How to keep this spring from flying?

[Donald Qualls]

In attempting to change the frame mask on an RB67 ProS roll film holder (in order to visually distinguish the one converted for 35mm film and mask the sprockets), I found it very difficult to install the new mask plate and keep the return spring for the dark slide retainer in place.

This retainer prevents accidentally removing the dark slide when the roll film holder is not mounted on the camera (it's easily overridden, when necessary), by latching into a small notch on the edge of the dark slide. A small hairpin spring ensures it latches when the dark slide is inserted and the back dismounted.

This hairpin spring is retained only by the mask plate, and sits in a shallow well in the shell, so is prone to flying if it gets loose while trying to install the mask plate (especially if the mask plate in question is 3D printed, so may be a few thousandths off dimension here or there). Mine got loose; I found it on my desk, then it flew again and I heard it land in a box of crumpled paper packing material that I'm saving to ship my Graphic View in when I sell it.

I've now purchased a parts-only roll film holder (obviously missing some parts, but the mask plate and latch appear to be present, leading to presumption that the spring is as well), and I'd like to know if there's a trick to getting this little spring to stay in its place long enough to get the new mask plate seated and at least the first couple screws in. I've thought of laying a piece of business card stock over it, to be pulled out when the mask is almost seated, but I don't think that will hold the spring down into its well firmly enough. Suggestions?

 

[Mr Bill]

Hi, hard to say without knowing exactly what the situation is like, which I don't. But just a few possibilities (?); if the business card is too flimsy perhaps a piece of brass shim stock. Maybe even tie the spring onto the shim stock with something like thread or small twisted wires through small holes, in a manner such that they can be pulled out from the outside when things are nearly done. Maybe even a couple drops of hot-melt glue holding the spring down (I have no idea how strong the spring is) in such a manner that the ends of the spring will pull out of the glue droplets when the shim stock is pulled out.

Or if there's no obvious way to restrain the spring (or maybe it's not worth the effort) I've read suggestions to work inside of a clear plastic trash bag. At least the spring will have a harder time hiding when it gets away from you.

Best of luck.

Ps, fine copper wire is readily available by pulling strands out of a junk piece of lamp cord.

 

[Donald Qualls]

I had actually thought about glue last night -- the short leg of the spring just rests in the recess; I could probably super glue or hot glue it in place without affecting the movement of the free leg. Biggest trick is that none of the cured glue can stick up above the recess, and it can't get under the latch lever (else it'll lock it up). I think I can do it, though. Might have to grab a packet of the water-thin super glue (got a few days until the parts back arrives) at the dollar store.

 

[Nicholas Lindan]

Good advice above.

I work on a large fluffy white towel. It makes things easier to find after they go sproing. I also keep a bar of neodymium magnets in a plastic bag for sweeping the floor for springs, screws and ball bearings. If I am afraid something may really go flying I work inside a pillow case by feel.

 

[Donald Qualls]

I did in fact troll around with a couple strong magnets I keep in a plastic tube (like a 120 film can) stuck to my desktop computer case. No joy. I know the spring is magnetic; I picked it up with my magnetized screwdriver a couple times when I was trying to get it back where it belonged.

My very limited work space doesn't help; it's either my glass top desk (between the keyboard and the stack of negatives and camera stuff) or my small darkroom counter (currently occupied by multiple rolls of exposed film and a loaded daylight tank). I was at the desk; it's much more comfortable than bending low enough to see small parts on the darkroom counter.

 

[shutterfinger]

Thick grease. https://www.amazon.com/Tri-Flow-TF2...B,B0081JE2PQ,B0002ITTK2,B014LC7HS0,B00MWLD67O
or similar.

 

[Donald Qualls]

Thick grease. https://www.amazon.com/Tri-Flow-TF23004-Clear-Synthetic-Grease/dp/B000C15MUU/ref=sr_1_1?crid=1MVUYQJOURNO3&keywords=triflow+clear+synthetic+grease&qid=1637096291&qsid=137-0629206-6606764&sprefix=triflow+,aps,250&sr=8-1&sres=B000C15MUU,B000NORVHI,B00TP9T05S,B0083R1FME,B001AYL13A,B07RRF28VY,B07YHJK7MZ,B003L9K9HQ,B000BXKZQU,B000CQ4DK0,B0081JE0OO,B000UKUHXK,B000ILHVQ2,B000XBH9HI,B00MWLDALQ,B06WLQ251B,B0081JE2PQ,B0002ITTK2,B014LC7HS0,B00MWLD67O
or similar.

Also a thought -- I use that at work to hold small springs or balls in place when reassembling tools like cushion clutch screwdrivers. I'd be concerned about the grease migrating where it isn't wanted, though.

 

[ic-racer]

How to keep this spring from flying?

I simply told my wife we are driving for spring break...I think it will be quicker anyway.

 

[mshchem]

Old Bronica stuff I've seen has fingernail polish thread locker. Maybe that would work?

 

[Donald Qualls]

I simply told my wife we are driving for spring break...I think it will be quicker anyway.

Too late, the spring already boarded and departed; I didn't even catch what flight number or destination.

Old Bronica stuff I've seen has fingernail polish thread locker. Maybe that would work?

It might, but I've already got super glue on hand. As long as I keep it only on the short, fixed leg of the spring, I think that'll be the best method.

 

[gone]

A string or rubber band that you could cut after it's in?

 

[Donald Qualls]

A string or rubber band that you could cut after it's in?

I'll try to post a picture of the critical area soon -- I don't think this would work because of the way the mask and base plate fit together.

 

[Patrick Robert James]

Strong rare earth magnets or blue tack putty keeps things in place or catches them before they go flying off into the abyss. For some reason springs go places that they can never be found. They must be real shy. I can always find screws when I lose them but springs.. Even when I see the direction they go I still can't find them. Hope you solved your problem.

 

[Donald Qualls]

For some reason springs go places that they can never be found. They must be real shy.

At work, I fairly frequently find them again, days after I've gotten the replacement I ordered, completed the repair, and sent the tool out. I don't think they're shy, so much, they're just like a dog that's been in a pen for years. They want to go explore, and when they get hungry they come home.

 

[eli griggs]

Yep, some Camera Grease is the ticket, you only need a dab, use a horse syringe, Tractor Supply has them in their shots case (and dog shots, etc, that most folks ignore and fail to protect their friends with, because of vet costs) and get as thick a needle as can fit the spring hole; the smaller the number, the greater the girth.

Cheers.

Thick grease. https://www.amazon.com/Tri-Flow-TF23004-Clear-Synthetic-Grease/dp/B000C15MUU/ref=sr_1_1?crid=1MVUYQJOURNO3&keywords=triflow+clear+synthetic+grease&qid=1637096291&qsid=137-0629206-6606764&sprefix=triflow+,aps,250&sr=8-1&sres=B000C15MUU,B000NORVHI,B00TP9T05S,B0083R1FME,B001AYL13A,B07RRF28VY,B07YHJK7MZ,B003L9K9HQ,B000BXKZQU,B000CQ4DK0,B0081JE0OO,B000UKUHXK,B000ILHVQ2,B000XBH9HI,B00MWLDALQ,B06WLQ251B,B0081JE2PQ,B0002ITTK2,B014LC7HS0,B00MWLD67O
or similar.

 

[Donald Qualls]

Yep, I need to get a picture on this thread -- I was hoping to get input from someone who'd actually worked on this and knew what I'm looking at. Unfortunately, I keep forgetting when I'm at home...

@eli griggs The "well" this spring sits in is about 3/32" deep. Think of a hairpin with one leg shorter than the other, lying flat, and the well is just about as deep as the thickness of the wire.

 

[eli griggs]

OK, that's different from the coil spring I envisioned.

You have no tried loctite on the base leg so far, have you?

You might try do so without impediment to the spring's function, by using a Swiss watch oiller, which should allow a tiny droplet to be placed inside the well, instead of flooding the site, instead of, a regular drop of super glue, or a tooth pick would deliver.

Please post that pic of spring and location of where it's located on your specific kit, and, consider posting the same on a machinist forum, where they will know how to properly approach this question.

Cheers and The Best of Health.

 

[Donald Qualls]

I'm still waiting for the replacement part to arrive -- probably going to be a couple weeks, as my mail is being forwarded and I forgot to update the address on PayPal before purchasing. I think I can deliver a small enough drop of super glue to avoid impeding function; the short leg is fixed in place, and serves mainly to locate the spring.

 

[eli griggs]

I suggest you consider Loctite Red 262 or 271 which are medium high strength and high strength adhisive tools, like locking in place metal pieces/threads which can only be broken by heating to 500°f.

A good, fine tip soldering gun should prove good enough to release a bad fitting.

Cheers.

 

[Donald Qualls]

Those Loctite thread locking products are second cousins to the super glue I already have on my desk, and at $20 for a few grams, I'm very inclined to use what I have. It just didn't occur to me to do so before the original spring took flight.

 

[eli griggs]

Sounds like you've got it covered.

Let us know how it goes