Eureka Canoe - Page 7

bitingmidge · #91 31st Jan 2006, 09:12 PM

Quote:

Originally Posted by deepdug

The more this thread continues the more comments I think of about my trials during construction. In the end I know that it cannot be too difficult or I could not have done it in the time with the facilities at my disposal.

Doug,

That's a bit of my fault I think... I've succeeded in taking a perfectly simple boat which can be built by anyone in a few weekends with almost no tools, and turning it into an intellectual exercise... or more correctly an exercise in procrastination!

If you go back to the first page, you'll see that the prototype panels me took err....7 or 8 years, and I must say I remain eternally grateful to Michael for being on a sort of sabbatical for the whole of that time, and not once asking me what became of them!

You'll also see that I was optimistically expecting to have the thing finished by Christmas ... .... ...

2004! :eek: :eek: :eek:

I'm really pleased that you are here to provide a balance!

Cheers,

P

bitingmidge · #92 31st Jan 2006, 11:38 PM

Quote:

Originally Posted by Boatmik

Thanks for the additional feedback on the decks. What thickness ply did you use? This is one of the areas that Doug mentioned was less than fun.

Doug has shown that it's entirely possible, if a little challenging!

I just happened to have half a sheet of 6mm gaboon left over from building Gruff (well it's only been ten years!) so the decks and seats were 6mm five- ply.

Even with one ply sanded off, it's still very stiff. I've been cogitating over Doug's pics for a bit this evening, and the 4mm ply would have been perfect, but.....

I'm thinking of building a form, routing the guts out of the underside of the ply, sticking it in a bendy form, then epoxying one side. I know... I know....but it should make fitting the already cambered deck a doddle, and it means I can put off the glassing for another week!

Cheers,

P

Daddles · #93 1st Feb 2006, 09:15 AM

Hey Peter, how'd you go with that jig to route the middle ply out of all the plywood? How much weight did you say you were going to save? Oops, you asked me not to mention this to Mik. Sorry

I

Richard

Boatmik · #94 1st Feb 2006, 08:31 PM

Quote:

Originally Posted by Daddles

Hey Peter, how'd you go with that jig to route the middle ply out of all the plywood? How much weight did you say you were going to save? Oops, you asked me not to mention this to Mik. Sorry

I

Richard

I've got my beady eyes on both of you.

MIK

bitingmidge · #95 1st Feb 2006, 09:15 PM

Quote:

Originally Posted by deepdug

One of my thoughts was to cut the spreader at the centre and try to push the sides out and then glue a piece into the middle maybe of contrasting wood to try to make it look as if I meant it.

Doug,

I reckon by the time you do that, and scarf a bit in to splice it back together, you could have cut the other one out.

On thinking about it a bit, you could end up with a nasty "S" shape in the top panel of the hull, because it will want to rotate as you push it out, if you don't let it (by keeping the spreader in place)...something won't work (or you could end up with an inverted V shaped spreader!

cheers,

P

bitingmidge · #96 1st Feb 2006, 11:11 PM

Enough of the nonsense! Here's some progress at last..

Pic 1) Free of clamps and that temporary gunwhale for the first time! The inwhale and centre spreader are now glued in place, so the shell is now a stable (and very light) form.

I have got a few "woofs" in the bottom as a result of the light ply used, so will look into it when the boat is turned over, and decide if I'm going to paint or varnish then.

Pic 2) Inwhale detail. It looks a mess now, but this is the one job that belt sanders are good at; cleaning up four different grain directions, edge grain ply and epoxy dags. Watch this evolve! The rounded ends on the inwhale spacers will look really nice in a day or two.

Pic 3) Joinery Detail; posted so everyone realises that there's no point jiggering around getting a perfect fit near the bulkheads, because the joint is going to be hidden by the deck anyway, and I'll tidy it up with a fillet in the end. Just make sure that the end grain of these bits is well and truly coated, because water will get trapped here if you store the boat upside down.

Pic 4) Deck beam installed, and ready for that pesky deck to stay in shape!

Cheers,

P (bubbling happily along now)

Cliff Rogers · #97 1st Feb 2006, 11:15 PM

Nice pics, or would be if you had remembered to attach them.

Arhh, they are there now.

bitingmidge · #98 1st Feb 2006, 11:27 PM

Your on a Windows machine aren't you Cliff?

Anyway: Now for that pesky deck! As mentioned above in several places, the 6mm 5ply is bit reluctant to spring into the necessary shape required to give the deck a nice camber.

I've sanded off an entire ply, and it's still pretty springy, so I clamped a deck in place to see what it would look like (Pic 1)

.

Clearly the first six inches was the only bit that was even remotely interested in being bent.

I reckon you must have the patience of Job there Doug!

This calls for a serious bit of strategy (and another jig for you Rowan!) so I cut a few moulds tonight, to hold the deck camber while I popped a couple of coats of epoxy on the underside. (pics 2 &3)

I didn't bother compensating for springback, it's either going to work, or it's not. If it doesn't, I'll be back tomorrow night armed with a roll of fibreglass tape. THEN we'll see who's boss!!!

Cheers,

P

Cliff Rogers · #99 1st Feb 2006, 11:32 PM

Quote:

Originally Posted by bitingmidge

You're on a Windows machine aren't you Cliff?

...

Sorry, is it too fast for your old Mac?

You have an e-mail waiting as well.

deepdug · #**100** 2nd Feb 2006, 07:52 PM

OK, I've taken the seats out and cut the spreader close to the gunwale [there was no way that the screws were coming out].

Now, has anyone any bright ideas as to how I might get enough force to distort the boat about 100 mm at the centre. It is quite stiff. It doesn't complain about the movement but it is very stiff.

I found out that the bottle hydrolic jack from my van will not work in a horizontal position.

Doug

Daddles · #**101** 2nd Feb 2006, 10:47 PM

Quote:

Originally Posted by deepdug

I found out that the bottle hydrailic jack from my van will not work in a horizontal position.

Doug

Then stand the boat on its side so the bottle jack is upright

Richard
yes, I would have tried the bottle jack ... after swearing and other 'salty' endeavours:eek:

I have heard it rumoured that a bottle of rum works very well ... well, you don't notice your failure quite so much

bitingmidge · #**102** 3rd Feb 2006, 12:32 AM

Quote:

Originally Posted by deepdug

[there was no way that the screws were coming out].

Try sticking a hot soldering iron on them for a couple of minutes; that will soften the epoxy on the threads.

Someone in Adelaide bought some 4' Bessey clamps last year, find that person and borrow one, reverse the head to turn it into a spreader.

OR cut two temporary spreaders, one say 50mm wider than the current dimension and spring it into place, then get the next and jam it at whatever angle fits, then gently pursuade the other end into position.

Any pipe clamp/sash clamp that can be reversed will work though.

Cheers,

P
(this time I'm going to glass the underside of the decks - damn that springback!)

Boatmik · #**103** 3rd Feb 2006, 09:35 AM

Quote:

Originally Posted by deepdug

OK, I've taken the seats out and cut the spreader close to the gunwale [there was no way that the screws were coming out].

Now, has anyone any bright ideas as to how I might get enough force to distort the boat about 100 mm at the centre. It is quite stiff. It doesn't complain about the movement but it is very stiff.

I found out that the bottle hydrolic jack from my van will not work in a horizontal position.

Doug

YOu could put the boat on it's side up against a wall.

Or use two struts and two pairs of identical wedges.

Use one strut first. Two wedges at the same end of the strut set up pointing in opposite directions so they provide a flat surface. When out to max put in the second strut and keep going out to max. Then use original strut with wedges one end and a block of wood on hte other.

Keep an eye on the gunwale to make sure it doesn't get an "s" shape.
Keep an eye on the panels around the centre of the boat to make sure they don't go hollow (concave) as you stretch it out.

Maybe go about halfway, put in a temp spreader and take out the jack and let the boat rest in the sun for the day then continue.

You could wrap the gunwales alongside the cockpit with black plastic to increase the heat further. Cut up a garbage bag - dark green would be OK.

MIK

Boatmik · #**104** 3rd Feb 2006, 09:40 AM

Quote:

Originally Posted by bitingmidge

(this time I'm going to glass the underside of the decks - damn that springback!)

Yep - to remove an epoxied fastening - heat up the end with a soldering iron - works like a charm.

I can't tell by you photo but how gruntful is your jig for getting some pressure on the ply edge. Would some lateral timbers clamped under the gunwale with small wedges tapped between them and the deck edge work better

Or start with a new rectangular piece and bend that. YOU could prebend (more than you need - as much as you can get!) with a longitudinal bit of timber with transverse pieces over the top. Gyprock screw the sides of the ply to the ends of the transverse pieces pulling it down bit by bit. Soak it overnight. Dry it off with a hairdryer and then leave it in the sun to dry thoroughly.

BTW - they found out during WW2 (farnborough aircraft research) that it's the heat that does the work - the water is just there to stop the timber from drying out excessively.

But there must be a better way!!! Maybe I can use your workshop next week when I visit to work out whether to change the method or change the design!!!

)

Michael

deepdug · #**105** 4th Feb 2006, 06:53 PM

What a bugger of a job.

The sides of my canoe are as stiff ..... well they needed a lot of force to distort them.

As is usual for a computer programmer I spent a lot more time devising a method than doing the work.

I finally used some pipe clamps and a saw horse. There was very little creaking from the structure and only one alarming thump which was when the filler around the edge of the deck let go in three places.

The gunwale now slopes down quite a bit at the centre but it all looks ok.

As one of the photos shows it now measures 856mm at the spreader.

My current plan is to put a new spreader in, re-fill the deck edge, sand and repair the area from which I removed the seats and to fill those annoying little holes from the butt strap pins. I will then get it back onto [hopefully not into] the water and experiment with various seat heights.

Then I can start on the new seats and the paddles.

I thought that this was going to be a quick project!!

Michael, I live at Lockleys.

Doug