Spoke tension meters / gauges - recommendations?

[Polar Bear]

A friend would like to borrow my jig and asked about a spoke tension meter.  Only ever being an amateur builder I do not have one.  Is there any value in buying a Park Tools TM-1 or would the panel recommend any other brand and / or model.   

I'd like to get something of decent quality and reliability though of course paying through the nose unnecessarily seems pointless too.

Experiences of any product most welcome.

Thanks.

[LittleWheelsandBig]

I have used several tensiometers over the years but now use an app.
https://yacf.co.uk/forum/index.php?topic=117807

[nmcgann]

Wow - that app is cool, I'll def try that for the next wheel I build.

I have the Park meter which works ok as far as I can tell (none of the wheels I have built using it have ever failed so I assume it works  ).

[Polar Bear]

Thanks for that.  There is an Android version of the app.  I'll look into it but I am still interested in mechanical gauge recommendations please.

[LittleWheelsandBig]

All of the mechanical gauges that I have used work fine and are basically interchangeable in function. Provided you don't drop the gauge and you can fit the gauge onto the spokes (more difficult with small wheels), the main issue is whether the measurement is accurate and/ or consistent. They all use the same basic principle, complicated by some aero spokes. The differences of reduced friction and tool stiffness are trying to gild the lily, given the much larger differences in straightness between rims, provided you are careful and consistent in how you use the tool.

[Kim]

I have a TM-1.  It seems to work fine (in as much that the readings are fairly consistent), apart from on my Brompton wheels, where there isn't enough spoke for it to fit properly.

[mzjo]

The cheapskate way, given the app is basically a tuning app, would be to use a tuning app (I have one for guitar tuning that gives the resonance of the string) of which there are several free on Android. The difficult part would be translating to a precise tension but if you just want to get all the tensions the same it should do the job. As with most of these things, the biggest ennemy to accuracy will be the quality of whatever bit it is that you are using in the smartphone (in this case the mic and whatever electronics are behind it).
I have never used a meter or a proper jig but i will have to try it to see if it works.

[Paul H]

As above. What are you using?
The kit I have access to includes the Park TM-1 gauge, it works fine if used with care, consistently placing the spoke on it, releasing it in the same way... I go round the finished wheel a couple of times and am satisfied with the result.
I prefer the iPhone app, doesn't seem to matter if you twang the spoke a bit different, the reading remans the same.  Some people can hear this without the app, I've seen several Spa Cycles demos ay York Rally, but I can't tell small differences even when they're pointed out.
Wandering into egg sucking territory, you can't stress too much to your friend that whatever they use consistent tension is more important than the actual reading. 

[LittleWheelsandBig]

The major point of measuring spoke tension is to check whether you are over-or under-tensioning the spokes. Most people can adjust spoke tensions to within 10% of each other (many can get a lot closer than that) by ear or feel but that process doesn’t actually tell you whether you have exceeded the maximum spoke tension for your rim. Unless you convert the sound to a tension by adjusting for the spoke gauge and length, you aren’t in a better position. For the trivial cost of the Spoke Tension app compared to any of the physical tensiometers, I can avoid a lot of hassle.

[rogerzilla]

I bought the Park one and its measurements confirmed I didn't actually need it in the first place.  This seems to be a common experience.  If you've built a lot of wheels, you know how tight a spoke needs to be for a particular application.

[S1966W]

There are a couple of longish, but fairly informative posts on the CTC forum regarding spoke tension meters;

https://forum.cyclinguk.org/viewtopic.php?t=138649&hilit=spoke+tension+calibration

https://forum.cyclinguk.org/viewtopic.php?t=54115&hilit=park+tools+tm1+spoke+tension&sid=d2c6083b851513e21645d55e3e4b518d

I am not a professional wheelbuilder by any standards but have knocked out over a dozen wheels so far, none of which have let me down. However they have all been fairly heavy duty rims and I usually just wind up the tension until it starts to get hard to turn the 'spokey'.

I do have a Park Tools TM1 but have found it fairly inconsistent in use and not really necessary. I have found the angle of use of the instrument and the 'release' technique when engaging a spoke can all make a 'couple of notches' of difference to the obtained reading. I did fabricate a simple calibration jig which worked quite well. The calibration screw on the TM1 which sets the spring tension did not have that much effect from one extreme to the other (i.e screwed right in or right out).

Hence, in summary - not really recommended. For professional wheelbuilding, I think you'd have to shell out for something higher end and considerably more expensive.

[BFC]

I have a TM-1, brought when exchange rates were a lot better than they are now. The supplied look up table is comprehensive and correlates with reality, feel of spokes/nipples and "factory" wheels, the spoke size gauge is redundant for me (I use digital verniers).

I also have a posh looking chinese unit with digital dial gauge (ZTTO TC02) which cost less than the TM-1. Photo copy look up table is pretty sparse and does not correlate with the park gauge or reality. Mechanics are more consistant and less user influenced than the TM-1, but more of a pain to fit in high spoke count wheels due to thicker material.

I use them more for checking consistency, helps avoid differences between trailing and leading spokes which can easily happen on stiffer rims without showing on the wheel jig (jig is fitted with dial gauges). This is the greatest problem to spot using ping test methods due to the whole wheel tending to resonate when at full tension, and I have a radio in the workshop.

I also check all wheels I build/rework with a tyre fitted and fully inflated for trueness and spoke tensions before and after a thermal cycle (in with the oil boiler in winter, solar powered in summer).

Some rims specifiy a maximum spoke tension (eg Mavics), others specify a minimum spoke tension with the tyre inflated (eg Pacentis). Between the two I get a nominal target range that I want all spokes to be within both with tyre off and on.

[Polar Bear]

I have been offered a TM-1 at a reasonable price and have decided to take advantage.  My friend is a former lab tech and loves tools and gadgets.  We'll learn how to use it together I expect.

[Jodel]

I have a Park TM-1 and am quite happy with it.  It is very good at checking for an even balance of spoke tensions, it is less good at measuring the actual tension.

I have just rebuilt a hub motor rear wheel destined for use on a tandem, so I wanted to ensure (as far as possible) that the spoke tensions were in the correct range.  The hub flanges were quite narrow at 38mm and as there is room (about 10mm to play with) between the tandem dropouts to move the whole hub around using spacers, I tried to keep the dish as shallow as possible.  This helped keep the difference in tension between the drive side and non-drive side spokes to a minimum.  Additionally, I had to lace the wheel as a single cross as the hub diameter is too large to permit a two or three cross pattern.

I had checked my TM-1 against a couple of other pairs of handbuilt wheels and the readings seemed far too high.  I decided to make up a rather Heath-Robinson test rig using a 150Kg digital hanging scale which let me apply a range of tensions to the Sapim Strong spokes I was using in the wheel.  As I had thought, the TM-1 was over-reading by quite a bit, especially at the higher tension end of the scale, so I just noted down the TM-1 reading of the actual tensions and used my own 'translation' of the TM-1 scale.

For the occasional wheel-builder, I think the TM-1 is worth having.  If you are consistent in the way you use the TM-1, the readings as you go round the wheel are very repeatable.  I'm sure it helped me get closer to an evenly tensioned wheel than I would have been able to achieve otherwise.  I did try using the Android phone tension app, but for me it was very inconsistent and I preferred using the TM-1.

[iandusud]

The cheapskate way, given the app is basically a tuning app, would be to use a tuning app (I have one for guitar tuning that gives the resonance of the string) of which there are several free on Android. The difficult part would be translating to a precise tension but if you just want to get all the tensions the same it should do the job. As with most of these things, the biggest ennemy to accuracy will be the quality of whatever bit it is that you are using in the smartphone (in this case the mic and whatever electronics are behind it).
I have never used a meter or a proper jig but i will have to try it to see if it works.

I have been building wheels for 40 years and in that time have built thousands of wheels and have never used a spoke tension meter. However, most of those wheels were built in the 80s when spoke counts were mostly 36 or 32 on most wheels. The more recent trend for much lower spoke counts has made me rethink this and so when replacing a rim on one of my DT Swiss wheels I used a tuning app to measure the frequency of the spokes (DS and NDS) before unbuilding the wheel thus allowing me to replicate the original spoke tension.

[rogerzilla]

The other change is that hubs and rims are different, and generally worse.  Hubs are sometimes CNC machined, not forged, and you can rip off chunks of the flanges with tight spokes (and a bit of salt corrosion). Rims are hard anodised or have eyelets that corrode galvanically with the rim, and are more likely to crack around the eyelets.

In the old days, you put in as much tension as you could, maybe half a turn short of making the rim into a pringle.  Now rims are wider, they will not fail reversibly through Euler buckling, but will be permanently damaged instead if you overtension.  The nipples will usually round off or crack first, but there are a few rims out there with ludicrously low tension limits.