How should bombard sit on a trailer?

[Nolandandallsea]

Just purchased a new carpeted bunk trailer for my bombard 380 and need advice on the correct set up please.

Should the bunks be positioned under tubes or under the boat more where floor meets the tubes?

I appreciate any advice from you experts.

Thank you

[Max...]

I don't think having them on the tube/floor transition is a good idea. I'd want much longer bunks to support the length of each tube.

[Nolandandallsea]

Thanks for your reply.. so do you mean that the bunks should sit flat under the tubes as much length of the tubes as possible?

The trailer is adjustable so I can ensure the tubes are well supported and will sit flat on top of the bunks.

I thought I read somewhere that the bunks should sit in the groove of where the floor meets the tubes but I'm new to this and wasn't sure!

Thank you.

[jeffstevens763@g]

just setting up a sib trailer defo what max has said personally i like a bunk under the keel too.
could i ask what you think of the aerotec's build quality etc i was looking to buy a bombard c3 but the weight of the areotec is less than half of the c3

[chriswood]

Hi. Having the bunks supporting the area where floor meets tube is something I have heard a few times. I've got a bunked trailer but the bunks are much wider than yours so the tubes sit on the bunks. This does allow the boat to bounce a bit when trailering so contact with a more solid area is probably a better setup.

I would say that with your set up as the bunks are narrow adjust the bunks so they sit in the area where the floor meets the tubes. Unless you make them wider I don't think they are wide enough to give enough support if you position them under the tubes. Just out of interest does the trailer have a transom support?

[chriswood]

Sorry I've just seen in the photo you have a transom support.

[Max...]

It depends if you are transporting with the engine on I guess as to how important this is (without the engine there is very little weight there) but putting stress on the point where the floor and tubes join is not a good idea on a SIB I think. Best to support the floor and tubes with long angled bunks as well as the 'keel'. If carrying with the engine on I would definitely want a support under this too on a SIB.

Re' build quality - IME the Aerotec is very well made and certainly superior to the regular Zodiac SIBs (ie 3.4m Fastroller etc), there seem to be less reports of glue failures too after 10 years or so.

[Max...]

Pic of a trailer here I had.

[jyasaki]

Originally Posted by Max...

I don't think having them on the tube/floor transition is a good idea. I'd want much longer bunks to support the length of each tube.

Disagree (with the former point.) I think the best spot would be right there - that's where the floor edges are in contact with the fabric bottom, so you get solid support without stretching the floor material. At the floor/tube join, you are supporting the only rigid part of the structure (aside from the transom, which should also be supported); having the bunks further out means the tubes have be solidly inflated to hold the boat up (which would not be ideal if you have a burst tube but still need to get the boat home.)

As far as the length, most of the weight will be towards the back (usually), so that's where you need the support.

On my SIB, the bunks ran from the back, about 3/4 of the way forward, and extended several inches behind the transom. A single center bunk at about 1/3 back supported the keel, and a bow stop (basically a bunk mounted upright) located the front of the boat at the winch post.

jky

[chipko]

I would also agree with jyasaki.
Bunk support on floor right next to tubes, angled to floor profile, and extending under to support transom. Would keep keel clear of any cross supports. Not too worried about bunk length as long as min. 2/3rds boat length. Ideally tubes and floor should only be inflated to say half pressure when out of water/towing to allow for pressure increase in sunlight/high temps (we should be so lucky). More important to support transom and floor interface especially if outboard mounted - tubes are light and will support themselves. This configuration will also help centre boat on recovery from water if applicable.

Nice trailer by the way!!

[The Gurnard]

Originally Posted by Nolandandallsea

I thought I read somewhere that the bunks should sit in the groove of where the floor meets the tubes but I'm new to this and wasn't sure!

Thank you.

I believe the recommended way for supporting a traditional SIB with a solid floor is as Jyasaki describes. The reason for that is... the bunks then support the edge of the internal floor which is heavy. My own SIB is supported this way and the boat is 10 years old and been towed thousands of miles with no issues at all. The boat must weight close to 150kg with the amount of junk I carry in it.. but I don’t trailer with the engine on the SIB so dont support the transom..the bunk is around 6" short







Sorry... but I have no idea how an aerotec should be supported though.. its a different boat entirely from a solid floored SIB. There is no heave floor edge to rest on the bunks.



As Chipko says... its a VERY nice trailer ..im sure it is well up to the job..regardless how the boat is supported.

[kaman]

If it were my set up I would be looking to get as much of the underside of the Sib supported by the carpeted bunks as possible - most probably look at adding a wider strip of carpeted wood on top of the existing bunks to achieve this and adjust them to bridge support across the area between the tubes and inflated floor.
I would also give consideration to beefing up the keel support.

On my trailer my keel is supported by a plank of wood which has been shaped with wooden off cuts to the rough shape of the keel.
It has been padded and wrapped in carpet to support a fairly sizable length of keel.
As mine has an aluminium floor my bunks support the edges of floor.

[kaman]

Just looked at your pics at top of the thread again.
Didn't realise the gap between tube and inflatable floor was as dramatic. My Honwave is practically flat by comparison.
Cancel trying to bridge the gap between floor and tube.
I'd go for just supporting the tube with a wider bunk - and fashioning something more substantial to support the keel.

[Northern Pike]

I would put those bunks right at the joint, where the floor meets the tubes. That way they are supporting both the floor and the tubes. Then I would put another pair of bunks on the outside of the tubes for additional support. That's what I did.