Another Kemp Boom Question

[sgr143]

Having had trouble with my outhaul being very stiff (pretty much immovable), I tried to remove it, with the aim of maybe replacing it with dyneema. I should have found and read this thread first!
I had foolishly assumed that the wire feeding in at the aft end of the boom just attached directly to the rope exiting at the gooseneck end (like the wire+rope jib halyard I replaced some while back). I didn't realise there was tackle and car inside the boom itself! No wonder I couldn't get it out with a simple pull from the aft end (with mousing line attached to the rope end of the outhaul). It all got jammed up, which I put down to the internal runs of the reefing lines getting crossed over the outhaul line. Now I can't move it either way, and I don't want to pull too hard on the sewn-on mousing line in case I pull it away from the end of the outhaul, the junction now being inside the boom.
I have just (today) brought the boom back home so I can work on it in the relative comfort of my garage. I hope all will be clear and possible to sort out once I've got the end castings off. Any hints and tips would be greatly appreciated.
Thanks, Steve

 

[adamlang]

I've not sorted out ours yet. We're having some fibreglass work done in the cockpit and the person doing it is going to use the boom to support a tent/ cover.

Since we took the mail sail off though the clew car (if that's what its called) has slackened off and has a little give it in now. Still not sure what to expect inside but I imagine cleaning everything, some grease on the bearings of the blocks, and replacing the very old outhaul line, which is probably spliced into something.

I think I've ruled out dyneema as I'll want the thickness to handle the outhaul line. No winches on our setup. The strength of such a line will be plenty.

I'll take the opportunity to rince out the boom, expecting lots of crap which can't be good for the lines.

Are your ends secured with bolts or rivets? Our aft end is bolts but the forward end is the original rivets. Thinking that i'll tap some threads and replace with bolts.

Isn't the nack of drilling the rivets getting the speed right?

 

[sgr143]

I was thinking of dyneema to replace the wire that hitches the tackle inside teh boom to the clew car, not the outhaul line, which I now find (I think) is a separate thing working the tackle..

Rivets both ends but I will tap the holes when I've drilled them out and replace with bolts.

 

[William_H]

Having had trouble with my outhaul being very stiff (pretty much immovable), I tried to remove it, with the aim of maybe replacing it with dyneema. I should have found and read this thread first!
I had foolishly assumed that the wire feeding in at the aft end of the boom just attached directly to the rope exiting at the gooseneck end (like the wire+rope jib halyard I replaced some while back). I didn't realise there was tackle and car inside the boom itself! No wonder I couldn't get it out with a simple pull from the aft end (with mousing line attached to the rope end of the outhaul). It all got jammed up, which I put down to the internal runs of the reefing lines getting crossed over the outhaul line. Now I can't move it either way, and I don't want to pull too hard on the sewn-on mousing line in case I pull it away from the end of the outhaul, the junction now being inside the boom.
I have just (today) brought the boom back home so I can work on it in the relative comfort of my garage. I hope all will be clear and possible to sort out once I've got the end castings off. Any hints and tips would be greatly appreciated.
Thanks, Steve

Taking the end cap of can be very difficult. You might take note if you can afford to lose some length of the boom because you may end up cutting off the boom at the fitting. That is after trying hot water etc to try to break the corrosion.
The fitting will fit into the boom by perhaps 3 or 4 cms You could try cutting the boom about half way along ie 2cms in from the fitting with a hack saw. Try to cut at an angle so you can destroy this ring of boom and can get under the cut edge to lever up and off. Once you have removed this ring of boom material near the fitting you may be able to move the fitting in the remaining boom. Try abshing the fitting in further with a carefully calibrated bashometer. (lump hammer)
All very horrible but necessary for maintenance, refit with lots of duralac or grease. ol'will

 

[sgr143]

Taking the end cap of can be very difficult. .... All very horrible but necessary for maintenance, refit with lots of duralac or grease. ol'will

Thanks Will! But actually the clew-end fitting came off very easily once I'd properly drilled out the rivets, using a 5mm drill so I can later tap the casting for 6mm bolts.

Unfortunately I think I've got a real problem now. Looking into the now-open end of the boom, I can see the end of the outhaul tackle about 1.5m down, totally jammed in. It looks like it has some of the outhaul line wrapped under or around it. Luckily the reefing lines seems to have escaped this entanglement and run free. I've tried shoving and thumping it with the end of a wooden broom handle. It doesn't shift.

I guess the next stage is to take the gooseneck end fitting off as well and see what can be done. But the jammed tackle is much nearer the clew end. At least then I can take the reefing lines out altogether (and be able later to put them back in, using electricians' fibreglass wire-poking poles) so they are not going to get in the way or get damaged by any violence I try on the outhaul tackle. Copper pipe and a lump hammer?

Oh dear. Just goes to show. Assume nothing and go looking on the web for and read the manual first. A bit late now.

Steve

 

[sgr143]

For anyone still following this saga, I'm pleased to be able to report that I got the end-caps off the boom without too much difficulty, and have freed and extracted the fiddle block that was jammed. I can can now clean and generally sort out the various sheaves, lines, cars and sliders so it will I hope work a lot more smoothly. Reassembly shouldn't be too difficult, and I have learnt a bit more about how things work on the boat. So I'll call that a positive outcome. Thanks all for the various bits of advice. Steve

 

[adamlang]

I'm happy to report some progress as well. Finally managed to get the boom home and the ends off. One final question at the end. It turns out I had 5:1 purchase for the outhaul using two double blocks. One had snapped, and the other is seized with rust - Seasure blocks, I'll not be using them again.


Also maybe worth mentioning that on my boom, there's an internal car that the clew attaches to. Needs some replacement clips and maybe some new wheels. Two of the wheels feel right off due to a missing clip, but they are captive in the boom track.


Anyway, I'll be giving it a thorough clean, and replacing some very worn sheaves, and tapping some new threads on the gooseneck end.

When I put the ends back in, what should I use to stop corrosion between the ends and the aluminum boom, and on the bolts, and to ensure it all comes off easily next time i have to take it apart?

Thanks.

 

[William_H]

Duralac is the old remedy for corrosion between different metals. However there are more modern cleaner equivalents. Good old axle grease will go a long way to helping.
I must say on m y 21 fter with relatively large main sail I use a straight outhaul rope with 2 to 1 purchase at the clew eyelet going down from gooseneck to deck and back to halyard winch. Only straight rope inside boom. With a sheave in a box at boom end and at gooseneck. Also similar line inside boom for one reef.
I do not have a track on boom top for foot (loose foot sail) and 2 sided velcro or just rope to lash clew down to boom. Slides oK. all simple ol'will

 

[BabaYaga]

Also maybe worth mentioning that on my boom, there's an internal car that the clew attaches to. Needs some replacement clips and maybe some new wheels. Two of the wheels feel right off due to a missing clip, but they are captive in the boom track.
View attachment 112577

Anyway, I'll be giving it a thorough clean, and replacing some very worn sheaves, and tapping some new threads on the gooseneck end.

When I put the ends back in, what should I use to stop corrosion between the ends and the aluminum boom, and on the bolts, and to ensure it all comes off easily next time i have to take it apart?

My boom has the same car, although no clips on the shafts. Difficult to see what purpose they serve, as you say, the wheels are captive once in the track. If I couldn't get hold of stainless clips, I doubt I would bother at all.

I believe the end castings are aluminium also, so I not sure anything is needed between them and the boom extrusion.

As mentioned, duralac is recommended between stainless or monel fasteners and aluminium. I chose to replace the monel rivets at the gooseneck, regarding the end casting stainless steel machine screws, my experience is that petroleum jelly also works fine provided that you take the screws out and renew every other year or so.