Yard Trailer Plans

underdog

underdog

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I need to build a yard trailer for my latest acquisition. The boats dimensions
are Loa =32'
Beam = 8.5'
Draft = 4.75 Fin Keel
Weight = 2.9 tons
Has any one a plan of a trailer which would accomodate such a boat
Only need to be able to move the boat about 100 yds so dosnt have to be too elaborate. steering would be a bonus but not essential
Many thanks
 
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Plans for a yard trailer

I havn't got any plans but because no one has answered I will make a few comments.
Simplistically you get some U channel that is wide enough to sit the bottom of the keel into. This obviously needs to be as long as the keel but can be long enough to become a draw bar. You then attach an axle or 2 axles and fit side supports from the axles vertically to provide either support for the hull mid way up or sideways support for the gunwhales.
However the narrow channel will not be so easy to get the keel aligned into. Are you going to float the boat on and haul out on a ramp or crane the boat on? if it is to float the boat on you need a cage around the keel to align the boat above the channel and to be able pull the keel forward against it. I made comments recently about road trailer for fin keel on steep ramps.
However if you are craning the boat on you could use a wide tray to sit the keel on with no side walls. you would need to be able to adjust the side supports to keep the boat vertical if it didn't land on centre line.
The axles are best if you can have a step in the axle (drop axle) (use vehicle stub axles) This will keep the bottom of the keel as low as possible and well below the centre of the wheels. hence the whole boat is as low as possible.
You will probably find the boat is stern heavy. (it may be bow heavy) when sitting on the fin. You need to know in advance if possible or be prepared. Locally on a cradle they just tie the bow and stern down with ropes but this is not good. A cross member on a post under the front of the hull and another toward the stern with a jacks on will enable you to stabilise in the fore and aft plane.
If you make these supports really strong you may be able to jack the boat so the keel comes off the support.(short term) This for maintenance and painting of the bottom of the keel. It is frustrating to not be able to clean and paint the keel bottom. Alternatively you might have several cross members under the keel which have gaps between them and which you can remove one at a time.
Do consider these things as if you design for just strength you may find that getting access to the whole hull and keel very frustrating.
Lastly look at other trailers in the yard and ask the owners about the pros and cons.
good luck olewill
 
The last two I made (without plans) were constructed of 'I' beams. S simple 'H' frame at the front with a timber covered in carpet to take the front of the boat, the tops ended just above the deck to you can tie off on them, also carpet pads on timber on the insides to avoid damage when entering.

The two arms aft were about the same length as the front but are hinged at the bottom with adjustable chains fixed in the centre down low with a gap wider than the keel so it passes between them, hole notches in the steel to make instant adjustments.

At the top of the beam a slot is cut for chain adjustment on one side (Though two are better) fixed to the other end of the chain is a webbing to support the hull between the keel and rudder.

There are 3 beams in the base frame, one each side and one for keel support with removable and adjustable side plates that slide in or out, this beam runs between both sides, with another beam at each end you have a box with arms.

Small truck wheels and tyres are cheap and plentiful.
If you would like a steering jinker a simple pivot on another beam and two front wheel assemblies complete with steering arms can be bolted to a plate and it bolted to the jinker frame, a steering rod fixed between the tow beam and steering arms on each wheel assembly will be a simple task.

Rear wheels can be mounted as above, though there are a few variations on this.

Hope this helps......:)

One last tip:
Contact you local scrap yard, they have the steel, wheels and most have a welder on their payroll.

I build both with the help of the "offsider" in a local scrap metal yard.
 
I had two built, the first for a Sigma 33 was on Transit front axles and wheels but the second for a 38 was on proper large lorry wheels and ran better even with the heavier load. I will search my CAD archive for the drawings or I may have photos. Basically you get two front axles complete with steering arms and wheels, take the brakes out as they will soon sieze; the platform is two steel beams about 3-4m. long welded and bolted about 1m. apart with platform made from a ladder of 150x75mm. inverted channel sections. The arms are made from similar channels and are cranked at about waterline level. The arms are adjusted by 4 agricultural bottle screws which are extended to about 1.2m. long by cutting in two and welding the two ends inside steel tube. I had two drawbars one short one for moving about unloaded (I used to tow it home at dead of night for painting) and a long one for the tractor. There were several copies made for members of the same club. It is possible to have the rear axle fixed or steerable which helps if the yard space is very tight. In winter we took the weight off the tyresby putting blocks under the extended channels which carried the arms. I f you are going to keep it for a while prime and paint it well at the start. Use any gloss you have over a good primer but plenty of coats.
If you make it heavy enough and paint it well you will get about £2k+ for it if you ever sell it, there is always a demand for a good one.
 
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Underdog
I just noticed wher you are, there used to be a guy in Islandmagee, Fred Adrain, who specialized in making yard trolleys to a very high standard. Don't know if he still does it but you will see plentyof examples of his work and find out about him if you visit the boatyards at East Antrim or Carrickfergus sailing clubs.
 
Here's a photo of my trailer that will give you an idea of what is involved. Mine is built on Transit axles but for your size boat I'd go for lorry axles. You can just about see how the steering is organised (both ends). The vertical arms reach about 2 ft above deck level but they only need to be that high if you are going to float into it. Most of our club trailers fit Acro's once the boat is ashore to keep it more rigid. Some use 'U' channel for the keel to sit in.
 
Additional thoughts

Depending on your boat keel design many people have had to remove their keel to replace sealant around the joint. You might find it useful to design the trailer from the beginning with ability to support the hull and to be able to remove the keel support so drop the keel down. Have like a large rectangle of angle steel around under the keel with 4 cross members to support the keel. Have the cross members bolted in so they can be removed one at a time for painting under the keel or all for keel dropping.
Think also about the amount of time you will spend scraping and painting the hull. A floor will make the work surface level but that may be too high for easy work on lower hull. So removable floor could be a help. Even so you will find yourself lying down for some parts of the hull and on a ladder for others.
Ask other people about their experiences and preferences. olewill
 
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