Hobie Bob installation

We were flying last weekend but when I tried to go solo, I kept capsizing. So, I am getting ready to install the hobie Bob on a H18. The instructions seem quite clear except for the cap on the long rivet (which rivets the mounting shaft directly to the mast). I cannot understand how the cap is being used. Do you put the cap on the rivet and then insert it through the shaft and mast and pull on the nail, or do you insert the cap in the mast, the rivet in the shaft and then install ? what is the reason for the cap?

Also, since there are different kinds of alluminum, and some of the rivets (and certainly the eye straps) are stainless steel....what about galvanic problems? should thre rivets and the eye straps be separated from the mast by way of plastic film, silicone, something?
Thanks to all for your kind help
Roberto
Daytona Beach (ouch, it's cold today)

You won't regret installing the Hobie Bob. Way better than the 1 gallon milk jug I used to use.

Assuming you are using genuine Hobie parts, the rivet cap is designed to 'seal' the hole and make it watertight. The rivets are made out of monel, and any galvanic action can be ignored as immaterial. If its from Hobie, its good.

Make sure your rivet gun is a good one, preferably air powered. Monel is tough, not soft like aluminium, which means it requires considerable power for the 'nail' to be pulled up and properly seat the rivet.

Locate the Hobie Bob shaft in place on the mast, secure it, place the straps where required, drill the holes (using the straps as templates,) slide the rivet cap over the (bottom) end of the rivet, slide the rivet into the hole of the strap and then into the mast, have your helper push down on the strap so that it is very snug to the mast, and fire up your rivet gun.
That's it. Once the mast is down, about 8 minutes work.

To avoid capsizes, try turning out of the wind, (not into the wind, lots of posts on this one,) especially when beating, then releasing the mainsheet. When running downwind, try releasing both the traveler and the mainsheet. Teabagging is preferable to capsizing. Enjoy.

_________________
2015 H16, with spin,
SOLD 1989 Hobie SX18 Sail # 1947 "In Theory..."
'Only two things are infinite, the universe, and human stupidity. But I'm not sure about the former.'

John,
Thankyou for your help. I should have all original parts. There is only one cap, not three. The cap is intended for just the one extralong rivet (the one that goes trough the shaft, not through the straps). However if I dress the rivet withs its cap, the factory predrilled hole in the shaft is too small. The predrilled hole on the shaft is 3/16 which is the right size if the rivet had no cap. With the cap, I would guess the size is about 15/64. That is why I'm thinking that, maybe, the cap should go only through the mast and not through the shaft and mast. Also, the cap is about 2/3 the length of the rivet, so, if you dress the rivet before placing it in the hole, the cap will be fully seated, but the rivet will be sticking out by 1/3 of its length. To further comlicate things, I only have one cap. If caps are necessary to seal the mast, the lower strap would also need two caps, which did not come with the rest of the stuff. The lower strap is to be installed in an area that will definitely need sealing, the higher strap is ok because it'is above the watertight section. I know it's a simple job, but I want to have it clear in my mind before I flip the boat, and start improvising
Thank you
Roberto

Ummmm, you are right, the mast has to be sealed.
That's what those rivet caps are for.
I forget, do you have a one-piece mast or a comp tip?

As I recall, we did this job about three years ago on my one-piece, and likely I am getting older and more forgetful.

So dress the rivet under the strap?
eMail Matt Miller?
Call your dealer?

_________________
2015 H16, with spin,
SOLD 1989 Hobie SX18 Sail # 1947 "In Theory..."
'Only two things are infinite, the universe, and human stupidity. But I'm not sure about the former.'