The Steamboating Forum

Hi Russ,

nice work, looks interesting. Do you have a link to the Amazon offer?

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Dietrich

Dietrich:
YES.

Here is for the digital display:

https://www.amazon.com/DIGITEN-Digital- ... 170&sr=8-1


And for the waterproof box:
https://www.amazon.com/dp/B07TYNYW1S?re ... tails&th=1


The display is available in different colors.
Any waterproof box will work, but the one above holds everything and provided solid mounting possibilities that met my needs.

The display can be powered by different DC Voltages . A 9V battery works just fine and fits in the box. It can easily be changed by removing the "top" cover (4 screws), which I mounted toward the engine. Easy access.
You will also need a waterproof power switch, and a connector for the battery. They are also available on Amazon, and elsewhere. I had them in my shop supplies.

Hope that helps.
RussN

Russ,

Thanks for the links! Much more pleasing than my calibrated bike speedo solution and not that much more expensive.

For anyone wishing to use a bike speedometer, here is my information:

All of the bike speedos I've fiddled with calibrate with a number that is the diameter of the bike wheel in milimeters. A 2682 mm
(33.6") wheel revolves 600 times in a mile. With this number (2682) entered into the speedometer the readout will be correct for r.p.m.

Almost!

It will be off by a factor of ten but I've not found that at all confusing and I'm easily confused.

The only real advantages of the bike unit are size (it is possible to hide a bike readout in an old gauge housing) and cost/availbility. These speedos are widely available and dirt cheap if you avoid fancy bike stores. And battery life. They last for years. Also weatherproof.

I like yours though.

Mike

Mike posted: "I like yours though."

Thanks, Mike. Me too.
It's simple, can be easily read in the dark, and its GREEN, which pleases me.
RussN

Hi Russ,

thank you for the links. I have ordered the parts.

Best wishes
Dietrich

Dietrich:
I look forward to seeing what you produce!
So many opportunities for creativity.
RussN

Hi Russ

Many thanks for that information on the tacho and the links. I will certainly get myself one of your kits but I have long buoycotted Amazon for their apalling labour practices. I suspect that the same items will turn up elsewhere.

On the topic of propellors I am toying with designs for a DIY small prop for the canoe project. I will be very interested to hear how you get on with the lovely Pat S casting.

Regards

Pete

Pete:
Here are the same digital display "kits" on EBAY:

https://www.ebay.com/itm/234271929898?h ... R_jB3vS4YQ

RussN

Russ,

Sometime please measure the total current draw. Adding up the numbers in the specifications gives a total of 30 mA which sounds about right but up in the order area you have to select a power input (only one selection allowed!) that is wildly higher.

I assume that this high number is just some default number but it would be nice to know for sure.

Also, the specs talk about a low limit of 120 r.p.m. Is this correct or will it read lower speeds?

Mike

Mike:
I will make the current measurements soonish.
I suspect the specifications are all over the place. I've read 400 mA, and the info with my display says 40 mA!
And operating range is supposed to be 10 rpm to 999 rpm, whatever that means besides the max the scale can read.

My first tests rotating the shaft back and forth indicate it does read certainly below 50 rpm or so.
I've not done specific testing, and will do so.
Just for you!
RussN