Replacing reefing line sheeves on a 1983 Beneteau First 38

[JuanMarcos]

I have an 1983 First 38 and after a close inspection this past weekend, I realized that the reefing line sheaves in the boom end are starting to shatter. It would appear that all sheaves, including the one for the outhaul will need to be replaced.

Does anyone know what that would entail for my particular year/model boat? Does the boom end need to come off? (I did not see any screws holding it in place). Does anyone know what size of sheeve I would need to use, and whether the axle may be worth replacing as well?

Your thoughts and/or experiences are highly valued. Thanks!

 

[Michael Davis]

Just went through a survey this week and was told it's getting close to the time to do mine as well ( 1984 First 38 ). He also said if the ones down here are getting worn I should look at the ones on top of the mast as well. I'll be down at the boat today to see how i can tackle it. Never bored with nothing to do when you own a boat!

 

[sailme88]

Selden mast and boom ? If so, they'd be your source...Info and parts that is

 

[Michael Davis]

Selden mast and boom ?

I believe it's Isomat but will check this morning

 

[JuanMarcos]

Isomat.

Good point on checking the masthead.

 

[APP314]

Hi Marcos,
If memory serves, for the boom end they used the same system as for the masthead, that is the sheaves are mounted on a common axel that slides on a V shape groove from the open end of the the sheave box. I dealt with the masthead a few moths back, and ended up making custom sheaves as nothing I could find felt acceptable. I documented my process here
Restoring Canis: Episode 2

Gerhauer makes sheaves of the right width, but the finishing was disappointing and the edges had often sharp edges sure to damage the lines. I used bronze bushings but I think that is a bit of an overkill, a machine shop should be able to make custom sheaves at a reasonable cost. Alternative Zephyrwerks makes custom sheaves I think they make a superb product (although a bit pricey).
All the best,
Alejandro
Alejandro

 

[Michael Davis]

the sheaves are mounted on a common axel that slides on a V shape groove

That's what I found this morning. Once the outhaul and reefing lines are pulled out of the way(not removed, just pulled aside) the axel with sheaves just pop out. Aft end straight back and the fore end vertically up.

 

[heritage]

Great video, Alejandro!

 

[Doug in Lakeview]

Hi JuanMarcos,

The 1980’s Beneteau First 38 rigs were manufactured by ISOMAT. Unfortunately, ISOMAT is no longer in business. They had a large market share and thus a few vendors still carry parts. RIG-RITE (located in Rhode Island) carries many parts for these masts. www.rigrite.com

I have ordered parts from them twice and have been very pleased. It is best that you consult their website first to determine which specific parts you need. My experience has been that if you are able to specify the part number & description for the part that you need, they will have it to you within a week or two.

We have replaced the sheaves at the top of the mast, bottom of the mast, and both ends of the boom within the past several years.

While you can measure old sheaves with a caliper I wanted to go a bit farther. I have an ISOMAT catalog from the 1980’s and was able to determine the model number/part number of the equipment installed on our First 38. We have the keel stepped tall mast. Yours may be different. By using the ISOMAT catalog, Rig-Rites’ website, and my measurements I was able to determine the parts that I needed.

ISOMAT catalog is attached as a PDF file. Highlighted items are for my First 38.

 

[jssailem]

I used Zephyrwerks for one of the masthead sheaves that needed to be replaced on Hadley. Excellent product.

 

[JuanMarcos]

That's what I found this morning. Once the outhaul and reefing lines are pulled out of the way(not removed, just pulled aside) the axel with sheaves just pop out. Aft end straight back and the fore end vertically up.

Can you elaborate on "aft end straight back and the fore end vertically up"? I want to make sure I get this right...

 

[Michael Davis]

Can you elaborate

There is a slot in the end-cap casting that accepts the axel and sheaves. Once the reefing lines are out of the way I used a screw driver to give a little pry and it popped right out. We've got a full canvas cover so I had the boom pulled to one side, was surprised at how easy the parts came out and almost lost them over the side. The mast end is the same system and was a little harder to get out. Used a long punch and a small hammer. Everything is held together by the tension of the reefing lines and outhaul. It's pretty easy to see once the lines have been loosened and moved out of the way. Hope that helps.

 

[JuanMarcos]

Thank you very much. I will definitely check it out, and hope it's as obvious to me as it was to you.

 

[Michael Davis]

If you're like me you worry that it will be harder than it is. I was surprised at how easy and straight forward it was. So easy I almost dropped it overboard!

 

[JuanMarcos]

I wanted to thank you all for the amazing feedback. This weekend I was able to easily get the sheeves off thanks to Michael's advice, and will now try to get replacement parts through either Rigrite or Zephyr on the basis of the extremely valuable catalog that Doug provided.

When in doubt of whether to put in the time to answer to blog posts, please remember that there are newbs out there like myself for whom your generous advice is priceless.

 

[JuanMarcos]

UPDATE: I checked Rigrite as Doug suggested (thank you Doug for the catalogue). The price for each sheave was around $50 plus S&H. Instead, I reached out to a manufacturer in China that custom milled the sheaves in aluminum for a fraction of the cost, and since I was at it, I had them make the sheaves for the top and bottom of the mast.
The quality of the material looks very good. I will send an update on how the sheaves continue to perform.
If anybody is interested, message me and I will send you the information for the fabricator I used.
So now I am going to change the outhaul and reefing lines. Any recommendation as to the type and girth of the rope to use for that purpose? Is anybody running any of those lines to the cockpit? If so, how/where?

 

[JuanMarcos]

So, after the success with the sheaves for the outhaul and reef lines, I am moving on to the fairleads and the main traveler (which does not allow the car to "travel" very easily anymore).

Does anybody know the specifications (diameter, thickness, etc)? I believe these are Goiot. Any chance someone might have a catalogue like the one Doug had for the Isomat spars?

 

[Mechone]

I made my ones the same way as in the video out of delrin, the problem making them out of aluminum is that unless the aluminum sheave is sent out for anodizing (hardening ) they will not last , installing a bronze bushing will extend life and even with that anodizing only hardens in a couple of thousands of an inch, once you wear thru that its toast. Not sure of size however ,US spars makes a 60mm delrin ball bearing sheave 15mm wide for 28.00

 

[JuanMarcos]

So those are the dimensions? 60mm external diameter and 15mm wide? What about the diameter and depth of the groove and the inner hole for the screw?

 

[JuanMarcos]

Yesterday I checked the sheaves on the fairleads. They are made of aluminum and have very little corrosion so I will probably polish them up, lube and re-install.

About that I have 1 questions for anyone familiar with this hardware:

1) After brushing with a wire brush, how should I polish aluminum sheaves?
2) How should I lubricate the space between the bushings and the sheaves?
3) I took one of the sheaves out, which was pretty straightforward. However, when I re-installed it, the screw would not stop turning. I fear there may be a nut underneath that I am now not engaging. Does anybody know why the screw is not stopping, and whether I will now have to pull the headliner to fix that from underneath?