Hull damage from trailers

Boat trailers and trailering

Moderator: ttownshaw

gfar22
Posts: 2
Joined: Mon Oct 15, 2012 12:03 am

Hull damage from trailers

Postby gfar22 » Mon Oct 15, 2012 12:21 am

G'day , I'm Greg from Brisbane Australia.I built a Garvey 15' about 5 years ago and the boat works well [ except it tends to collect rainwater foreward].My problem is the rollers seem to delaminate the epoxy sheeting from the ply about halfway up the hull right at the midline angle.I've cut it out and repaired it once but now it's doing it again over a couple of feet length.

The trailer has only 3 rollers to support the hull in the front 12 foot and I assume the damage must be done as the boat goes in and out of the water.

Anyone seen this before?

grumpyoldman
Posts: 29
Joined: Mon Sep 03, 2012 9:54 pm
Location: Tampa, FL

Re: Hull damage from trailers

Postby grumpyoldman » Mon Oct 15, 2012 6:47 am

Rollers are not reccomended for wood hulls. Replace the rollers with bunks and I think the problem will be solved.

gfar22
Posts: 2
Joined: Mon Oct 15, 2012 12:03 am

Re: Hull damage from trailers

Postby gfar22 » Thu Oct 18, 2012 1:26 am

Thanks .Do you submerge the trailer and float the boat on?

User avatar
Roberta
Posts: 4433
Joined: Tue Jul 31, 2007 5:23 pm
Location: East Troy, Wisconsin

Re: Hull damage from trailers

Postby Roberta » Thu Oct 18, 2012 5:21 am

Yes, Submerging the trailer and floating on to or off of the trailer as much as practical is the best way to retrieve or launch a boat. Bunks are the best for cradling your wood boat. The bunks give you more square inchs of contact than rollers and reduces the pressure exerted on the hull per square inch. Wider bunks and more of them is best if you can accommodate them.

Roberta
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo underway.

greyrfox
Posts: 29
Joined: Wed Oct 03, 2012 9:37 am

Re: Hull damage from trailers

Postby greyrfox » Wed Nov 07, 2012 8:53 pm

grumpyoldman wrote:Rollers are not reccomended for wood hulls. Replace the rollers with bunks and I think the problem will be solved.


Will the bunks still work well for a larger boat like a 27' Coronado? I can see the spreading the weight issue but I was wondering about the friction factor due to size and higher total weight of the boat.

Rick

User avatar
raymacke
Posts: 640
Joined: Mon Apr 25, 2005 7:07 pm
Location: Marissa, IL
Contact:

Re: Hull damage from trailers

Postby raymacke » Fri Nov 09, 2012 11:15 pm

I haul my 27' True Grit on a bunked trailer with little problem loading or unloading. I would think with bunks you need to be in a little deeper in the water for both but it has not caused me any difficulty. Note - the True Grit has a semi-displacement hull and the aft hull is not flat so the bunks need to conform to the bottom. Here is a photo of my trailer -


Image

Because the Coronado is a planing hull I would think having a more conventional bunk setup would work well. Here is a photo of what is normally used for bunks when the hull bottom tends to be more flat in the aft sections of the hull.

Image
So Many Rivers,
So Little Time....

greyrfox
Posts: 29
Joined: Wed Oct 03, 2012 9:37 am

Re: Hull damage from trailers

Postby greyrfox » Sat Nov 24, 2012 7:32 pm

Raymacke thanks for the reply and the photos. Did you build that trailer yourself? Looked like aluminum I-beam is that what I see? Looks impressive. I seen where you also used a bunk for the keel support. I am thinking of using keel rollers mainly for initial contact of the bow as it it is being launched and retrieved so as to not cause damage until the boat settles onto the bunks. I can see rollers not being good to use in areas other than the keel but the full length structural member of the keel should not be a stress issue? I still have not purchased any books on trailer building so I am guessing that will be addressed. I loved the guide posts you used.

Rick

User avatar
Mr Hot Rod
Posts: 872
Joined: Thu Mar 03, 2005 2:40 pm
Location: Chelsea, Quebec, Canada
Contact:

Re: Hull damage from trailers

Postby Mr Hot Rod » Sun Nov 25, 2012 8:39 am

greyrfox wrote:I still have not purchased any books on trailer building so I am guessing that will be addressed.

I recommend Glen's book How to Build Boat Trailers. It covers all aspects of trailer construction and is written in easy-to-read non-technical language.


It's a real honour to have a photo of your custom boat trailer on one of Glen's books ! Ray Macke's Glen-L Series 1200/1800 trailer is featured in the upper right hand corner and our Series 2300/2800 trailer is in the top middle and lower right corner of the book cover.

____________________
Paul Kane
Kane Custom Boats Ltd.
Chelsea, Quebec

Building the Glen-L Hot Rod : http://www.kanecustomboats.com

Glen-L Boat Video Directory : http://www.kanecustomboats.com/pages/vi ... ctory.html

User avatar
raymacke
Posts: 640
Joined: Mon Apr 25, 2005 7:07 pm
Location: Marissa, IL
Contact:

Re: Hull damage from trailers

Postby raymacke » Sun Nov 25, 2012 11:50 pm

Grayfox,

Yes, the trailer is aluminum but I had it custom built for the True Grit by Boatwheels in Ohio. The bunk for the keel was suggested by the builder and was a good idea that hadn't occurred to me. It allows a good part of the weight to be carried at the strongest part of the hull. Sail boats often use a similar arrangement although their keels have a smaller contact area with the bunk.

I think a roller forward is a good idea. I have had a problem with excessive wear at the bottom of the forefoot. About a foot forward of of the end of the front end skeg it was constantly rubbing off the bottom paint and even worked on the epoxy and cloth a little. What happens when loading is the sunken trailer is setting at an angle and to forefoot contacts the carpet covered bunk. I usually wench the boat up the last foot or so and all the time the hull is dragging across the bunk. When I pull the boat out the aft end settles onto the rear section of the bunks and the forefoot is no longer touching the keel bunk but the damage is already been done. I solved the problem by adding a "Keel Guard" (see photo below). It protects the forefoot as it now contacts the bunk rather then the hull itself. Also I ran it up higher to protect the paint above the bow eye from wear caused by the bow roller. When winching on there is also a lot of pressure there and it was working on the hull paint. In the photo note the darker spot on the upper part of the guard - that's is from the "non-marking" roller. Paint is just not nearly as durable as gel coat.

With a shallow draft hull and lots of side area to catch the wind the tall rear guide post are a must for boats like the True Grit. When loading if there is a crosswind more than about 5 mph things can get real interesting. This is also the reason I usually can't just float it on the trailer as any wind will blow the bow to the side before I can get it secured. At that point none of the other bunks are catching anything and I must rely on planting the forefoot on the keel bunk solid enough to hold it. Also, there can be a tremendous amount of pressure on the rear guides. The rear of the trailer is sunk deep in the water and therefore the guides need to be very tall to reach. But when the side pressure pushes against the top of the guide post it creates a lot of leverage.

The original post were 1 1/4" aluminum tubes with a fairly heavy wall - severely bent them the first time out. I tried several times at re-bending and supporting them but no luck and I gave up. Made some new ones out of 1 1/2" heavy wall steel electrical conduit - bent them too! Re-worked them with additional reinforcement and they are now working fairly well. I have bent one since then under some rough conditions - 18 mph wind gusting to 25 at 90 degrees to the hull. Actually I managed to hit the trailer fairly well (got lucky) but just the pressure created while sitting there bent the guide post again.

The good thing is deep V boats like the Coronado have a lot less trouble with this. The V helps them to self-center much better and then tends to hold them in place. I had a 24' deep V Express Cruiser with no rear guide post and seldom had much problem getting it on and centered.

And yea Paul, having my Cabin Skiff trailer on the cover is a real Kick!
Attachments
Keelprot.jpg
So Many Rivers,
So Little Time....

User avatar
KX6D
Posts: 8
Joined: Thu Nov 01, 2012 11:46 am
Location: Whittier, CA
Contact:

Re: Hull damage from trailers

Postby KX6D » Tue Dec 25, 2012 12:34 pm

Mr Hot Rod wrote:
greyrfox wrote:I still have not purchased any books on trailer building so I am guessing that will be addressed.

I recommend Glen's book How to Build Boat Trailers. It covers all aspects of trailer construction and is written in easy-to-read non-technical language.

Image

I recently bought this book and I'm a little disappointed with it. If you would like to buy mine at a discounted price over a new one, plus shipping via USPS, I'd be happy to sell it to you.

I have a lot of experience with trailer building, although not much with BOAT trailer building. I was seeking one very specific piece of information on the angle of the cross frames for a V-bottom boat and this was not covered at all in the plans I purchased or the book. However, you might find it to be very educational! Let me know if you are interested.
Dino - KX6D

User avatar
raymacke
Posts: 640
Joined: Mon Apr 25, 2005 7:07 pm
Location: Marissa, IL
Contact:

Re: Hull damage from trailers

Postby raymacke » Tue Dec 25, 2012 10:11 pm

Perhaps those that have built a number of trailers may not find Glen-L’s book extremely helpful but on the other hand, I as a first time builder, found it very informative - even more so when used in conjunction with their trailer plans. It is designed to give the builder an overview of construction and some ideas for layout and accessories. Also, it is not just geared at Glen-L boats but to any boat whether homebuilt or factory.

If you are looking for specific measurements and angles I doubt they can be found in any book type publication. The problem is hull designs vary VERY widely. There are flat bottom boats to deep Vs to displacement hulls. Although the same basic frame can be used for many, the specifics will be quite different to accommodate a particular hull.

Sure, they could give dimensions that may allow highly adjustable bunks to fit a multiple hulls (that is what factory builders do). But is that what you really want? A trailer built like that is a compromise at best. If I am going to take the time to build my own trailer it is going to be custom built to fit my specific boat. This will result in a stronger but at the same time lighter trailer. It also allows you to design your trailer to carry the boat as low as safely possible making launching and retrieving easier.

The only way this can be done is to develop the measurements and angles directly from your hull. I did this when constructing the trailer (1700 series) for my Cabin Skiff. I made templates from scrap plywood at specific locations on the hull. I simply set them on the inverted hull and screwed the strips together to form the same angles as the hull. I then used the templates on the trailer frame to develop the angles.

Image

I had the trailer for my True Grit custom made by a company that builds boat trailers. For that the builder requested I provide the information so they could make the custom fit. Since the hull was already upright I had to get under the hull and take the needed measurements and angles and get that to them along with photos of the hull. I also need to do the calculations as to the center of gravity so the axles could be properly positioned. Although they do nothing but build boat trailers I had to give them my numbers.

I guess my point is that the book just can’t give specifics, as there are just too many variables. They could provide dozens of scenarios but odds are none would still work out as well as measurements and angles you develop yourself.
So Many Rivers,
So Little Time....

User avatar
KX6D
Posts: 8
Joined: Thu Nov 01, 2012 11:46 am
Location: Whittier, CA
Contact:

Re: Hull damage from trailers

Postby KX6D » Sat Jun 29, 2013 11:14 am

I'm sorry its taken me so long to get back to this thread. I also apologize for taking it slightly off topic.

raymacke, I appreciated your comments. You said... "Sure, they could give dimensions that may allow highly adjustable bunks to fit a multiple hulls (that is what factory builders do). But is that what you really want?" Actually, that was exactly what I was looking for! Was there an industry standard on say, three or four, angles used for production trailer manufacturing? I was hoping to find that in the book or the plans I bought. No such luck.

However, I agree with you about building it to match your boat! I originally came across Glen-L while searching for trailer plans I needed for a 1980 Beachcraft fiberglass boat I purchased. My original trailer has a flat 12" center section and I wanted to make it just a "V" to give me more ground clearance UNDER the frame.

So yes, the book has some fantastic material for the novice boat builder; it just didn't have the answer...which may not exists afterall...to my specific question.

Thank You for your excellent reply!
Dino - KX6D

Craig Aho
Posts: 291
Joined: Sat Jul 30, 2011 7:05 am
Location: Washington State

Re: Hull damage from trailers

Postby Craig Aho » Sat Oct 26, 2013 2:52 pm

If the book is still available I would be interested in your offer.

Craig Aho


Return to “Trailers and trailering”

Who is online

Users browsing this forum: No registered users and 1 guest