Broken sheaves

including Amas (Floats), Akas (Beams) , Swing Wing system and all other hull related issues.
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Mika Harju
Posts: 218
Joined: Thu 02 Nov 06, 13:19
Your Country: Finland, Turku

Broken sheaves

Post by Mika Harju »

Any ideas how to remove the sheave box located at the fixed end (on hull) of right aka? These ropes controls amas in / out function (white ropes with black/blue dots).
I could not find a way to reach this installation from inside and there are no screws outside.
How about left side, do I need to remove the fridge to get there?
:(
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Mika Harju
DF1000 Racing #8
Mika Harju
Posts: 218
Joined: Thu 02 Nov 06, 13:19
Your Country: Finland, Turku

Re: Broken sheaves

Post by Mika Harju »

Here is answer from Quorning Boats:
Unfortunately, it is very difficult to change these double blocks, as, in order to make it watertight inside the cabin, we have laminated a plastic tube to the boat, so there is no direct access, unless you cut away the plastic tube, change the block and laminate again. It is also difficult getting access to behind the blocks.
The price for these blocs is EUR 85.- each excl VAT. We have a stronger version which cost EUR 95.- each excl VAT – we have these on stock.
On the right side of the boat, this block is behind the galley area, and I am afraid that you have to cut away the vertical wooden plate behind the galley under the upper shelf by the cabin side.
------
Then I asked if it possible to cut it off from outside and replace it one equipped with a flange.
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Yes, maybe it is possible, what you say, but the problem is to make it strong enough, as the load on the block goes out (not in).
As an alternative, my best gues is to maybe cut out the block, as you say, and then install the new block on a plate that is screwed and glued on with epoxy as well – using a fibreglass plate, which we can also supply to you. But – I cannot give you any guarantee that it will work 100 %, I think it will.
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We have these special sheave boxes with special PETP (Delrin type) wheels only, but we do have a stronger model.
To make this plate with a double sheave box will cost EUR 200.- for each side, incl sheave box but excl VAT, ex works. This plate has to be glued and screwed in place. Please note though that we cannot give any guarantee that this will work, as we have not made this before. I do believe it will though.
The difficult part is to get out the old sheave box.
Time of delivery is approx 3 to 4 weeks upon receipt of order.
Mika Harju
DF1000 Racing #8
parkhouse
Posts: 32
Joined: Sun 20 Jul 08, 17:56
Your Country: U.K./Inverkeithing

Broken sheaves

Post by parkhouse »

Both out line sheaves in the coaming double blocks (i.e. where the lines are directed to the winch) are cracked and partly broken. I asked Quorning for advice and this is their reply:-
"The double sheave box is beefed up to a slightly bigger size from 10mm
sheaves to 12mm.
You need to cut or file the holes a bit bigger for the new model which
also is more durable.
One double sheave box costs 65 euro +VAT and shipping."

Mika - how did you end up solving your broken sheaves problem?

Mike Paterson, Champus
Mika Harju
Posts: 218
Joined: Thu 02 Nov 06, 13:19
Your Country: Finland, Turku

Re: Broken sheaves

Post by Mika Harju »

parkhouse wrote:Both out line sheaves in the coaming double blocks (i.e. where the lines are directed to the winch) are cracked and partly broken. I asked Quorning for advice and this is their reply:-
"The double sheave box is beefed up to a slightly bigger size from 10mm
sheaves to 12mm.
You need to cut or file the holes a bit bigger for the new model which
also is more durable.
One double sheave box costs 65 euro +VAT and shipping."

Mika - how did you end up solving your broken sheaves problem?

Mike Paterson, Champus
I have not yet made this task because my sheaves are not totally broken, this seems to be quite a big and difficult job and I am still able to operate the SwingWing system. I should finish this task, because I know some day the sheaves will broke into pieces.
If you can find a good solution how to install the new sheaves, please let me know.[/quote]
Mika Harju
DF1000 Racing #8
Double Horizon
Posts: 440
Joined: Wed 09 May 07, 0:18
Your Country: USA

Re: Broken sheaves

Post by Double Horizon »

Mika the good news is you have had the issue for two years and it is still functional.

I would follow Quorning's first instructions and go through the galley. A vertical wood cover panel is easily replaced because it is only cosmetic, not structural. Start with a small hole so you can see how much wood you need to cut, then make it larger as-needed. You can buy thin teak veneer at any good furniture lumber supplier. Dry-fit the wood carefully and apply finish before gluing. You might need to add thin trim strips to cover your edge seams. You could also substitute another panel material like black Plexiglas, or black or white laminate for your cover.

(I put a new veneer on the teak salon table in my 1000 and it took a long time to dry-fit the veneer to exactly fit the curves of the raised edge all the way around, but after the initial rough-cut I was using sandpaper on a wood backing block to shape the edges until it fit exactly. After gluing I used 7 coats of semi-gloss varnish, sanding between coats with 220-grit paper. It came out beautifully.)

It will take time but you will be proud when finished.
Larry - Former Owner DF-1200
Oscar
Posts: 148
Joined: Tue 26 Aug 08, 23:10
Your Country: USA, North East

Post by Oscar »

The price for these blocs is EUR 85.- each excl VAT. We have a stronger version which cost EUR 95.- each excl VAT – we have these on stock.
Why would one even stock/install an inferior block for such a hard to replace installation? For a EUR10 savings? :shock: Hey, I'm Dutch and ready to save a buck where I can, but that sounds silly!
1990 Dragonfly 25 USA-54
Tuca
Posts: 23
Joined: Sun 03 Feb 19, 23:48
Your Country: Spain, Sevilla

Post by Tuca »

I have already made this reparation myself on starboard side.

I did made the reparation last summer, before reading this post, but have been made exactly as Quarning details in last post.

I did broken a litte wood and fiber glass from 2 of the 4 sides to extract the sheave.

After that I did desing in Autocad and cut with CNC a 5mm fiber glass plate with lot of holes. The sheave screw to inside this plate and the plate screw with lot of holes to the glas fiber wood on Dragonfly. No need for epoxy and working great for 3 months.

If anybody need the Autocad desing or pictures you can PM me and I will share.
Eladio -- DF 1000 #29 "Tuca"
jms
Posts: 2
Joined: Tue 08 Aug 23, 3:12
Your Country: usa
Sailing Area: salish sea

Re: Broken sheaves

Post by jms »

This is great information for someone is hoping to do this project shortly on a df1200.

Hi Tuca,
I don't see a way to PM a specific user in this forum. I'd appreciate if you could send pictures and CAD drawings.
Thanks.
jmsurfer2000 @ yahoo . com
crackersrevelation
Posts: 1
Joined: Thu 14 Sep 23, 15:24
Your Country: United states
Sailing Area: Alaska

Re: Broken sheaves

Post by crackersrevelation »

To remove the sheave box on the fixed end of the right aka, try checking for hidden screws or bolts beneath any coverings. For the left side, removing the fridge might provide access, but inspect carefully before doing so. Good luck!
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