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IanG
11-Dec-2012, 12:54
Last weekend I bought a whole plate camera from another member of this forum to restore, so priced as such (no complaints). However the front lens standar has a stron bow in it and I will need to straighten. This is what it's like -

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I'll remove the bellows but any suggestions on how to straighten this, the curve is quite pronounced, until it's straightened I won't be able to add a lens board easily. I've a slight warp in a back on another camera so plan to do them both at the same time.

After that I've got to graft in a new piece of mahogonay where the front rail has been repaired in the past but this should be less problematic. I've plenty of vintage bits of wood that will match.

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Any advice would be appreciated.

Ian

vinny
11-Dec-2012, 13:06
eessh. run it through the planer!

cosmicexplosion
11-Dec-2012, 13:09
One thing you can try is putting two chocks of wood under each corner and clamping down the middle. Then apply heat from a bar heater or heat gun if you have or mate has.
Soaking the con curved side on water will help.
It may also require setting for a few days and a bit of encouragement from aforementioned techniques.

When done give a good oil or varnish
As it could be a no good bita timba
That's prone to warp. Keeping moister out is top priority.
If it fails you need to make a new bit.
A furniture maker will help you.

Richard Wasserman
11-Dec-2012, 13:12
Any chance you can make a new replacement standard? It might be easier than trying to straighten the warp (I don't know how you would do that) and do the other repair.

Drew Wiley
11-Dec-2012, 13:13
It would be easier just to make the whole piece from scratch. Otherwise you can remove it
and try to weight press it for maybe six months, but that's no guarantee it won't warp in
the same manner again.

E. von Hoegh
11-Dec-2012, 13:31
Make a curved lensboard.

Drew Wiley
11-Dec-2012, 13:34
Photograph Einstein's curved universe.

Steven Tribe
11-Dec-2012, 14:18
I personally think that the bow is so great that making a replacement is necessary. This must be one sick piece of wood - grainwise.

Otherwise you could make up a temporary steaming container (like steaming vegitables in the kitchen) and then clamp it flat. My experience is mostly with ash which is a dream to work with. Remove the lacquer before steaming.
Don't worry about wetness, the item has to be clamped before going in the oven to dry.
It is the initial drying of fresh timber which has to be done carefully and slowly.

E. von Hoegh
11-Dec-2012, 14:22
You need to use an anamorphic lens on that camera.

E. von Hoegh
11-Dec-2012, 14:22
Photograph Einstein's curved universe.

Wow. What kind of shutter would you use?

Drew Wiley
11-Dec-2012, 14:52
You use a time-travel shutter.

Kirk Gittings
11-Dec-2012, 14:56
That telephone booth might strain your back on those long hikes......

E. von Hoegh
11-Dec-2012, 15:18
That telephone booth might strain your back on those long hikes......

It's OK, I hear they have cell-Tardises these days.

Brian C. Miller
11-Dec-2012, 15:59
I recommend the weight press. When the Pittock mansion (http://www.pittockmansion.org/) was restored, a couple of the bedrooms had warped oak plank flooring because the windows had broken, and rain water had come through. The people thought that all of the flooring would have to be torn up and replaced. One of the original builders was still alive, and he told them just to set barrels on the boards, fill barrels with water in the fall, and then in the spring the planks would be flat. It worked like a charm.

Here's the problem with soaking that wood: the glue might be hide glue, which is water soluble. Hide glue is a great glue, and has been used probably before the Egyptians built the pyramids (it was in use at that time), and one of its features is that it is water soluble. This means that something put together with hide glue can be taken apart later, no muss and no fuss.

Jim C.
11-Dec-2012, 16:00
Seems like the front standard is separating, it might be easier to reproduce that warped part out of your
old wood stash, other wise like some others have said it may take months for that to straighten out
and even then there's no guarantee that the bow won't come back.

IanG
11-Dec-2012, 16:02
You use a time-travel shutter.

I've some rather nice shutters sitting waiting, one of which I've not found on the Internet but has a piston pneumatic release T, B & I (1/15 - 1/900 and works a treat, so some good time-travel :D

My box of shutters has spilled over rapidly recently into a second box, all fully restored, all-sorts but very practical and far more accurate than Packards (just remembered my Packards in the oven) :)



I personally think that the bow is so great that making a replacement is necessary. This must be one sick piece of wood - grainwise.

Otherwise you could make up a temporary steaming container (like steaming vegitables in the kitchen) and then clamp it flat. My experience is mostly with ash which is a dream to work with. Remove the lacquer before steaming.
Don't worry about wetness, the item has to be clamped before going in the oven to dry.
It is the initial drying of fresh timber which has to be done carefully and slowly.

Actually the whole piece is three bits of wood, the two parts that would hold the lens board in place screw to the main panel, so maybe there's a chance of possibly straightening. Removing the lacquer, which is french polish isn't a problem, and I'll be re-french polishing the rest of the camera anyway.

I'll strip it and steam it, then clamp it and see how it dries in the oven, if I get most of the bow out I could work with it easily.

It would be a shame to make a new piece as it's quite large and has character in it's polished wood grain (on the ends) that would be impossible to emulate, so I'm prepared to have a few goes at getting it usable.

At the moment this particular camera is at the back of the queue for my personal restoration, there's 3 LF SLR's and a Half plate camera need finishing plus a myriad of jobs/work on other peoples cameras, but this looks so nice . . . . . . . . . . . . I'd like it to look half way at least.

Ian

Steven Tribe
11-Dec-2012, 16:03
I think some contributors here have a very warped sense of humour!

E. von Hoegh
11-Dec-2012, 16:14
I think some contributors here have a very warped sense of humour!

I agree, you'd think large format photographers would know about gravitas and decorum. After all, we're representatives of a dying art form. Oh well...

Jim Jones
11-Dec-2012, 16:44
I agree, you'd think large format photographers would know about gravitas and decorum. After all, we're representatives of a dying art form. Oh well...

Gravitas and Decorum are straitjackets for the creative mind. Consider Richard Feynman. Or, for those too grave and decorous for physics, how about Elliott Erwitt?

Alan Curtis
11-Dec-2012, 16:46
I would contact Richard Ritter, from this forum. He can most likely fix it or make a replacement.

ic-racer
11-Dec-2012, 17:13
I'd approach this like the common bowed up bridge on a steel-string acoustic guitar. So, first I'd separate those two pieces. Then use steam to straighten them out and re-glue them back together under pressure. The glue joint will keep them straight if you do it right.

sully75
11-Dec-2012, 17:16
I've never tried this, but I think you can use a microwave as a steamer. I saw a video of someone doing that on youtube the other day. If you steamed it, and then clamped it to a flat board (perhaps with a milimeter of shim on either side to give it a little extra curve for "springback") you might have a pretty good shot at straightening it.

Also, if you steam the glue seperating the parts, you might end up with three less crooked parts. Straighten each one and then glue them back together flat. You might have some success that way.

Good luck

Paul

Drew Wiley
11-Dec-2012, 17:27
Steaming has its risks, besides glue ... you might raise serious tannin stains unless the wood was ammonia-fumed long ago (don't try that at home, folks).

Tim Meisburger
11-Dec-2012, 17:41
Remove the finish, steam it, clamp it overbent slightly (something like a penny under each corner with the clamp in the center). I would not put it in the oven. Just let it sit clamped for a week or so while you work on other parts of the camera. Should be fine.

wombat2go
11-Dec-2012, 21:57
Hi Ian,
I am no woodworker but I would say it was due to incorrect craftsmanship at the build time.
Gluing 2 different thicknesses of different woods with a strong continuous glue joint (I presume hide glue ?) could hardly be expected not to warp, and maybe this started early in the life of the camera. From the photo the thick piece on the bellows side has shrunk slightly more than the front piece as it all dried.
I have an interesting book " "The New Science of strong materials" by J.E Gordon writing about his experiences in design of wooden aircraft and boats up to WW2
Quote " Wood is not a material which suffers fools gladly.."
According to him, Casein glues, ancient but re-introduced in 1930's were better at gluing wood because they were weaker when damp and could shear to reduce stresses somewhat.

I just looked at some old 1920's furniture here, they knew where to glue and where to leave different pieces unglued and free to move.
The results are "creaky" but less warping.

IanG
12-Dec-2012, 02:20
I would contact Richard Ritter, from this forum. He can most likely fix it or make a replacement.

If I can't fix this piece I'll either make a new one myself or failing that I'd use a local cabinet maker. I prefer to keep everything close to home and the costs to a minimum.

I'd already decided to strip the shellac and paint and steam the part (post #16 of this thread) and that seems to be the general consensus of other posters opinions.

Steven Tribe's comments about the wood grain made me look closely at the piece and unusually it's one solid bit of wood, the two guides for the lens board are inconsequential, on other vintage wood/brass British cameras I own the part is composite from a fiew parts glued and screwed together.. The warp on this follows the grain, it may have been caused buy someone using water to remove adhesive where the bellows attach as there's evidence of some sort of repair or re-glueing.

Ian

IanG
12-Dec-2012, 13:22
I hadn't intended to start on this camera so quickly but I've now straightend the part. I guess starting this thread and getting so many replies made it a challenge :D

Surpringly it didn't need steaming, I had to soak it in hot water to remove the residual glue from the bellows and soften the glue used to hold the two lens board guides, I'd already removed the screws. I then rubbed it down to remove the french polish/shellac varnish and black paint on the back. The small parts aren't thick and had bent with the warp but returned to flat once removed.

The main piece was warmed in the oven (after a good soaking) at about 75C and resoaked in hot water then pressed gently in a reverse curve to the warp, this was enough to straighten the panel after a few cycles, and it stayed flat when I dried it in the oven. I've stabilised the wood so it shouldn't warp again and looking at the end of the bellows I removed it confirms that the warping probably took place because of a repair as I'd thought. The hole in the centre of the panel is cut accross the wood gain and rough finished and the area highly was porous so any water used to remove glue would have been drawn in and it's like sponge when wet.

So the piece is re-assembled and finished.

Ian

Steven Tribe
12-Dec-2012, 14:04
Well done!
My wife is a willow work artisan (sounds better than basket maker!) and we have a very large zink container for softening the basic material. I have tried to convince her to try steam treatment rather than cold water (better when its -10 deg. C outside), but with no success.

Steve Smith
12-Dec-2012, 16:31
The traditionalists won't like my proposed solution, but if this was mine, I would look into machining some of the wood away and inserting a machined aluminium (not aluminum) piece to hold it straight. Hopefully it could be inserted from the rear and hidden with a veneer of matching wood.

Might be easier to just make a new one though.

EDIT: However. If I bothered to read to the end of this thread I would have realised that neither method was now necessary!


Steve.

Jac@stafford.net
6-Jan-2013, 15:05
A minor tip - remove the wood front and to separate the glued parts, microwave for about a minute. It will all pull apart with no effort. Then decide whether you wish to remake or straighten via steaming and flattening.