diameter of bolt rope in trampoline for C rail

[Don Wylie]

Does anyone know of the optimum rope diameter for the tramp to insert into the c rail. I used 5 mm but that is too small and pulled out. I am assuming 6 mm with the thought that 7 mm is too much. Unfortunately my boat is not here to test diameters. 

thanks

Don

[Don]

Hi Don,

I have used 8mm shock cord that works.  If you have 7mm cord or line that should work.  Always sew the corners with waxed thread as this is where the tramp will pull out of the aluminum extrusion.   You probably will have to drill a small hole through the aluminum extrusion and hull deck joint or if there is a rivet at the end, whats left of the mandrel can be punched out with a nail and use this to sew through and also through the tramp.  I do not have any problems with the tramp pulling out of the sides.  You should also consider making your tramp a two piece if you haven't already done so.  One thing I have found in fixing some older tramps is whoever made the tramp used wooden doweling for the first 3 or 4 inches where bolt rope should be.  This of course rots and the corners pull out.  You may have to spread the extrusion slightly to help when putting the tramp in.  I also found Sailkote (dry lubricant) helps a lot when loading a new or fixed tramp in the extrusions.

Don

[Don Wylie]

Thanks Don. I will try the 7 mm rope. I used the technique of sewing the corners but the fabric used there tore so will have the seamstress toughen up that fabric.

Don