I am repairing a carbon batten, I have done this a few times now.
This time around the carbon I have is a little thicker, any tips on how to keep the carbon attached to the batten while I wrap the carbon around it. I use heat shrink tape to compress the laminate after I got the resin and fibre down.
I though of just putting a little resin on just the edge of the circumference of the tube... 
with the carbon and then let that cure and then wind the carbon around, better ideas?
I would imagine you would use a single roving and use what ever you have e.g. masking tape insulation tape , then wet the roving out ?
12mm batten
If you are repairing 12mm battens you use about 100mm of 10mm batten up the inside, file a chamfer on each end of the 10mm so that the glue will not be pushed up in inside the tube, mark the mid point on the 10mm, use araldite to glue together.
10mm batten
If you need to joint 10mm tube, get yourself a piece of 12mm tube about 150mm long, length ways ile the tube so there is a "C" section left just over 1/2 the cross section, on the inside of the tube where yoou have just removed the material file a chamfer on both the inside edges. This is now your tube aligning jig.
To join the 10mm tube you will need some standard solid round batten about 80mm and again chanfer ends and marks middle
Finishing
Get some fishing rod thread put the batten in your drill, support the other end and apply thread.
Varnish the tread afterwards and then apply some heat shrink
superglue, sticky tape, friend's finger, peg, mouth, vice grips, rubber band, brick, car tire, hydraulic press, band aid, angry hercules beetle: all together works best.
Thanks for the all responses,
probably didn't explain the question well enough, when I have done this before, I found that when i wet the fibre out, it still does not naturally follow the tight radius of a batten. Pulling it tight just unrolls the carbon, the shrink wrap fixes most of the problem though.
Just thought I would try and just glue the edge first then I can pull the carbon firmer, could I use a superglue or something else, that wont weaken the resin?
Or is there another trick?
as powersloshin said you need to glue the dry fiber to the dry batten , then wet the fiber out , if you have a single strand you can put on heaps of tension
Have never used carbon or glass, tried once the pain in the freckle factor was way to much.
Done heaps of battens the other way and never an issue, repair takes about an hour to complete
Given the batten is unidirectional(?) why go around with the carbon?
Use unidirectional along the axis, wet with minimal resin (ie looks like not enough) then wrap tight with electrical tape. The recoil effect of stretching electrical tape will be plenty tight. Or yeah heatshrink but that can be a bugger to get over something that wants to fall off...
Select to expand quoteMark _australia said..
Given the batten is unidirectional(?)
It's pultruded carbon,
Just trying to improve my layup skills, I thought tape would create a void as I roll the carbon over more than one layer. Will give superglue a go but I thought that also would create a weak spot.
I've never fixed a batten but I've done a few booms. I use masking tape to fix the beginning of the rovings in front of where I want them to be, the tension can be applied to get them tight. I wet out the boom area with a small brush, wind the strand over that, then brush again. Of course with a curved boom section, I'm winding in opposite directions with alternate strands at long angle along the boom. It's almost impossible to keep any tension going along the curved boom. After resin is set I just remove the taped down section,
bead of superglue did the trick.