Mainsheet track on carbon

[Variant 2]

I am considering using a carbon aft beam for my cat project. What is the best way to fasten an aluminium mainsheet track to a round carbon section?

[Variant 2]

Thanks for the info

I hadn't actually thought of through bolting. I could probably then use the same bolts for net attach points under the tube

[TimB 7]

Bolting right through a round tube sounds a bizarre idea to me. It would need stopper tubes to avoid compressing the tube. Normally you would only bolt through the top side with various tricky methods of fitting and holding nuts. Of course we don't know how big the project is. Are we talking about big or small cat here? What size is the carbon tube?

tb

[wheels 543]

Also, treat carbon as a "Hostile" element just as you would with Ally against SST. Except in this case, SST against carbon will also suffer from corrosion if the right situation occurs. Carbon is conductive, so in the right situation, it will cause galvanic corrosion. Isolate dissimilar materials with either plastic washers/sheet or urathane bedding compounds. When ever I want some plastic to isolate something with, I simply cut up icecream containers/lids. It is a great thickness and cheap. Make sure all bolts are coated with tefgel or lanocote and washers need a plastic spacer if they are pulled up against the carbon.

If you form a hollow in the track as MB suggested, make sure you bed the track down with a sealant. The anodizing will have been removed and subject the Ally to greater corrosion risk.

I kinda think using a really good Bedding compound like the Sika 5900, between the track and the tube would be the best bet. It wouldn't think it to be too heavy.

[Battleship 100]

Have you considered a bridle system?

Would save a lot of issues and very light.

[Variant 2]

Thanks Willow. Maybe I will now I'm finding out how complicated it all is lol

The tracks and cars aren't cheap either.

 

TimB. It is a little big cat. 6.5 metres long. Tube is around 130mm

[Clipper 344]

I bolted the aluminium track on my cat (GBE) to the aluminium rear beam. 30 1/4" SS bolts, and and I wanted to isolate those from the ali. So I used a nylon washer, then a stainless washer than a nyloc nut. Superglued all those 3 together, and then used a socket on a fibreglass batten to get to the middle of the beam. first one took a while to sort out, but then samin and I did the other 29 in about 90 mins I reckon. Used lots duralac in there too.

[Variant 2]

Thanks Clipper. That sounds like a good method also. Definitely not a job that could be done alone.

[Bad Kitty 252]

Or you could look at glueing/taping a glass tapping block on the top of the beam & drill & tap into that. The added bonus is you won't reduce te strength of the back beam by a huge amount by drilling a shed load of holes thru it.

[Variant 2]

Thanks Bad Kitty. I now have more options than I can shake a stick at. I'll ponder these. In the mean time I've added a few new pics to the thread on the boat so you can all see what this is for.

 

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