cavity fixings for marine use

[surekandoo]

Anyone know if its possible to get s/s cavity fixings for marine use please?

I have to refix a boarding ladder to the stern of my boat which has a double wall with an inaccessible void between. It occurs to me that the old fashion spring toggle fixings would be ideal but I'm concerned about corrosion and subsequent safety considerations.

Any suggestions or alternative solutions welcome.

 

[maxi77]

Anyone know if its possible to get s/s cavity fixings for marine use please?

I have to refix a boarding ladder to the stern of my boat which has a double wall with an inaccessible void between. It occurs to me that the old fashion spring toggle fixings would be ideal but I'm concerned about corrosion and subsequent safety considerations.

Any suggestions or alternative solutions welcome.

My worry is stopping water getting in, but there are these http://www.memfast.co.uk/shop/Vprod2.asp?cat=2253004510
Which I have used.

 

[colvic987]

My worry is stopping water getting in, but there are these http://www.memfast.co.uk/shop/Vprod2.asp?cat=2253004510
Which I have used.

a2's would not be suitable for any length of time, would the fibreglass take that sort of fitting also. i would expect to see them used on a mast section but not in fibreglass. IMHO..

 

[Seajet]

Would it be possible to cut an internal access hole allowing fit of a conventional backing pad & marine stainless fastenings, then put a dinghy style inspection hatch covering the hole ?

 

[PetiteFleur]

My worry is stopping water getting in, but there are these http://www.memfast.co.uk/shop/Vprod2.asp?cat=2253004510
Which I have used.

I've also used these on an ali mast but never on grp - it's too soft but I don't have a better solution for you. I like the idea of the 'toggle' fastener but no idea if available in stainless steel.
Another thought - if you could make an access hole internally could you cover this hole with a standard 'hatch' cover? To make sure the acces hatch holes line up with the bolt holes, position the ladder and drill through a small hole through both skins. This way you could fit a large stainless plate with tapped holes to take the bolts. Better still a long plate to cover both sets of holes. Another idea could be to use 'BIGHEADS' which are large headed screws which could be epoxied in position.
Good Luck.

 

[Momac]

Might this do the job - used with a stainless screw ?
http://www.rawlplug.co.uk/index.php?option=com_content&task=view&id=83&Itemid=34

 

[Jcorstorphine]

Found SS toggles in US

If you follow this link and watch the video it shows a neat solution BUT it is from the US

http://www.toggler.com/products/snaptoggle/overview.php

They are available in SS

 

[surekandoo]

Many thanks for all the replies.

I have used rivnuts on the mast but would not consider them suitable for use in fibreglass.

The rawlplug option looks quite good but I'm concerned that the threaded insert is brass & might be subject to corrosion and de-zincification in a marine environment.

 

[SHUG]

I think there is a technique where you take out a core with a hole cutter and then replace it with glassfibre. The fixing then goes into the solid glassfibre

 

[surekandoo]

I think there is a technique where you take out a core with a hole cutter and then replace it with glassfibre. The fixing then goes into the solid glassfibre

I'd thought of this, but it's a vertical surface, so retention of the epoxy in place might pose a problem.