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For hydrofoiling I need a bit wider bar than the current Naish one I have. Otherwise is would be fine, but I would like it to be wider.

The options are either somehow lengthen the current bar at both ends (how?) or then make a new one by DIY. Any ideas or pointers how to do it, please?

Thanks!

prolly easiest to just buy a new one. I have an old liquid force 60cm for instance I could sell you for $10, bar only, if you are close enough that shipping isn't expensive. I think there are a lot of old bars out there that got parted up for the lines and parts. I also have a few other control bars laying around that are shorter.

Have a look here...
http://www.facebook.com/SKshapes
or http://www.skshapes.com

I am on the same boat. Not that I do not have a 60cm one

Would go with a carbon 22/20mm tube. Something like a Cloud bar. Simple, light efficient. Maybe an 20/18 tube as middle reinforcement or even for a full length.
Bar ends something soft. That's it.



PS, yep, that FB page is a carbon tube...What they do not reveal is probably a closed cell foam inside the bar. Otherwise they would need to seal it really well which I do not like coz of the hot air expanding inside...

Thx

Carbon rod was my thinking too, but how would one do the center hole? Obviously you need to somehow make the hole smooth so that it doesn't fray and cut the chickenloop line going through the hole, but what's the trick?

You could possibly cut your existing bar between the middle and end on either side and insert a tube to lengthen it?

typically you would want to machine the inner part of steel, basically a small cylinder of steel where the center of the cylinder is solid but the two ends of the small cylinder are hollow (to save weight) that you drill a hole through. You want the hole near the kite to be very large and the hole near the chicken loop to be smaller, machine it out so you don't get any edges and it is smooth all the way through. Then make a cut out in the two halves of the carbon fiber rod around the hole, glue it all together with some bar ends. That's a lot of work, and working steel is a bitch so I guess you can make that center portion out of aluminum that's not too hard to work but will not wear as well as steel. A lot of effort when you can just grab the part from a broken bar or find someone with a center from a broken bar for ask to buy it from them for $5. I take it you dead set on making the entire control bar yourself instead of buying a used one from someone.



you dont want to just drill a hole through your carbon fiber rod that won't wear well with the depower rope going through it.

It's also possible you could create an all carbon fiber middle piece, you know chop up a bunch of carbon fiber into filler, create a mold add the resin & epoxy to create the mushy stuff and pour the mix into the mold. That would make it all a lot lighter, but I like the characteristics of steel for that center piece, if I were building it from scratch. Steel isn't brittle like carbon fiber is so while I like carbon fiber for the bar part I don't like it for the center part that the depower rope goes through as much.

omg wrote:Carbon rod was my thinking too, but how would one do the center hole? Obviously you need to somehow make the hole smooth so that it doesn't fray and cut the chickenloop line going through the hole, but what's the trick?

The Smooth-On has a number of different PU's, different elongation strength, different shore, etc. What you need is a small quantity 320 PU, or almost any 3xx product depending on a pot life.

Than, you sort of isolate a middle part of a carbon tube and pour the PU in to get a 'plug' inside. This would be so strong that there is no need for any metal. Look at the FB page, there is no metal anywhere The trick is to have a carbon tube intact to profit by it's strength.

Next step, drill the hole. I drill carbon with a wood drilling bit. Slow speed, very sharp bit (all dull now .

The total cost for a tube + plus PU is like $10 or less. There is no way you'll wear a PU in 1-2 seasons with Dyneema rope. My Zian bar has a clear plastic middle part, if the production bar has it, you'll be ok as well. Look closely how simple this FB bar is, perfect for HF (I do not like the line 'leaders' tho, not on this angle. Bad design me thinks).

D.

PS
edt, it's not a 'big/small' hole. It is the 'optimal' size for the rope. As said, you do not have a benefit of carbon tube if cut in half. It would be a cosmetic addition, that. If you cut it, one must 'beef' up the ends with ie a UNI tow carbon, coz biax is not great.

Just built some from a $25 carbon MTB handlebar (9 deg bend). You can attach a low-friction ring using some carbon roving in the middle, and the steering lines using a prusik friction knot near the ends, about 6 wraps. With corks on the end this bar will float, and you can adjust the effective line width by sliding the prusik knots on the bar. I added a slightly thicker stopper ring on the end as well, but since the prusiks aren't moving at all I now think that this is pretty much optional. A slightly wider cork is really good enough.

Gwicke, I would like to see the bar you made. Do you have any pics you could post?