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Best way to add bolt threads in the board for the mast when building board?

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omg
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Best way to add bolt threads in the board for the mast when building board?

Postby omg » Tue Sep 18, 2018 7:10 am

Thinking of making a pocket board, but what's the best way to attach the mast in to board when I don't want to have through the board bolts & nuts but have the mast bolts threaded to the board, please?

Thanks very much! :thumb:

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby faklord » Tue Sep 18, 2018 8:53 am

I’ve used these with success.
http://www.easycomposites.co.uk/#!/tool ... Blind.html
Inserted from top of board. They can even be used as a retrofit. The fact that they stand slightly proud doesn’t matter if you cover with deckpad.

I expect if you look around you can find them a bit cheaper.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby TomW » Tue Sep 18, 2018 6:33 pm

Been looking for those!! And I buy stuff from easy composites. A great company.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby TheJoe » Tue Sep 18, 2018 7:46 pm

http://www.snowboardmaterials.com/index ... ng-inserts

These are what I use. I use poly urethane to hold them in place. I do make a channel from insert hole to insert hole to help hold them in a little better.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby RichR2 » Tue Sep 18, 2018 7:55 pm

Try snowboard/ski/kiteboard inserts http://www.snowboardmaterials.com/index ... ng-inserts
Drill an abs plate to pass these through then glass bubbles and resin to fix into a routed hole in your blank. Then glass your blank as normal.
I use these for footstrap mounts but should be ok for foil mount as they were used on the foil plates on shinn el stubbo boards

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby RichR2 » Tue Sep 18, 2018 7:59 pm

Thinking about it, you would probably need a large plate to insert them into to spread the load from the foil plate. Not done it, but just a thought.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby tmcfarla » Tue Sep 18, 2018 8:50 pm

omg wrote:
Tue Sep 18, 2018 7:10 am
Thinking of making a pocket board, but what's the best way to attach the mast in to board when I don't want to have through the board bolts & nuts but have the mast bolts threaded to the board, please?

Thanks very much! :thumb:
I just drilled holes into core and epoxied inserts in place, then several layers of carbon fiber over, and drilled out carbon once cured. Holes were somewhat over sized. Core material is high density foam, not sure how well this would work with softer foam. Has been holding my foil on for maybe 30 sessions without any sign of weakness (strapless only, and I’m pretty light).

I used 316 stainless steel inserts, which were really hard to find in metric sizes (I eventually found a user on this forum selling them, thanks downunder). Anyone have experience using 304 stainless? Those are easier to find but I was worried it would corrode over time.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby junebug » Fri Oct 12, 2018 12:34 pm

I’m going to be building a basic wood foil board made out of pawlownia glassed 6oz top and bottom.

I’m going to use stainless t-nuts for the foil mount inserts. Dumb question, probably, but should I put the t-nuts in before or after glassing? If before, I would assume I’d need to cover the female end on the bottom with tape or something similar to keep the epoxy out of the female channel of the nut?

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby faklord » Fri Oct 12, 2018 1:20 pm

junebug wrote:
Fri Oct 12, 2018 12:34 pm
I’m going to be building a basic wood foil board made out of pawlownia glassed 6oz top and bottom.

I’m going to use stainless t-nuts for the foil mount inserts. Dumb question, probably, but should I put the t-nuts in before or after glassing? If before, I would assume I’d need to cover the female end on the bottom with tape or something similar to keep the epoxy out of the female channel of the nut?
I would put them in after glassing (glass will help spread the load and reduce possibility of pulling through the soft wood). Ideally then add a local glass patch on top.
I used this method on a board with foam core + carbon skin. Seems to be holding up ok.

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Re: Best way to add bolt threads in the board for the mast when building board?

Postby downunder » Fri Oct 12, 2018 3:03 pm

tmcfarla wrote:
Tue Sep 18, 2018 8:50 pm
omg wrote:
Tue Sep 18, 2018 7:10 am
Thinking of making a pocket board, but what's the best way to attach the mast in to board when I don't want to have through the board bolts & nuts but have the mast bolts threaded to the board, please?

Thanks very much! :thumb:
I just drilled holes into core and epoxied inserts in place, then several layers of carbon fiber over, and drilled out carbon once cured. Holes were somewhat over sized. Core material is high density foam, not sure how well this would work with softer foam. Has been holding my foil on for maybe 30 sessions without any sign of weakness (strapless only, and I’m pretty light).

I used 316 stainless steel inserts, which were really hard to find in metric sizes (I eventually found a user on this forum selling them, thanks downunder). Anyone have experience using 304 stainless? Those are easier to find but I was worried it would corrode over time.

You are welcome. :)


It is simple really, 304 bolts will corrode in no time and that’s easy to prove. Anything in 304 is NOT marine type SS.

Actually, I replaced all bolts on my Chinese HF with 314.

GEt the magnet and North straps bolts, they are 316, magnet does not work on them.

Depending on a batch, my SS inserts are 314 or 316.

D.

PS

SS inserts must go in just before glassing , with a fiberglass cloth patch to support them, ie 5x5 cm. Basically a patch with a pencil made hole in fabric, to put the insert through. Or risk pulling it out :( bigger the patch, better - sort of bigger surface area.
Sure, if using a PU that’s another level...

No pulled insert yet by customers on my builds.

2.75 Pounds each + VAT? Insane....That’s AU$5 or more...the Word Has gone mad.
Last edited by downunder on Fri Oct 12, 2018 3:23 pm, edited 3 times in total.


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