My boat is ashore and looking up from below there are two rollers in the keel box at the forward end of the keel which appear to be mounted in a plastic block held in by two large set screws.

One of the rollers (the lower) appears to have jammed at some time in the past and has a flat on it which is preventing rolling during keel lifting.

If anyone has ever taken this assembly apart or had a similar problem I would be keen to hear how you overcame the problem - or did you just put up with it?javascript:__doPostBack('forum$ctl03$PostReply','')

http://www.parkerseal.or....aspx?g=posts&t=1405 

That roller is now a little grooved, so I'll be replacing the roller again this winter. With my previous modifications replacement of the roller is quite easy. The roller comes under quite high load in the last part of the keel travel, and with the limited space to fit a larger roller it is always going to be prone to this problem.

Your description suggests that your roller system is somewhat different, do you have any photos of it? I'm very interested in potential improvements to this part of the system.

Is your boat a 27 or 275? The 27 has a ballasted keel that weighs around 100kg, the 275 & 285 have cast iron keels that weigh around 320kg. The loadings on the lower roller will be significantly higher on the 275/285.

Jake

Jake

I was at the boat yesterday so took the attached photo (hope I got the upload right and it is available to you).

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Hadn't seen one like that before - we have a few 27's at the sailing club so I'll see if they can have a look at your thread on the forum.

Regards

Have you had any feedback from the 27's at your club re the forward rollers (or not)?

Also the two up haul sheaves (see photo 4 - taken from port looking to starboard i.e. forward to the left) appear to be completely individual i.e. one is aluminium and one Tufnol, of differing diameters and widths and their mounts are only similar.

Can anyone enlighten me as to which is the repair? I intend to have the keel lifted out and to undertake dome refurbishment. Would P27 owners like me to document my activities for the forum/articles section?

My thanks to those who have already assisted in this thread.

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https://www.dropbox.com/...zuB3Asx01wXAQ4L4e6a?dl=0 

It looks like he just has acetal buffers at the front and back of the keel. I don't think he has the rollers inset into the front and back top of the keel. I think there is a roller mounted between the acetal guides at the aft top of the keel.

Regards

Dick

Many thanks for uploading the photos. Please give my thanks to Chris Nichols.The arrangement looks some what different to mine. I am going to have my keel lifted out this week in order to refurbish

the rollers and the lifting sheaves. I may also introduce two additional sheaves to form an 8:1 advantage as I think I should be able to pull this by hand having tested this by putting a 2:1 on the hauling line of the current 4:1 arrangement. It was easy to haul be hand.

I will also try to remove the forward lower roller fitting and will post my results.

The photos of Chris Nichols look as if the acetate bump stops are new. If so where did he get them made or was it a home job?

I would be interested see photos of the top of Chris Nichols keel if he feels he can oblige.

P.S. Do you know if Parkers are still contactable and if they might be able to help. It looks like the P27 keel arrangement may have gone through an evolution process.

I replaced the aft buffer on Dark Star, I made the buffer from a 20mm thick piece of Acetal. I used a profile gauge, bevel gauge, and templates to get the shape of the recess it fits into, and the geometry of the keel trailing edge. Rather a slow process, but ultimately successful.

I'll see if Chris can join this thread.

Regards

Dick

as DickG says I have a P27 - and have just fitted two new 'bearing blocks' at the fore and aft end of the keel slot. I actually used solid PTFE just to see if it aided in reducing friction and to assess its lifetime - it seems quite soft compared with nylon (and more expensive) I have two nylon blocks ready to put in it the PTFE fails.

Regarding the rest of my keel set up, I have fitted a second wheel inside the keel (very similar to pictures shown above) and a second stand up block on top of the keel box cover. Keel pull-up rope is dead-eyed on top of the keel box, then goes to wheel 1 in the keel, up to the other keel box top block and down again to keel wheel 2, returning to the keel top block 2 and away to the guide blocks and deck organisers. I have paid much attention to the actual routes taken by the keel rope - making sure all the entries and exits to the blocks are straight in and straight out - no touching of any sheave edges or such like. It is staggering how much friction is increased by even a slight touch on an edge. The main places to check this are the three holes (actually long slots) in the keel box top. The angle of the rope between the keel block and top blocks changes slightly as the keel goes up and down, so the fore and aft movement of the rope must be accommodated by these slots. Similarly the deck organiser blocks must have the rope feed-line into them such that there is no touching on the frame that contains the organisers - mine originally touched the top aluminium plate and then ran on the top of the wheel causing the aluminium to wear and the wheel to chip on the top edge.

To get this alignment correctly adjusted, the block at the aft end of the keel box cover has been moved to an eye fixed to the mast step which raised the block and gives a straight lead from the 'out' block on the keel box top and leads straight and square into the deck organiser.

With all this done, I can pull the keel up from the cockpit without using a winch - just!, although my wife cannot - and we normally use a winch when sailing as the sideways forces increase as the hull may well be going sideways.

A check can be done to see where friction is occuring if you try to pull the keel up by hand using the rope between the deck organiser and the block at the aft end of the keel box. This will also prove if the swivel on this block is articulating sufficiently.

After all this, mud is still our main enemy here on the East Coast - the boat in on a drying mooring and if not used for 10 days mud oozes up into the keel box and makes things difficult. To cope with this I have enlarged the hole in the centre of the keel box cover so a large funnel can be used to pour buckets of water in from the top - which helps lubricate the box and slurrify the mud, which can usually be cleared after a couple of hours sailing. I have tried general purpose grease, McLube, PTFE food grade spray, and water proof grease, to aid the friction problem - all did little after initial application and the grease was worst of all as formed the stickest substance known to man when churned up with mud and salt water - and took a lot of cleaning out. I now keep the box clean of all lubricants except sea water. I will get some shots of the deck top bits asap.

Rgds

Chris

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Many thanks for your reply. I will check all the tolerances before I get the keel removed. The PTFE is likely o be softer than the Acetate/Nylon of the original fit so may wear more quickly even though more slippery.

I will also try your check of raising the keel at the mast. My keel box is quite clean (no grease) so it should be a good comparison.

Thanks in anticipation for the extra pics. Having looked at many P27s for sale on the internet some have two blocks and some only one, so it looks as though mine was and your now is modified.

My keel cover has aluminium cheeks where the retaining pin goes through and an aluminium angle at the aft end to locate the cover agains the mast end face. In addition there is an aluminium reinforcing beneath the turning blocks.

One more quick thought - i use 10mm keel hoist rope so it minimises chance of rubbing anywhere.

Rgds

chris

Chris

FWIW I checked and there are no rollers or additional bearing bits at the bottom of the slot beyond the two nylon pads fitted flush with the hull.

The pics show a block fixed with string at the top which is approx where it needs to be to give the best feed angle from the top of the keel box and on to the deck organiser. This is normally fixed to a loop on the mast which gives the height needed.

The large hole is used to lubricate and flush the box when mud gets up inside - this hole is right size for a v. large funnel to fit in so a bucket can be used to pour seawater down.

All three holes in the keel box top which the keel rope runs through are slots (see last picture) - as the angle of the rope changes as the keel rises and falls. If the rope touches the side of a hole you can see a little wear where it touches - file this away!

The plastic cover over the top blocks stops the jib sheets getting stuck. Pictures 1 and 3 also show the keel 'restraint' wire (which is also used to lift the keel out) and the red rubber 'dog kong' shock absorber just catches the keel as it bottoms, preventing a 'hard' drop. The top of the keel box cover has been reinforced to take this extra loading.

Rgds

Chris

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Great information. Many thanks. Your boat looks in fine fettle. Do you know what pulleys are actually in the keel?

It is interesting that your turning blocks are Barton blocks. Mine are tufnol, 50mm dia. and have the name Main etched on them.

For your interest I have attached some photos of my bits and pieces plus views inside the keel. The picture of the keel and bits shows the top of the keel with lower roller block upside down wight he removed rollers in front of it. The front wear pad is to its right (also inverted). the two pulley blocks are those removed from the slots in the keel. I believe the tufnol one may not have been an original fit.

My cover is also reinforced with what appear to be brass plates through the centre section where the lifting blocks attach and also under the aft aluminium plate (only half in the picture. it has a location tang that fits down the aft end of the keel box to take the load off of the four cover corner fastenings.

The two pictures of the inside the keel show the view from above without the keel but with the forward rollers in place and the other is a view looking forward wight eh keel roller block and wear pad removed.

The last is a general picture of the removed keel, the tape is laid on a red china graph line (just visible above the tape. This line was found by balancing the keel on two short rollers, one under each end.

It's my attempt to get a GC line.

One of my tufnol rollers was seized to the space so this was creating additional friction. I'm having this rebuilt. I will be getting the keel home today so I can work on it in my garage.

I am considering turning the system into a 6:1 by moving on of the cover blocks forward and adding another aft. This will nee the keel to have a third or large hole cut to accommodate the additional pulley. At present I'm still thinking it though but I will let you know what I do in case you have similar naff rollers in the keel and have to replace them at a later date.

Lastly please can you let me know what is the size of the Barton cover turning blocks (4, 5 or 6)?

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