Bellows Material

[martiansea]

I see your point about the flocking potentially wearing off, but I'm still curious about this particular fabric, since it's intended for high-wearing exterior use. I'll make an effort to test its durability and judge from there.
Real leather is an attractive possibility, thanks for that link, but I worry that with a bellows this large it may be difficult to get a continuous piece large enough? I'm just wary of the actual dimensions of the piece working out for this. Giving an area in ft2 seems meaningless considering that area needs to fit to a specific dimension. I wonder what kind of leather was commonly used for very long bellows in the past, what animal it was from?
The tip I saw to use Yupo for the ribs is brilliant. Definitely going to do that. I was already thinking any kind of stiff paper or cardstock would be a bad idea for long-term durability - look at all those old bellows with ruined paper ribs.

[Jim C.]

As you said, that flocked material is for exterior use, using it as a bellows liner is probably not going to
end well after all that work, that's just my opinion. Talas does not mention how thick the material is,
but flock fibers are electrostatically applied and the fibers are perpendicular to the surface, that adds thickness.
You can always contact Talas to see if they can give you a thickness measurement before spending any money.

In regards to getting leather skins large enough to do one 8x10 bellows I guess it depends on the
how big the animal was certainly not goat, cow ?
The remnants of my 2D bellows show that the skin was big enough to cover 3 sides of the bellows and
the fourth side was a separate panel, there is a distinct lap line showing it.
If you have the old Seneca bellows you should examine it for signs of how many pieces were used to cover.
Making a flat paper pattern would help in sizing the skin, you could send that to potential supplier to see if they
can size a skin based off your pattern.

Never heard of Yupo, but a cursory look seems like it's polyethylene 'paper' , it's got my interest.
There's nothing wrong with card stock for stiffener ribs, all those old bellows you mention are 50-100+ years old ?
Aside from age, neglect and mishandling the cardboard ribs can hold up quite well.

[martiansea]

Yupo is interesting stuff. Thin plastic sheets with a slight bit of texture for painting on. It's popular for people to do psychedelic abstract paintings with alcohol ink on it. I experimented with it a bit for gum printing, and it can work well if it is suitably prepared with some textured sizing - the gum the falls right off otherwise. I've seen people using it for carbon printing support tissues as well.

I checked the original Seneca bellows. Appears to be a single piece of leather; only see one seam along the bottom side. Unless it's fake leather? I dunno if that was a thing yet at the time it was made...camera is likely from early 1920's-ish. It's a tapered bellows, so perhaps an odd-shaped skin works with it. But honestly, finding a suitable piece of leather seems like too much trouble for this. Maybe I'll save that idea for a smaller one.
My swatches from Talas should be arriving soon.

[martiansea]

Received the swatches today. It appears the flocked black "Laval" doesn't block light very well at all. It does better than the other bookcloths, but the others are positively porous. So, that seems like a bust either way. Glad I got swatches. But some of the bookcloths are very attractive The "Duo" ones especially look really cool. If I used something completely blocking for the interior, maybe I could use one of the attractive bookcloths for the exterior.
I was looking at the page for the Thorlabs BK5 and found they also have self adhesive black flocked paper (BFP1) that "Does Not Shed Dust or Lint." Thinking about it. I'm of the mind that the interior must be as nonreflective as possible, especially considering how long it is.
I'm going to the local fabric store tomorrow and see what they have, maybe I'll get lucky and not have to order anything. Would be a pleasant surprise.
Close to just buying one ready made, but I'd really like to DIY this rebuild as much as possible, for the experience of it.

[martiansea]

Very pleasant surprise indeed. I went to the fabric store and found something that seems perfect. It's a fake leather "pleather" fabric made of polyester and spandex. It's very thin, slightly stretchy and absolutely blocks out light excellently. The brand is Yaya Han and the material is called YH 4-Way Pleather Black. It's 54" wide and was about $16/yd.

It looks and feels very much like the material on the exterior of my Cambo's bellows.
I got some stiffer "linen-like" black cloth to use for the interior. Hopefully that will keep it from being too saggy.
Next step is to experiment with gluing some scraps together to test out this glue I got. It's Loctite brand professional spray adhesive. I got it because it's what the lady at the store recommended would be the best choice for gluing the pleather. We'll find out.

[pacviewcam]

Some years ago I used to be able to buy blackout cloth from Freestyle Photo. Sad to say, they had to stop carrying it when the minimum order was changed to a container load -- you know, those containers that they load full of stuff and then carry on ships and semi trucks.

That stuff was .008" thick, and just thin enough; any thicker would have been too thick.

Then, I discovered on here someone recommending the Thorlabs stuff. It measures in at .005" thick and is really great. Use card stock for ribs. If you can get Weldwood contact cement (the toxic stuff, not waterbase) use that to glue the outer layer of Thorlabs material to the bellows. Barge contact cement works well too, available from shoe repair and/or leather suppliers.

I've never had a problem with light leaks from a single layer of the Thorlabs stuff.

For the liner (inner layer) I use cotton, the thinnest most flat black I can find. A good fabric store will have much to choose from. Bring your light meter and get the thinnest lowest-reflectance stuff they have.

Re Columbia Leather: I've often drooled over what they have, but the price is just too high for any large format bellows. I could see spending that much for a folding 120-film size camera, but for a view camera it'll break the bank.

I don't know how many bellows I've made, but doing so helped me make a living during a few recessions when I'd build the bellows for view cameras I was refurbishing to sell; would also sometimes build them to order.

The main thing is that the two fabric layers have to be thin enough to give you a good sharp crease, and all those folds have to compress into a very small space. So every thousandth of an inch makes a difference.

[Jim C.]

It looks and feels very much like the material on the exterior of my Cambo's bellows.
I got some stiffer "linen-like" black cloth to use for the interior. Hopefully that will keep it from being too saggy.
Next step is to experiment with gluing some scraps together to test out this glue I got. It's Loctite brand professional spray adhesive. I got it because it's what the lady at the store recommended would be the best choice for gluing the pleather. We'll find out.

As pacviewcam said, thickness matters and it's misleading when you go by 'feel', I'd recommend getting a cheap pair of digital machinist calipers
to measure what you're buying.

Some years ago I used to be able to buy blackout cloth from Freestyle Photo. Sad to say, they had to stop carrying it when the minimum order was changed to a container load -- you know, those containers that they load full of stuff and then carry on ships and semi trucks.

That stuff was .008" thick, and just thin enough; any thicker would have been too thick.

Then, I discovered on here someone recommending the Thorlabs stuff. It measures in at .005" thick and is really great. Use card stock for ribs. If you can get Weldwood contact cement (the toxic stuff, not waterbase) use that to glue the outer layer of Thorlabs material to the bellows. Barge contact cement works well too, available from shoe repair and/or leather suppliers.

I've never had a problem with light leaks from a single layer of the Thorlabs stuff.

For the liner (inner layer) I use cotton, the thinnest most flat black I can find. A good fabric store will have much to choose from. Bring your light meter and get the thinnest lowest-reflectance stuff they have.

Re Columbia Leather: I've often drooled over what they have, but the price is just too high for any large format bellows. I could see spending that much for a folding 120-film size camera, but for a view camera it'll break the bank.

I don't know how many bellows I've made, but doing so helped me make a living during a few recessions when I'd build the bellows for view cameras I was refurbishing to sell; would also sometimes build them to order.

The main thing is that the two fabric layers have to be thin enough to give you a good sharp crease, and all those folds have to compress into a very small space. So every thousandth of an inch makes a difference.

I've ordered leather from Columbia for a non bellows related project and I was very impressed at the quality of the leather,
years ago while searching for materials for bellows and focal plane shutters, I found an almost exact match for the interior
lining and for focal plane shutters, it was pneumatic bellows cloth for player pianos, .008 thick rubberized cotton fabric and as I recall
it was 50" wide and sold by the yard. Unfortunately the vendor went out of business, but there are other vendors that sell a nylon cloth version.

Never had luck with any of the cements you mentioned with the BK-5, they never survived my peel test, the only one that did was a vinyl cement ( HH-66, RH Products )

[Dan Dozer]

I have had a lot of success with the inner layer using drapery black out material and thin black Egyptian cotton on the exterior (looks really nice). I could only find the drapery fabric in white (it is kind of like coated fabric) so I just used some flat black paint to paint the interior surface and it worked very well.

I tried other things from the fabric store that was like imitation leather. Some of it seemed thin enough but I couldn't get the creases to form well enough.