Roberta's Torpedo

[slug]

I would use square head set bolts (they are hardened) with wire holes thru the head to lock them from vibrating loose...or out!
There is a proper procedure for wiring also.....I'm certain you can figure that one out.
Several years ago we were in the Abacos on our sailboat and helped a couple on their NEW famous make power boat repair their drive. Factory had not used locks or drilled set screws to seat in to the shaft !!! I had spares and we used a piece of shim stock from a beer can to tighten up the coupling. It got them home to Maine.
Doug

[Roberta]

Thanks, Slug!

I found a prop shaft repair facility in Wisconsin about 90 miles from me. I plan on calling them tomorrow and have them mate my prop shaft to either the straight hub I have or possibly machine the shaft I have and have a tapered hub fitted to it. I ordered the shaft a bit longer than needed, so they should have the stock necessary to do the machining. I had originally planned to use a tapered shaft hub, if I had the room. I ordered the straight hub to use on a tube to get a preliminary fit. I may still use it, but want to talk to the repair people first to see my options and cost. This is a very important area and I want to get it right.

Roberta

[slug]

I know I'll ruffle some feathers here, but I prefer the straight hub for ease of removal if required, and security. I think the tapered hub is overated (IMHO)
Doug.

[billy c]

I prefer the straight hub for ease of removal if required, and security. I think the tapered hub is overated

agree

[Roberta]

I know there are trade offs to both methods. I do already have the Buck Algonquin coupler and it does seem very well made and sturdy. I do need to get the shaft shortened a bit and right now the fit is too tight to get the coupler on the shaft. So having a pro fit the hub,that is knowledgeable in how these things go together, will be very enlightening for me. They will also be able to lap the prop and fine tune it as well. This will make for as good a setup as can be.

I have the Globe Drive Saver in place and the engine aligned. Once the coupler, shaft, and prop are all properly mated, I'll be able to get them all in perfect alignment.

I set the boat on the dollies straddling the frames around the motor so as to minimize any deflection and try to simulate conditions of a floating boat. I hope this will eliminate, or at least minimize any change in alignment. The hull is extremely solid and I hope there are no issues. Wow!!! Outboards are sooo much simpler.

Roberta

[Joris]

Roberta,

I think is't a good idea to have a pro put it all together. Luckily i've never had one fail in a boat but as an ex-R&D test-engineer in a transmissions lab i've seen many couplings fail under load. And ,without going into much details, when you push 300+ hp through a 1" shaft that runs under you seat, you better make sure everything is put together as it should.
Buck A. couplings are almost always undersized and should be reamed to fit, then faced. Modifications to the design ; drilling holes, changing measurements to key or similar should be avoided. If the machineshop agrees with such modifications, turn around and run.

Nice work on that beauty btw.
Joris

[slug]

Roberta; You'll be doing exhaust soon, and I've found that Summit Racing stocks some 3 and 4" bends in stainless if you plan on welding up your own. Tubing is cheaper from a metal supply source tho'.
Doug

[Roberta]

Thanks, Joris!!! This will be my plan. Have the coupler properly joined to the shaft at the correct length, get the runout checked and corrected, get the flange of the coupler faced, get the prop lapped to the shaft, all keys properly fit, and get the prop fine tuned.

Hey Doug!! I found some really nice polished 4" 316 elbows and had beads welded on the ends. The tubing is 0.086" thick and they look really nice. I will be using Shields Blue 350 deg. F. hose to join everything. I have some 4" fiberglass exhaust tube and two ski mufflers from Centek. I'll probably start assembling all this this week.

Roberta

[Rich Coey]

MUFFLERS?, MUFFLERS?, WHAT?

[Roberta]

Just enough to tone down the harshness. With just two baffles in the upper half and a peak straight through, I doubt that will kill off the throaty growl of that Crusader motor.

Roberta

[Roberta]

Well, today was a sort of a bust on working on the Torpedo. I did get sole boards cut last week and over the weekend gave the bottoms of the boards two coats of resin. But today was laundry day and I also took the prop shaft, prop, and coupler up to Two Rivers, WI to be properly mated. That was a 5 hour round trip. The company that I am dealing with will be cutting the shaft to the proper length, lengthening the keyway, machining the coupler to fit the shaft, boring holes for the set screws, checking shaft and coupler runout as well as facing the coupler. They are also using a Hale MRI to check the prop to see if it needs any tweeking to get it perfect and will be lapping the prop onto the shaft. I should be able to pick it up later this week and get it all installed on the boat over the weekend. It was really nice to find a place reasonably close that will be able to get everything together properly. Gives me a warm fuzzy.

The rest of the week I will be running wiring harnesses and hoses, coating sole boards, cutting holes in the dash, and getting some more done on the sole. I'm holding off on the exhaust until I get the prop shaft in. I don't want to crawl over it if I don't have to. Might get some done.

Roberta

[Bill Edmundson]

Roberta

And! you thought the turn was fun!

Bill

[jenko]

As we are talking lapping prop to shaft I thought this might be of interest http://www.pbase.com/mainecruising/fitting_a_prop

[mrintense]

Please forgive my ignorance, but is this prop lapping process something that needs to be done with outboards as well?

[Roberta]

Well, the flip was fun since all I had to do was worry and fret and run around with the camera.

Good article about lapping! Thanks for sharing!!! I will save it for when I need to replace the prop.

Most outboard props that I'm familiar with are on a splined shaft and do not get lapped. Tapered shaft fitups need to be lapped to reduce slight differences in the contouring of the tapers between the prop and the shaft. Pretty much talking differences of less than 0.0001".

Roberta