the best non metal material for large format lens boards

[spoolman]

I have a number of 4x5 and 5x7 cameras that I am currently restoring to operation and I will be needing new lens boards for them (5 in all, various manufacturers). What would be the best non metal material (wood) for the job. I'm excluding metal at this point in the restoration as I find wood easier to work with and I have the tools to work with wood.

Doug

 

[RobC]

lens boards are quite thin. Any made of wood would easily warp or flex or crack. I guess some much older cameras may use thicker ones where wood may work.
If not metal then a rigid plastic or carbon fibre.

 

[frank]

A layered plywood (model) board. The perpendicularly laid plies prevent warping.

 

[RobC]

A layered plywood model board. The perpendicular laid plus prevent warping.

well yes but it needs to be thick enough otherwise it will still flex. It really depends on what thickness the camera fitting requires.

 

[removed account4]

basswood, or masonite !

 

[mdarnton]

I make my boards out of birch plywood from The Art Store (Dick Blick). One easy way is to use the right thickness for the front part of the board, say 3mm or whatever for some of my cameras, then cut a smaller piece of the same and glue it to the first, to create the light lock part. That works well for standard 4x4" boards. For my 5x7 and 8x10, though the same approach would work, I go for doing it the easy way by using only one piece of thicker birch plywood as needed for the particular camera and backing it with adhesive felt strips to create a light trap. I like this better and it's a lot easier. It may seem crude, but it works great. In either case, I black the resulting boards with india ink, then sometimes finish with shellac.

If you wanted to be fancy, you could use thicker plywood and machine the light locks. I have the tools and skills, but not the time for that. In either case, I prefer birch plywood because it's dimensionally stable, very easy to get and to work, and strong. Birch plywood is special stuff--not like from the lumber yard--made of thinner plies and harder wood.

 

[frank]

This plywood is available in various thicknesses, including a suitable one for this application.

 

[shutterfinger]

Another vote for Birch Plywood, Baltic Birch the best. I get mine at http://www.michaels.com/ . I use 1/4 inch thick material which is fine for most applications. Vintage boards are layered Mahogany or Rosewood.

 

[AgX]

[A layered plywood model board], well yes but it needs to be thick enough otherwise it will still flex. It really depends on what thickness the camera fitting requires.

Or one mills down just the critical edges to fit.

 

[Vaughn]

I have made a couple drymounting a piece of 8-ply white rag to a 4-ply black mtboard.

Not a vote for the best -- but it works fine.

 

[frank]

I have to confess that in my excitement/curiosity to try a new lens that I didn't yet have a proper lens board for, I have sometimes made a temporary lens board out of corrugated box cardboard.

 

[Roger Thoms]

For quick and dirty I use plywood. Baltic Birch if certainly nice but I have used 1/2" CDX that I planed down to 3/8" in a pinch. Not hard to find a section that is free of knots and voids. For nicer boards I like to try and match the wood to the same species as used in the construction of the camera and do a three piece board with tongue and groove joints. I bought a blade for my table saw that has a flat tooth grind and a 1/8" kerf that's nice for forming the tongue and groove joints. You could certainly use a router table and the appropriate bits.

Roger

 

[Jim Jones]

lens boards are quite thin. Any made of wood would easily warp or flex or crack. I guess some much older cameras may use thicker ones where wood may work.
If not metal then a rigid plastic or carbon fibre.

Lens boards for many newer cameras are indeed made from thin metal. However, for a hundred years many were made from thicker material, 1/4 inch or more. These can be made from MDF or, as others noted, plywood. The rabbet around the edges can be made on a table saw. although a router mounted on its table does a neater job. Also, these boards can be made from two hardboard or plywood pieces of appropriate size and bonded together. This eliminates milling the rabbet. The smaller piece serves only as a light trap, and can also be made of felt, foamcore, or many other materials.

 

[shutterfinger]

I have also made boards from black ABS plastic and black acrylic and plywood is the easiest to work with. ABS and acrylic are available in sheets of different thickness at plastic supply stores.

 

[RobC]

Lens boards for many newer cameras are indeed made from thin metal. However, for a hundred years many were made from thicker material, 1/4 inch or more. These can be made from MDF or, as others noted, plywood. The rabbet around the edges can be made on a table saw. although a router mounted on its table does a neater job. Also, these boards can be made from two hardboard or plywood pieces of appropriate size and bonded together. This eliminates milling the rabbet. The smaller piece serves only as a light trap, and can also be made of felt, foamcore, or many other materials.

Thanks for clarifying that.

 

[wildbill]

baltic birch plywood or phenolic like the wehman lens boards.

 

[John Koehrer]

For quick and dirty I use plywood. Baltic Birch if certainly nice but I have used 1/2" CDX that I planed down to 3/8" in a pinch. Not hard to find a section that is free of knots and voids. For nicer boards I like to try and match the wood to the same species as used in the construction of the camera and do a three piece board with tongue and groove joints. I bought a blade for my table saw that has a flat tooth grind and a 1/8" kerf that's nice for forming the tongue and groove joints. You could certainly use a router table and the appropriate bits.

Roger

I uses a router table for tongue and groove joints they're the prettiest. Like others have said, anything flat & opaque works.
Too thick? gaffer tape holds it in place.

 

[StephenT]

I also use the birch plywood in addition to solid oak. The birch is much easier to machine, but the oak is rather pretty. They both stain well and I use Teak oil, hand rubbed, as the finish coat.

 

[Michael L.]

May I suggest oldfashioned printed circuit boards made of glass fiber (FR-4, reinforced with epoxy resin)?
Leaving the copper layer on one side makes the board opaque to light; the copper on the other side can easily be removed and the naked fiberglass painted in an appropriate colour. These boards are available in many thicknesses/gauges and have very high flexural strength.
I have made several lens boards for my enlargers from this material.