Cherubini H36 Definitely Faster Than 10 Days Ago

[rardiH36]

Just re-launched my 1980 Cherubini H36 after about a week on the hard for a bottom sanding/repaint, changing to a lower resistance Campbell Sailer prop, and removing the plastic flaps that covered the skeg to rudder joint. These flaps, originally designed to flex tight against the rudder to reduce turbulence at the skeg/rudder interface, had become stiff and permenantly pointed outward at about 30-40 degrees. In various boatyards, I never saw other boats with this feature, so I figured that even when these flaps were new when they were pressed flat against the rudder, the positive effect must have been minimal.

Anyway, my boat is definitely faster than it was. Not that the knot meter was ever accurate (tends reads fast vs the gps -- but this can be hard to judge because the strong SF Bay currents affect the gps reading as well). But in the couple of years prior to the haul out, the fastest the I ever saw (and just for brief moments) was a bit over 8kts. Yesterday in ~15 kts winds with my 135 Genoa almost fully deployed from the fuller, the meter exceeded 9 kts several times with the angle of attack somewhere between a close reach and beam reach. And I was frequently in the mid 8kt range at various points of sail.

A lot of fun. Maybe I'll no longer feel that I'm one of the slowest 34-38' boats on the bay! We'll see the next time I'm out on a Saturday and Sunday.

 

[Johnb]

On the way home from our haul out at Svendsens for a bottom job and fitting a Flex-O-Fold propeller we sailed back to Emeryville in the lee of Angel Island, against the tide and whereas previously I would have expected to need help from the iron wind to get through there, we sailed. I was amazed at the difference in performance from a clean bottom and a folding prop. It is even more marked on light air days. I pay a diver $100 every 3 months to keep the bottom clean because I love the way she sails.

 

[rardiH36]

Hi JohnB:

I just typed out a message to you using the forum's send eMail function since the topic is our respective boats. But something locked up somewhere and its been lost. Nothing important so not really necessary to type it again.

Anyway, I'll keep an eye out for the Cherubini H37 profile and hope to cross paths with your Kinyonga someday.


regards,
Richard

 

[Johnb]

O.K. we get down to the boat every weekend we are in town and are planning to be out on opening day.

 

[sail_4_me]

When you removed those flaps did you have to seal the holes and fair it?

I have tin flaps. Last summer a bottom section cracked/bent and left a good scrape on the rudder where it touched. I also have a maxi-prop, so I think its time to remove them. I looked inside under the my rudder post and saw a lot of large bolts in that area, so I assumed it would be a big job.

 

[Ed Schenck]

If your flaps are bolted that would be a previous owner modification. The tin flaps are original and they were screwed into relatively thin fiberglas. That is a narrow void, impossible to get into. Cannot imagine what bolts you are seeing.

I carved some wood and glassed it in down there. Then the screws went into something solid. I have since removed mine also. Best way is to use a lot of a good epoxy mix and fair that recess. I wish I had. But I know that my screw holes do not go through into that void. Yours will.

 

[rardiH36]

Hi Ed:

Not sure about bolts and tin you are referencing. Not a feature on my boat. Difference between the 36 and 37?

Anyway, my flaps were like the one in your picture, only they were composed of 1/8" nylon type sheet plastic similar to the plastic that tupper-ware is made from. They were attached to the end of the hull skeg with abut 3/4 -1" screws just like in your picture. I didn't count, but 5-6 screws. The very aft end of the skeg on my H36 where the screws penetrated was at least 1 1/2" thick solid fiberglass. Somehow the lower corner had a fairly large chip section through the gelcoat and into the FRP. There was no hint of a void in there. After removing the flared-out flaps (and scraping off a few mussels that had grown behind them because it was not possible to reach there when hull cleaning), I reamed out the screw holes, rinsed them with acetone, packed them with marine grade epoxy, sanded the area to rough it all up, and finally painted with the modified epoxy bottom paint. I didn't bother to fill the recess that the flaps resided in.

Good riddance flaps!

 

[sail_4_me]

In the picture you can see screws (sorry, not bolts ) poking out through
the fibreglass.

I have tin strips screwed in, so I now doubt these are the same ones.

I'll find out Saturday in any case . Epoxy and fairing sounds like the way to go.

 

[Ed Schenck]

Never new that the H36 also had the flaps Rardi. Wonder why yours went into solid glass and they did not do that for the H37C? As you can see from "sails-" picture it really is hollow down there. And shaping something to fit and glass in down there was quite a project. I like knowing its solid now.

 

[rardiH36]

Aft'est Most Inside Point of a Cherubini H36

Sail-4-me's photo from his Cherubini H37, got me curious what the aft most interior point of my Cherubini H36 looked like and if it should be an item of concern as it has been for Ed's Ladylove.

Squeezing myself under the pedestal area (where I have been many times), I found that it was impossible to even see the area. Reaching through a gap with a digital camera was the only solution. The attached picture is facing aft. No screws poking through from the outside. Actually, the holes for screws that held the flaps in place (from the outside) are further aft than the hull side to end cap joints in the picture. Seeing this picture and remembering the configuration on the outside from when the boat was hauled, I would say the fiberglass layup at the end of the skeg where it meets the rudder is solid and at least a couple of inches thick. Seems to be no worries construction.

 

[Ed Schenck]

Very interesting difference, H36 to H37C. So that would be the rudder tube and bottom of the stuffing box? Then your flaps screw in behind that, almost certainly solid fiberglas. You should get that old nylon wire tie out of there.