Joining Mahogany

[johnuk]

This isn't strictly guitar related, but it's close enough...

I wanted to use some wide Mahogany boards for something but the widest the planks come is 6". After machine planing they end up at about 145mm wide and 18mm thick. I would be using roughly 800mm lengths of this timber to form boards around 435mm wide; so about three of the planks would be lying side by side.

I understand how to glue using Titeboard but I am kind of stuck on how I should go about joining the piece together.

Sash clamping is the most obvious option. But I may need to produce a number of these boards within a certain time frame and buying tens and tens of sash clamps that can open over 400mm is going to cost quite a lot in itself. Also, this method is far too time consuming and labour intensive for the number of boards that will need clamping.

Can anyone think of an ingenious method for clamping, or squeezing the boards, on mass?

I thought that one idea might be to produce something similar to a mitre box with a removable side. It could even be put together from metal I guess. Some sort of grill would support the boards to keep them level; this would stop them gluing themselves to the jig. I also thought it would help if another system applies pressure to their other sides to keep them level with each other and ensure none have caught on something and stuck slightly out of alignment. The box would have an internal width of something just under 435mm so when the side was closed it would squeeze the pieces together.

That's just an idea anyway. Is there anything already available for doing this kind of thing? I know it is, or at least was, quite common place for carpenters who were laying floors from such planks to do something similar. Surely out of all those carpenters, one must have already thought of a solution to it other than sash clamps?

Ideally the clamp would be able to hold two or three boards at a time. I figured I could achieve that by using machined spacers between each board, since, by the time they're glued, they're not going to fit back thru the automatic plane.

Thanks for any help with this!

John

[daveq]

If I understand your problem (if), I think I may be able to help. Depening on the length of the boards, you can build a clamping system similar to what I use for bookmatching maple tops. Use a 4x8 (or what ever size works) piece of mdf and screw two straight edged boards along the sides. Make some wedges to apply the pressure (make pairs of wedges to work together if you know what I mean). Place the boards on the mdf (with wax paper in between) and tap the wedges to apply the pressure. I would assume that you are going to put in dowels or biscuits to help join the boards, right? I also put lots of weight on top of the boards (bags of pea stone) to help prevent them from warping.

Let me know if it's hard to picture what I'm talking about. I think I can find a web link to a pic of something similar to what I described.

[johnuk]

If I understand your problem (if), I think I may be able to help. Depening on the length of the boards, you can build a clamping system similar to what I use for bookmatching maple tops. Use a 4x8 (or what ever size works) piece of mdf and screw two straight edged boards along the sides. Make some wedges to apply the pressure (make pairs of wedges to work together if you know what I mean). Place the boards on the mdf (with wax paper in between) and tap the wedges to apply the pressure. I would assume that you are going to put in dowels or biscuits to help join the boards, right? I also put lots of weight on top of the boards (bags of pea stone) to help prevent them from warping.

Let me know if it's hard to picture what I'm talking about. I think I can find a web link to a pic of something similar to what I described.

That's sounds like such an easier idea! I fully understand what you're describing.

The main problem was the rate I could join the boards, so the simplicity of the wedge idea is an ultimate extra.

I really appreciate your help!

John