Adjustable deck layout

[diver 1]

Hello

Moving on from a past thread -

I thought I'd post about this as its been a great find for me and helped me achieve what I wanted from my rib in terms of being able to have easily interchangeable deck layout without using loads of silkaflex and self tapping screws with inevitable mess and risk of screws pulling out as holes get worn.

I've decided I wanted options for fitting a) a heavy duty diving bottle rack, b) a home made bench seat for when I take my 1 year old out, c) a second pair of double jockey seats and d) the option of a clear level and uncluttered deck for general fishing etc

I didn't want prominent fixing points that I might trip over of stub toes on. I wanted something strong and permanent that wouldn't corrode or risk compromising the deck. I didn't want water leaking into the deck cavity either.

I ended up sourcing some M10 Self Tapping 316 Marine Grade Stainless Blind Inserts from Technifast. I discussed my requirements with Technifast they were really helpful, can't recommend them enough.

I've fitted them to suit all possible layouts I might need.

Simple to fit, mark out the hole positions carefully, drill 12mm hole, fill hole with Sikaflex or expoxy resin to seal cut edges of ply, wind a M10 bolt with a lock nut on it into the fixing, then using a normal 17mm deep socket simply screw the fixing down into the deck until flush. Then use a spanner to release the locknut and unscrew the bolt. Baby wipes are great for clearing up inevitable expelled sikaflex!

See pictures attached.

[diver 1]

When the fixings aren't in use I screw in M10 nylon grub screws to stop the threads filling up with dirt and debris.

Can also fix eye bolts for securing spare fuel containers, etc etc

I must admit I'm quite pleased with the result.

What does anyone else reckon?

[jeffstevens763@g]

Great idea mate and works very well I have done the same on my Ali deck bit different with mine you drill the hole put the insert on the gun then in the hole works like a pop rivit gun so they are just 1 MM proud.

[slate1234]

Nice idea could I ask where you got the fixings from please.

[diver 1]

From a company called Technifast. They have an Ebay shop here

http://stores.ebay.co.uk/Specialist-Marine-Fasteners

[toonpirate]

Great idea !

[Phil M]

I have some holding my A-frame front bolts on. They have lasted well but fitting procedure and deck condition are critical when it comes to their ultimate strength. To make sure, I epoxied mine in when fitting but if your deck is suspect, they will pull out relatively easily.

Phil M

[jeffstevens763@g]

on my old rib it had inspection hatches fitted where the A frame bolts were so an easy install, the good thing with the ones on mine are they expand underneath so cant pull out
not sure if they make them long enough to work on 20 mm ply though.

[Pikey Dave]

When I specced my current boat I had fixings glassed into the deck for the Ullmans & 2 additional single jockey pods. I had a waterproof GRP box made up that picks up the fixings for the 2 rear "guest" seats, so I can have:-
2 Ullmans + space, handy for when there's just 2 of you & for fishing, this is our usual config.
Or
3 or 4 seats in total
Or
2 Ullmans + storage box. The storage box sits on quick release brackets that allow it to be easily removed from the boat for camping trips, picnics etc. The storage chest is waterproof, so can be floated ashore if anchored off.
I've also got pad eyes in the bow & rear area + cargo nets for more flexibility.


Lions led by donkeys

[jeffstevens763@g]

sounds just right that Dave the beauty of a new build just how you want it something boat builders should pick up on in my opinion.

[diver 1]

Jeff - yes I did some tests in the workshop on ply and on hardwood. These fixings will pull out if jacked hard enough (I wound a bolt into them against a plate washer and oversized nut). But it's failure of the deck material rather than the fixing - the softer the material the less force required to pull out. The deck on my RC is fine and despite my best efforts not managed to pull one out accidentally yet.

Jeff - can you get your fixings in stainless and what thread size do they go up to?

PD - definitely the right way to go from new for sure. Sounds like an ideal set up. But for a second hand boat glassing new layers and adding hatches into the deck can be a bit time consuming.

[jeffstevens763@g]

ww.ebay.co.uk/itm/112000220123?_trksid=p2060353.m2749.l2649&var=4109 42173860&ssPageName=STRK%3AMEBIDX%3AIT

diver 1 this were i got mine and you need the gun cost £10.00 off ebay not saying its the best and needs a bit more investigating for A2 & A4 but these work the same as pop rivets a bolt is threaded into the gun and the insert when you squeeze up it swells below the deck so can not pull out [ali / steel plate] now for wood it will swell in the hole so causing a force fit bit like a rawl bolt or any mechanical fixing the wood is still the weak point but if you drill a force fit hole you stand more of a chance worth looking into.
we work on lock gates and some times you have only a hole to fit bolts so we use toggle bolts well thats what we call them same principle as the bolt on the small outboard for the trim setting if the toggle is loose you can shake it about and pull back out bit of a faff but works just an idea.
i did get A2
cheers

[jeffstevens763@g]

M3 M4 M5 M6 M8 M10 M12 STAINLESS STEEL RIVNUTS BLIND THREADED NUTSERTS INSERTS | eBay

http://www.memfast.co.uk/
http://www.ebay.co.uk/itm/Stainless-...4AAOxyCepScg15
link not worked sorry try this

blind jack nuts might be an answer

[diver 1]

Jeff - I saw those rivnuts - think you mentioned them in my previous post. My two concerns were finding them in 316 stainless and in long enough lengths to extend beyond the base of the deck so they tighten against the bottom of the deck - like pop rivets they seem to be more designed for thinner sheet metals. I looked for toggle bolts too but couldn't find ones strong / big enough in stainless and what happens when you want to remove them. Also I don't want to leave open deck penetrations that are going to cause water to trickle in to the deck cavity as on my RC its a faff to get it all back out via the drain well / bilge pump then syphon the bit the bilge pump wont suck.

[jeffstevens763@g]

yep i had a good look last night you can get 304 s/s but not seen 316 the best one for your application would be the jacknuts but again without contacting a supplier to fine out the range i only found short length ones [thats the ones on ebay spot on with plastic blank bolts in, allen head low profile] i know there are some deck fastenings available because i have seen them in a boat.its an hollow board fixing used in shop fitting etc there must be a marine application somewhere.ASAP supplies might know or seascrew or even give ribcraft a ring. if i find anything i will post.

cheers

[Pikey Dave]

AFAIK Ribcraft use Big Heads or similar. They are fixed to the deck during production & then glassed in. They can be retro-fitted by grinding away the grp , fitting the fixings & reglassing. They are the dogs danglies of fixings.
http://www.bighead.co.uk/the-original-bighead/


Lions led by donkeys

[jeffstevens763@g]

https://www.fixingsmegastore.co.uk/coach-screws

diver 1 have you thought of 316 coach screws put back in with sikaflex and a rubber washer/o ring when you remove seats etc minimum trip hazard cheap very large thread?

[jeffstevens763@g]

http://www.rivetnut.com/pdfs/RFCI-CD...TA%20SHEET.pdf

here you go 316 stainless M8 23.5 long

[diver 1]

Hi Jeff

Cheers for links. The M10 316 coach screws only start at 50mm long - would be worried about damaging under deck fuel tanks which RC informed me can be as little as 40mm below top of deck. The Rivetnut link states maximum material thickness 3mm?

[jeffstevens763@g]

Bugger see that just got eye on 316 & length wonder why you need 15 MM more length to archive max 3 MM ?

Re the coach bolts I used them on my transducer but I cut them down so they didn't come through I think there better than screws to get in & out if you know your floor thickness no big deal any more bolt through is a waste anyway just a simple fix until you find exactly what you want

Cheers