Type XXI 1:32

[tompinnell]

Re: Type XXI 1:32

Design back for the Fumo transmitter I am very pleased can't wait to get it now, Once again this has been done by phd-design-etchings.co.uk yet again a big thank you to Peter

[tompinnell]

Re: Type XXI 1:32

Hi, need a bit of help how do I keep the 2 halves together? I tried a strip on the inside but because of the curvature of the hull it won't work just need some help with how others have over come this problem cheers

[Guest]

Re: Type XXI 1:32

You have to make the halves interlock in some way. Peg it with dowels, or you can make interlocking dowels.

Being a polyester hull and also very large it will tend to move a lot. Epoxy hulls are far less prone to this, but the cost is considerably higher especially for large boats, so it's rare you'll see it used on bigger boats.

I prefer radial separation of the hull points as it keeps the hull halves locked together, and where the break points are, the hull is very stoutly supported by bulkheads.

[JWLaRue]

Re: Type XXI 1:32

I need to find (or take) some photos, but for a hull where the join is on a curve like the Type XXI, I use a variation of dowels which I find easier to do which is what I call "tab & pocket."

The upper hull has a series of (usually fiberglass) tabs epoxied to the inner surface such that the tab protrudes about 1/2 of an inch (12-13mm). The tab is about a 1/2 inch wide and typically at least as thick as the hull itself. The lower hull has a series of matching pockets epoxied to its inner surface with the top of the pockets even with the edge of the hull. The pocket is sized to match the dimensions of the tab so that there is no 'play'...it holds the upper and lower in close alignment.

-Jeff

[bwi]

Re: Type XXI 1:32

Hi Tom,

I have also tried the use of a strip on one side, that did not work at all (in my case the thickness of the hull halves differed).

What worked for me:

I cut the strip in parts and alternating clued them to the upper and lower hulls.





I made the index lips out of polyester resin and 2 layers of 300gr fibreglass cloth. I took over Davit Merrimen’s idea to make them the way I did. First I attached some wax paper to the hull i.w.o. the indicated cut lines. On top I laid-up the fibreglass so the hull shape is exactly transited to the fibreglass. After curing the wax paper was removed and after trimming the fiberglass, you remain with very nice and easy to install "hull shaped" index lips.



My model (not yet completed) is only 30” but it might work also for you.

Grtz,
Bart

[tompinnell]

Re: Type XXI 1:32

Thank you Subculture, Jeff and Bart, I have taken all of your ideas on board and this is what I'm planning on doing. I'm putting a strip on the inside where the cut line is this time it's much thinner so seems to be working much better. I have made some bulkhead templates to ensure a good fit needs a bit taken off and added here and there but they are temporarily tacked in place. Once correct I will bond them into the hull with cross braces to add a bit of strength into the hull the 2 centre bulkheads will support the module once finished. The centre bulkheads will be split in two with a cross bar so I can adjust the hull if it's pulling out of shape will use a ball joint from RC cars on both ends so it's easy to remove. In the top part of the hull will use same method so should be able to close the gap between both halves. I will then hold the halves together using a few pegs and cups along the sides like you have suggested. Ordered the deck and radar so looking forward to getting those.

[tompinnell]

Re: Type XXI 1:32

Got the deck back from phd-design-etchings.co.uk I was very very pleased, spent a few hours fixing deck to the hull and joining both halves now need to concentrate on the rear of the hull as I have no planes, rudder or vanes