Wetplate darkbox shroud/camera bellows liner replacement fabric found

[Joe Smigiel]

I've found a replacement for the shroud/bellows material Freestyle and Porter's used to sell. It is called BK5 fabric and is available from Thor Labs. It comes 60" wide x 3 yds long for $44.20 USD. Other continuous lengths can be specified. The material is 0.005" thick making it lightweight and flexible. I tried to stretch and scratch it, but it resisted that minor abuse and seemed pretty sturdy.

I requested a sample last week and they sent one to me very quickly. It is very similar in weight and flexibility to the old stuff sold by Freestyle and Porter's. The rubberized side is a bit shinier than the old fabric, but it should work well.

I tested it by exposing a piece in contact with some photo paper in a contact printing frame. For the first test, I stuck the frame about 2" from a set of UV BLB lamps in my handmade exposure unit for about 5 minutes. After developing the print, the weave pattern of the fabric was discernible but the fabric only let through enough light/UV for it to be a very light gray while the unprotected area went black immediately.

I ran a second test exposed in the contact frame under normal fluorescent room lights for about 20 minutes. I saw no evidence of exposure on the side covered by the fabric (either in a single or double layers).

I'll probably order about 12 yds of the stuff immediately to have on hand.

Joe

[jon.oman]

Great find!

Jon

[JRFrench]

Thanks for that Ive been looking for something like this to make some bellows from. I was going to have to resort to buying a changing bag. Now to find someone I can forward this to in the states so I can avoid the $95 they want to FedEx it to me!

[Colin Graham]

Excellent! Thanks Joe.

[BarryS]

I ordered 3 yards of the same material and received it last week. I'm going to restore some Thornton-Pickard roller blind shutters and build my first bellows. It looks like an excellent fabric, although it should probably go on the outside of a bellows laminate due to the slight sheen. Thor Labs has great service and they shipped my fabric the day after I ordered and followed up by phone. They even included a box of "lab snacks" in the package. The shipping charge was very reasonable and you can choose the carrier.

[eddie]

thanks. this sounds great

[IanMazursky]

Very cool find! Ive been using dark bags from film boxes and rolls but this is much better.
The bags are a pain to use since they come coated with corn starch or something like that.

[Jim C.]

Not to rain on everyone's parade, but I also ordered the same cloth from Thorlabs and
my initial test in trying to glue the material with contact cement failed on the
'rubber' side, and it wasn't user error either. I have a email in to tech support to
find out what exactly the coating is made out of, I suspect it's either a vinyl, or a
urethane, with urethane being top on the list since I use a vacuum bagging film
that has a similar feel to the coating.

I also ran a opaqueness test using a hi intensity LED flashlight, since I'm making camera bellows
for a restoration and it will probably work providing the outer cover of the bellows is opaque enough.

Left side of the image is one layer, right is two layers

[Clarence Rhymer]

Hello all,

To those of you who have some in hand, I have two questions. Does it appear to be thin and flexible enough for a Thorton Pickared roller-blind shutter? What do you think the smallest bellows would be that could be made with this product? I realize this is a matter of opinion and estimation, but I just got a Cambo Legend, and the bellows fold down to naught.

Thank you.

Cheers,
Clarence

[Jim C.]

Clarence, the Thorlabs BK5 fabric is extremely thin, .005" thick, about as thick
as a sheet of paper and is very flexible, takes folds ok, it's not stretchy so I would
guess that it may make a good shutter cloth for the Thorton Pickard as long as
it's not used on the bias.

My feeling is that it could be used for the inner bellows lining for any size
bellows depending on how thick the outer covering and the ribs would
be, the quantity that Thorlabs sells is quite alot, and is very reasonable in price when you
break it down, 5 ft wide ( 60" ) x 9 ft ( 3yds ) compared to pneumatic bellows cloth
at about $30 per yard X 42 " width.
The only minus is that the cloth side has a sheen to it, not totally matte.

I think would also make a great dark cloth.