20 replies to this topic

[Gouvernail]

We have issues with attaching things.






Specifically:

1. The mainsheet block on the inside of the hull .
builder diagrams show the back edge of the reinforcing block 780 mm from the transome. +- 10 and we sanded it a bit so the back edge is just in front of 780

The rear mainsheet block is supposed to be 786 +- 5 from the transome.



We elected to put the attachment point a tad foreward of the spec so we would not be at the edge of the block. Is this gonna screw up our measuring day??


2. We got some little rubber chunks to serve as spacers in the centerboard trunk.



How do people put these in so they won't just fall out?? Are the little pieces of what seems to be rubrail really the best way to do this or should we get some Delrin machined by a willing fellow grandpa??

Attached Files

•  from side.jpg   382.22K   88 downloads
•  from behind.jpg   303.15K   108 downloads
•  mainsheetmounts.jpg   532.22K   115 downloads
•  trunkplugs.jpg   354.85K   93 downloads

[ortegakid]

UHMW is what i've used on all my boats for cb slot, cheap and easy to machine, can be had very reasonably from Mcmaster-Carr.

[Gouvernail]

UHMW is what i've used on all my boats for cb slot, cheap and easy to machine, can be had very reasonably from Mcmaster-Carr.

how do you fasten it in place??

[Steve Clark]

Those numbers are kind of add aren't they. You really cant make it look right using nominal. I would push the main sheet mounting block toward the back end of the tolerance and mount the eyes trap a wee bit forward of nominal. Should have enough room to make the eye staps look more centered on the block.

If the measurer takes you down for that, he is being a dick and welcoming you to he true spirit of the Optimist class. Don't you know you are supposed to BUY the stuff the coaches tell you to buy? What is the Grandpa built a boat crap?
Completely out of touch with the spirit of the class.
Will probably scar the kid for life.

We used to glue little foam bumpers in with a blob of silicone. Ours were made out of neoprene, so they glued pretty well. I suppose "Fuck the Next Guy" aka 5200 would work better, but we didn't want to have two sealants on the floor. I would avoid Delrin because it is too hard for the leading and trailing edge of the board. You can just put a blob of silicone there like the Europe dinghies did. That works just as well.

SHC

[notallthere]

What about adhesive backed velcro?

[scowlover]

As mentioned before, the measurer would be a dick if he tagged you on the mainsheet block. Those rubber pieces are standard. We normally superglue them in and it works really well. It can also be removed with a little force if needed.

[Touch of Gray]

Its been a while but I think you can't add anything to the CB trunk like a spacer or??. Check class rules. Yes that makes the CB "floppy" but applies to all.

Pretty little monster garage job.

TOG

[ojfd]

Pretty little monster garage job.

+1

I'd love to know how this one goes against the mass produced GRP ones.

[GD206]

We have issues with attaching things.


Ihave been the measure chair for the opti nationals they do not measure the location of th blocks in the boat.



Specifically:

1. The mainsheet block on the inside of the hull .
builder diagrams show the back edge of the reinforcing block 780 mm from the transome. +- 10 and we sanded it a bit so the back edge is just in front of 780

The rear mainsheet block is supposed to be 786 +- 5 from the transome.



We elected to put the attachment point a tad foreward of the spec so we would not be at the edge of the block. Is this gonna screw up our measuring day??


2. We got some little rubber chunks to serve as spacers in the centerboard trunk.



How do people put these in so they won't just fall out?? Are the little pieces of what seems to be rubrail really the best way to do this or should we get some Delrin machined by a willing fellow grandpa??

[bruno]

Delrin use
Gflex

[P2 Marine]

1) Put the blocks where the rules say or it will be a cheater boat for no reason and the measurer will flag it. Opti measurers are thorough and tough.

2) I bedded those little blade protectors in with 5200 and it worked fine.

Cheers,
Rob

[Sharkie]

As mentioned before, the measurer would be a dick if he tagged you on the mainsheet block. Those rubber pieces are standard. We normally superglue them in and it works really well. It can also be removed with a little force if needed.

In my (granted limited) experience as a volunteer at an opti national regatta, it's generally not the measurer who is a dick, it's the opti parents / coaches who are the guilty ones.

[Gouvernail]

The block thing should be really simple.



Tolerances are there for building variation and incompetence. We didn't push any tolerances becasue we don't know which way is faster on any given tolerance anyway.



With the block's back end at 780 which is the center of the builder's 10 mm plus minus tolerance, there is only 6 mm of space behind a perfectly installed block.

The edges of the eye strap would extend beyond the block and make a hazard for catching things.


Nobody intended to have the boat be built such that the mainsheet bolock would attach improperly to the "just for that purpose" reinforcement block.





On a boat whose reinforcement block was installed at the front of the tolerance (790) A well centered aft mainsheet block (786) would miss the reinforcement block entirely.



Nobody intended for such a situation to be possible.



I measured a bunch of 1980s Optis at our club and 100% flunked the new mainsheet measurement.



I gotta believe the measurement was changed but nobody noticed to change the wood builder's directions.



I have been an official measurer in various clases since the late 1960s. Measurer's are there to protect the rules and also comprehend the intent of the rules. ( let's get everybody out there in boats whose performance is not enhanced by sneaking around the rules.)



For that reason, I must believe any human measurer will understand the mainsheeet bl;ock location on a properly built wood boat ( reinforcement at center of tolerances) will just have to be another five mm in front of the location specified in the new rules.



That measurer would grant an exception for the boat built according to the Opti Class builder directions and contact the class with instructions to fix those same builders directions so this problem will not repeat itself.





If whoever measures our boat disagrees with my assessment of the situation, I will grind out the reinforcing block, Install the reinforcing block at the aft most extreme of the tolerance, install the mainsheet block, and send lots of photos and documents to teh class suggesting somebody fix this mess. .


I sure hope it never comes to that.






Meanwhile....Meanwhile...


anybody know how to install the wind vane?? we have a hawk brand vane with two black plastic tubes that seem destined for two predrilled holes in the mast section.
But the metal rod just slides up and down in those black tubes.and I have no idea why everything won't just fall out.

[nzrat]

we built all the good boats In New Zealand that the GRP ones could not compete with in the 90s and are about to replicate the process again with my Farther for my son. we have the Laurie Davidson offsets developed for a syndicate my own interpretaion and my Farthers interpreationall these boats have been at the top of their game when they were launched this boat will be quicker than a grp boat as you can build a straighter boat a round bottom hull (curvature through the section )and if the measures chuck you out for anything check the measurement, dispute what they say and get it remeasured a lot of the measures have a hidden agenda that lends to the mass produced GRP boats this is contrary to the orginal spirit of the class

[Luke Piewalker]

Off the top of my head do the plastic inserts for the hawk poke all the way through and have the sail ties holding them in?
i've seen it once but can't remember the fine detail.

[European Bloke]

The top two sail ties (one normal horizontal and one at an angle to stop the sail popping off the top of the mast) tie through the black plastic tubes. Pushing the tubes into the holes in the front of the mast tensions the ties more than you easily can just tying knots. Then you put the windex inside the mast tube. through the holes in the plastic tubes, to stop the tubes coming out of the holes.

Back in the day I sailed optis (winner Mk5 Mk6 days) a couple of my mates had wooden boats built by their Dads, who were very talented at that kind of thing. One won the UK champs and went to the worlds in his and the other was top UK girl and went to the Europeans in hers. I don’t know how much has changes since the Mk6.

[Gouvernail]

The top two sail ties (one normal horizontal and one at an angle to stop the sail popping off the top of the mast) tie through the black plastic tubes. Pushing the tubes into the holes in the front of the mast tensions the ties more than you easily can just tying knots. Then you put the windex inside the mast tube. through the holes in the plastic tubes, to stop the tubes coming out of the holes.

Back in the day I sailed optis (winner Mk5 Mk6 days) a couple of my mates had wooden boats built by their Dads, who were very talented at that kind of thing. One won the UK champs and went to the worlds in his and the other was top UK girl and went to the Europeans in hers. I don't know how much has changes since the Mk6.

INSIDE teh mast...Well DUH!! So brilliant yet so not obvious at first. With the extra stick inside there will be less windage!!!



Thanks

[BuggarTheBone]

Gouv,
Do away with the two plastic tubes. When you do the horizontal and diagonal loop ties at the top of the mast just loop them in and back out the same hole in the mast. Then, simply pass the rod for the windex through the loops you created INSIDE the mast. You can't tension the loops until you put the rod down to act as backing rods for the two loops.
You can use the plastic, but it wears out and breaks eventually. Best line for this is some 2mm spectra.
Shocking setup really, but at least they are all the same.
Cheers
BTB

[Gouvernail]

Gouv,
Do away with the two plastic tubes. When you do the horizontal and diagonal loop ties at the top of the mast just loop them in and back out the same hole in the mast. Then, simply pass the rod for the windex through the loops you created INSIDE the mast. You can't tension the loops until you put the rod down to act as backing rods for the two loops.
You can use the plastic, but it wears out and breaks eventually. Best line for this is some 2mm spectra.
Shocking setup really, but at least they are all the same.
Cheers
BTB

OOOOh I LIIke that!!!

[optiguytom]

BuggartheBone is correct! You don't need those so-called "top pins" or "top plugs". They are superfluous. The sail ties are easier to adjust without them. The upper tie should be parallel to the top of the mast holding the sail against to a few mm away depending on the sail and wind conditions (Basically against the mast is 95% correct). The diagonal is used to keep the sail within measurement limits. It adjusts the position of the sail band between, and NOT touching (touching is not legal), the mast bands. Stupid rule....why not just get rid of the bands altogether??

Wooden Optis RULE!

[whispers]

As mentioned before, the measurer would be a dick if he tagged you on the mainsheet block. Those rubber pieces are standard. We normally superglue them in and it works really well. It can also be removed with a little force if needed.

In my (granted limited) experience as a volunteer at an opti national regatta, it's generally not the measurer who is a dick, it's the opti parents / coaches who are the guilty ones.

+100