Seeking advice . . . or wasting my time??

[TTIT]

Looking for some help. I'm trying to straighten the side rails of an old wool-classing table to convert it into a dining table for a friend. Too many years of being overloaded with junk or bent from the word go, one rail had a sag of about 25mm, the other about 15mm. I gave it several months upside down and weighted with a pile of bricks which took out about 10mm of sag but the last 15mm or so is being stubborn. Today I tried clamping some 5x65mm steel bar to one side after pushing the sag about 12mm past straight - sprung back to about 5mm of sag once I took the weight off. Tried again with two pieces of the steel bar (equal to 10x65mm) and it still sprung back to about 2mm past straight. I don't think the recipient really wants that much steel under the table but can't think of any other way to hold it straight enough to support a sheet of glass. As near as I can tell the rails are Ironbark which would have been milled in the Gilgandra area where the table originated. The pic shows the rig I have set up to push it past straight while I clamp stuff on. Any suggestions to straighten the rails or am I kidding myself????

487460

[aldav]

I've seen much larger steel sections straightened with the use of pressure, as you've applied, and then peening to impart the shape that it's been bent to. Don't know whether this is possible for you to do, but I suspect that's the only hope you have a having a win.

[Bushmiller]

Vern

This may require leap of faith, but I would go along with what you have already done but soak the timber in water first. This has a similar (but probably not identical) effect to steam bending and will plasticise the wood. As with steam bending, some allowance has to be made for spring back and that may be difficult to judge. Ironbark may not be the best timber for this, but we are not trying to make a bentwood chair.

The question I can't answer is whether there was a degree of spring growth right from the start or whether it is a result of many years of overloading as you suggest.

While I know of somebody who used to do this, I have not done it myself and I don't know how long the timber should be immersed. I would think at least a week and more if possible. If it is Ironbark you won't have to weight it down in the water as I am sure you know. A piece of large dimension PVC pipe may be big enough with one end capped for the water bath. Much will also depend on the time frame you have available. I see that you have already been wrestling with the problem for some months so a little longer may not be an issue.

There is one other potential issue if you pursue this technique and it is that being a retired wool classing table it may be well soaked with lanolin and want to resist soaking with water.

Please excuse me now while I wipe the drool from my face as I could not help but notice all that beautiful timber behind your "press." It was difficult to concentrate on the task at hand.

:)

Regards
Paul

[Tonyz]

stand it in front of my wife's car as she tries to park.

[aldav]

Ha ha, I totally misinterpreted your initial question, didn't I! :B

[TTIT]

Vern

This may require leap of faith, but I would go along with what you have already done but soak the timber in water first. This has a similar (but probably not identical) effect to steam bending and will plasticise the wood. As with steam bending, some allowance has to be made for spring back and that may be difficult to judge. Ironbark may not be the best timber for this, but we are not trying to make a bentwood chair.

The question I can't answer is whether there was a degree of spring growth right from the start or whether it is a result of many years of overloading as you suggest.

While I know of somebody who used to do this, I have not done it myself and I don't know how long the timber should be immersed. I would think at least a week and more if possible. If it is Ironbark you won't have to weight it down in the water as I am sure you know. A piece of large dimension PVC pipe may be big enough with one end capped for the water bath. Much will also depend on the time frame you have available. I see that you have already been wrestling with the problem for some months so a little longer may not be an issue.

There is one other potential issue if you pursue this technique and it is that being a retired wool classing table it may be well soaked with lanolin and want to resist soaking with water.

Please excuse me now while I wipe the drool from my face as I could not help but notice all that beautiful timber behind your "press." It was difficult to concentrate on the task at hand.

:)

Regards
Paul
Thanks Paul. I had thought about wetting/steaming but at 8' long and 6" wide, I don't have anything available to soak it in as such. I have considered giving it a good wetting and wrapping it in builders plastic in the sun - if that doesn't create some severe humidity out here there's something wrong . . . but I don't know if it will have any affect on Ironbark 1.5" thick. Might be my only option at this point.

[TTIT]

Ha ha, I totally misinterpreted your initial question, didn't I! :B
No harm done . . . I guessed that you thought I was trying to get the steel to match the timber instead of the other way around :wink:

[havabeer69]

Cant just rip/joint the bow out?

[TTIT]

Cant just rip/joint the bow out?
I hadn't considered that and I suspect it might work but a join along the sides would destroy the rural look . . . I think :shrug:. Might run it past the owner as an option :think:

[russ57]

If it was me...
Make up a trough with any old boards, line with plastic and soak. Support the ends, With a a weight on the middle to overbend.

[malb]

I would hate to be a misery guts, but if the table was a wool classing table for any appreciable time, the timber will be fairly heavily impregnated with lanolin, and fairly impervious to water or steam, that's why sheep's wool has a high lanolin content, to keep moisture out and provide additional insulation for the animal. I doubt that steaming or soaking will do a lot to allow the material to be straightened and stay straight long term.

[TTIT]

I would hate to be a misery guts, but if the table was a wool classing table for any appreciable time, the timber will be fairly heavily impregnated with lanolin, and fairly impervious to water or steam, that's why sheep's wool has a high lanolin content, to keep moisture out and provide additional insulation for the animal. I doubt that steaming or soaking will do a lot to allow the material to be straightened and stay straight long term.
Unfortunately the table has spent some years outdoors and most of the lanolin has weathered off the outside and it doesn't look like it ever reached the inside of the rails. I've spoken to the owner and they aren't keen on the rip/joint method so we are going to give it a soak and see what happens :shrug: I too am dubious about how far water will soak in and how much/little effect it will have but I have to try something!

[auscab]

Ive been wondering how I could straighten some long Elm Boards that have a bend in them .

I thought placing them over a big fire or hot coals may do it . But had no idea how I'd handle them

Then I saw this film the other day and in it the guy shapes a wet canoe over a fire . I liked the set up with the branches he had set up in the ground to hold the canoe above the fire . It made me realize there is a way with My large Elm boards . A way to hold them but also place the board and apply pressure when its hot doing something similar near the fire .

Don't know if Ill try it yet . I may cut them up for shorter seat blanks for some chairs Id like to do .
You can bend wood if you get it hot enough with just the small amount of moisture that remains in it after its dry . Not ideal possibly but it does work .

Here is the link to the film . Its on SBS on demand . Living Among Trees.

The Hot canoe starts at the 9.20 minute mark . The whole thing is good though . Specially the workshop at the start.

Living Among Trees - A World Of Calm, Season 1 Episode 5 | SBS On Demand (https://www.sbs.com.au/ondemand/video/1833524291887/a-world-of-calm-s1-ep5-living-among-trees)