Steaming timber

[Michael Rogers]

I am still in search of the ideal tiller for my Trouper 12. It has to have two rather precisely placed bends in it, thankfully both in the same plane. I have decided to try laminating, and this is a request for some experienced advice.

I will be using thin laths, probably of pine/spruce/fir, a metre long, about 3-4mm thick and about 35mm wide. I have the wherewithal to make a steam chamber - a steam wallpaper remover, tubing, a suitable length of 6 in diameter pipe. It presumably helps to bundle the laths in the steam chamber with spacers so that the steam gets to all sides. I think (sounding more confident than I feel?) that I can devise a jig to shape the steamed timber round the necessary curves (I may have to increase my clamp supply).

I would be grateful for general advice about whether I seem to be going about this the right way: and specific advice on the following -

      1) for how long should I steam the wood (I really have no idea)?

      2) I plan to glue up with Collano Semparoc, which I believe can cope with high moisture content in
          the wood. Is that correct? If so, can I bend and glue straight out of the steamer? If not, how do
          I go about it?

Michael Rogers

[markbatey]

Are you sure you need to steam thin strips of wood? I've just done a laminated floor on a restoration project that I'm helping out with, probably a little bigger than your tiller. We used oak at about 3mm and it bent quite happily dry and unsteamed. Maybe you could try a dry run - build the jig first, then see if a sample strip can be persuaded to follow the curves. If it's reluctant, try thinner strips?

Mark

[Michael Rogers]

You may be right, Mark. I tried with mahogany 'structural veneer', about 2.5 mm thick (another project), and it didn't want to know - cracked at the (relatively) slightest attempt to bend it. It's probably a matter of 'know your woods and what they can/can't do' - and I don't!

The other practical issue is getting hold of wood which might serve, and in small quantities, to experiment with; especially cut thin enough. Places like Robbins want to sell you enough to re-plank a tea clipper, and charge the earth. Any suggestions, anyone?

Michael

[Colin Morley]

Hi Michael,

If in doubt look in Google or Youtube. See these:
http://www.ultimatehandyman.co.uk/how-to/woodworking/bending-wood
http://www.instructables.com/id/How-to-make-a-steambox-for-bending-wood
https://www.youtube.com/watch?v=L4U7axO7tXc

Best of luck

[Julian Swindell]

If you can call into Robbins, they have stacks of off cuts inside the door, and you should be able to find enough bits to make a tiller. As some others have said, I would have thought you could bend the strips cold. I have made some fierce curves around canoe stems without much trouble, using walnut (as it turned out, I thought it was mahogany) and "white wood" from the local builders merchants. Oak I tried once and that did crack. I have never steamed, but I think the problem is gluing the wet wood. Most traditional steaming is solid wood which is to be riveted into place.

Have you tried just heating the strips with a heat gun whist you bend them? I have done that for gunwales on a dinghy. You have to be careful not to burn the wood/yourself/the entire building, but apart from that it worked OK. The benefit is that the wood stays dry, and I glued it with epoxy.

[Michael Rogers]

Thanks all. It's as if everyone is getting stuck in to my problem, which is a good feeling.

Colin, I'll follow up those links.

Julian, your mention of Robbins is actually apposite and rather amusing. I've bought from them before at distance when I lived oop north: they advised on the phone or by email, and shipping was always pricey (their packaging was excellent). Mentioning them myself when starting this thread, I SUDDENLY realised that, for goodness sake, I've moved and Robbins are only about 15 miles down the road from here, not 120 miles away!! So I can easily do what you suggest, and pay their off-cuts a visit.

[Peter Taylor]

For those not near Robbins a possible alternative is Howells teak in Poole.  Again it's best to visit and look through their offcuts bins (although if you phone and say what you need they would probably try to find something suitable). Although mainly teak, they do do other hardwoods and also good quality marine ply in smaller sheets than you are likely to find at Robbins.

Peter