Atkin - IKE build

[keen2build]

Hi there all,
Just looking for a bit of advice on the forward sheeting of my build. I have mocked up the pieces of ply into "strips" for want of a better word and was wondering if I am on the right track with this? The hull was supposed to be done in 3/4 x 5" timber, but that wasn't an option for me.
Any ideas or suggestions would be greatly appreciated.
Keen

[J.Madison]

Re: Atkin - IKE build

If you get some half-thickness ply and do it in two layers with the joints staggered that could work well. Epoxy the layers together of course. With just one layer you could do scarf joints but that is pretty complex. Another option would be to glue in the full-thickness planking and then hog out a few inches each side from each joint and fill it with roving before the final glass layer.

Maybe too late, but the bottom could be glued lapstrake. That will take a complex shape well.

[keen2build]

Re: Atkin - IKE build

Thanks for that, yes the thought of doing the bottom in lapstrake had occured to me, but as you say....too late.
I will battle on with how I am doing it, with enough epoxy, glass and fairing compound it should work?
Keen

[keen2build]

Re: Atkin - IKE build

Does anyone have any info on how to determine the transition point on the chine between the hull and side? My plans don't give me any of this information, so I have taken a guess as shown in the previous photo.

[TerryLL]

Re: Atkin - IKE build

This is the type of problem people get into when they try to plank a carvel design with plywood. There are so many exceptional plywood designs out there that it boggles the mind why anyone would dredge up an old carvel hull and try to do it in plywood.

Peel off that plywood and plank it as designed, or start over with an appropriate plywood design.

Sorry to be so harsh, but really, do a bit of research before you start a project like this.

[Small boats rock]

Re: Atkin - IKE build

You mention 'timber' was not an option. Can you comment further? Is that a budget consideration, or something to do with tools, or skills, or...?

[keen2build]

Re: Atkin - IKE build

I probably should have explained this point better. Most of plywood is leftovers from previous projects a long time ago, so i thought to put them to better use rather than see them "rot" away. The plans (very sketchy) were given to me by an old friend, who has since passed away. I have built other boats in the past, these have been hard chine and glued lapstrake sides, so this is probably the main reason for my thinking that ply could be used for this build. apparently I was wrong (see TerryLL comment above)

[Small boats rock]

Re: Atkin - IKE build

Given that you set out to create a boat from unlikely 'leftovers' it appears you're doing ok. Strengthen those joints with enough glass and you'll end up with something at least functional and no doubt fun when you're on the water.

[jpatrick]

Re: Atkin - IKE build

I looked at the Atkin website and see that Ike is a hard chine boat. It appears to have a much less complicated fore section than the Ninigret that I'm currently building. Atkin specs Ninigret to be planked in 3/8" ply and although the bow is difficult to do, it is not impossible. The 3/8" takes the form beautifully. So I see no reason whatsoever that Ike cannot be built in the same manner. Like J.Madison says, use two layers of 3/8 in order to get your 3/4. You will achieve a truer form with less fairing.

Jeff

[keen2build]

Re: Atkin - IKE build

Thanks men, all points taken and I thank you for your input. BTW, I am sheeting the boat in 12mm ply so 2 x layers of 6mm will be easier than jpatricks' Ninigret with a single 10mm sheet up the front.
Back to my question, "how to determine the transition point on the chine between the hull and side?

[slacktidemike]

Re: Atkin - IKE build

I assume by "hull" you mean the bottom sheathing. I don't know of any firm rule regarding where to make the transition joint. It's hard to tell from your picture, but it looks to me like it ought to be at the third frame.

[jpatrick]

Re: Atkin - IKE build

Thanks men, all points taken and I thank you for your input. BTW, I am sheeting the boat in 12mm ply so 2 x layers of 6mm will be easier than jpatricks' Ninigret with a single 10mm sheet up the front.
Back to my question, "how to determine the transition point on the chine between the hull and side?

I also struggled with this on my Ninigret. Then it occurred to me that I didn't actually have to have a transition at all. The bottom ply can be beveled more and more so that it will plane out with the topsides. Of course that's ridiculous because the bevel becomes so acute that the entire surface is planed away. So you just have to make a decision, based on what is happening on your boat, when to stop. That is the transition point. It's a value judgement that only you can make.

Jeff

[keen2build]

Re: Atkin - IKE build

Gentlemen,
Once again, I thank you for your valued advice and opinions on this. I think with a few beers and a little quiet time, I will decide the workable location of the change.
This s ite has been a wonderful source of info for any bumbling newby like myself.
If not for entertainment only and if I think it is worth a photo or two during the build, I will forward them on.
Trev

[Bill Perkins]

Re: Atkin - IKE build

The transition point is relevent to boats with caulked seams .If the bevel of the plank becomes too acute it will not be strong or stable enough to hold caulking at the chine . In glued up ply contruction this is not an issue .On my own glued up boat I made the transition when the bevel reached 45 degrees -just because that was where the bevel of my power tools maxed out .

[keen2build]

Re: Atkin - IKE build

Just a couple of pics showing the progress on the boat. The forward section shows the first layer of 6mm and seems to be going ok. I am wanting to glass the bottom and first strake mainly for beaching (but not at ramming speed) reasons, can anyone advise, what weight of cloth would be suitable for this?
TrevResized_20230610_121151_1636.jpgResized_20230610_120506_3097.jpgResized_20230610_120607_2309.jpg