|
|
|
-
Alternate materials that work like wood
This past Winter was the second full of failures trying to build a rather unique camera using wood. Wood is just not strong enough when as thin as I need it.
I am hopeing that net-wisdom here can point me to alternative materials that can be worked using wood-working tools (and meanwhile saving my pennies to have the parts machined in aluminum.)
The application is entirely of flat materials, 1/8th and 1/4" thick, with no joints (corners). Help?
tia
-
PVC, Polycarbonate and Nylon. All much stronger than wood in simular thickness and all workable with woodworking tools.
-
 Originally Posted by Dandy97
PVC, Polycarbonate and Nylon. All much stronger than wood in simular thickness and all workable with woodworking tools.
Those might be workable like wood, but they won't all be as rigid as wood.
Stability is a very important issue, rigidness is the key.
G
-
Use your woodworking tools to make molds for epoxy or plastic resins?
-
"Wood is just not strong enough when as thin as I need it."
Will you please list the properties necessary and engineering application which requires this material? Is the camera you are building a secret? Shear, axial load, tension, compression, bending? Spill the beans. tim
-
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
-
Have you thought of ply? Model makers shops sell it in various thicknesses. Or, you could laminate your own if you want something with an exotic wood finish... or laminate two sheets of wood with a kevlar, fiberglass or carbon fibre centre....
Bob.
-
In aircraft pattern building there is a material that is called Phenolic. I am not sure of the exact and proper name for this material. It can be machined to very precise tolerances, is rigid and strong. You may want to check into that. This material would not be susceptible to dimensional instability in the way that wood could be possibly.
Additionally, carbon fiber would be a good material. This composite is finding it's way into many aircraft fuselage assemblies because it is strong and it is light.
-
 Originally Posted by noseoil
"Wood is just not strong enough when as thin as I need it."
Will you please list the properties necessary and engineering application which requires this material? Is the camera you are building a secret? Shear, axial load, tension, compression, bending? Spill the beans. tim
First, please understand that I am not an engineer so I don't know what you are talking about; all I can give you is an idea.
4x5. The lens weighs around nine pounds. Picture an almost symetrical lens with 6" front lens, 5.25" rear lens with a Copal #2 in the middle - a deep waisted profile.
The lens would sit in a two-point cradle fastened (welded is fine) to a rail - round is good. Except for the back, there are no squared surfaces. Front and middle cradle points hold the very front of the lens (the only flat area up there) by a simple light pinch (not pressed), and the middle cradle is split with the top piece to pin the lens (gently) using sunken allens (like a scope mount). A third point is the tripod mount in front of the rear cradle. The bellows is anchored/swung from the very rear of the lens which, incidently, sits about 1" from the film. Bellows is about 2" deep (focus from very close to infinity is possible in that space).
Stainless would be nice, but aluminum will do.
I have tried plywood, and even laminated my own. Too weak for the thinness I want.
-
Phenolic resin will work for your application, as Donald suggested. Go to www.mcmaster.com and search under plastics for "garolite". It is a compressed paper/fabric material embedded with resin for a very rigid material. Circuit boards and film holder darkslides are usually made of phenolic resin. You can get it very thick. 1/8 and 1/4 inch thick will be rigid enough, at least in my experience. Work it like very dense wood. It is available in sheets, bars, and rods.
-Greg
-
Look into the materials used in aircraft cabinetry. Honeycomb should do the job, but it takes a bit of practice to work out the details of fastening and construction. tim
|
|