Prop struts

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Tony Hain
Posts: 299
Joined: Fri Aug 26, 2011 3:01 pm
Location: Queensland Australia

Prop struts

Postby Tony Hain » Thu Apr 30, 2015 10:36 pm

I believe I'll be running a 13 x13 prop. From what I've read on the forum a prop strut with a 8 1/2" drop will give me the best options if I find I need to re-prop to get the best output.
1. Would people generally agree with that?
2. I have not been able to find a strut with that drop on the Glen-L site. Could anyone recommend an other supplier? (I am in Australia but that doesn't matter as I have found that sourcing things from the States has been generally cheaper anyway.)
Regards
Tony
Tony Hain
"Never under-estimate the bounds of human stupidity" (Robert Heinlein)
and on a more optimistic note "nor the capacity for human brilliance"

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Aussie
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Joined: Wed Feb 10, 2010 4:31 pm
Location: Sarina Queensland Building 23ft Belle Isle

Re: Prop struts

Postby Aussie » Fri May 01, 2015 1:56 am

Hi Tony,

I have a 7 1/2 inch drop at 14 degrees that i bought from glenl.....well old aussie actually bought it for me...thanks dad....
I set it so that i had 14.5 degrees to the hull which gave me about 11degrees to the stringers...this will let me run the 13 inch prop with about 2.5 inch clearance from the hull.....would have to have a look at the product number but glenl should have something to suit...

Jamie

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Roberta
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Re: Prop struts

Postby Roberta » Fri May 01, 2015 5:04 am

I think the Glen L strut with the 7-1/2" is the 90-122. That is the one I am using with a 13-13 prop. Plenty of clearance for a 14" prop. This strut can be had with 10-12-14-and 16 degree angles. I believe mine is the 16 degree one on my Torpedo. Contact Gayle at Glen L and she can order it for you. It is no longer in the catalog, but still available through them.

Roberta :D
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo "The Glen L".

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Bill Edmundson
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Re: Prop struts

Postby Bill Edmundson » Fri May 01, 2015 6:58 am

Tony

I think mine is the 7 1/2" /14 degree. I run a 13x16 prop. I run a 1.23:1 reduction gear. In the end it equals out to a 12 or 13 pitch.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

Tony Hain
Posts: 299
Joined: Fri Aug 26, 2011 3:01 pm
Location: Queensland Australia

Re: Prop struts

Postby Tony Hain » Fri May 01, 2015 1:26 pm

So I guess by the time you leave the 1" spacing between the strut and the prop (1" prop shaft) and take into account the angle, then there would be actually more than 1" clearance for a 13" prop on a 7 1/2" drop?
Tony Hain
"Never under-estimate the bounds of human stupidity" (Robert Heinlein)
and on a more optimistic note "nor the capacity for human brilliance"

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Bill Edmundson
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Location: Birmingham, AL, USA
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Re: Prop struts

Postby Bill Edmundson » Fri May 01, 2015 1:59 pm

Tony

As I remember, I have 1 1/2" clear. The thickness of a US 2x4.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

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Roberta
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Location: East Troy, Wisconsin

Re: Prop struts

Postby Roberta » Fri May 01, 2015 2:18 pm

Using the 7-1/2" drop, 16 deg strut, and 13" prop, I have 2-1/2" of clearance to the keel line. I used a 14 deg shaft log and have an 8 deg down angle Velvet Dive transmission.

I like the 90-122 strut because it has a very large base and long shaft housing. I used one 4" Blackfish bearing that is cut in half and installed on each end.

Roberta
Roberta "Queen of the Boat Builders"
Built Zip "Oliver IV", Super Spartan "Jimmy 70", and Torpedo "The Glen L".

Tony Hain
Posts: 299
Joined: Fri Aug 26, 2011 3:01 pm
Location: Queensland Australia

Re: Prop struts

Postby Tony Hain » Fri May 01, 2015 5:48 pm

Well just did some drafting and calculating and it seems a 7 1/2" drop and a 14 degree angle is what is required. Thanks for everyone's imput.
Tony Hain
"Never under-estimate the bounds of human stupidity" (Robert Heinlein)
and on a more optimistic note "nor the capacity for human brilliance"


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