loose screw issue

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RSG
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Location: Ontario, Canada

loose screw issue

Post by RSG »

Hi gang!

I'm hoping I can get some help regarding an issue I've been having with some center screws I use to lock a spool on a shaft that keep coming loose.

I use a thumb screw for the reels that I make which have a 6-32 thread, they are made from aluminum and anodized. The shoulder of the screw (.3"dia.) rests against the inner race of the bearing assembly and holds the spool on the shaft. When right hand anglers wind the reel they rub the screw ever so slightly with their hand eventually loosening it. They will sometimes catch it and retighten it but it can loosen again in short order. I have tried Loctite, epoxy on the face of the shoulder and even sand blasting the face but some reels just keep loosening while many others don't seem to be affected. I'd appreciate any input as it has alluded me for some time. Yes I have thought of left hand threads but fear someone might forget and pry the screw off breaking it off in the spindle. I've also thought of engineering a sophisticated slip style of the screw requiring compression to engage but it's far too complicated to machine considering the size.

Here's a pic of the assembly.

Image


Any thoughts would be appreciated.
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mcostello
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Re: loose screw issue

Post by mcostello »

Try a piece of fishing line in the threads.
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GlennW
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Re: loose screw issue

Post by GlennW »

Re-design it so the thumb screw is on the other side away from the hand crank. (Flip the assembly 180°)
Glenn

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SteveM
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Re: loose screw issue

Post by SteveM »

Can you drill / tap a hole in the opposing side to insert a screw from the other side to butt up against it and lock it?

Steve
John Hasler
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Re: loose screw issue

Post by John Hasler »

Rather than putting fishing line in the threads cross-drill the threaded section and press a piece of nylon fishing line into the hole and cut it off at the major diameter. That's essentially how Nylok screws work.

https://nylok.com/products/nylok-torq-strip
RSG
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Re: loose screw issue

Post by RSG »

mcostello wrote: Sun Apr 26, 2020 7:47 pm Try a piece of fishing line in the threads.
That actually does work! But how do I tell a customer who spent 2G on a reel to fix it with some fishing line :lol:
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RSG
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Location: Ontario, Canada

Re: loose screw issue

Post by RSG »

GlennW wrote: Sun Apr 26, 2020 7:52 pm Re-design it so the thumb screw is on the other side away from the hand crank. (Flip the assembly 180°)
Good idea and I used to do just that but I haven't shown what going on at the back in my drawing. There's a whole compression lock system that's missing in the drawing, It's simply too big to put on the reel face side so it must stay on the backplate side.
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RSG
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Re: loose screw issue

Post by RSG »

SteveM wrote: Sun Apr 26, 2020 8:35 pm Can you drill / tap a hole in the opposing side to insert a screw from the other side to butt up against it and lock it?
Unfortunately no. It has to be something the guys can deal with on the river to dismantle the spool should dirt enter the backplate. With only a .005" gap between the spool lip and the backplate lip even the smallest bit of grit can foul the spin of the reel.
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RSG
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Re: loose screw issue

Post by RSG »

This is intriguing! I wonder if I actually used a slitter saw to cut a slot across the face, then wedge a piece of nylon in it. The hole with fishing line it a possibility as well. Do you think I would need epoxy or another glue to hold it in place?
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RSG
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Re: loose screw issue

Post by RSG »

I was also contemplating this idea, where the thread was part of the spindle! It could maybe have a nylon pin in it too. Do you think it would be better at stopping this loosening issue?

Image
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SteveM
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Re: loose screw issue

Post by SteveM »

Can you press fit a nylock nut into the handle?

If you used a threaded rod as an arbor, probably supported by the tailstock, you could turn the flats off a nylock nut and either make it a press fit into the handle or use locktite.

Nylock nuts are available in stainless, which is probably what you would need.

Steve
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warmstrong1955
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Re: loose screw issue

Post by warmstrong1955 »

Can you make a smaller diameter thumb screw for RH people? Maybe a less aggressive knurl? Get rid of the lobes?

Also, have you ever used V-3? It’s similar to Loctite, but works more like a patch or nylon insert screw.
Spray it on, let it dry, and assemble. You can still adjust it, but it increases the friction to do so, and will last a while.

Bill
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