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‘89 HST rebuild ( Blown out bottom)

Posted: Nov 26, 2022 11:17 pm
by alaskastreamin
I picked up this 6/89 HST this summer for the value of the trailer. It was 3-1/2 hrs away so we ran over and picked it up.

It had hit a wake boat wake and the bottom blew out leaving a massive hole.
The owner was able to get to the beach before it sank.

The hull flexed hard enough to pop the plywood floor loose from the top of the tunnels.

Here’s some pictures to get you all up to speed.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Nov 26, 2022 11:27 pm
by alaskastreamin
Today I got her inside , off the trailer and up on its side.

Looking thru the hole I could see what happened.
The center stringer was never attached to the forward bulkhead. It ended about 18” away…..That’s where the hull collapsed and imploded.

The floor is separated from the tunnel top and there’s a 2-1/2” gap at the toe board bulkhead.
The bulkhead at the rear of the floor is tore loose as well. It appears the “mid” 89 models got a better layup was just after this 6/89 one.

So far the balsa that is visible is golden. Even at the edge of the hole it’s golden.

Tomorrow I’ll pull the deck and make a jig to set the hull on for the repairs.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Nov 27, 2022 9:36 pm
by alaskastreamin
Day 2

Sawzall the opening until I get to non-fractured fiberglass. Start cutting out the form boards .
I assumed the side walls from the tunnels were 90*. Wrong-O!! Outer sponson wall is 93* and the center sponsen is 97* .

All the panels need to fit snug to get a nice tight repair.

I had to router a 1/2” radius on the sides so they would fit properly.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Nov 28, 2022 10:29 pm
by alaskastreamin
Day 3

Today I attached the side rails to the tunnel form and another strip outbound of those. That’s as far as I can go with the forms until I remove the bulkheads and floor .

The transom and knee braces were removed and the deck popped right off.

Once the side rails were removed along the sides of the floor, the floor plywood lifted right out. It had totally popped loose from the tunnel tops.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Nov 30, 2022 9:55 pm
by tnelson77
Hats off to ya, Ron! Thats quite the project.

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Nov 30, 2022 10:39 pm
by alaskastreamin
Day 4

Technically it’s day 5 but I took yesterday off to run errands, order the fiberglass stuff ($500) and 6 colors of gelcoat (another $500).

So day 4 working on it.

Got 10” snow last night so not a huge production day.

Scraped off the last couple layers of the floor plywood from the tunnel tops. You can see the areas the floor was actually attached. Where it wasn’t, there’s super dry chopper gun fibers. They don’t even look like they were compressed. Probably an in-experienced operator not laying it down even.

Removed most of the foam that was poured at the joint. Checked the sponsons foam and all dry.

The upper deck had a couple fractures so I flipped the deck and sawed thru the tears to get everything to lay flat again.

It looks like the hull and deck were built with 2 layers 1-1/2 oz. chop mat and a 1708 stitch mat . That’s what I ordered to make the repairs.

Most of the deck is covered with stress cracks. The gelcoat will be removed and I’ll look closely for fractures in the chop mat. On the underside, the 1708 has no fracturing so that’s a good thing.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Dec 05, 2022 5:23 pm
by Hippie459MN
WOW! That had be one heck of a hit! Glad they got back ok.

Can't wait to see this come along. As with everything you do, this should come out amazing!

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Dec 05, 2022 10:46 pm
by alaskastreamin
Thanks guys!!
This one is really messed up. I’ll get it though.

Got all the grinding done, floor, bulkheads, knee braces cut and fit. Got the tunnel forms set on the jig platform, plumb, square and level.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Dec 06, 2022 5:20 pm
by alaskastreamin
Today I ran some string lines to make sure everything is true. I added an extra brace for the front end of the jig to get rid of some minor flexing in the aluminum stiffeners.

Got the rest of the mold put in place and made some radiuses with Sheetrock hot mud.
Two coats of Johnson paste floor wax was applied to the mold finished off my day.

The fiberglass materials won’t be here for a few days so I’m on hold for now.

[ Post made via iPhone ] Image

Re: ‘89 HST rebuild ( Blown out bottom)

Posted: Dec 06, 2022 5:22 pm
by alaskastreamin
Forgot to add the string lines.

[ Post made via iPhone ] Image