood with the dovetail angle is cut and clamped in place. This is then used to guide the chisel (laying It in the angle provided by the jig) to refine the taper consistently and accurately on each side.
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By MarkDennehy
#1057118
Glue line would be running up the side of the piece (so the dovetaily bit would be from one 2x4). The more I think about dovetailing it thought, the less I think it needs to be dovetailed at all; it's the top of a leg joint going into a workbench, and the dovetail is slotting into the apron and gets pinned almost like a drawbored tenon joint with the apron as the tenon. If I didn't dovetail it and just left the edges square... well, it's a workbench, it doesn't need to be hugely fancy (he said having shown off a complicated plan for a joint - but there's a reason for the complex bit, the bench won't be moved regularly, but I will want to move it at least once in the next 2-3 years so it'll have to be takedown-able (even if I have to drill out a peg or two to take it down)).

The part that's been worrying me most is the long slot/housing part; cutting that with hand tools (not having a bandsaw myself, just a few ryobas) and not weakening the piece. I don't need to do it fast, this being a hobby for me rather than a job; but I'd like to not make a dog's breakfast of it.
By Jacob
#1057127
I'd start again and aim for a better design - unless there really is a purpose in that complexity, which I doubt.
99% of joinery and furniture is made with only a small repertoire of joints and your's isn't one of them!
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By MattRoberts
#1057147
Jacob wrote:I'd start again and aim for a better design - unless there really is a purpose in that complexity, which I doubt.
99% of joinery and furniture is made with only a small repertoire of joints and your's isn't one of them!

I agree - that 180mm long 20mm thick dovetailed tenon seems pretty pointless to me (since joints are supposed to be as strong as possible), and would be a nightmare to cut.

If you could reduce the height of that 180mm to whatever your max cut depth is, then it wouldn't actually be too hard.
By deema
#1057159
With an apron it sounds like a traditional English bench, good choice IMO. Aprons are normally screwed on, they can get covered in glue and other stuff or too many dog holes which necessitates either replacement or a clean up. Simply unscrewing makes life less of a chore.

Two M&T frames either side with stretchers that are tennoned with knock out wedges and a top that's either bolted or screwed on makes a sturdy easy to move bench. My work top is bolted down, it makes taking it off to run through a P/T easy every once in a while. When it gets a bit thin, I make a new one.

I may be out in a limb here, but a bench is a tool, you use it to make work you can proud of. The mire fancy / work you put into it the less likely I have personally found I use it properly......concerned with denting the top.....concerned with a saw mark, drill going too far........you at some point take stock and recognise one of two things depending on why you do wood work.

1. The bench does not get Oaul for by the client. They don't care how fancy it is or indeed how rough it looks. They want good quality work at an affordable price.

2. Your family and friends who benefit from your hobby value and love what you produce, few if any venture into the workshop, and fewer still who do know really what they are looking at. The door, window, box, chair or what ever is what gives them joy.

If the bench is flat, provides good clamping possibilities, stable, and at the right height in my book you've created a work of art. Love it enjoy it and produce something that others care about.
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By MarkDennehy
#1057184
It's where the leg meets the benchtop Jacob.
And yes, it's deeply unprofessional, no pro would ever use something so finicky, they'd lash a fire door to a pair of sawhorses and get on with it; but they've got to get some work done by day's end to pay the mortgage, whereas I'm doing this after day's end for fun and my mortgage's been paid by the stuff I was doing earlier in the day. Not disagreeing with you really; I just know my own head by now and this is how it learns new stuff - it makes a totally over the top fancypants start into things and gradually simplifies. And I'm okay with that, 'cos I'm having fun all the while.


(Besides which, if it actually works, it'd be neat. And if not, hell, pine burns pretty well and it's almost BBQ season... :D )
By Jacob
#1057186
Right!
What about just making a simple bench and then using that to make complicated (sculptural) things?
i think there are a lot of frustrated artists amongst the amateur woodwork fraternity. They hide it by making pointless but complicated things, obsessively polishing tools and similar.
They might be happier out of the closet!!
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By MarkDennehy
#1057189
It might be helpful to think of amateur woodworking like sex with your spouse Jacob.

No, bear with me a minute.

It's messy, it doesn't look pretty to outsiders, there's often a lot of strong language and sweating, some folks do it all by hand and some use power tools, it's usually done at home, it's definitely not done the way the pros do it, most people don't do an apprenticeship with a master craftsman to learn how to do it, it doesn't pay the mortgage and yet despite all that it's a ton of fun so you keep on doing it anyway and enjoy it immensely even when you make a total pig's ear of it.

Oh, and you don't really don't care if it's done efficiently or not, you just like doing it well while you're doing it. Even if it doesn't actually produce anything at the end that you can show off to your parents or neighbours. And if it takes all day, that's not a bad thing...



I was going to make a joke here about bench dog holes, but... it seemed too vulgar for Radio 4.