Film strap fixing for my Rondinax

ChrisR

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I have to start this post by saying, clearly I've been... rather daft. But I'm relying on you lot to help me recover from the impacts of my daftness!

So, I have a Rondinax 35 daylight developing tank. Very neat device, no messing around in dark bags to get the film on the reel. You just drop the canister in, pull out the end, clip it onto a strap, put the lid on, wind the winder which pulls the film out onto the reel, When it stops, there's a guillotine to cut the film (doesn't work with ployester-based films, but that's another story, no Rolle Retro for me!), then you wind the rest in. Develop much as with a normal tank, except there's only half the quantity of solution so you need to keep winding. That's just for background, and as they say in the adverts, some steps omitted; that is NOT the full operating instructions!

This is what it looks like, looking down with the top off. Notice the strap and the clip.

Rondinax strap 1.jpg

That's pretty OOF but I hope you get the idea.

Now to the daft part. A few weeks after I got it, the film clip came loose from the strap. The strap just loops through the clip, but then needs to be fastened back on itself. I couldn't work out how to fix it... so I stapled it! All seemed to be well, though as the months roll on I have noticed little specs in the stop bath and fixer, and on some of my negatives. Thos little specs are becoming little rocks. I suddenly thought, that stop bath is acidic, there are other strong chemicals, you've used a metal stapler, that is... daft:

Rondinax strap 2.jpg

So, now there are two possibilities:

a) I could replace the strap with... a replacement strap. I think this would have to be fabricated, as I don't think I'd get one new. The replacement had got to be fixed onto the central spindle, and also onto the film clip.

b) I could remove the staples, clean up the rust stains, and find a way to fix the strap back to the film clip. While it might be hard to visually remove the rust stains, I think if the metal staples are removed the worst of my rust fragment problems will be over. But how to fix it? Note, the first solution also requires answers to this question!

So folks, what should I do?
 
a) Does the reel come out and if so, does it look straightforward to take apart? If yes to both then it should come down to choosing the right material for the strap, ordering a sheet of it and cutting a piece to size. I'm no expert when it comes to material identification, I'm not even an incompetent amateur, but something like these 0.5mm polypropylene sheets looks to be the sort of thing you're after.

b) You could cut off the rusty part if you've enough slack to move the clip further down or remove the staples and try cleaning the strap with a scouring pad and water, then reattach the clip using an appropriate glue to hold the folded over part of the strap in place, depending on how much 'spring' is in the strap material. You might have to clamp it while it dries if it wants to open up, so clothes pegs could be suitable for that.

Lots of ifs, buts and maybes in that but I felt I had to respond to a strap question given my forum nickname.
 
I wonder if the brass fixing thingies would do a better job? The kind you push through paper and fold? Either some kind of press stud or those eye let wotsits you get on jeans?
 
a) Does the reel come out and if so, does it look straightforward to take apart? If yes to both then it should come down to choosing the right material for the strap, ordering a sheet of it and cutting a piece to size. I'm no expert when it comes to material identification, I'm not even an incompetent amateur, but something like these 0.5mm polypropylene sheets looks to be the sort of thing you're after.

It is possible to remove the spiral (in fact it's recommended, though I've never done it). I don't know how easy to disassemble after that.

That material does look reasonable, depending on flexibility and strength. It's quite a stiff pull getting the film into the spiral sometimes (depending on how well I've trimmed the corners and bent them in), and then of course you hit a block when you get to the end of the film; sometimes it's been hard to distinguish the pull from the stop.

b) You could cut off the rusty part if you've enough slack to move the clip further down or remove the staples and try cleaning the strap with a scouring pad and water, then reattach the clip using an appropriate glue to hold the folded over part of the strap in place, depending on how much 'spring' is in the strap material. You might have to clamp it while it dries if it wants to open up, so clothes pegs could be suitable for that.

Lots of ifs, buts and maybes in that but I felt I had to respond to a strap question given my forum nickname.

I don't think there's enough to cut the end off. I think it'll have to be remove the staples and clean. What sort of glue would survive in that environment?
 
What sort of glue would survive in that environment?
Sorry, Chris, you'll have to wait for Gluey to log in to answer that one. :confused:

I wouldn't use superglue on the basis that as Nikkorr states, it can cause more problems than it solves with certain plastics and it only ever seems to be a temporary solution whenever there's the slightest bit of spring pressure on a join, at least when I use it. I assume you'd want some sort of waterproof glue that's neutral in dev chemicals (@stevelmx5 might have some better ideas such as the gorilla glue he mentioned in his 5x4x5 thread). I'd probably wrap it a couple of times with sellotape and see how it goes.

You could try making up a dev solution and leaving the taped-up strap end sitting in it for half-an-hour to see if it holds? It'd save you finding out that it doesn't when processing a film.
 
Maybe a nylon thread and needle, doesn't need to be an amazing job to work I should think.

This has a few ideas on replacing the belt if you ever need: https://rondinax.wordpress.com/2014/05/02/rondinax-replacing-the-belt/
(note, not all materials react well with superglue)

I knew of that post, thanks... in the end it doesn't say a huge amount that's really helpful!

My sister has suggested sewing it. She has a sailmaker's awl to make the holes, and suggests a simple over-stitch (rather than a saddle stitch with two needles) would be suitable. Unfortunately I'm staying with her at the moment, and the Rondinax is at hoe!
 
Pierce tiny holes. Hot melt glue gun weld. Clamp so glue squeezes through holes. Test on sample first to ensure glue doesn't melt the strap.

That was interesting, first time I've really looked at glue guns. Wikipedia suggests a couple of glue types that work well in chemically hostile environments, but the cheaper end of the market doesn't seem to advertise what their glue comprises. I'm a bit worried about melting it, too; there's not really much spare to be a test sample.I think I should try sewing first.
 
My only concern with stitching is that you run the risk of weakening the strap by putting holes in it for the thread.

For adhesive, I'd use a 2 part epoxy and clamp the pieces together for 24 hours with a thin layer of adhesive between them. Once it goes off you'll end up with a solid watertight joint that should resist stretching and won't add any bulk to the strap.
 
My only concern with stitching is that you run the risk of weakening the strap by putting holes in it for the thread.

For adhesive, I'd use a 2 part epoxy and clamp the pieces together for 24 hours with a thin layer of adhesive between them. Once it goes off you'll end up with a solid watertight joint that should resist stretching and won't add any bulk to the strap.

So, like araldite? I have some of that!
 
Well, after a close look, I decided the sewing option wasn't going to work too well; only two staple holes were over the bit where the strap overlapped itself, and they were pretty blocked up. It was a job getting the old staples out, and it felt like bits of them were still stuck in the strap. However, I figured they would dissolve over time, and represented much less metal than the staples themselves. All cleaned up, glued with araldite, re-assembled, left for several days, and today I did a session, which seemed to work well enough.

I've been a bit worried that the araldite might be a bit brittle, but in fact I don't think there's much real bending at that point. Anyway, thanks @stevelmx5 and we'll see how it goes. :)
 
Well, after a close look, I decided the sewing option wasn't going to work too well; only two staple holes were over the bit where the strap overlapped itself, and they were pretty blocked up. It was a job getting the old staples out, and it felt like bits of them were still stuck in the strap. However, I figured they would dissolve over time, and represented much less metal than the staples themselves. All cleaned up, glued with araldite, re-assembled, left for several days, and today I did a session, which seemed to work well enough.

I've been a bit worried that the araldite might be a bit brittle, but in fact I don't think there's much real bending at that point. Anyway, thanks @stevelmx5 and we'll see how it goes. :)

Sounds like a successful repair Chris, happy to help :0)
 
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