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Warren (Staff) - 11/21/2019 2:37:12 PM

Do you mean bond on ones?  We sell a small selection of the bigHead Bonding Fasteners, which are a good choice.  However there are more types on the market should you need something different. 

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Rodrigo Jimenez - 11/21/2019 11:18:10 PM

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Hanaldo - 11/21/2019 10:16:56 PM

You can do a secondary bonding application with the bighead fasteners as well, they don't need to be built into the laminate during lamination. Just use a suitable structural adhesive.

You could use Camlocks aswell, but any of those mechanical grip type fasteners arent great for composites and are more likely to fail over time. The Bigheads would certainly be my choice.

Yes but these insert are for an engine mount I need pullout strength and with threaded inserts i believe i will get more, 2 top engine mounts into the monocoque bulkhead from engine cylinder heads, there are currently proper inserts but for another engine so the main stud (12-14mm) does not align with the original thread so i have to place a new one and some more around, obviously i will reuse all present inserts, base on the research a did the best solution i came is to bonding kobserts with coarse thread, concerns is i will not get the proper bonding gap,
i will tap instead of machine so thread may come out not so smooth.
it will be better with self thread inserts like for hard wood ?
in the article attched pull out on kobserts of m8 broke bold before

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f1rob - 11/27/2019 8:18:25 PM

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Rodrigo Jimenez - 11/21/2019 11:18:10 PM

+x

 

Hanaldo - 11/21/2019 10:16:56 PM

You can do a secondary bonding application with the bighead fasteners as well, they don't need to be built into the laminate during lamination. Just use a suitable structural adhesive.

You could use Camlocks aswell, but any of those mechanical grip type fasteners arent great for composites and are more likely to fail over time. The Bigheads would certainly be my choice.

Yes but these insert are for an engine mount I need pullout strength and with threaded inserts i believe i will get more, 2 top engine mounts into the monocoque bulkhead from engine cylinder heads, there are currently proper inserts but for another engine so the main stud (12-14mm) does not align with the original thread so i have to place a new one and some more around, obviously i will reuse all present inserts, base on the research a did the best solution i came is to bonding kobserts with coarse thread, concerns is i will not get the proper bonding gap,
i will tap instead of machine so thread may come out not so smooth.
it will be better with self thread inserts like for hard wood ?
in the article attched pull out on kobserts of m8 broke bold before

What chassis is it in ?? And how much are your positions out in x an y plane ??
If it's a proper chassis you probably have ali inserts in there that are tapped.
Make a threaded ali plug an screw it in with 648 an re drill an tap in the right position.
The problem you have is as you go higher up the formula the original inserts will be more pocketed for weight saving so you might not have enough material to do this.
Can you get a drawing of the original insert ?
If you can live with the weight an the increase in wheelbase it's sometimes easier to bolt an Ali adaptor plate (15mm or so) to your bulkhead an re drill an tap the correct hole centres in that.
When you make a chassis there are many tapering an staggered reinforcing plies centred on the engine mounts.
The further you are from your original holes you get the weaker the structure gets.
Myself if I didn't have any other way I would use a top hat bobbin so you have both skins in compression an hou spread the load
Your threaded insert goes in your counter bore an your either threading a bolt into it or more likely an engine stud.
Several other ways but would need to see pictures of the tub an inserts involved