[hpv-boats] New shafts coming

[Mark Vermilion]

Folks,

I am about ready to order customized flexible cable shafts rated to  
200 in-lbs of torque. They are  two meters long, and each end will  
have a 12 mm ID connector with an off center cotter pin hole. The  
cable is 316 stainless steel, and it allows you, within a certain  
radius, to bend the shaft as needed, i.e. a 90 degree angle, or around  
objects.  They are secured about every foot or two to your boat with  
simple clamps (not provided).

This may not be the performance market's ultimate shaft solution, but  
it does solve a lot of issues related to alignment, the raising of the  
prop in shallow water, and the breadth of boat designs in which it  
would work. For example, you could have a straight chain drive of a  
large increaser ratio, and connect the cable shaft, then bend it 90  
degrees to the stern. Or if you need to snake a shaft around other  
immovable boat parts, it may work for you.

I do not have final pricing yet, but I think they will be around $215,  
U.S. shipping included. That's not bad when compared to a stainless  
steel shaft and flexible shaft connectors, especially if you need to  
go the U-joint route.

I really do not know how well these will work in various applications,  
but I thought potential new uses was worth the risk. It will be fun to  
see what implementations the creative DIY hpb builder will come up  
with. If there is a market out there, we may be able to provide custom  
lengths in the future.

Thanks,

Mark A. Vermilion

Marco Polo Boats, Inc.
Exploring the past and future of small boat design
1911 Smallbrook Drive
Troy, Michigan 48085
USA

www.marcopoloboats.com

Tel & Fax   1-248-434-4187



On Aug 26, 2010, at 2:53 PM, v garza wrote:

> Rick, lots of good info on material I don't know much about, Thanks!  
> I did use a 0.18" pultruded CF shaft sometime ago until it tangled  
> in a root and fractured. It was great, unlike anything else while it  
> lasted, for my particular gadget. I am trying for even thinner and  
> lighter using maybe one carbon mesh layer, since there is not a lot  
> of torque demand in normal conditions. The lighter the lever arm in  
> my application the better. I have also experimented with longish  
> tapered spinners fore and aft of the prop, made from lightweight  
> FLOATING material. Interesting advantages to these spinners when  
> combined with a lightweight shaft and prop, as it introduces some  
> upward forces that allow some degree of reverse, among other  
> things....
>
> Vic
>
>
> ----- Original Message ----- From: "Rick Willoughby" <rickwill at bigpond.net.au 
> >
> To: "HPV Boat" <hpv-boats at bikelist.org>
> Sent: Monday, August 16, 2010 9:26 PM
> Subject: Re: [hpv-boats] Sleeved Shaft
>
>
>> Vic
>> It could easily reduce to half nominal diameter.  The fibres will  
>> run  a little straighter so will increase buckling resistance but  
>> not so  much to torsional rigidity.
>>
>> If you only wanted to go to around 1/4" overall you might get 3   
>> layers on something starting at 1/8".  I think you would have to  
>> wait  for some initial cure before putting on each layer.  With  
>> epoxy you  can accelerate the curing by heating.  The other way  
>> would be to  place all layers dry and then really soak the shaft,  
>> working until  wetted out.  The fibres tend to form tiny needles  
>> that catch on  successive layers as they are slid on.  The more  
>> damage the more  needles.
>>
>> Rick
>>
>> Thanks, Rick you have given me a lot to think about.  Those are quite
>> impressive measurements.
>> How thin will the 1/4" mesh go when stretched tight on a rod, as I am
>> shooting for about 1/8" on the rod part. That way I can add  
>> another  layer
>> for strength if needed. Can I get small amounts of the equivalent   
>> epoxy in
>> USA, is my next question to research....
>>
>> Vic
>> --
>> This message comes to you via the hpv-boats at bikelist.org mailing  
>> list, sponsored by http://www,HuPI.org/
>> Visit http://bikelist.org/mailman/listinfo/hpv-boats to manage your  
>> subscription.
>
>
> -- 
> I am using the free version of SPAMfighter.
> We are a community of 7 million users fighting spam.
> SPAMfighter has removed 817 of my spam emails to date.
> Get the free SPAMfighter here: http://www.spamfighter.com/len
>
> The Professional version does not have this message
>
>
> --
> This message comes to you via the hpv-boats at bikelist.org mailing  
> list, sponsored by http://www,HuPI.org/
> Visit http://bikelist.org/mailman/listinfo/hpv-boats to manage your  
> subscription.