Mainsheet ratchet & blocks

[Jaycb]

I've spent some time over the weekend cleaning the mainsheet ratchet & blocks on my Dart. I took some photos beforehand to ensure I put it all back together properly but I'm not convinced it was assembled right in the first place. I can't refer to the manual because apart from the ratchet it all looks like non-standard stuff (it's made by RWO).
Does anyone know if it's possible to post images on this site, or is anyone who thinks they can help prepared to allow me to mail them a photo of how mine's all attached please? I could do with some advice.
Also, I've no idea how the mainsheet is meant to be threaded through this system...

[Erling]

Hi Jaycb
If you send it to me at (erling@holmbergtrading.co.uk) I will try to help.

[Bob Carter]

Hi Jas
Have a look on this website.
Look under:
Manuals/Rigging Manual
And then select P19 and print it off.
This is the picture that you require.
Cheers
Bob

[George Love]

Hi Jacyb,
In the last issue of the Class Magazine 'Newsprint', there was a good 'tips' article about mainsheets with photo. Did you see my response to your posting about dents and scrapes etc. in which I asked if you had had, as a new member, a copy of the Mag? As I in that posting, if you e-mail me your postal details, I'll send you a copy. Contact me at: newsletter@sprint15.com
Cheers,
George (Ed.)

[Charles]

Jaycb

I think you might have the old style blocks. Mine are RWO & look rather different to the newer black, solid block arrangement, but work perfectly well. I've sent Erling some pictures so he can compare & send on to you if you want.

Charles.

[Jaycb]

Thanks Charles. I sent Erling some photos of mine last night - I'll let you know what he thinks.
J.

[Robert]

Hi Jaycb

I have the same blocks as Charles and I threaded them using the picture that Bob Carter suggested. If you follow it closely I think you will find that it works OK. After testing I made one minor alteration to the threading so there is slightly less contact between ropes when the system is pulled nearly all the way in but it works well both ways (mine and the one in the picture).

Robert

[Jaycb]

Thanks robert. The problem is that the picture Bob suggested shows four of the RWO "blocks" in the setup, whereas I've only got two, plus the ratchet/cleat bit. I was playing around with it this morning and reckon I've got something that'll work, but I don't know if it's strictly correct.

[Charles]

Jaycb

I think very old boats did originally have fewer blocks & therefore less purchase, but if you want to sail in any sort of wind you'll need the 8:1 set up.

[Bob Carter]

Hi Jas
The picture is correct - you should have the inner blocks as well. That makes the system a 7:1 ratio. You need to buy some extra parts to get the full system working properly.
Regards
Bob
PS Some of the earlier boats (Spark Funs) were sold in non racing format without cocktail cabinets and without all the pulleys on the mainsheet assembly. I think that you have boat #1216 which was a 1988 Dart 15 and not one of the earlier Spark Funs. Someone must have taken off and lost the inner blocks of the mainsheet assembly.

[Jaycb]

Ok, seems like we've got to the bottom of this one. Thanks everyone. I'll probably stick with the two blocks for now and maybe pick some up cheap at the show in March. I'll probably only be sailing the boat in non-windsurfable weather so shouldn't be a problem.

[Bob Carter]

Hi Jas
This could be a cheap way to get your extra blocks. This Dart 18 system on EBay is the same as the old Dart 15s but with a longer mainsheet


http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :IT&ih=008

Cheers
Bob

[Charles]

Jas

I've had a look at mine & both pulleys are the same, with one just having an additional long shackle, with the clevis pin through the centre of the block, this creates the place to dead-end the sheet.

The max dia of the sheave seemed to be 43mm.

Looking on http://www.rwo-marine.com/ I guess the nearest is the current 45 series, though these say designed for max 10mm rope, where as theoretically the Sprint is spec'd for 12mm.

The 57 series says it takes 12mm, but those sheaves are loads bigger than what I have on.

Also the current models are a slightly different design to mine.

Think you should go for R4701 & R4702. I don't think you should go for the ball bearing races, on the basis that mine aren't, though the solid black "new" type blocks are.

Does anyone know if the old pulleys can be legally replaced by RWO ball bearing blocks?

[Andrew Hannah]

I'd like to pose a question on this thread.

The mainsheet pulley system on my Sprint, has the more modern pulley system with black plastic blocks and white wheels. The mainsheet I use, is a thick rope which is slow to run-off when eased in gusts, or when starting the downwind leg.

I tried a thinner diameter rope (supplied by a respected source!). The standing end of the sheet kept on jumping out of the block. I re-tightnened the small bolts that are set into the blocks, but to no avail. When under load, the sheet jumped out again. So, I have reverted to my thicker main sheet.

I wonder if anybody else has experienced this. If so, what was the remedy?

[Robin Newbold]

You could try wrapping whipping twine around the end to make it thicker, or something like that. I haven't tried it, as i've got ye olde blocks, but i'm sure someone has done it before