Author Topic: EBB screw protector/saver  (Read 2345 times)

in4

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EBB screw protector/saver
« on: May 03, 2023, 04:05:43 pm »
Probably covered already but:
Mindful of the conditions my Nomad has recently come through I thought it a good idea to protect the EBB screws, as far is feasible. Experimenting thus: piece of inner tube ( I had one of a road bike) cut a length off and cut two slits in the tube. Keep them small and spaced so as you have to stretch the tube from one screw to the other. I might use a couple of small cable ties but for now, it looks like this: 

mickeg

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Re: EBB screw protector/saver
« Reply #1 on: May 03, 2023, 05:27:33 pm »
I do not know if that could trap and hold water where you have metal that can corrode.  I like it when any place that can get wet can easily dry out. 

I am sure that my eccentric bolts (Nomad Mk II) get wet every time I ride through a puddle, but they can quickly dry out.

The rubber bands are to make sure that a bolt can't unthread from vibration if it gets loose.

in4

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Re: EBB screw protector/saver
« Reply #2 on: May 03, 2023, 06:25:10 pm »
Good point re water. I’ll leave the ‘rubber sleeve’ open-ended and monitor for a while. I think your solution was at the back of my mind when I thought I’d try this out.

PH

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Re: EBB screw protector/saver
« Reply #3 on: May 05, 2023, 10:05:28 pm »
Not sure I like the idea, whatever you do it's going to trap dirt and moisture.  Best protection for the underside of a BB is to keep the nasty stuff off with a long mudflap, second line of defence for me is to use plenty of marine grease. 

Danneaux

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Re: EBB screw protector/saver
« Reply #4 on: May 05, 2023, 10:10:15 pm »
I use thin stainless "jam" nuts on my eccentric screws. They only require a very small torque, given the fine thread size. The bosses on my Nomad are stainless, but to protect the powdercoat, I still place a thin stainless flat washer under the jam nut.

Cost was about USD$3 for the lot on eBay, including shipping.

Works a treat for me. :)

Best, Dan.

Matt2matt2002

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Re: EBB screw protector/saver
« Reply #5 on: May 06, 2023, 09:03:46 am »
Is a jam nut like a split washer?

Matt
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PH

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Re: EBB screw protector/saver
« Reply #6 on: May 06, 2023, 09:44:31 am »
Is a jam nut like a split washer?

Matt
My guess is it's an Americanism for a lock nut, a thin nut to go under the head of the screw and against the EBB shell.
If so that's a pretty good idea, does it need a thin spanner to tighten it? 

Matt2matt2002

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Re: EBB screw protector/saver
« Reply #7 on: May 06, 2023, 11:20:55 am »
Is a jam nut like a split washer?

Matt
My guess is it's an Americanism for a lock nut, a thin nut to go under the head of the screw and against the EBB shell.
If so that's a pretty good idea, does it need a thin spanner to tighten it?

Ah yes  Your suggestion makes sense.
We'll wait for Dan to surface in USA.😉
Matt
Never drink and drive. You may hit a bump  and spill your drink

mickeg

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Re: EBB screw protector/saver
« Reply #8 on: May 06, 2023, 11:47:51 am »
I have been content with the standard bolt that comes on the frame for the eccentric.  Having a bolt with a 15mm wrench size (same as a pedal) is convenient.  One of mine worked loose early in my experience with that bike.  I tried a removable thread locker, but decided later I did not like that, so cleaned that off.  Then went with a rubber band.  Actually a pair for when one breaks, redundancy is good.  I also bought a spare bolt to carry on tours.

Some time back I elaborated further on how I adjust the chain, that involves removing one of the screws, thus the thread locker was an inconvenience.    That description is here:
http://thorncyclesforum.co.uk/index.php?topic=14475

Danneaux

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Re: EBB screw protector/saver
« Reply #9 on: May 18, 2023, 10:44:24 pm »
Paul pondered...
Quote
My guess is it's an Americanism for a lock nut, a thin nut to go under the head of the screw and against the EBB shell.
If so that's a pretty good idea, does it need a thin spanner to tighten it?
...and Matt commented...
Quote
Ah yes  Your suggestion makes sense.
We'll wait for Dan to surface in USA.😉
...and Dan replies (wondering how this question was missed! I usually get them all and right away...)

Yes! Paul has it. These are simply thinner nuts with the same threads that spin on the shaft of the machine/grub screws that hold the eccentric in place. Because the eccentric screw threads are so fine (M8 x 0.75...same as chainring bolts), the jam nuts don't have to be tightened very much to lock things in place -- just a bit more than finger tight will do it. Mine happen to be 3mm thick and 12mm across the flats, so they do require a wrench specific to them or (shudder!) pliers (as the torque needed is so very low). I use my needlenose Vise-Grips (think: MoleGrips) for the task and have no problems with scarring or rounding, again because the torque needed to lock everything in place is so little.

They do work a treat and I made sure mine are stainless so there's no problems with rust. I have installed them with some very thin stainless flat washers between them and the stainless bosses on my Nomad, only because I didn't want to ruck up or mar the powdercoat on the BB shell posts.

Hope this helps, apologies for the late reply, Dan.