The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

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NATURAL ANKLING
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by NATURAL ANKLING »

Hi,
Bend, length or less accurate resonant frequency.
Later will vary depending on type of build, spokes and other components, and spokes touch too.
The former is easiest to measure.

I don't own one but spoke gauge must be included in calculations for mechanism/chart?
NA Thinks Just End 2 End Return + Bivvy - Some day Soon I hope
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Des49
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Des49 »

Sweep wrote:Thanks des - look forward to hearing more/seeing pics.


OK a few more details and pics. I ordered it early March 2018, received it end of July 2018.

I decided to upgrade to the linear slider option, an extra 75 Euros. I did not have to but apparently he had a small no. of these sliders in stock from a cheap batch he obtained a few years ago and they cost 250 Euro if ordered new now. Bit of unnecessary extravagence maybe, but sounded like a bargain so I ordered this! Payment was on order via PayPal, a fair amount of trust involved but that's how it is.

Various colour options are available, but in practice I didn't have any choice at the time. The case I brought myself, the tool arrives in a cardboard box.

Total cost for me was 210 Euro plus 10 Euro for postage.

In use it is lovely, very smooth, repeatable readings and gorgeous to look at! I use the mm side of the dial, on the other side it is calibrated in spoke thicknesses, but I find this less accurate to see and there is no 1.8mm line which is my most common gauge.

I find I can't always zero the gauge with just one hand (tend to use it in my left), sometimes needing to give a little tweak to the dial with my right hand. But I have fairly small hands so others may not find this the case for them. Or often I do not bother to zero it, just mentally adjust the reading from the starting point.

Well pleased and one of those beautifully engineered items that makes it a joy to use. Wish I had more time to use it, maybe this winter as I have several wheel and bike projects awaiting.

Tensiometer001.jpg


Tensiometer002.jpg


Tensiometer003.jpg
PhilD28
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by PhilD28 »

Nice pics. I’ve used mine to build about 60 wheels now, everything from heavy expedition to lightweight race wheels and I can’t really imagine a better tool for the job. Even with the standard slide, I find mine very smooth and totally repeatable. I also use the standard mm scale, definitely more accurate. You won’t have any problems with this tool. Mine was about 125 euro about 3 years ago so his prices are slowly creeping up.
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Sweep
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Sweep »

I fear I can't justify buying one it but it is truly a thing of beauty.
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Des49
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Des49 »

PhilD28 wrote:Nice pics. I’ve used mine to build about 60 wheels now, everything from heavy expedition to lightweight race wheels and I can’t really imagine a better tool for the job. Even with the standard slide, I find mine very smooth and totally repeatable. I also use the standard mm scale, definitely more accurate. You won’t have any problems with this tool. Mine was about 125 euro about 3 years ago so his prices are slowly creeping up.


Great glad you feel that way too, it feels like a tool that should out last me.
Samuel D
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Samuel D »

Thanks for the update and photos, Des49.

My Wheel Fanatyk tensiometer came with a conversion chart saying a deflection of 0.35 mm on a 1.8 mm thick spoke equalled a tension of 97 kgf. In 2018 this chart was revised for reasons I forget, now saying 0.35 mm deflection equalled exactly 100 kgf (not a question of rounding; other values on the new chart are given to three significant figures).

How do these figures compare to yours? I’m wondering if the springs are of the same strength. I guess they’re at least similar, based on the scale of the dial gauges chosen.
Des49
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Des49 »

Samuel D wrote:Thanks for the update and photos, Des49.

My Wheel Fanatyk tensiometer came with a conversion chart saying a deflection of 0.35 mm on a 1.8 mm thick spoke equalled a tension of 97 kgf. In 2018 this chart was revised for reasons I forget, now saying 0.35 mm deflection equalled exactly 100 kgf (not a question of rounding; other values on the new chart are given to three significant figures).

How do these figures compare to yours? I’m wondering if the springs are of the same strength. I guess they’re at least similar, based on the scale of the dial gauges chosen.


The table I have states 100kgf is a deflection of 0.41mm for a 1.8mm spoke. I actually hung weights from a spoke from the batch I had and measured the deflection before I started. It was close enough if I remember, haven't got access to my notes at the moment though.

Hanging weights from a spoke is a bit of a hassle to check calibration, so I have brought a 150kg digital scale and intend to make up a wooden frame and eye bolt contraption to measure spoke tension before my next batch of wheel building. In reality I am unlikely to get around to this for a couple of months at least, though I do seem to have a wheel that may need a new rim sooner.
colin54
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by colin54 »

This video came up on my youtube feed this morning, Jim Langley checking the build quality of some
newly purchased wheels, it shows the Wheel Fanatyk meter being used @9min 39seconds in .
Seems like an logical and easily understandable list of things to check on newly bought wheels, worth watching the whole video, I found it interesting and informative.
https://www.youtube.com/watch?v=Wb73si7WD-k
The link seems to start in the middle of the video on my computer, you may need to 'rewind'...
Jim's site:- https://jimlangley.net/index.html
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Samuel D
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Samuel D »

Des49 wrote:The table I have states 100kgf is a deflection of 0.41mm for a 1.8mm spoke.

So the spring in the Wheel Fanatyk model is a little weaker. If the spring is weak enough, the deflection becomes so low that the spoke’s bending stiffness does not need to be taken into account. Then you can ditch the different tables for each spoke gauge or, ideally, mark the dial scale or digital readout in units of tension.

But since neither of these models quite achieve that, I suppose small differences in spring strength are meaningless.

Yep, good video, colin54. I like Langley’s unhurried but organised style.
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NATURAL ANKLING
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by NATURAL ANKLING »

Hi,
How do you calibrate your tool?
Would you even bother?

https://www.wheelpro.co.uk/support/tensiometers/
NA Thinks Just End 2 End Return + Bivvy - Some day Soon I hope
You'll Still Find Me At The Top Of A Hill
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Samuel D
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Re: The Wheel Fanatyk Jobst Brandt design tensiometer (photos)

Post by Samuel D »

No calibration for me. Maybe after a couple of decades of my light use, but even then I’d bet there’s not much in it. The tool has features to minimise the influence of friction. The spring shouldn’t change noticeably over time. So where would a real need for calibration arise?

From that article:

“I had an issue with a wheel built with DT Competition spokes. All my experience told me the tension was right yet the DT tensiometer said it was way too low. It took a while to figure it out and the reason was the spokes were made undersize at 1.75mm instead of 1.8mm (this is probably within the spoke manufacturing tolerances). There was no way of telling the true tension because the readings from the DT tensiometer are cross referenced to tables and the table assumes your DT Competition is made to 1.8mm.”

Seems to me you’d get pretty close by subtracting 0.05 mm from the measurement and reading off the chart for 1.8 mm spokes at that value (or better yet, splitting the difference between the chart values for 1.7 mm and 1.8 mm spokes, still subtracting the 0.05 mm before reading the tension values).

But this highlights another benefit of the Jobst Brandt design: it measures deflection from the same side of the spoke as the spring force is applied, so precise spoke thickness doesn’t matter. Therefore you don’t have to measure it or worry about it.
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