Reply
 
Thread Tools Search this Thread
 
Old 25 August 2010, 15:42   #11
Member
 
Country: USA
Town: San Diego
Make: zodiac futura mk2
Length: 4m +
Engine: Nissan 40 plus
Join Date: Oct 2008
Posts: 264
For lightweight stuff the counter sunk head on the bottom of the floor board will be fine, but if you intend to blast about I highly recommend using a pan head bolt with a washer. If you are going to fill the depression anyways why not make it as strong as possible? I pull my auxiliary ten gallon gas tank off my floor regularly. The footmans loop is low profile and fits my web straps perfectly without posing a hazard.



Add a ss teflon insert locking nut on top and you are good to go. I would hate to kick a large ring or an eye nut. I can step on my footmans loop without grief (I ground the bolt flush to the top of the self locking nut).

It's all good, no matter how you go. Much better to tie everything down than try to retrieve it from the sea!
__________________

__________________
kelson is offline   Reply With Quote
Old 25 August 2010, 16:59   #12
Member
 
Country: UK - England
Town: Cheltenham
Boat name: Marlin
Make: Solent
Length: 5m +
Engine: Suzuki DF70
Join Date: Jul 2010
Posts: 46
I would go for as much strength as possible, but I think the wood is only 12mm thick, so using a spade bit to recess enough for a nut and a washer on the underside wouldn't leave much wood left to provide support. I'm concerned it might break out under strain.

What thickness is yours, Kelson?
__________________

__________________
jimbojambo is offline   Reply With Quote
Old 26 August 2010, 11:12   #13
Member
 
Country: USA
Town: San Diego
Make: zodiac futura mk2
Length: 4m +
Engine: Nissan 40 plus
Join Date: Oct 2008
Posts: 264
My Futura has two forward wood floorboards that are 1/2 " (12mm) thick. The recess I cut with the spade bit is just deep enough to allow me to cover a thin panhead bolt and washer with the resin and fiberglass strand mix. Technically it is a panhead slotted machine screw. There is plenty of plywood left. The machine screw and washer are much less likely to pull through, even with the wood removed, than a small flat head machine screw in a counter sunk hole. You have to use a pretty small bolt or screw to go through the footmans loop openings. The self locking nut goes on top not on the bottom in the floor. I ground down the excess machine screw length so it isn't protruding. The footmans loops and nuts are fairly low profile, you can step on them and it's isn't a big deal. I use four footmans loops with two straps to hold down a ten gallon gas tank on my bow. I have had to throttle hard to get up and over a head high almost breaking wave. My console base cracked, but the tank stayed put.
__________________
kelson is offline   Reply With Quote
Old 26 August 2010, 12:09   #14
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
How about using a SS carraige bolt from the bilge upwards? Nice smooth round head shouldn't cause any wear problems.

jky
__________________
jyasaki is offline   Reply With Quote
Old 29 August 2010, 04:23   #15
Member
 
Country: Finland
Town: Helsinki
Boat name: SR 5.4
Make: Avon
Length: 4m +
Engine: Toh1 3,5 Yam 90/2S
Join Date: Oct 2009
Posts: 896
How about increasing the thickness of the floor partially by epoxy gluing piece's of plywood on top of the floor? That way you will have more material to work with, even possibility to use screws only. Need proper preparation to be strong though.
__________________
fun on a boat is inversely proportional to size...sort of anyway
C-NUMB is offline   Reply With Quote
Old 29 August 2010, 11:29   #16
Member
 
Country: UK - England
Town: Cheltenham
Boat name: Marlin
Make: Solent
Length: 5m +
Engine: Suzuki DF70
Join Date: Jul 2010
Posts: 46
Hello all,

All done now - I ended up buying a pair of these: http://www.screwfix.com/prods/36070/...-8mm-Pack-of-2

I took the advice, and decided 1 M6 countersunk machine screw going into an eyenut was going to be a bit of a concern, so using the eye plates (each with 4 holes) - I could use the same technique but have 4 times the strength.

I used my calipers to measure the floor - and it's actually only 10mm (9mm ply + fibreglass [?] coating. Recessing into this without building up the floor was going to be a bit close.

All good now - went for a trip out today and they're spot on (and very useful!!)

Thanks for all the help
James
__________________
jimbojambo is offline   Reply With Quote
Old 31 August 2010, 10:13   #17
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,610
I was about to suggest a couple of lengths of yacht "block carriage" track - use multiple smaller thru' bolts to haold it don, the carriages (no block version) can be moved to suit whatever you are or aren;t wanting to hold down, , and the load is shared by numerous bolts rather than just one or two.

I suspect the price may be the down side!
__________________

__________________
9D280 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 01:39.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.