Joining two planks?

[joiner_sim]

:?: I have seen some pieces on here where two contrasting timbers are used together, to form one piece of timber. Well, I'm sure I have, unless I've just imagined it. I'm going to make a small box soon (for jewellery or something like that). I want the four outside's two be either dovetailed or finger jointed. :arrow: Anyway, to get two the point. I want to glue two different timbers together to create the sides. The picture below better says what I'm thinking of doing. Now is this possible or are there any other different approaches to this that you could suggest? (I intend to cut the "sway" on both timber first and then glue up afterward?)

 

[joiner_sim]

Also, how would I joint these two timbers together, as I don't think my dowelling jig would work here.

Just butt joint?

 

[OPJ]

I reckon you should be able to biscuit joint the two pieces together for alignment, provided you cut them fairly carefully and don't put too many in there. Best way to cut the curves accurately would probably be to make a pair of MDF templates, clean them up and match them for a perfect fit, then stick them on with double-sided tape and rout away. :wink:

Interesting idea, what timbers do you plan on using?

 

[wizer]

Just one template is needed, rout both timbers the flip one round to match. Biscuits should work as long as the cruves aren't too tight.

 

[joiner_sim]

I love this forum! Silly me was going to bandsaw the "sway"! Template & Router it is! I can borrow the company biscuit jointer for this then. I wasn;t really sure about just the biscuit jointer as I thought I need it to be flat, but I suppose if the curves aren't too tight it should work.

I'm thinking of using something like sapele and ash..... Will have to see what I can pick up from work, it's only really a practice piece, but hopefully will turn out nice, haven't really got that far into the design yet.

 

[MikeG.]

No template needed!!

Fasten one board above the other, overlapping in the area of the cut line only. You could pin, or hot glue, screw.......anything really. Pack out the free under-edge of the top board so that the pair will sit flat, then jigsaw, bandsaw or scroll-cut your curve through the overlapping section. You will only be inaccurate by half the kerf, which will amount to nothing at all with gentle curves and a thin blade.

Mike

 

[OPJ]

You could even approach Mike's method with a router and bearing-guided trimming cutter, if you clean up one of the halves first. :wink: Double-sided tape always works well for me in situations like this.

 

[joiner_sim]

What about the movement of the two different timbers? Will they pull apart in the future?

I may not be able to use biscuits, as the timber thickness I might use could be quite thin.... about 12mm?

 

[OPJ]

Have you got a router table? If you used a thinner bearing-guided slot cutter you could rout some longer grooves in each piece and then thickness (?) or cut (bandsaw) some thin 'splines' to fit.

 

[joiner_sim]

No router table, but I'll think about getting one. I know what you mean though OPJ about the 'splines' I have used this method of gluing up before. It's either that or thicken up the timber. Also been thinking... I want it to all look joined up as one piece.... This will probably mean no dovetails and more of a mitre joint instead.

 

[TheTiddles]

If you only want the effect on the surface maybe veneer is a consideration, it's much easier to allign perfectly as you can cut it with a knife so not removing any material, other than that the best idea is to place one over the other as suggested, two templates is possible too, though Wizers single template idea assumes it is perfectly symetrical in the horizontal axis which is all but impossible without a CNC cut template, maybe he's too distracted with buying new kit to worry about the practicalities of actually making something! :lol:

Aidan

 

[joiner_sim]

Right, I've been thinking about the two timber's I would want to use. Did a bit of googling for timber samples and matching them up. I have came up with these three timbers. American red oak, brazillian cedar & sapele. Here's my samples. Personally I like the oak & sapele, as it's colour is similar, but would one of the other two be better? Brazillian cedar goes much lighter and paler once sanded.

^Sapele & Oak

^Cedar & Sapele

^ Cedar & Oak

Any suggestions would be very much appreciated.

 

[TheTiddles]

Cedar is very soft, especially comparred to the other woods you are looking at, when you work them you might find you are prefferentially removing the soft one making hollows in the workpiece, maybe something harder?

Aidan

 

[joiner_sim]

I think it'll be the sapele and oak then, i forgot about the cedar being so soft. I'm trying to look at using timbers that we have in work, obviously for cost wise :lol: its free if we got it there!

Just thinking about the timber available, we also have some hemlock. So tried oak & hemlock, baring in mind the hemlock is usually a grey colour compared to what is shown in this picture (but the grain is right).

I did try the hemlock with the sapele but the grains were not similar and has got me thinking is hemlock and oak a better alternative to sapele & oak?

 

[dunbarhamlin]

IIRC first part shaped and then used as a 'template' with a bearing half diameter of cutter to cut the scrap template used on the second half - cut with router cutter and bearing of same size (and same size as original bearing) - this provides a perfect match as the necessary distortion is put into the scrap template.

 

[OPJ]

I like the subtle contrast between the sapele and oak in the first image. I reckon the others are a bit too different.

Back on to the template...

If you rough out the shapes on the bandsaw and then butt them together, edge-to-edge (leaving plenty of waste towards the square edges), all you need is one template stuck on top and then run cutter through both pieces at the same time.

You might be able to to this with a bearing-guided cutter or, you could just use a guide bush (follower). :wink:

 

[wizer]

What about maple and walnut?

 

[joiner_sim]

I'd love to use maple and walnut, but don't have any way of getting some, well without it costing.

 

[Mr Ed]

If you cut 2 at the same time, with board A on the top and board B on the bottom you will end up with two sets, one the opposite of the other, by mating the left board of A with the right board of B, and so on...

Personally I would just butt joint this - there is no need for biscuits in my opinion. I think you can make perfectly good glue ups for table tops etc without them and concentrate on accurate edge jointing and careful clamping.

Cheers, Ed.

 

[MikeG.]

My two-pen'orth on the timber mix is that you have two of my least favourite timbers in your selection.......American Red Oak and Sapele. I am just biased against the red oak without great cause.....although it is so porous you can suck air through it along the grain (which makes it unsuitable for anything that will ever see any weather). Maybe it is is just boring in comparison to white oak or the European oaks. Sapele reminds of those nasty 1970's flat panelled hollow internal doors.

Instead of maple, use the European equivalent which is sycamore. I believe this is quite cheap.

Mike