Building a small trolling boat.

[Lurvio]

Hello

I don't know about temperature control other than the guy selling me the resin said I should heat the boat to about 60 deg. celcius after the glassing is done. The summer game a couple of days ago so I don't think the temp is going to be a problem. Night temp seems to stay over 10*C and day temps 20-25*C for the near future.

The local birch ply is good quality. I had not even thought there might be worse kinds in the world. But I had to get some cheap ply (15 mm) for the boiler house a while back and found some Brazilian conifer ply from a local supplier. It was about 30% cheaper than our spruce ply and there was a good reason.

I have no idea what the wood species is but it looks a bit like larch. 5-10 mm year rings and knots the size of my wrist. It was however suitable for the job, the inside wall of a wood chip storage.

The rot resistance is something I'm familiar with birch, I have done some nice looking things out of spalted birch. The thing thats bothering me is that when I looked up Okoume in Wikipedia, the article stated "It is a weak wood with low decay resistance and moderate dimensional stability". I don't mention that to pick on okoume users, but if that can be used succesfully then birch should be too. And yes, I will coat every surface with the resin.

Lurvio

Originally Posted by Lurvio

said I should heat the boat to about 60 deg. celcius after the glassing is done.

He is right! You should postcure the boat (70°C would be better)

The thing thats bothering me is that when I looked up Okoume in Wikipedia, the article stated "It is a weak wood with low decay resistance and moderate dimensional stability". I don't mention that to pick on okoume users, but if that can be used succesfully then birch should be too. And yes, I will coat every surface with the resin.
Lurvio

Do´nt rely too much on Wiki!

Okoume ply is a lightweight and good ply when produced to spec.s.
But, as always in our business it depends.............
..is it really Okoume? Or one of several species which are on the market sold under the same name?
This, for example is NOT Okoume, but trades as such....

http://www.thewoodexplorer.com/maindata/we1161.html

Look here when you are interested in wood species:

http://www.thewoodexplorer.com/maindata/we142.html


Regards
Richard

[Lurvio]

apex1
Thank you for the links, looks like an intersting site. The information could have been organized a bit better for easier comparison between timbers.

Personally I don't think I'll ever use Okoume ply as I have birch available. I am sketching a 23 ft runabout but that is going to be cold molded with spruce with the surface layer either mahogany or oak. But that is going to be some years in the future. Before that I am seriously considering buying the plans for GlenL Tiny Might (or maybe the Cracker Box) and build that maybe next summer.

Lurvio

Originally Posted by Lurvio

apex1
Thank you for the links, looks like an intersting site. The information could have been organized a bit better for easier comparison between timbers.

Not my fault! But when you scroll down to the data it will be more convenient!

Personally I don't think I'll ever use Okoume ply as I have birch available. I am sketching a 23 ft runabout but that is going to be cold molded with spruce with the surface layer either mahogany or oak. But that is going to be some years in the future. Before that I am seriously considering buying the plans for GlenL Tiny Might (or maybe the Cracker Box) and build that maybe next summer.

Lurvio

Definetively not Oak!!!!
It does not like to be glued with epoxy! (one of the rare cases when that happens, Teak is another one)

Though it IS possible to use it, it is not worth the effort and cost for a homebuilder. Let alone the several trial and error cases on the long way to success!

Regards
Richard

[Lurvio]

apex1
didn't say it was your fault.

Thanks for the info. The oak is just something I fell in love with in craft school and I like to use it in furniture. I knew teak has problems in gluein but not about oak, maybe it's only with epoxy? I am using PUR-glue on this small boat and this product seems very good for boatbuilding. It behaves a bit differently than the PU:s I've used in the past. I explained it to some extend in the first couple of posts of this thread.

Lurvio

[Lurvio]

Hello

The first side panel was glued a couple of days ago. The 4 mm ply took to the stern tumblehome twist a lot easier than I had thought, but I should have trimmed the excess of the ply before glueing. I have a feeling it's gonna be a bitch to fair later on.

Pics, testing the placing of cranks and seat...


...glued transom...


...and the first side panel.


I went shopping yesterday, now I have most of the materials at hand. The stain I have to buy next time, I'm going to need it soon. The angle gear provided me a good challence, the bevel gear cogs alone would have cost nearly 80 €. I solved that by doing what others have, bought an angle grinder. It has an aluminium cased angle gear with 1:4 gearing (or near that) and cost me only 20 €.



I also got some deck hardware, a nice looking cleat to the bow and a couple of attachment rings (U-shape welded to a plate) for the stern end. I'll take pics of those later.

Lurvio

[Lurvio]

Hello

No, I'm not dead yet, just been too darn busy with everything else. The missus moved in.

I got a little something done in the last couple of days, two more pieces of side plywood are glued on, one piece still to glue and the sides are ready for finishing. I cut the extra off the pieces before glueing to ease the fairing later on. That also made the bending easier. I got the transom sanded, stained and the first coat of polyester on top. I also coated the frames in the places that are hard to get to after the plywood is on.

I marked the chine and sheer (and side batten) to the inside of the plywood on the first fitting and drilled the screw holes from that side. This way I get the holes in nice straight line and all the pencil marks are hidden inside. Also in the pic can be seen that I cut the joining face at a slight angle to better fit to the curve on the bow.


Gusset to join the two side panels.


The transom in colour.


First ply panel on the port side


I think I screwed up with the side battens, they should have ended about half way between frames #1 and #2 instead of forward of frame #2. Now I have a flattish area on the side around frame #2. It remains to be seen how bad it actually is, but I know it would have looked better with shorter battens. This also resulted in the joining faces of the side ply panels not to fit. I had to plane the joining face of the bow panel a bit concave.

Well, that's all for tonight.

Lurvio

[hoytedow]

'The missus moved in.'

So many boatbuilders have ended this way.

[ancient kayaker]

Don't you hate it when life gets in the way of boating?

[Lurvio]

Yes, life (and work) tends to come in the way of boatbuilding sometimes. But don't you worry about the missus, I tend to pick 'em carefully and keep 'em in a short leash.

L

Edit: Oh by the way, the side planking is on. Now some wood putty, fairing, maybe the first coats on the sides and then comes the bottom.

[ancient kayaker]

Originally Posted by Lurvio

... don't you worry about the missus, I tend to pick 'em carefully and keep 'em in a short leash ...

There is a proper thread for jokes ...

[Lurvio]

Well I ain't joking either, but thats a topic for whole another forum.

[Lurvio]

Hello

Time for some update. I've actually got a lot done since last update.

Last of the side panels glued




Fairing before bottom panels


And fitting the first bottom panel. Second fitting in progress, I drill thru the holes in the ply to the framing underneath and attach screws where needed to bend the ply in shape.


Glue applied to the framing and masking done to protect the wood from glue runs.


And first bottom panel screwed on and waiting for the glue to dry.


Glueing some foam pieces to make the tunnel mold.


I clamped the foam block in place and used the angle grinder to form the tunnel shape to the boat bottom and the foam at the same time. This pic is after painting the mold with PVAc-glue and some wood putty for fairing.


I had a bit of misfortune as the ply sheet I had thought I could use for the last two panels to the bow turned out to be a lot thicker than it should have been. It took me a while to get a new piece of ply. I think the pieces are from the same pack as the original sheet as it has quite similar pattern, just the wave is missing. Good thing is, the thicker ply also was of poor finnish so I'm happy I got some new ply. Here's the second to last panel.


Last piece glued and fairing complete. Just some holes to fill and then the stain.




Stained


I had thought I could save some time and had stained and coated the aft end of the hull earlier so I could start making the tunnel. Of course the stain didn't match the earlier one. I think the reason is I used the same foam(suberlon) piece as before and I should have cut a new one. The newer stained area is a bit darker. Oh well, I'll see what I can do to it, I have a couple of ideas. I'll take the hull to direct sun light tomorrow and see how bad a mess I have made with the stain.

Anyway, here's the hull with first resin coat on, the lighter colour can be seen in the aft.


Darn, that was a long one, I should do this more often.

Lurvio

[hoytedow]

Marvelous!

[Lurvio]

Thank you, Hoyt.