Black Kevlar fabric for bellows?

[Kino]

I just ran across this and wondered if anyone had ever attempted to use this in the making of a camera or enlarger bellows?

https://www.ebay.com/itm/283456209473?chn=ps&mkevt=1&mkcid=28

 

[MattKing]

Do you mean "Kevlar" fabric rather than Kelvar? If you need help correcting the title, don't hesitate to ask.

 

[Kino]

Woops! Thanks Matt...

 

[BAC1967]

I'm not sure what the benefit would be unless you're taking your camera into a war zone. I would think it would be hard to cut and get folds to crease. I've never worked with Kevlar but I have mad a few bellows so I'm making assumptions here.

 

[Tel]

Nowhere in the description does it seem to say "light tight". Kevlar is made for tensile strength--doesn't mean light can't get through it. I used to buy a rubber-coated ripstop nylon from Micro-Tools for this purpose but I don't see it in their catalog anymore.

 

[Luckless]

Haven't used it for a bellows, but any kevlar [or carbon fibre] fabric I've worked with for other things in the past has had fairly obvious pin-holes in the weave.

Very low weight kevlar might make a decent base material, slightly stronger than nylon and a bit more wear resistant, but I would expect to have to coat and double layer kevlar to make a fully light tight fabric. But unless I had access to kevlar cut-off rolls, I don't think I would bother paying the extra for it over nylon or other more common synthetic thread materials.

I would also be wary of ordering from random online stores for kevlar. If you're not paying the premium for sourcing from a large reputable source you're running the risk of it being cheap nylon anyway.

 

[Kino]

Just thought the strength might be advantageous somehow.

@ Tel -- Here's some Polyurethane coated ripstop; think I'll order some samples...

https://www.seattlefabrics.com/60-1...ut-Nylon-Ripstop-1150-linear-yard_p_1097.html

 

[Tel]

Like the "black-out" part of the description. Looks like the right stuff.

 

[Kino]

Ok, I ordered some polyurethane and silicone impregnated ripstop examples along with a swatch of Blackout fireproof duvetyne. Will report on it when I get it.

 

[osella]

Here's some Polyurethane coated ripstop; think I'll order some samples...

https://www.seattlefabrics.com/60-1...ut-Nylon-Ripstop-1150-linear-yard_p_1097.html

I actually just bought some of this(with white coating) to use as a dark cloth as I couldn’t find one the size I wanted.

It appeared to be pinhole free, and it’s very light. It may be a little thick for bellows, but I can measure the thickness of you are interested.

 

[gone]

That Kevlar fabric might work, if it's light tight. It's a blend though, and I didn't see on the ad what percentage of it is actually Kevlar. I've owned Kevlar bike tires, they would only resist big things like glass, while small, sharp thorns went right thru the weave.

 

[BAC1967]

Just thought the strength might be advantageous somehow.

@ Tel -- Here's some Polyurethane coated ripstop; think I'll order some samples...

https://www.seattlefabrics.com/60-1...ut-Nylon-Ripstop-1150-linear-yard_p_1097.html

I live near Seattle, my wife used to drag me to that store all the time for her sewing projects. They do have a lot of great stuff for outdoor clothing, tents, bags and such.

Sandeha Lynch recommended I get Thorlabs BK5. He sent me a small piece that I used to make a small bellows for a Kodak Vest Pocket Autographic. It’s thin material but doubled up on a bellows it worked great. It may be thinner than you want for a large format camera but could be used as the inner layer if you’re using something thick for the outer layer. I’m going to order some more for a few projects.

https://www.thorlabs.com/thorproduct.cfm?partnumber=BK5

 

[Kino]

I actually just bought some of this(with white coating) to use as a dark cloth as I couldn’t find one the size I wanted.

It appeared to be pinhole free, and it’s very light. It may be a little thick for bellows, but I can measure the thickness of you are interested.

Thanks Osella! The thickness would be interesting. I ordered some sample patches but they probably won't be here for at least a week.

 

[Kino]

That Kevlar fabric might work, if it's light tight. It's a blend though, and I didn't see on the ad what percentage of it is actually Kevlar. I've owned Kevlar bike tires, they would only resist big things like glass, while small, sharp thorns went right thru the weave.

If it's thin enough, I thought it might be worth double layering with weave at 45 degrees to each other. I'm not looking to stop projectiles, just extend the life of the corners a bit.

I live near Seattle, my wife used to drag me to that store all the time for her sewing projects. They do have a lot of great stuff for outdoor clothing, tents, bags and such.

Sandeha Lynch recommended I get Thorlabs BK5. He sent me a small piece that I used to make a small bellows for a Kodak Vest Pocket Autographic. It’s thin material but doubled up on a bellows it worked great. It may be thinner than you want for a large format camera but could be used as the inner layer if you’re using something thick for the outer layer. I’m going to order some more for a few projects.

https://www.thorlabs.com/thorproduct.cfm?partnumber=BK5

Interesting! Always good to have options; I'll check it out. Thanks!

 

[osella]

Thanks Osella! The thickness would be interesting. I ordered some sample patches but they probably won't be here for at least a week.

The thickness of the coated nylon is in the around .007-.008in thick. One other thing I hadn’t noticed was that it has a little stretch and it seems to keep a crease which might be good for bellows.

 

[Kino]

The thickness of the coated nylon is in the around .007-.008in thick. One other thing I hadn’t noticed was that it has a little stretch and it seems to keep a crease which might be good for bellows.

Good to know! Thanks!

 

[Warm Winter]

Actually, I think a couple 8x10 deardorff made "new" with NOS parts used kevlar fabric for bellows. I know the one was kevlar fiber and organza silk, I think the other was just kevlar. I think catlabs had them but they seem to have sold. I forget who the builder of them was, they may have more information.
Provided it's light tight or close enough, it'd be nice. It's not going to be bullet resistant or anything but it'll be resistant to wearing out at the folds or getting cut or torn on accident.
It's been done before so should be doable, it just wouldn't be fun as kevlar is horrible to work with.

 

[Kino]

Got in my samples from Seattle Fabrics, Inc. and I have to say the 1.9 oz. Polyurethane Coated Black-out Ripstop fabric should make very nice bellows. It is very thin, flexible and quite opaque; a high intensity LED flashlight directly held against the surface allows no light to penetrate. The fabric comes in two styles: Black nylon with a white poly coating and black with a black poly coating. I can't see making a bellows with the white coated material, but it would make a fine changing tent/bag or focus cloth if weights are sewn onto the corners.

At $10.50 a yard (60 inches wide), its very reasonably priced in my opinion.

The Duvetyne Black Out Fabric is also very nice, but is not as light proof as the above and is 2 to 3 times as thick as the above. I would suggest two layers for blocking light on a darkroom window, as you can see tiny pinholes of light with the same LED flashlight pressed up against the fabric. It would be great for dark gobos or other light absorbing duties, but does need to be doubled for absolute light tightness. I don't think it would be good bellows material for obvious reasons...

This fabric is also very reasonably priced at $15.95 per linear yard (54 inches wide).

 

[ckleib]

Got in my samples from Seattle Fabrics, Inc. and I have to say the 1.9 oz. Polyurethane Coated Black-out Ripstop fabric should make very nice bellows. It is very thin, flexible and quite opaque; a high intensity LED flashlight directly held against the surface allows no light to penetrate. The fabric comes in two styles: Black nylon with a white poly coating and black with a black poly coating. I can't see making a bellows with the white coated material, but it would make a fine changing tent/bag or focus cloth if weights are sewn onto the corners.

At $10.50 a yard (60 inches wide), its very reasonably priced in my opinion.

The Duvetyne Black Out Fabric is also very nice, but is not as light proof as the above and is 2 to 3 times as thick as the above. I would suggest two layers for blocking light on a darkroom window, as you can see tiny pinholes of light with the same LED flashlight pressed up against the fabric. It would be great for dark gobos or other light absorbing duties, but does need to be doubled for absolute light tightness. I don't think it would be good bellows material for obvious reasons...

This fabric is also very reasonably priced at $15.95 per linear yard (54 inches wide).

Hi Kino, I know this is a bit of an old post, but wondering if you have made bellows from the 1.9oz Polyurethane Coated Black-out Ripstop fabric? Or have any other thoughts on it since December? I've just bought an 8x10 Korona that needs new bellows and I've been digging into fabric options. I was looking at that coated ripstop fabric. Would you suggest both layers for that? Or the inner layer in that and outer in the Duvetyne? Some other combination?

60

www.seattlefabrics.com

54

www.seattlefabrics.com

 

[indy_kid]

I've used regular cotton fabric from either Joann's or Hobby Lobby. No issues with light leaks along the seams.

I've applied black Flex-Seal rubber coating to the exterior, then smoothed it out. It fills in the gaps, provides some water protection, and is flexible without tearing the rubber.

 

[AgX]

That Kevlar fabric might work, if it's light tight. It's a blend though, and I didn't see on the ad what percentage of it is actually Kevlar. I've owned Kevlar bike tires, they would only resist big things like glass, while small, sharp thorns went right thru the weave.

Maybe the OP did not only think of the strength of Kevlar (which is kind of yellow) but also mixed it up with carbon fibres (also very strong but black).


Yes, I just experienced a thorn induced pinhole-puncture in a "puncture-save" Kevlar tire...
A plain pin can be pushed through such tire with the top of a thumb.

 

[Murrayatuptown]

I think John Minnicks used some form of Kevlar for Graflex FP shutter overhaul. I don't remember if he discussed it in an interview or an e-mail (I bought some lenses from him), but he had specific requirements and precautions. IIRC