Shaving off bronze bow roller

[LifesBetterWhenYoureBeating]

Hi everyone,

I have this big bronze disc (is it the roller or is the roller the whole thing?) on my bow roller but unfortunately the walls of the roller have been pushed towards each other in some parts so the disc rubs against them and barely turns. I'm not comfortable trying to unbend the walls as my headstay is attached to it, so I thought I'd try to shave off some of the bronze disc to fit a washer between it and the walls. I got myself some 60-grit sandpaper (the most Coarse I could find here) and a sheet sander, but after sanding and replacing the sheet 8 times, I haven't made much progress. Is there anything else I could try, or are more sheets and patience my only option?

Thanks in advance!

[Kettlewell]

I have this big bronze disc (is it the roller or is the roller the whole thing?) on my bow roller but unfortunately the walls of the roller have been pushed towards each other in some parts so the disc rubs against them and barely turns. I'm not comfortable trying to unbend the walls as my headstay is attached to it,

Would make me a bit worried that the headstay attachment point is too weak for the job. I suspect the best way to shave down the bronze disk would be to take it to a metal shop that could use a big lathe to trim off a bit. OTOH, would you consider switching to a plastic roller? Quieter, doesn't take off the galvanizing on the chain, and easier to find than trimming the bronze roller down.

[JBP]

If you are confident about the headstay attachment then in decreasing order of aggressiveness:

Angle grinder
Belt sander
Rotary sander (not orbital)
Orbital sander
Sheet sander.

[Joh.Ghurt]

Check for the closest workshop with a lathe. They can turn it down for you to the exact size rather quickly. And if you go to the corner mom&pop-shop, it's probably not that expensive either.

[TrentePieds]

No sense in messing about with sandpaper. Bronze is MEANT to resist abrasion. that's why we pay big bux for it, and why the blanks for things such as this roller are made in brass foundries and finished in machine shops.

Take your roller to a jobbing machine shop. They will chuck it up in a lathe and turn it to your specs. Once the roller is chucked, the turning will take about thirty seconds.

When turning, leave a shoulder around the spindle 'ole at the existing thickness of the roller.

TrntePieds

[boatpoker]

I know of three local machine shops in my neighborhood that would charge $20 to turn that down for you. I'm sure you could find one.

[Bellinghamster]

As stated above, a lathe would make quick work of it, but I'd be much more concerned about why the opening it fits in has become narrower. If that is what is holding your headstay down, that needs to be addressed because something is moving that shoudn't be.
Can you post a pic of the bowsprit assembly showing where the roller goes, where the headstay attaches, and of the bobstay, gusset or whatever (if present) is countering the upward pull of the forestay?.

[capt jgw]

Do you know how or why the sides got deformed? It could be the force from the headstay proving that it's not strong enough. Trimming the roller could just give it room to deform some more, repeating the problem.

[LifesBetterWhenYoureBeating]

Originally Posted by Kettlewell

Would make me a bit worried that the headstay attachment point is too weak for the job. I suspect the best way to shave down the bronze disk would be to take it to a metal shop that could use a big lathe to trim off a bit. OTOH, would you consider switching to a plastic roller? Quieter, doesn't take off the galvanizing on the chain, and easier to find than trimming the bronze roller down.

Attached are a couple photos of the bow roller (with a plastic roller I put in place while I worked on the bronze one) and the attachment point for the headstay. The deformation I meant would be imperceptible if it wasn't for the fact that the roller fits snuggly there. Do you think there's any reason to believe this could be compromised as an attachment point to the headstay?

As you see above, I already had a plastic roller (doesn't seem to be in great shape as it has probably been sitting in the sun for ages), but I *assumed* the bronze one would be superior. However, just the mention of it being more gentle on the galvanizing has convinced me to give up on the bronze roller - - I'll just order a new plastic one and keep the old as spare.

Thanks for the suggestion!

[Kettlewell]

I doubt that your headstay tension is causing the sides of the roller to move inwards. Instead, I would suspect first just some corrosion between the bronze and the stainless causing binding. Or, there is a possibility the roller got bumped in a docking situation or by another boat. I have seen lots of bent rollers as a result of collisions with stuff.

[LifesBetterWhenYoureBeating]

Originally Posted by Bellinghamster

As stated above, a lathe would make quick work of it, but I'd be much more concerned about why the opening it fits in has become narrower. If that is what is holding your headstay down, that needs to be addressed because something is moving that shoudn't be.
Can you post a pic of the bowsprit assembly showing where the roller goes, where the headstay attaches, and of the bobstay, gusset or whatever (if present) is countering the upward pull of the forestay?.

I've posted a couple photos above. It's not like the whole length of the wall was deformed, it's more like it was hit with something or someone overtightened the nut on the bolt that goes through the roller - - the plastic roller is fit with a regular bolt and a nut (which I intend to replace with a rod with untightened nuts secured by one locking pin going through the nut and the bolt on each end, like I had on the bronze roller)

[LifesBetterWhenYoureBeating]

Originally Posted by Kettlewell

I doubt that your headstay tension is causing the sides of the roller to move inwards. Instead, I would suspect first just some corrosion between the bronze and the stainless causing binding. Or, there is a possibility the roller got bumped in a docking situation or by another boat. I have seen lots of bent rollers as a result of collisions with stuff.

A collision or someone overtightening the nut on the roller was my guess as well

[Polar Opposite]

Where are you located? I'd be happy to skim it for you in my shop lathe. Drop by in Florida, or cover the postage. 20 min job.

[Kettlewell]

I never understood bronze anchor rollers. Won't there be a galvanic action problem between the bronze and the galvanized chain in he presence of seawater? In any case, they transmit the noise of the chain into the boat quite effectively.

[stormalong]

It is very easy to spread the two plates apart a little bit.

1) Get the largest diameter threaded rod that will go in the roller hole plus two nuts and washers to match.
2) Put the rod through the hole. Thread on the washers and nuts in the gap with the washers against the plates.
3) With two wrenches tighten the nuts against the plates to spread the gap a bit.

Easy peasy you are done.