C-17 Stitching

[rezab]

Hi everyone, I've just started to stitch together the bottom panels for the c17 and wanted to check about a few things. Overall, I think it looks ok, with a pretty uniform gap between the two panels down the length of the boat.

That being said, there are a few things I'm unsure about. First, when the panels are on and stitched parallel down the center of the boat, the back end of the panels does not sit parallel to the transom. Is this ok?

Second, is it ok for there to be a gap between the panels and the molds. At station C, there is about half an inch gap at the most, and about 1/2 to 3/4 inch between the panels and the mold at station A/ bow mold.

p.s. sorry for the sideways pictures.

[narfi]

Hi everyone, I've just started to stitch together the bottom panels for the c17 and wanted to check about a few things. Overall, I think it looks ok, with a pretty uniform gap between the two panels down the length of the boat.

It looks great!

That being said, there are a few things I'm unsure about. First, when the panels are on and stitched parallel down the center of the boat, the back end of the panels does not sit parallel to the transom. Is this ok?

I think this is fairly normal, I think I had that a little on my FS17, perhaps because the panels are going around a compound curve forward it pulls a bit so that the panel which 'square' when flat is pulled forward a bit when bent into shape?
It is easy to fill the gaps with epoxy/wood flour mix and sand down to a good radius before glassing.

Second, is it ok for there to be a gap between the panels and the molds. At station C, there is about half an inch gap at the most, and about 1/2 to 3/4 inch between the panels and the mold at station A/ bow mold.

A little gap is ok, but for larger ones I used a screw loosely holding it to about a 1/8" gap while doing the initial taping and then removed the screw once it was held into shape. You do NOT want to screw it down hard because you want it to take its natural shape along the whole length so there doesnt appear kinks in the panel.

p.s. sorry for the sideways pictures.

I have found that for pictures I take with my phone (only camera I own), I can open them and 'edit' them by cropping slightly, this serves 2 purposes, 1. it reduces the file size for uploading, and 2. it embeds more information than the original picture had for some reason and will now appear right side up. (you will find a few jokes here about people building their boats hanging from the ceiling in their garages )

[TomTom]

The most important thing is that the panels are fair and even and symmetrical. What you don’t want to do is push panels out of shape to get them to fit a mold and the get waves or deformations.

Remember it’s almost impossible to predict how every single type of plywood will bend - so it’s only natural that they won’t fit perfectly to the molds. Until you glue them in and they become part of the boat the frames, they are there to mostly there to help support the panels - give you some guidance and make life easier. The panels stitched together Is what defines the shape of the boat ...

From what I can see it looks pretty good!

[TomW1]

It looks real good in the top two pics. Let it set a day to settle into its natural form. Do not worry about the inside frames at this time. You want a smooth and faired hull on the outer hull at this time. The inner frames can be adjusted down the road, once you flip the boat. Keep the pictures coming.

Tom

[OneWayTraffic]

My C17 was sitting a lot more above frame C than that, but was closer to Frame A. It didn't worry me much; I'll just have a little less curve there.

Check there's no hook or rocker, wait a day or two then start gluing.

[Dan_Smullen]

It will show up later, when you're setting stringers and frames. Whether or not this is detrimental or not is another question.

Hull panels on my C19 pulled away like this at the bow. As the stringers were set inside, parallel to the flat aft section of the hull, they ran straight, and the hull pulled away from them. Does that make sense?

Gaps between the inside of the hull panel and frames B and C were filled with thickened epoxy, and I do have a slight, but noticeable bulge at the bottom of my boat were the keel turns up to the stem.

I think it's just aesthetic, and maybe even having a bit of a bulge in the front of the boat will have a positive effect on performance. Who knows...

At the end of the day, I'm a little OCD, and would have preferred to have spent a little more time trying to get them to lay flatter during stitching, but with this craft, somethings just need to be "fine".

[rezab]

Hi everyone, I've stitched the side panels on, and am getting ready to glue the panels together.

Everything looks good for me, except for around station 3 where there is about 1/8 inch hook.

Is this something that I should be worried about now, or is this an issue for when I am fairing?

[Fuzz]

I would deal with it now rather than later. Screw a straight 2x to the hull until you get the hull taped together.

[OneWayTraffic]

By Station 3 do you mean Frame C? Hook there won't affect performance at all. I'd see if you have anything pushing against the panels first.

I had some rocker in the back half of my hull. Ended up fairing it out. It was a bit more than 1/8". Get rid of it now if you can, but even 1/4" isn't going to ruin the boat. I ended up gluing the panels to my stringers to get them straight and I still had issues. May have been related to building outside

[rezab]

By Station 3 do you mean Frame C? Hook there won't affect performance at all. I'd see if you have anything pushing against the panels first.

I do mean Frame C (such is the problem when posting past midnight). Does the hook around Frame C not affect performance because it's not part of the planing surface?