Thread: Skicraft ski boat

G'day Mark,

If it was me I'd be getting rid of all the paint, it's not just getting a good bond onto/into the wood but it's also the bonding between the paint and the new epoxy - which I'd reckon would be really doubtful. All the best.

Rod

If you're going to sheath the boat, then you'll want as much of the paint off as practical, though some very small flecks can remain. The paint will accept the epoxy bond, it's just that the epoxy will be relying on the paint's adhesion to hold it in place at these locations, which is why you need to remove darn near all of it. As a bare minimum, shoot for at least 90% removal, with a higher percentage being better.

Thanks guys. I guess I was being a bit lazy. I have actually removed a lot more paint anyway as can be seen in the photos, but I guess I'll get into it again.
When glassing, I would obviously like to have a continuous cover across the hull. The photos show a 6mm ply strip running down the centre of the hull. I am unsure whether to:
1. fillet the edges of this strip and then lay the glass straight over it
2. Glass up to the strip, glass on top of the strip separately and then maybe add (or not) a fillet each side.

I wonder whether the strip has a keel effect at all in helping to maintain direction. If so option 1 would lose this.

Any thoughts?

Cheers, Mark
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This is a pretty wide and shallow strip, so not a lot of directional stability will be offered from it. I'd just epoxy it down and fillet the edges, after rounding them over pretty good. Once this is done, you can 'glass over the whole bottom, strip and all, without worry. After you've 'glassed and painted, you can install a sacrificial rub strip, which is usually just a 1x2 (20x40 mm) strip, down the centerline. This will offer some straight line tracking improvements. It's considered sacrificial, because it'll get beat up on the trailer and being dragged over rocks and stuff, so bed it in polyurethane or polysulfide. Use screws just long enough to hold it on, say short #6's, so if you bash into something good, the screws will pull out and not take half the bottom with them. It's cheaper to replace the rub strip and it's dainty fasteners, then a hefty one that's torn big holes in the boat's bottom.

Thanks PAR.
That was my preferred option, so good to have some confirmation. I hadn't considered adding a keel strip after painting but that makes good sense. And it shouldn't be too hard to find an appropriate off cut lying around

Bottom has been glassed and painting commenced.

I have been thinking about the prop position. As shown in the photos, the prop sits about 60mm past the transom. I wonder if this is correct?

A bit of history may be in order.
The prop, shaft and skeg were changed when the V8 was installed. While the new skeg was mounted in the same position as the old one, the shape may be very different resulting in the prop being further back.
When the boat was running, albeit very briefly, it used to create quite a rooster tail. The cav plate was increased in size (depth only I think, not width) but no-one remembers if this fixed the problem.
I figure that if the prop needs to move forward, now is the time to make the necessary changes. The skeg actually sits on a built up block, so to move it forward and closer to the hull will be simple.
So is there a norm in regards to prop position in relation to the transom?

Mark

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Hi Kingfisher
I have to stretch back 30 years to my days in the Victorian Speedboat Club at Albert Park Lake and Eppalock but to my mind I never saw a propellor that far back.
I did a few searches on Google and found Webletter12 on the Glen L marine inboard installation guide that contains detailed diagrams and a lot of text on propellers and shaft angles etc.
Google - Glen L marine inboard installation.
Other Seacraft owners might also have some input.
Cheers
Bagman

Hi Bagman,
I had seen a reference somewhere else to the Glen L article but couldn't find it. So thanks for the details. It makes a good read on some points but doesn't quite get around to my situation - but it gets close. The figures they mention for clearance to rudder and hull may suggest I can go forward with the prop - I'll have to get the steel rule out.
As all their designs show the rudder under the hull, the prop is naturally under the hull as well.
I'm starting to think there may be nothing to lose by moving it forward a bit - maybe 50mm. I'll have another look on the weekend.

It would certainly be good to hear from owners of similar boats!!
Cheers,
Mark

Hi Kingfisher
I'm glad there was at least something in that website for you to consider.
After my post I realised it was more like 43 years ago that I was a callow youth doing fast laps with my Dad in an old timber ski boat in an all too shallow Albert Park Lake. Thanks for rekindling the memory.
Cheers
Bagman

I had a good chat to Steve Moritz about it all. He still plays around with fast boats along with paddlesteamers, trains and running for council.
He suggested that it's not necessarily bad and can show pictures of boats with the whole prop behind the transom.
However he figured that there was nothing to lose in bringing it forward and that the handling would possibly improve at speed.

So that's what I've done. I brought it forward one hole - about 65mm.

Coincidentally (or not?) this now has the skeg sitting on the 'keel' rather than on a built up base, the prop just forward of the transom, 1" behind the skeg and 1" from the hull. All as Steve suggested a social boat would normally be set up.
So maybe it was meant to be? All will be revealed in a few weeks.

Mark