I used Ford 'Transit front axles for both sets of wheels - although, now I wish 1'd used lorry wheels because of their greater carrying capacity. The axles were cut in half - not rec¬ommended unless you know what you're doing - to widen the track enough so that the keels wouldn't foul them. I welded carefully jigged angle iron to support the cut ends of the axles, which were then bolted, via spacers to the cross members and side beams.

Steering and draw bar
A lot of attention was given to the steering as I didn't want the trailer to wander around behind the towing vehicle. The 11ft long drawbar also had to be easily removable for storage - all of which increased the complexity of the steering.
The various linkages and pivots were made with minimal amounts of play, and were also strong enough to limit any flexure. An extra 'pin' hole was added to the steering arm, which enabled the front steering to be 'locked' straight. The trailer could then be pushed from the front.
As the rear wheels also steer, with the aid of a long bar, reversing is a doddle.
Goal posts
These don't really help the boat to locate on the trailer, but they're useful to hang on to or push-off if the manoeuvre goes 'pear-shaped'. Their real purpose is to show where the trailer is when submerged. I painted green 'gauge marks' to the front posts to show how much water there is over the trailer.
All the posts are removable - oth¬erwise the trailer would be far too wide to travel on the road - and I fitted some wooden timbers between the chassis members, on which the goal posts could be stowed when not needed.
Keeping rust at bay
As saltwater is so corrosive, it's important to protect your wheel bearings - and any other moving parts, such as the steering joints ¬from corrosion and eventual seizure. To protect the wheels I silver soldered grease nipples into the bearing caps. Providing you give them a few 'pumps' of heavy grease with a grease gun before and after water immersion, any salt water that does enter is forced out again. Experience has taught me that heavy grease, such as Keenol, gives the bearings the best protec¬tion. I also coat all the removable pins, 'R' clips, nuts and bolts with thick gearbox oil. This is a messy job but it's a small price to pay to keep them running free.
Was it worth it?
This trailer is fairly sophisticated and it does everything I wanted.
The only trouble I've had over the last 5 years is with the front steer¬ing, which used to bend the small steering pin. The pictures show the current design, which now works fine. It took me a little over two months to design and make the trailer, which I consider a worth¬while investment in both time and money - saving me hundreds of pounds in launch fees alone. It also means independence, so I can choose times convenient to me instead of waiting for the boatyard
to fit me into their busy schedule.