Reply
 
Thread Tools Search this Thread
 
Old 22 February 2012, 16:59   #1
Member
 
Country: UK - England
Town: Solent
Make: Phantom 21
Length: 5m +
Engine: Mariner 200hp V6
Join Date: Feb 2008
Posts: 138
Structural query about the new trailer for my Picton 170 GTS.....

I'm 99.9% of the way there but just need someone to reassure me that 80mm x 40mm x 3mm (wall) of mild steel box section will be sufficient for the new braked axle roller coaster trailer I'm building for my Picton 170 speedboat? I'm also planning to run some 40mm x 40mm x 2mm (wall) mild steel box section along the top to help with the longitudinal forces.

The axle is rated to 1300kg so won't be putting any more than 1000kg on the frame at most. Having had a look at any boat trailer I've come across recently, it seems that for the most part that 80x40 is a popular choice.

Any thoughts?

Also, any thoughts about whether or not its best for each set of rollers to tilt freely on the beams as well as the beam swinging??

Thanks.
__________________

__________________
Jonny2488 is offline   Reply With Quote
Old 24 February 2012, 15:58   #2
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
Something like this, with the double outriders, but single axle?





If so, then 80x40 will be fine.

Also, IMO you need the rollers to be able to pivot, on the cradles, to enable self aligning and gentler on your hull. Like this:

__________________

Trailer Guy is offline   Reply With Quote
Old 24 February 2012, 16:39   #3
Member
 
Country: UK - England
Town: Solent
Make: Phantom 21
Length: 5m +
Engine: Mariner 200hp V6
Join Date: Feb 2008
Posts: 138
Thanks for those photos Trailer Guy. Yes just like the first photo, but like you say, with one axle. Looks like they've gone for 80x40 for the lower part of the chassis and 60x40(?) for the upper part? I don't need to go as heavy duty as that and am planning 40x40 with a 2mm wall for the upper part. That should be sufficient I feel.

Good point about the rollers. Some swing beams I've seen just have the roller assemblies fixed so that the only movement the roller has is in the transverse direction. But I guess having each assembly pivot on the beam itself adds to the flexibility. As it's a small boat, think I'll go for 2-3 pairs of rollers each side at the back and 2 pairs at the front, so it will look a bit different to the layout you've got there. Should hopefully be able to get away with just the single point pivot between the swing beam attachment bracket and roller arm assembly. Planning to "U-bolt" some keel rollers to the beams as well.

Do you have any pictures for the mechanism that fixes the swing beam to the chassis at all mate?

Thanks for your input, much appreciated.
J.
__________________
Jonny2488 is offline   Reply With Quote
Old 25 February 2012, 05:28   #4
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
I should imagine so. I'll dig some out for you.
Trailer Guy is offline   Reply With Quote
Old 23 April 2012, 05:01   #5
Member
 
Trailer Guy's Avatar
 
Country: UK - England
Town: Hampshire
Boat name: Altea 2
Make: Narwhal
Length: 5m +
Engine: 90 Mariner
Join Date: Aug 2011
Posts: 855
apologies for the delay in the pictures, it slipped my mind if I'm honest. Anyway, here's the pivot beam assembly:

pivot pin, that fits on the chassis:



with swing arm fitted:



and fitted to a trailer:

Trailer Guy 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 17:56.


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