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Bruce McCrory
22-Jan-2004, 19:09
I am looking to Deardorff to be my first LF camera. Since it is wood and obviously second-hand, I tried to research as much as I could of repairs and maintenance. A few things struck discord in my experiences with wood. Caveat; this is not experience with cameras but the same principles apply.

Design/Construction.

The table is of scarfed end-grain glue joints (X-configuration). The idea is probably to balance wood longitudinal expansion in all directions of the horizontal plane. I notice that wood Canhams use the same configuration. Seasonal movement is the greatest in this direction. This concept is fine, if the grain is straight, from the same source piece, abutting, and matched faces.

Unfortunately, the weakest glue joint is end-grain butt joints. The scarf is better but still a butt joint. A better configuration would be lapped face and quarter grain attachment; finger joints, tongue-and-groove being two examples. I understand the tables can start to separate at the joints. I will be very critical of my camera's table.

From Ken Hough's web site, I find that all Deardorffs were built from mahogany (Swietenia, "new-world" presumed). For nothing more than by name, this wood is difficult to distinguish from its "copies", Luan (Philippine), and African Mahogany, neither of which have the desirable characteristics of spanish (new-world) mahogany. What makes it good wood? Stability, low differential of grain movement, and durability. It is highly regarded for boat building. Of Western Hemisphere woods, mahogany, cherry, and black walnut (Juglans) have low differential of expansion. That is, swelling and contraction are fairly evenly distributed throughout the grain structure. That is why these species are common materials in wood cameras.

From my jaunts through the web, I found discussion of repair times for Deardorffs. It is a noble thought, but seasoned wood is pretty close to its ultimate stability and won't change direction in such small pieces as you find on cameras by sitting on the same shelf for months. It needs to find a different climate in order to get ugly. Wood pieces ripped from large blocks, and strippings, may spring and twist if from reaction wood and from spiral grain. As pretty as it is, I don't want environmentally grain-figured wood (as opposed to cut-figure) on my machine. Fresh cut and un-seasoned, or poorly seasoned wood pose major warp concerns at this scale. I've never seen "green" mahogany in a lumber store.

Glue joints will cure between the shop and my house while in the careful hands of the delivery people, thankyou.

Finish. Of the three common construction species, only cherry would give me concern when not protected. The others make good fence posts when heartwood is used. They all should be protected, and on all surfaces. No paint is better than half painted. Wood is a moisture sponge. It expands when wetted, by humidity or other, and you know the rest.... A finish seals the surface.

Wisner has the right idea regarding finish material. "Look to the sea for your answer, oh seeker." Spar varnish is designed for wood boats. It is flexible yet tough and resists moisture penetration. Eventually, weather and sun break down this shell, but I don't plan to park my camera in the yard. Maybe, trip and send it into a river, but that is not a plan either. I'll just take precautions.

Maintenance. While in college I had a great opportunity to work on the summer estate of a college benefactor. Wife had the prettiest little mahogany Century ski boat. The town's ancient boat-builder refurbished it after several years of improper maintenance. Every day, I wiped all exposed surfaces with oil. Could have been Pledge furniture finish, I've forgotten. (hbm)

matthew blais
22-Jan-2004, 20:25
Bruce, I'm not real sure what you're asking. But here's my thoughts on wood - it needs to breathe...plastic in any shape/name won't allow that. No varnish on anything I've ever built or restored (and yes, my projects are still around after 20 plus years). Tung oil is available in exterioir or interior for furniture. Either works. Follow with a good many coats of paste wax. Unless you plan on floating your dorff, don't spar with varnish.

If it's looking ugly, but not a good candidate for refinishing, try Howard's 'restore-a-finish" - great stuff. Then, paste wax and maintain with lemon pledge. Even good on the brass/metal (wax).

Sam Maloof, perhaps the world's most famous woodworker, lives nearby and I've had the good fortune of meeting him a few times, and he uses/suggests pledge to maintain wood.

If it needs a splice of wood to replace or repair, you might look at an old piece of furniture made of magogany (Duncan Phyphe, Empire style, whatever), get a piece out of that and shape. It should be seasoned enough, and you may have a better chance of matching wood, grain, finish, etc.

I used to build stuff out of the discarded oak pallets (when they made them of oak), plane it down and get some nice, strong, seasoned stock. I loved the junkyards/goodwills/used furniture stores, lots of usable stuff.

Good luck, sincerely, a wood "junkie"

Alex Hawley
22-Jan-2004, 20:42
Sounds like you've done a fair amount of technical research into this Bruce. That's good and your questions are excellent. I recently bought a Deardorff of about 1950 vintage and have spent a while examining its construction. I've also gained a fair amount of woodworking experience over the years. I have no inside knowledge as to the reasons behind Deardorff's methodology but here's my thoughts on your questions.

Table construction - I see its construction as being the best method for dimensional stablity in both directions. The reason is that no end grain is exposed. End grain has the highest ability to absorb moisture, hence inducing shrink or swell. The longitudinal grain I see in each of the four pieces appears as near identical as possible - in other words, its been matched. This, again, is the best method to prevent dimensional change.

Mahogony was long the favorite wood of Patternmakers for making highly precise patterns used for metal casting molds. The main reasons were because of its high dimensional stability, ease of working, and sufficiently hard to withstand reasonable abuse. Cherry and black walnut have similar properties as you say. However, cherry tends to burn very easily with high speed power tools. The price of walnut may have been the cut-off factor for its use. There are other woods which are more durable and tougher (teak, osage orange) but they are also extremely hard (translate SLOW) to work. Teak contains silica in its pores. We have untreated osage orange fence posts around here that have been in the ground for a hundred years and will still hold back a 3000 lb bull. But both woods dull tools a lot faster than they can be sharpened.

Glue joints - what you say about the butt joint is true but I believe it is sufficiently strong for this application and the long service life of 'Dorffs appears to substantiate this. No camera will survive a smash against the rocks without some damage. As the complexity of the joint goes up, so does the cost to produce it and so does the price the consumer pays. When making such a product, one has to balance all these factors together in the decisions made in its design.

Finish - this is the one that puzzles me a bit. I'm not sure why they chose, and stayed with lacquer all those years. Spar varnish would have been just as good. The tung oil and polyurethane finishes were not available nor proven until the later years of 'Dorff production but they would work too. Master craftsmen are reluctant to part with proven techniques that they like unless newer ones are proven undeniably better. Mine could use refinishing and I will probably use a tung oil and polyurethane combination, lest Leben strikes me dead for blashphemy.

I have no idea what causes the joint seperation on some 'Dorffs. Haven't seen it yet on mine. As far as techniques are concerned, there's always been a lot of "craft secrets" associated with building things from wood. Master craftsmen take great pride in what they build and certainly develop favored ways of doing things (I think I said that earlier). They insist that those that they train use the same methods because no others will do. But the important thing is the final product, not necessarily how it becomes the final product. The Deardorffs produced fine products for many years. So does Ron Wisner; he just hasn't been around for as many years yet. I'm sure his cameras are just as durable as the Dorffs were/are.

Hope you enjoy your 'Dorff whenever you get it.

David R Munson
22-Jan-2004, 21:18
Just a note on finish. I stripped my 8x10 'Dorff when I first got it and refinished it with pure Tung oil. Looks great, feels great, stands up well to being rained on (so it has demonstrated, anyway). Super-easy finish to deal with, too. I recommend it.

Tim Curry
23-Jan-2004, 06:03
-General reply-

It sounds like you will be happier with a metal camera. Try the Canham as they are superb in fit and finish.Or perhaps one of the new metal designs. Finish: Lacquer is used because of its ability to dry rapidly and build coats faster than spar varnish. It looks better much quicker, dries fast enough to not trap as much dust and gives a nice finish, albeit not very durable. Danish oil or Tung oil both act like watered down varnish and penetrate the wood as opposed to laying on the surface like lacquer, varnish or paint. Use it with wet sanding and it is the ultimate finish for wood in terms of depth and protection.

Glues: A lot of older cameras had "hide glue" as the adhesive, hence the problems. Best glues for wood now (and actually finish for that matter) are the boatbuilding epoxies which can penetrate the wood grain, set up in the joints and then encapsulate the wood fibers to make them impervious to everything but UV light. Flow modifiers are necessary to keep them in the joints until set, as are UV blockers for marine use.

Wood: Honduras Mahogony is an excellent, stable, durable wood for furniture and cameras. Trouble is, it is a tropically endangered species and those who use it drive SUV's, destroy the ozone and cause global warming. The Phillipine mahogany is good for cigar boxes (Luan) but not cameras, too soft. African Magogany (Meranti) is not a true mahogany, but is sold as such. It is ok, but not a true variant. Teak is good, as is Apitong.

Bruce Barlow
23-Jan-2004, 06:04
Call Richard Ritter. 802-365-7807. He restores and repairs Deardorffs and other wooden and non-wooden cameras for a living, and knows just about everything. Does good work, too.

Brian Ellis
23-Jan-2004, 08:07
It's a camera, not a piece of 18th century antique furniture. It's made to be taken outdoors, sometimes even in rain and snow. You carry it around in a backpack, the backpack isn't water proof or air tight. The camera also sits out in sometimes hot humid air or cold damp air on a tripod. Buy it, use it. Deardorffs are great cameras, the one I had was very well made. Assuming it's in good shape when you buy it you won't have to repair it unless you drop it or something.

Jim Galli
23-Jan-2004, 11:49
Hi Bruce. There's so much in this hobby / profession to get pedantic about that the camera doesn't need to be one of them. We are in a dream era where there are tons of very nice Deardorffs cast off by professionals who have moved on to other methods. It won't always be so. In 1946 you could buy J Duesenbergs on used car lots. No longer. The 'dorffs are just as classic but are in that period where supply and demand hasn't yet caught up to them. I believe they are the very best bargain in a camera to be found. Imminently useable and pretty to boot. I have 2 that cover 4X5 5X7 7X11 and 8X10. As far as your concerns I will add that I live in perhaps the most hostile environment to woods on earth. In Tonopah Nevada our average year round humidity is 8%. The 2 Deardorff's live in cases in the garage and will see temperature extremes in that same humidity of from 15 to 105 degress. I've seen other beautiful things made of wood twist into a pathetic knot in this desert environment but have to say the Deardorff's are surviving fine. No bed splits etc. so far. The 8X10 at near full extension made a trip into an icy river a year ago next month and the rear extension bed was cracked badly. I had to disassemble in the field to relieve enough of the stress to close things up and even transport. After complete disassembly and some glue and clamps it is performing as good as new and I'd be pressed to find where the damage even was. I took that opportunity to do some major cleaning and oiling with lemon oil and bees wax left over from the 1960's. BTW, when it fell in the river, even though it was twisted into a 22 1/2 degree angle it wasn't designed for, I used swings and tilts to straighten it up and finished the picture anyway. Now that's pedantic.

David E. Rose
23-Jan-2004, 13:45
The bed joints that you are concerned about are tounge and groove, not butt joints. This means that they have long grain to long grain gluing and therefore quite strong. You can see the T&G joint at the outside ends in the corners of the bed assembly. The bed is also somewhat reinforced by the side rails that house the front and rear extensions.

Donald Miller
23-Jan-2004, 22:23
I have three V8 (8X10) Deardorffs. I have refinished two of them. In both cases I sprayed laquer. On the older (70 year old NFS) camera the bed had developed separation. I took it apart and reglued it. It has held up very well. On my most recent camera I did have the rear rail cross tie glue joint fail and I took it apart and reglued it as well. I will probably strip and refinish that camera this winter. It doesn't appear that bad for a user camera but I just like the look of a newly refinished piece. I agree with what Jim said about the value of these cameras. The price will go up at some point.