What do you call this type of bolt?

[burgundyben]

I've seen some bolts that have a flat square head, the head can be recessed into the top face of a piece of plywood, then the ply covered in teak decking. Say the bolt is M8 and the head is 20mm square, with small holes so you can put a screw in to stop rotation.

The result is a teak cockpit sole panel that can be bolted into place form underneath with all the fasteners hidden from above.

What do you call those bolts and anybody know of a supplier?

 

[DannyB]

Square headed bolts or cropped bolts, Amazon have them http://www.amazon.co.uk/s/?ie=UTF8&...vptwo=&hvqmt=e&hvdev=t&ref=pd_sl_1vgrw6vmgj_e
but you can probably get them cheaper from any fastener supplier.

Just a thought, for what you want to do why not just use coach bolts? They have a square on the end of the screw which would pull into the plywood and stop it turning, then you would just have to recess the top sheet to accept the dome head.

 

[Poignard]

I used these on my boat :

http://www.ccfasteners.com/cgi-loca...=240&cart_id=c518dfd0812a3594ba0a0ebd5d1cd089

I bought them from Anglia Stainless ltd

http://www.angliastainless.co.uk/marine

 

[Freebee]

mention of the large head and anti rotation screw are they something like big head fasteners; http://www.bighead.co.uk/english/products/index.html

 

[burgundyben]

mention of the large head and anti rotation screw are they something like big head fasteners; http://www.bighead.co.uk/english/products/index.html

Perfect. Thank you.

 

[Dave100456]

mention of the large head and anti rotation screw are they something like big head fasteners; http://www.bighead.co.uk/english/products/index.html

Good product, thanks

 

[GrahamM376]

An alternative is to use "T" nuts with a bolt from below.

http://www.screwfix.com/p/easyfix-4...fYFIZThLrgqqjXIKgjjHZKDyK9s3PE4Yu2xoCtGDw_wcB

 

[Boo2]

An alternative is to use "T" nuts with a bolt from below.

http://www.screwfix.com/p/easyfix-4...fYFIZThLrgqqjXIKgjjHZKDyK9s3PE4Yu2xoCtGDw_wcB

If you can find tee nuts made from 316 stainless then they will be fine but those plated ones rust in no time at all from my experience of the ones I used on my engine compartment front cover.

Boo2

 

[Poignard]

If you can find tee nuts made from 316 stainless then they will be fine but those plated ones rust in no time at all from my experience of the ones I used on my engine compartment front cover.

Boo2

You can buy them, as I have done.

I can't remember from where but they're out there.