Matt and Wannabe,
The slick bunks will help.
There are inherent problems to building a trailer for any catamaran. Basically, the sponsons sit on top of the bunks, which causes the catamaran to sit higher on a trailer. All v-hull boats are able to nestle lower onto a trailer because the bunks are positioned on each side of the centerline of the boat, so the keel can sit much lower than the bunks on the trailer and easier to launch and retrieve.
For catamaran trailers, you must back deep into the water to retrieve your boat. Next time note the antgle of your trailer at the ramp in relation to the Tomcat (which sits level with the water). It should be obvious that as the catamaran approaches your front bunks, it must ride up the bunks to meet with your bow stop. There is so much pressure on the front of the sponsons that it can't help but wear the gelcoat off. The carpeting is very abrasive for something to slide across.
The thought of having to re-gelcoat my sponsons because of this inherent problem does not seem right. So, I apologize for repeating myself to those following this thread, but this is what I have done to "solve" my problem:
1. Re-design the front bunks to a v-hull design for each sponson. This allows me to guide and hold the front of the boat in place for a perfect retrievel every time.
2. The v-bunks provides more surface area to spread the load of the front sponsons instead of concentrating the load on the knife edge of the sponsons.
3. Install the slick bunks instead of carpet on these v-bunks to help reduce wear abrasion as the catamran rides up to the bow stop.
4. Installed side guides on aft end of trailer to hold back of boat in centerline of trailer for quick retrievel.
5. Increased the length of my trailer tongue by 2-feet so that I could get my trailer further back into the water to help the boat reach the bow stop with the least amount of friction as possible.
6. I also changed the front bow stop design to provide a more positive for me to know when the boat was in the proper forward position.
7. Finally, my final modification will be to replace leaf-spring axles to torsion axles, which will lower my boat to the waterline about 5-inches.
I have seen a trailer design where the bunks rest under the floor of the boat, between the sponsons, where the sponsons are dangling freely. That would certainly make launch and retrievel easy but I was apprehensive about whether the Tomcat's underside could take the weight. The hassles of finding the answers were too exhaustive to think about.
Some of you may ask why don't all trailer manufacturers implement this design if it is so good and all I can tell you is it is a matter of costs and not enough demand for catamaran-designed trailers. While the end user would pay an additonal $300-500 for a trouble-free trailer, most of the manufacturers have experienced that the boat purchaser doesn't want to pay anymore than they have to for a trailer. Most boat owners just trust they are getting the right trailer for the job.
I would guess that the wear on the bottom of the sponsons is on every trailered catamaran but most people don't bother to look and let their dealers know of the problem.
When I vented my frustrations to my trailer manufacturer (a big West Coast manufacturer), it fell on deaf ears and they did not want to listen to some boat owner. They did offer to provide any parts I needed but that was of little matter to me if they weren't going to redesign the bow stop and front bunks. So, I took matters in my own hands and, at my own expense, made the changes.
I found a local trailer manufacturer, who made me sign a liability waiver, who would build the v-bunk section for the front because they had the ability to lift the front of the Tomcat in place to take the proper measurements for the angle needed for the v-bunks. Being paid time and material, he listened patiently and did as I asked, even making some refinements that I liked. It took a couple of modifications before I was satisfied, then I took the parts I built with his to a galvanizing company. His charge to me was $750.
Lucky for me the boating community is in a down economy because he told me he would not had the time or willingess to modify another manufacturer's trailer before the downturn. But they were short of work so he was willing to work with me. Because it was not his trailer I was criticizing, he was not defensive and said all the changes I made were the right ones. Therefore, I am confident of sounding off my opinion in this forum.
George
