I know there are rubber alternatives, but looking on Transair they seem a little more expensive (not sure if they're cheaper elsewhere, but I'm not specifically looking at that). I 'think' your cradle will be alright, if used in conjunction with wooden props. You can always strap the hull to the cradle as well to stiffen it up a bit, but not essential. If this is not possible (for example, if it would overload an axle), you must use an additional method of securing. You could:

Frictional lashing is most effective when the angle of the lashing relative to the load bed is as close to vertical as possible. If the angle is less than 30°, the lashing will not be effective. The example shown was made about 30 years ago of Honduras mahogany. For reasons of maintenance, oiled teak is preferable. Varnished wood simply wasn’t made for cradling heavy chunks of metal. Provided you have time inthe lift dropping the rudder out is fine. Providied the cradle is big enough to provide support as you take strain off the slings then you will be best putting the boat into this first so that she is fully settled with the weight on the keel before putting props in all round. There is a real risk of dammage if you put a prop in before all the load is off the hoist of the prop causing excessive pressurein a single spot. As said elsewhere you may well find that the boat pivots as the weight comes off. You will also need to ensure that the boat stays upright. If you havn't done this before please get somebody who has done a few to help. Once settled in the cradle a good number of props tied together as shown on the Saddler should be fine. Make sure that the props are positioned on strong areas of the hull. If you are determined to leave the mast up strip off all you can, frap rigging hard to prevent vibration and even consider wrapping a warm round and round the mast as a 'vortex shredder'. I personnally thing the right size cradle is the thing to get and take away a lot of trouble and worry. You must secure any divisible load that is higher than the headboard. You can use additional lashings to stop the load moving forward when the vehicle brakes. Indivisible loads You can achieve positive fit with cylindrical loads (such as paper reels) when the extremity of either one reel or two reels side by side is within 8cm of the side of the vehicle or trailer.When securing a load in the middle of the load bed, or a load that is not very tall, you should either:

Cut out the wood; then lay the an-chor on the two pieces and, lining up on the centerline, mark the positions of the crown, fluke, and shank recesses.direct - where one end of the lashing is attached to the load and the other end is attached to the vehicle or trailer The same holds true if you need to apply de-icers or other treatments such as washer fluid or anti-freeze when temperatures drop below freezing. Make sure you use enough lashings to prevent load movement under normal driving conditions. If there is a serious load shift, enforcement agencies will refer to BS EN 12195 1: 2010 Load restraining on road vehicles Safety Part 1: Calculation of securing forces when deciding if you have used enough lashings.

Most ratchet straps used in the UK have a label attached to them with information about their strength and how they can be used. Design the larger piece so that about 3″ of the flukes and all of the shank are contained in a resting posi-tion. Design the crown rest with at least an inch of width outside either edge of the crown. Now you’re ready to chisel out the !recesses. If you’re an experienced ‘wood butcher, you’ll have your own procedures. If not, here are some suggestions: Gather the necessary supplies: two pieces of 2×4 lumber, metal corner braces, and screws. You’ll also need a saw, drill, wrench, and screwdriver.

Draw a centerline on the piece of wood and transfer the whole shape by stationing your cutout or template on the centerline. Then draw around the template, and flip the template over to get the other, exactly match-ing side. The friction between most loads and the standard load beds of most vehicles and trailers is generally low. The weight of a load alone cannot be relied on to keep it in place once the vehicle is moving, even if the load is very heavy and cannot be moved by hand when the vehicle is stationary. Step 1: Cut the pieces of lumber to the desired length – generally around 4-6 inches long. Both pieces should be cut to the same size. inspect any straps involved in a load shift incident - do not use them if they’re worn or damaged, even if the damage appears to be minor