Wednesday, December 16, 2009

Re: [Electric Boats] MARS motor shaft to spline coupling?

 

A few minutes at McMasterCarr.com will probably come up with a cheaper off the shelf solution. The spline part will be hardest. Do you have access to a marine salvage yard that may have broken parts?


-----Original Message-----
From: Myles Twete <matwete@comcast.net>
To: electricboats@yahoogroups.com
Sent: Wed, Dec 16, 2009 3:00 pm
Subject: RE: [Electric Boats] MARS motor shaft to spline coupling?

 
Options that I know of:
·         Cheapest (~$50):
o   Buy a 7/8" keyed shaft coupler
o   Buy or make a short tube that slips over the OD of the coupler
o   Weld or JBWeld the tube to the coupler
o   Make a a 1 1/8" spline fitting out of the inside part of the tube by "casting" a spline using JBWeld or titanium putty or other strong epoxy
§  Fill the spline part with wax
§  Lube your spline with WD40 or other lube to act as mold release
§  Mix appropriate amount of epoxy and pour into tube end
§  Smoosh the spline into the epoxy, keeping the spline shaft and the coupler coaxial (biggest problem)
§  After cured, use gear puller to remove the new coupler from the spline
§  Voila…coupler made for under $50
·         Cheap (~200):
o   Buy a 7/8" keyed shaft coupler
o   Buy a 1 1/8" spline coupler (if available) or spline gear/pinion
o   Bore one end of the spline coupler out to the outer diameter of key shaft coupler
o   Connect, align and bond (JBWeld) or weld the 2 couplers together.
o   Cost: $200 or less I'd guess (mine cost $100 total---(1) 7/8" keyway coupler ($15), (1) used pinion gear w/14-pt spline ($35), plus $50 to grind one end of pinion down to 7/8" to fit in the end of the keyway coupler.
·         Expensive, but Best ($500+): Have a machinist make a coupler for you, boring for 7/8" w/keyway on one end and broaching 10-point spline at 1 1/8" on the other.
 
I used the first approach for my outboard motor (ETEK 7/8" keyway to 14-pt nom. ½" diameter spline coupler) conversion for about a year.  In my case, the splines were too narrow and would only last for perhaps 20-hours before self-disintegrating and having to be replaced.  After going thru about 3 coupler recasts, I made one out of titanium putty and used it until I discovered the 2nd method above.  That new coupler cost me $100 total and has now lasted 5 years or so---I used a lower unit pinion gear for the spline fitting and the pinion gear teeth on the OD were never ground off since they don't interfere in my use as a coupler.
 
-Myles Twete, Portland, Or.
"The REACH OF TIDE" electric barge cruiser: www.evalbum.com/492
 
 
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of David Goldsmith
Sent: Tuesday, December 15, 2009 8:40 PM
To: electricboats@yahoogroups.com
Subject: [Electric Boats] MARS motor shaft to spline coupling?
 
 
I've been working on getting my gear box ready to mate up to a MARS
brushless motor set-up. The gear box and flywheel housing will make
mounting the motor through a 1/4" al plate easy enough. The problem
I'm running into is how to mate up the motor to the gearbox input. The
MARS motor has a 7/8 keyed shaft. The gearbox has a 1 1/8" spline
shaft (10 splines.) I've done some searching and can't find a coupling
that will accommodate that spline shaft. Is this something I'll have
to have made custom or what? Any ideas out there?

Thanks,
David

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Posted by at No comments:

RE: [Electric Boats] MARS motor shaft to spline coupling?

 

Options that I know of:

·         Cheapest (~$50):

o   Buy a 7/8” keyed shaft coupler

o   Buy or make a short tube that slips over the OD of the coupler

o   Weld or JBWeld the tube to the coupler

o   Make a a 1 1/8” spline fitting out of the inside part of the tube by “casting” a spline using JBWeld or titanium putty or other strong epoxy

§  Fill the spline part with wax

§  Lube your spline with WD40 or other lube to act as mold release

§  Mix appropriate amount of epoxy and pour into tube end

§  Smoosh the spline into the epoxy, keeping the spline shaft and the coupler coaxial (biggest problem)

§  After cured, use gear puller to remove the new coupler from the spline

§  Voila…coupler made for under $50

·         Cheap (~200):

o   Buy a 7/8” keyed shaft coupler

o   Buy a 1 1/8” spline coupler (if available) or spline gear/pinion

o   Bore one end of the spline coupler out to the outer diameter of key shaft coupler

o   Connect, align and bond (JBWeld) or weld the 2 couplers together.

o   Cost: $200 or less I’d guess (mine cost $100 total---(1) 7/8” keyway coupler ($15), (1) used pinion gear w/14-pt spline ($35), plus $50 to grind one end of pinion down to 7/8” to fit in the end of the keyway coupler.

·         Expensive, but Best ($500+): Have a machinist make a coupler for you, boring for 7/8” w/keyway on one end and broaching 10-point spline at 1 1/8” on the other.

 

I used the first approach for my outboard motor (ETEK 7/8” keyway to 14-pt nom. ½” diameter spline coupler) conversion for about a year.  In my case, the splines were too narrow and would only last for perhaps 20-hours before self-disintegrating and having to be replaced.  After going thru about 3 coupler recasts, I made one out of titanium putty and used it until I discovered the 2nd method above.  That new coupler cost me $100 total and has now lasted 5 years or so---I used a lower unit pinion gear for the spline fitting and the pinion gear teeth on the OD were never ground off since they don’t interfere in my use as a coupler.

 

-Myles Twete, Portland, Or.

“The REACH OF TIDE” electric barge cruiser: www.evalbum.com/492

 

 

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of David Goldsmith
Sent: Tuesday, December 15, 2009 8:40 PM
To: electricboats@yahoogroups.com
Subject: [Electric Boats] MARS motor shaft to spline coupling?

 

 

I've been working on getting my gear box ready to mate up to a MARS
brushless motor set-up. The gear box and flywheel housing will make
mounting the motor through a 1/4" al plate easy enough. The problem
I'm running into is how to mate up the motor to the gearbox input. The
MARS motor has a 7/8 keyed shaft. The gearbox has a 1 1/8" spline
shaft (10 splines.) I've done some searching and can't find a coupling
that will accommodate that spline shaft. Is this something I'll have
to have made custom or what? Any ideas out there?

Thanks,
David

__._,_.___
.

__,_._,___
Posted by at No comments:

Tuesday, December 15, 2009

[Electric Boats] MARS motor shaft to spline coupling?

 

I've been working on getting my gear box ready to mate up to a MARS
brushless motor set-up. The gear box and flywheel housing will make
mounting the motor through a 1/4" al plate easy enough. The problem
I'm running into is how to mate up the motor to the gearbox input. The
MARS motor has a 7/8 keyed shaft. The gearbox has a 1 1/8" spline
shaft (10 splines.) I've done some searching and can't find a coupling
that will accommodate that spline shaft. Is this something I'll have
to have made custom or what? Any ideas out there?

Thanks,
David

__._,_.___
.

__,_._,___
Posted by at No comments:

[Electric Boats] Re: Pitch of Kipawa Propeller

 

I, too, wasted time with Kipawa last spring. If I can't get basic information about their product, I won't buy it.

My notes on the OMC props I have tried (or more accurately, consumed)
are

319774--7.5 x 7, three blade, cc, apparently nylon
318487--7.5 x 6, three blade, cc, apparently nylon
114848--7.5 x 6, three blade, cw, apparently nylon

You'll have to do work on these to make them fit a trolling motor. I have sometimes had to use bushings, or epoxy glue the center out of a stock prop, to make something that works. You may need a belt sander, a drill press and a dremel tool.

The three blade, nylon, aftermarket trolling (cruising) motor props
at BassPro appear to be pitched in the range of 4-4.5.

I'd like to try a 7.5 X 7 (or 8), cw nylon 3-blade prop if any of you stumble on the OMC number for one.

John Casperson

--- In electricboats@yahoogroups.com, Hans Kloepfer <hanskloepfer@...> wrote:
>
> I concur about your assessment of kipawa. For something so basic as prop pitch to be considered "proprietary information" is totally disappointing. I have a minnkota powered dinghy and would be interested in trying different props, but based on Kipawa's banal policy I won't be interested in experimenting with their products. This is a shame because from some reports the kipawa product seems a worthy alternative option for the minnkota motors, but you can count me out.
>
> Two enthusiastic thumbs down for kipawa inc.
>
> Hans K
>
>
>
> --- On Tue, 12/15/09, bosunj.rm <bosunj@...> wrote:
>
> From: bosunj.rm <bosunj@...>
> Subject: [Electric Boats] Re: Pitch of Kipawa Propeller
> To: electricboats@yahoogroups.com
> Date: Tuesday, December 15, 2009, 11:09 AM
>
>
>
>
>
>
>
>  
>
>
>
>
>
>
>
>
>
> Interesting that corporations have trained some so well that they don't automatically reject a company that won't give them the info they need to make an informed decision. Any company that acts like this doesn't deserve my money. Thank you for the heads up. I'll add them to the growing list of mostly Duhmerican't companies I won't do business with.
>
>
>
> --- In electricboats@ yahoogroups. com, "marka97203" <marka97203@ ...> wrote:
>
> >
>
> >
>
> > I've got a Kipawa 314 they sent for an E-30. It's 10" diameter. From
>
> > root to tip is 2.5 inches. The blades are not twisted very strongly.
>
> >
>
> > Does that make pitch the sum of the three blades, or 7.5?
>
> >
>
> >
>
> > For my own 650 pound all up 16 footer, the Kipawa prop did make a modest speed
>
> > improvement - but nothing like the 30% better range Denny Wolfe reports.
>
> > For that I had to add another battery.
>
> >
>
> > Mark
>
> >
>
> >
>
> >
>
> > On 12/14/09, gregory_west2001 <greg@> wrote:
>
> > > Does anyone
>
> > > know the pitch of the Kipawa props? If so, and assuming Kipara did not have
>
> > > you sign a nondisclosure agreement as a condition of the purchase, would you
>
> > > let me know the pitch? Thank you.
>
> > ;
>
> > >
>
> > > "If your just looking for speed our props on average show a 10 - 15%
>
> > > increase of speed over the standard Minn Kota Propeller."
>
> > >
>
> >
>

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.

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Posted by at No comments:

RE: [Electric Boats] APC Props = was kipawa

 

Great suggestion Denny-

 

Check out their list of props

http://www.apcprop.com/pindex.asp

 

For the price of a kipawa, you could by 10 or 12 of these in a variety of sizes and get the best match.  They even have SlowFlyer props (SF) which are designed for low rpm, higher thrust and have wider blades, and SlowFlyerPusher (SFP) that are designed to push (more efficient than using a tractor prop).  Even 3 and 4 bladed if you want to get adventurous (although they are quite a bit more).

 

Kevin

 

 

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of dennis wolfe
Sent: Monday, December 14, 2009 8:55 PM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Pitch of Kipawa Propeller

 

 

There is another better and much cheaper way if you do not need the weedless aspect of the Kipawa or OEM props. 

 

Use an APC model airplane prop.  They come in dozens of different sizes and cost about $3.00 each.  You can buy lots of sizes to try - with an ammeter and a gps you can measure the efficiency of each one.  I get mine from Tower Hobbies.

 

I got a 30% increase in range using a 10x6 prop on a MK Endura 36 driving a 14' canoe.  I got an even better increase by making an NACA 0025 fairing for the 1 1/8" dia shaft.

 

The APC props just need to be drilled out to 3/8" and a notch for the MK shear pin milled with a Dremel tool.  Pretty easy to do.

 

Lots of details here:

 

Denny Wolfe

 

----- Original Message -----

From: Bill Gow

Sent: Monday, December 14, 2009 8:27 PM

Subject: RE: [Electric Boats] Pitch of Kipawa Propeller

 

 


From: gregory_west2001

I had a bizarre exchange with the Kipawa propeller customer service number
today. I emailed the customer service yesterday to ask the diameter and
pitch of a Kipawa prop for a MK Endura 30/34 and received a response email
today with the diameter, which apparently is not a secret, and the statement
"We do not give out the pitch of the Kipawa Propeller."

When I called and asked them why in the world they would not tell me the
pitch on the prop, since it is what it is and since it is not a trade
secret, I was told that I could order one and measure it and return it if I
wanted but they would not give it out.

I am in still interested in knowing the pitch of the prop (without ordering,
measuring and returning one if it has a pitch I don't want). I have
variously seen the pitch online as being listed as 6" or 9". Does anyone
know the pitch of the Kipawa props? If so, and assuming Kipara did not have
you sign a nondisclosure agreement as a condition of the purchase, would you
let me know the pitch? Thank you.

[Bill Gow] Perfect timing! I just got a reply from them a couple minutes
before you posted this. I'm looking at props for the Minn Kota and
Motorguide electric motors as well. I'm wondering if one can use the bigger
motors with bigger after market props. This is what I got back;

"If your just looking for speed our props on average show a 10 - 15%
increase of speed over the standard Minn Kota Propeller."

__._,_.___
.

__,_._,___
Posted by at No comments:

Re: [Electric Boats] Re: Pitch of Kipawa Propeller

 

I concur about your assessment of kipawa. For something so basic as prop pitch to be considered "proprietary information" is totally disappointing. I have a minnkota powered dinghy and would be interested in trying different props, but based on Kipawa's banal policy I won't be interested in experimenting with their products. This is a shame because from some reports the kipawa product seems a worthy alternative option for the minnkota motors, but you can count me out.

Two enthusiastic thumbs down for kipawa inc.

Hans K



--- On Tue, 12/15/09, bosunj.rm <bosunj@rocketmail.com> wrote:

From: bosunj.rm <bosunj@rocketmail.com>
Subject: [Electric Boats] Re: Pitch of Kipawa Propeller
To: electricboats@yahoogroups.com
Date: Tuesday, December 15, 2009, 11:09 AM

 

Interesting that corporations have trained some so well that they don't automatically reject a company that won't give them the info they need to make an informed decision. Any company that acts like this doesn't deserve my money. Thank you for the heads up. I'll add them to the growing list of mostly Duhmerican't companies I won't do business with.

--- In electricboats@ yahoogroups. com, "marka97203" <marka97203@ ...> wrote:
>
>
> I've got a Kipawa 314 they sent for an E-30. It's 10" diameter. From
> root to tip is 2.5 inches. The blades are not twisted very strongly.
>
> Does that make pitch the sum of the three blades, or 7.5?
>
>
> For my own 650 pound all up 16 footer, the Kipawa prop did make a modest speed
> improvement - but nothing like the 30% better range Denny Wolfe reports.
> For that I had to add another battery.
>
> Mark
>
>
>
> On 12/14/09, gregory_west2001 <greg@...> wrote:
> > Does anyone
> > know the pitch of the Kipawa props? If so, and assuming Kipara did not have
> > you sign a nondisclosure agreement as a condition of the purchase, would you
> > let me know the pitch? Thank you.
> ;
> >
> > "If your just looking for speed our props on average show a 10 - 15%
> > increase of speed over the standard Minn Kota Propeller."
> >
>


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.

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Posted by at No comments:

[Electric Boats] Re: Pitch of Kipawa Propeller

 

As I posted my original question in this thread, I did forward a copy of my posting to the Kipawa customer service email address to let them know that I thought their policy of not being forthcoming on such a simple and otherwise public piece of information was a bad marketing practice. That was yesterday morning, and I have not received any response.

--- In electricboats@yahoogroups.com, Jason Taylor <jt.yahoo@...> wrote:
>
> I would go one step further. Email their sales/marketing people with a
> link to this thread and mentioning the number of people that are not
> going to consider Kipawa propellers *because* of that business
> attitude. Someone somewhere within their organization should know that
> refusal to provide real specs is costing them money and/or opportunity.
> Count me in the "not in a million years" camp.
>
> A satisfied customer will tell 10 people.
> A dissatisfied customer will tell 100.
>
> /Jason.

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Posted by at No comments:
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