A proto-type mast roller crutch was built a few months ago.
It's made of recycled timber and has a 4 inch blue keel roller (blue is for aluminium, it's a harder-longer wearing compound than other roller colors). It's bolted to the aft rail and through the transom.
It is an A-frame design which straddles the tiller cutout. The tiller and rudder can be shipped and used to steer, while the mast is lowered, sitting on the frame roller crutch. It should make for easy motoring/manoevering at the ramp/dock while the mast is in it's lowered position.
The roller height is the same as before, so the mast is 2.2m above ground level (to fit under standard 2.4m clearance shed doors or carports)
Mast roller crutch |
I have to raise/lower mast after getting past the port bridge. The roller should make rigging/mast raise and lower much easier and faster than before in the "mast raise anchorage" seaward of the bridge. The bare wooden construction of the frame has the ye olde pirate vibe too. ("one day" the stainless version of the roller A frame may be fabricated?)
I guess future sail boats in Ross River may have to harken back to the "golden age" of sail (such as in the already overbridged ports of Europe, UK and Europe) Built with lower and lowerable rigs, such as two masted gaff riggers, with decent mast tabernacles and mast lowering bow frames. There are some modern classic designers around but these boats tend to be rarer and more expensive than the average 1970s glass TS.
In the photo above, i have a new tarpaulin to cover Teria for the upcoming wet season. The tops of the mast crutch needed to be sawn off so the tarp would hang well, good thing it's a wooden prototype still in its design itteration phase.
Silky oak wood posts bolt through transom. |
Mast roller, crutch jaws trimmed back for tarpaulin. |
Hardwood rail clamps with stainless bolts. Treated pine fence paling for top cross brace. |
The concept of the mast roller crutch has been around for awhile and is sometimes seen on a small number of other trailer sailers. I couldn't find a design to suit my boats setup, so designed my own. It was just old school sketch pad, then build it and trim to fit. No computers were involved (or harmed :-) ) at the design stage.
It's not apparent but the trickiest part was matching the wood posts bases to the reverse transom angle. Some strange angle cuts were needed here. It's one of the reasons to use wood for the Mk1 frame.
If this design proves it's self then it would be easier to fabricate one in stronger sleeker stainless steel one to similar dimensions.
Other possible ideas, with this as a base frame..
1) Solar panel mounting
2) Extension crutch (to get standing headroom in cockpit, with a slatted "boom awning" over it)
3) VHF radio antenna mount..(higher off water, more range)
4) White LED stern light mount (higher, longer visibility range)??
Original mast crutch |
Above is the previous mast crutch for road trailering, it was attached to the lower rudder pintle and aft safety rail with two guy ropes to the sides to stop swinging about. The mast extended further aft, about 3 feet past the transom. This lengthened the total trailing length and was a bit fiddly/time consuming to set up and remove each time at boat ramp.
An additional benefit of the new roller crutch is the mast can sit further forwards, in-line with the outboard bracket board. So the total boat on trailer length is reduced by a couple of feet, making it better for backing up and fitting into carports or sheds.
Mast sits further forward on crutch |
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