Can anybody please tell me the position of the C. of G. of a Seal 22 on the fore and aft axis? I need to know urgently for fitting a two wheel trailer.

On my Sinbad (which should be very similar to the 22) it was about halfway along the keel bulb. I used to dry sail off a launching trolley and the axle was about 2/3 the way back along the keel bulb which gave a slightly excessive nose-weight on the hitch of my Volvo (good for traction on weedy slipway!)

Just seen your post...

With 800lbs, or 33.3% of the 2,400 lbs unladen displacement of a seal 22, concentrated in the keel, which is near as damnit midway between bow and stern, Geoff’s advice to start with the axle about #8532; of the way back along the keel sounds a good starting point.

But, at the risk of stating the obvious, the correct position of your boat on its trailer will be unique to your boat, your trailer, and where you stow the equipment fitted/carried on both, and can only be determined by trial and error, so you must be prepared to move the axle fore & aft on the trailer chassis until you achieve the correct nose weight ["borrow" the bathroom scales for this, & go for the maximum trailer nose weight allowed in the manufacturer's towing data for your car].

If you don't want to /can't shuffle the boat on/off its trailer whilst you adjust the axle, a jack and blocks will allow you to lift the weight off the wheels whilst you do so.

Before you start, bear in mind that the position of various items of heavy kit can make a big difference to the C of G, eg trailer mounted spare wheel? docking arms? outboard engine on/off? full/empty outboard fuel tank(s)? and above all else, where you stow the heavy steel rudder & solid timber rudder stock of a Seal 22 [you are going to remove both for trailing, aren’t you?], so decide what you are going to stow where before beginning to set the axle position.

Oh, and do get down on your hands and knees, check the combined maximimum load bearing capacity of your two trailer tyres, then take the whole fully laden outfit to your local weighbridge, and discover whether or not the tyres supplied with the trailer are actually man enough for the job! In my bitter experience, not all trailer manufacturers fit tyres rated to carry the gross capacity claimed for the trailer...and there is nothing more disconcerting than being overtaken by one of your own trailer wheels...[been there, done that, got the T-shirt..]

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Geoff & Geoff

Thanks for the info. What GVW and carrying weight do you reckon is right for the Seal?

Michael

Michael,

Starting from your unladen displacement of 2,400 lbs [or 1090 kg in today's language] you need to decide whether you will strip everything off the boat before towing [least weight = least cost trailer but most hassle] or whether at the other extreme you want to be able to tow to/from a holiday location with not only all the boats normal equipment aboard, but also full tanks and all your own personal gear.

Don't forget that John Baker's original brochure weight [1090 kg] would not have made allowances for modern equipment that you might take for granted like Sprayhood, Furling Gear, etc. and extras like a toilet, etc. let alone the engine!

So add up the weight of everything that you want to be able to leave/put in the boat, add a margin of at least 25% of that figure [it's amazing how much storage there is in a Seal 22 and how much stuff a family can bring aboard...], add it to the 1090kg, and now you have the load that the trailer must be able to carry.

Just to make life difficult for you, trailer manufacturers often describe their trailers by their Gross capacity, eg 1500 kgs, without always specifying the Net capacity, which is the available capacity after deducting the weight of the trailer itself [after all the trailer axle and tyres have to carry the weight of the trailer as well as that of the boat]. So if a 1500 kg trailer weighs 250 kg itself, then it can only carry a load of 1,250 kg. And if you carry a spare wheel on the trailer, or you fit a steel keel channel to an existing trailer, that is all extra weight that has to be taken into account.

It's also worth picking the brains of long established & reputable boat trailer manufacturers like De Graaf [Surrey], SBS [Woolverhampton] and RM [Hants], who are likely to have supplied trailers for Seal 22s in the past. RM Trailers certainly have [including a Roll On Roll Off], and the owner, Richard Gifford-Hall, is - or was in 2007 - himself the owner of a trailed Parker 27 or 275.

if you have any other questions, feel free to call during the day or early evening - my number's in the Directory.

Geoff Sheddick

If you would like to have a chat about trailers & trailing, give me a call - it's a lot faster & easier than email - my number's in the Directory

Geoff Sheddick

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Geoff

Thanks for the advice. The trailer I have has a plated GVW of 1700 kg and a carrying capacity of 1480, so I am probably OK if careful. I will certainly check the tyres as you suggest. The only mods I will have to make to the trailer will be a keel channel, longer hull support posts and possibly an upward extension to the winch post. I have made a keel channel out of timber previously for a similar boat but might go for metal this time.

I will phone if I get stuck.

Michael