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Breambuster33
05-02-2008, 07:34 PM
Hello guys and girls,
I am building a casting deck for boat.
I am thinking of using brackets attached to the side of the boat to hold it up but i am not sure how to do so.
if anyone wsould now an easy and effective way could you please let me know.
thanks

Outsider1
05-02-2008, 08:03 PM
Hi BB33,

BM's suggestion in the marine ply thread (I have quoted it below) is really the only way to go with a fibreglass boat I would think. I don't think it is really practical or a good idea to be drilling holes through your hull, which is what you would have to do to attach the brackets.




http://www.ausfish.com.au/vforum/showthread.php?t=124243

To give your casting deck something to sit on instead of using the l-shaped brackets, glass some timber pieces to the hull. The casting deck can then be screwed to the timber blocks and it will be far stronger than using the alloy pieces.

Grind the area where the timber blocks will go and hold them in place with car bog. Then glass over the timber blocks and glass them to the hull. 3 layers of say, 450 csm will be ample.

To seal the underside of your ply sheeting there are many ways to do it but the only way a boat builder/repairer will do it (and of course the simplest and most appropriate method) is with fibreglass. One layer of 450 csm on the underside and your done. If you want to get carried away, then flowcoat it too.

Cheers

The V shape of the hull will assist you here. A ply piece cut to shape will be held up to a degree by the hull sloping to form the V. What BM is suggesting is to create a supporting ledge on which the ply piece can rest. This will do two things, 1) provide extra strength to support the casting deck, and 2) help to keep the deck level and steady.

Fibreglassing sounds difficult but it not really if you take your time and work slowly but steadily and follow the instructions. Really it is a like like making paper mache except you use Resin and glass fibre sheet instead of glue and paper mache. There are some handling issues and risks you need to be aware of and it would help to have someone work with you who knows a bit about it, but don't be too daunted by it.

Cheers

DJ

PWCDad
06-02-2008, 07:54 AM
You can also do it with Sikaflex ! Many car panels these days are glued on ...

You would have to fabricate some right angle brackets (angle with be less than 90 degrees because of hull sides) with a decent surface area ...say 100 x 100 mm with a 50mm right angle coming off it.

Attach 8 or so around the area the deck will be ....

Use masking tape for a good edge .... mask off 102mm x 102mm cover the back of the bracket with sikaflex ... push it on til all air has gone and sika oozes from the edges ... use masking tape to hold bracket for the cure time.

After cure ... run a small blade around the bracket next to the tape ... peel off excess sika and masking tape ...voila !!!

Place deck on top .... (ally chequerplate would look the goods) but may have to be braced at the aft end in the centre.... or get a 50mm x 25mm piece of rectangular hollow section in 3mm wall welded to the edge with the 50mm side vertical.

Drill holes through deck and brackets for 316 stainless round head socket screws (so you dont kick your toes on the bolt tops ... use a nyloc nut and washers on both sides ... to stop the galvanic action between the ally and stainless apply durolac ....

You could run the deck close to the hull and seal that right around with sika as well .... hard to get a neat bead though ... unless you do it regularly.

Would not look as good as glassed area all prepped and painted though ....

Regards
PWCDad