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I need some help in a few areas on my 28 bertram. Since they are seperate issues ill make different threads.

First off for some background. We have had this boat out of the water since we have owned it and i know thats been atleast 10 years. Plans got put off when i went off to school and got a job out of the area. Long story shorter the hull is very dry and hasnt been maintained. To make matters worse it was somewhat prepped for paint so that means no wax and exploring the bottom issues was underway.

Now today i go out at asses the situation and it doesnt look good at all. While i remembered there being spots that needed to be repaired now the bottom of the hull has cracks all in it. Some look more minor but others look really bad. So i have attached a couple pictures and need some help on what to do and if i can even save it.

Any tips working with the hull right side up are definatly welcome as flipping it isnt an option. Ive never glassed upside down before but from what i remember the key it to keep it light.

I bumped up the contrast on the pictures so the cracks could be seen better so they arent "quite" as bad as they look.

This is the bad one to where the gelcoat is falling off.


This one is what allot of the bottom of hull looks like. They dont seem to follow any real pattern or area.
:(

Not so bad.
Looks like just gelcoat stress cracks.
Not much of the gelcoat left to begin with. Sand it off (gelcoat) or have it sandblasted, or blated with other media. Clean w/ denatured alcohol, and apply a few coats of epoxy barrier, followed by your bottom paint.

This is the short answer, could be more to it.
Like rotten bulkheads and stringers which allow abnormal flexing of the hull...

Ditto - looks like gelcoat crazing from age and nothing structural. Sand it off, barrier coat, and go boating. Even tho its on a butt-ugly Hyena Boat, its still a Bertram.

UV

UV,
Its good to have you back around.

Just shot coffee thru my nose on your illustrious comments about the 28's looks.

You are back UV....giving the Hyena Boats hell. Have fun at the Point this weekend.

Garry

UV...

I have been looking forward to seeing you back here again! Maybe all those good vibes everyone here sent your way really did work. This place hasn't been the same with you away!

Actually I would be inclined to go a step further. Blast off what comes off (had mine soda blasted), then hand sanded the whole bottom with a RO sander. (I still think I have "random orbital elbow" from that adventure. ) I then filled and faired every poc mark and divet with epoxy and filler. I used west system with 410 filler. Work in small areas and mix small batches. Other guys might have differing opinions on what to use. Wet everything first with unfilled epoxy, then while still tackly apply epoxy with filler. Then resand everything smooth. Then apply your barrier. I used 4 coats of interpertect 2000, follow by 3 coats of bottom paint (1 marker and 2 topcoats.)

After 3 years I still get comments frm the guys thta haul me out that they can't beleive they are looking at a 36 year old bottom.

Got lots of pix if you want them. I can post some whan I finde them.

Thanks for the reassurance. Im glad it isnt as bad as i initally though. Thanks for the heads up on the process and products used. That will definatly be helpful. I wasnt sure on what blasting media would be the best to use so ill have to research the baking soda since i hadnt considered that. Have any of you rented a blaster and can comment on what size to ask for?

If you have pictures handy i wont turn them down but you dont have to go out of your way.

Thanks,

Major

Major, I used ground up corn to blast my hull, looked the same as yours, maybe a bit worse, I also have heard of walnut shells doing a fine job. I then filled and faired every inch of the hull with epoxy like Gif mentioned. Followed by West with barrier additive, rolled on six coats, then sanded the entire bottom again...Not for the faint of heart or weak shoulders..I would take advil befoe I started and go at it. BH

Now come the inevetable questions. It is possable to do some of the work on the trailer but at some point its going to have to come off. So short of having a motorized lift at the shop how do i get the boat off the trailer and on the a workable platform? It will have to be reuseable because i would have to be able to move the boat to fix the whole bottom.

This leads to yet another question. How do you properly block and support a 28 bertram hull? Right now the boat is pulled under a shelter with a concrete floor.

You can carefully use jackstands and hydraulic jacks on keel blocks to get it off of the trailer. Carefully being the operative word. Then lower it onto solid keel blocks. It will take a number of competent people working in concert to do it.