SIB Trailer Build

hippyhunter · 22 September 2014, 22:34

I'm knocking up a trailer for my new SIB, I'll post progress if anyone's interested.

It's a Gemini GRX

hippyhunter · 22 September 2014, 22:40

The trailer it came on would be ok for local launches but I'm Midlands based and either head north to Scotland or south to Pembrokeshire so I want something that I don't have to worry about.

I'm inventing the trailer as I go along so any good ideas will be appreciated!

hippyhunter · 22 September 2014, 22:56

Progress so far....

hippyhunter · 22 September 2014, 23:00

It's a bit of an evening and weekend project when I can fit it between real (paying) jobs.

Has anyone had experience of getting an IVA on a trailer from VOSA?

All the best, Jim

hippyhunter · 22 September 2014, 23:10

It's not another Clicky thread I promise (I hope).

Nos4r2 · 23 September 2014, 04:29

It doesn't look like it. If anything it looks like the trailer will weigh more than the boat .

Peter_C · 23 September 2014, 07:13

OH MY, and I thought "I" overbuilt stuff. Very nice job!

When I built the upright stanchions for my 4.2m SIB, I used aluminum, and welded up only four of them. Two can be seen in the photo below. I reused the single u-bolts, but what you can't see, is the part that fits into the frame channel to keep it from rocking and carries the actual weight to the trailer.

Nice shop setup for manufacturing large steel objects.

hippyhunter · 23 September 2014, 16:38

Quote:

Originally Posted by Nos4r2

It doesn't look like it. If anything it looks like the trailer will weigh more than the boat .

Spot on Nos4r, at the moment it weighs the same as the boat, 100kg

There's a bit more to go on it yet though

hippyhunter · 23 September 2014, 16:51

Quote:

Originally Posted by Peter_C

what you can't see, is the part that fits into the frame channel to keep it from rocking and carries the actual weight to the trailer.

That makes sense Peter.

I like your 'transom saver' and I'm messing about with a home made mk1 version. Do you get much side to side movement with it? I was thinking of an A-frame arrangement to try and reduce movement in the leg.

Also would you recommend a short sloping bunk section to help recover the boat onto the main bunks?

I'm trying to work out angles of straps/transom saver at the back end and it's getting crowded.

Cheers, Jim

hippyhunter · 23 September 2014, 17:02

Couple of the back end.

Two bits of box to support the transom and stop the boat sliding off the back of the trailer. Other pic is mk1 transom saver being invented.

camelgas · 23 September 2014, 17:22

Very nice !.

are you going to get it galvanized ?

I made a transom saver for my sib of a similar type to Peter_c (but made of salvaged materials) and just use a small ratchet strap round the leg and back of the trailer to keep it all snugged up, works well .

Peter_C · 23 September 2014, 17:28

Quote:

Originally Posted by hippyhunter

I like your 'transom saver' and I'm messing about with a home made mk1 version. Do you get much side to side movement with it? I was thinking of an A-frame arrangement to try and reduce movement in the leg.

I would always recommend a transom saver especially with a SIB. Mine does flop side to side, and although I don't really think it will damage anything, it is annoying to watch in the rear view mirror. If I ever built one it would extend up the lower leg, as you have already done to keep it from flopping about.

Quote:

Originally Posted by hippyhunter

Also would you recommend a short sloping bunk section to help recover the boat onto the main bunks?

YES! I cut mine at angles, then sanded them to a nice round over, only because my trailer came with them. If I ever have to build new ones, I will build a stainless bracket to hold a section of 2x6" bunk at around a 25* down angle...or so. It would probably be one of those eyeball builds, which I think you know something about. The bracket could just be 3/16" with a couple strips welded to the bottom for added strength over the bend.

Quote:

Originally Posted by hippyhunter

I'm trying to work out angles of straps/transom saver at the back end and it's getting crowded.

You don't have to tell me about a busy transom! The angle of the tie down straps is not nearly as important as actually putting them on.

What the heck are those uprights at the back for? Seriously overkill, "if" they are just to keep the boat from going backwards.

One thing I would also highly recommend is side bunks or a roller to help guide the boat one in rougher/windy conditions. I prefer to drive the boat on the trailer, IF the trailer gets dunked. I quite dipping the trailer in salt water though after building transom wheels brackets and legs.

hippyhunter · 23 September 2014, 17:55

Quote:

Originally Posted by camelgas

Very nice !.

are you going to get it galvanized ?

Thanks, yep it'll be off to the galvanisers (to add more weight).

hippyhunter · 23 September 2014, 18:21

Quote:

Originally Posted by Peter_C

What the heck are those uprights at the back for? Seriously overkill, "if" they are just to keep the boat from going backwards.

I want to take as much movement as possible out of the transom when I'm towing with the engine on the boat. I'm planning on strapping diagonally backwards from the D-rings on the transom down to the trailer so the transom is pulled tight against the uprights. I won't be so concerned about tube pressure when I'm going down the road.

Quote:

Originally Posted by Peter_C

One thing I would also highly recommend is side bunks or a roller to help guide the boat one in rougher/windy conditions. I prefer to drive the boat on the trailer, IF the trailer gets dunked. I quite dipping the trailer in salt water though after building transom wheels brackets and legs.

They're in the pipeline. I'd prefer not to fit transom wheels so the trailer will get dunked although I've got an idea for preserving my wheel bearings.

One thing I did realise after I made the Neptune's trident affair at the front was that it would be a nuisance to mount a winch if I decide I want one.

Thanks for the advice

Festinghouse · 23 September 2014, 18:27

i built this a few years ago, supported the leg perfectly when strapped down and had the sloping bunks as mentioned

hippyhunter · 23 September 2014, 19:16

Crikey that skeg's seen some action.

Cheers FH, those sloping bunks look like the way ahead.

Festinghouse · 23 September 2014, 19:23

yeah i never did get round to repairing that one, too many rocks around anglesey!

Peter_C · 23 September 2014, 22:07

I have never seen a boat with anything more than a couple of strap tie downs at the stern. You do need to support right under the transom with the bunks. Without those two poles in the back you already won't have any movement as your motor support stand looks solid

Another thought, since you are dipping it would be to completely seal the trailer up, so that there are no holes in it. That way salt can't get to the inside. I might be inclined to temporarily rig something up to pressure test it. Then cut off the fitting, weld it closed and grind it flat.

A winch is a must have...period. Mine got used pretty much every time I dunked the trailer, and even more so when I don't and drag it on.

camelgas · 24 September 2014, 06:40

If the box section frame is welded closed , then galvanizing will most likely distort the chassis.

beamishken · 24 September 2014, 07:28

Galvanising company won't dip closed tubes as they are likely to burst when dipped
Best idea is leave tubes as open as possible to ensure complete coating with zinc.drill high & low drain holes to avoid pooling or air entrapment during dipping