Starboard block for D S transducer and Cable Clam for cable

thataway · Posted: Fri Jan 06, 2012 10:11 pm Post subject:

Tom,
The problem is that very few things (including 5200) bond well to Starboard. So the answer is "no" --you can bolt the starboard to the aluminum, and seal with 5200--with the undercuts, but I would not relie on the 5200 along.

Ferrett 30, nice job!

Regards,

CaptainChris · Posted: Sat Jan 07, 2012 10:00 pm Post subject:

This will give you the technical data for 3M 5200 lap shear for reference. Adhereing polyethylene with anything is miserable and here is why the folks at Starboard™ do not recommend adhering "poly" with 5200, or anything else for that matter.
http://multimedia.3m.com/mws/mediawebserver?66666UuZjcFSLXTtlx&EO8TVEVuQEcuZgVs6EVs6E666666--
Safe boating...

thataway · Posted: Sun Jan 08, 2012 4:29 pm Post subject:

There are products which will allow bonding with Starboard and Starboard plus other materials. There are two products which can be used for adhering King Starboard--and similar Polyethylene and Polyproplene products:
3M Scotch-Weld DP8005 Acrylic Adhesive and Lord Corp #7540-AB. It is best to prep the starboard either by rough abrasion or flame treating the surface. The aluminum needs to be cleaned, and then an epoxy based primer to prevent further corosion. Search on either of these products will give what results have been obtained and the useage.

I prefer to use screws, plus a bonding agent. Some have reported very good bonds with the adhesive alone.

ferret30 · Posted: Sun Jan 08, 2012 4:38 pm Post subject:

Would these adhesives work for holding the starboard to gelcoat? If I have any problems with my setup I'd consider trying an adhesive only (no screws) approach to holding the block.

Tug · Posted: Wed Oct 03, 2012 9:04 am Post subject:

Looks like from the picture of the CableClam and with longer screws you could ...use the gasket to mark and drill your holes....place the gasket + top section of the CableClam on the outside of the transom .....and than place the bottom part of the CableClam on the inside of the transom.
Just may be a better method if i used the Cable Clam on my boats roof where it is only about 1/4 inches thick..but i do not know if this would work or is recommended.. Tug

Sunbeam · Posted: Tue Oct 09, 2012 12:59 pm Post subject:

thataway · Posted: Tue Oct 09, 2012 5:49 pm Post subject:

Tug,
I have used Cable Clams on the roof. Use shorter screws. Measure what you need.

Grazer · Posted: Thu Oct 25, 2012 12:24 pm Post subject:

Excellent topic, photographs and descriptions of project. I am in the process of doing my own starboard transducer mounting block. I have two pieces of 1/2 inch thick which I want to bond together for a 1 inch thick starboard. Bob, it looks like you bonded two pieces together. What did you use for adhesive? Did you undercut both sides? Does one have to reapply gelcoat to areas of the hull exterior not covered by a starboard replacement like this in order to maintain a water barrier?
Thanks,
Grazer

rogerbum · Posted: Thu Oct 25, 2012 1:57 pm Post subject:

thataway · Posted: Thu Oct 25, 2012 4:45 pm Post subject:

Agree with Roger, yes, I have used two pieces of 1/2" starboard. Just screwing thru them is adequate. The hole which the screw goes into has been potted with epoxy, thus no possible leakage into the hull. Undercut the layer of Starboard which is next to the hull, to get reasonable adhesion of the 5200 or similar adhesive/caulk.

Sunbeam · Posted: Fri Oct 26, 2012 1:08 am Post subject:

This may not apply, but just know that epoxy will deteriorate if exposed to UV (sunlight), so in that case you might want to gelcoat or paint over it (I realize you may not end up with any exposed to light in this case).