Going deeper into the rabbit hole…

Latest creation of a tool to check/calibrate spoke tensiometer. It’s pretty simple tool as below:

A piece of square tubing with attached digital scale at one end and bracket on the other which allows to (precisely) tension spoke and calibrate tensiometer.

The “scale end” is pretty self explanatory. Just a digital scale attached to tubing. On one side the scale has got soft aluminium plate, with drilled 2.5mm holes, to keep spoke head (pretending to be hub flange).

On the other end of the bar is a bracket which allows to put a tension by turning the nut.

Why did I make it? I bought tensiometer some time ago. The tensiometer is not from the well known company, but a cheap copy (£17), which however IMHO is made better than original(!). It came with a table of tensions and instructions how to correlate reading with spoke dimensions, but I didn’t trust it whatsoever. So the calibration tool is a really cheap project, but effectively making even cheap tensiometer equal to fancy “blue one” ;-). The most expensive is the scale, which is around £15. Rest is just a square tubing (£4) and a couple of bolts to put it together.

Now the real life example. Smashed 650B wheel (bent rim). I ordered a replacement rim – DT Swiss G540, and decided to not reuse old spokes (2.0mm), but instead go for 2.0/1.8 butted ones.

On the rim you can read: “maximum spoke tension 1200N”, which is around 122kg. I set up the jig and I tested both spokes. Ordinary 2mm spokes ~122kg tension – reading from tensiometer 28.5. Butted 2.0/1.8, same tension – reading around 25.5-26.

There you go. Still, probably the most important, is to have as close to equal tension around the wheel as possible, but is nice to know where the limit is, as “tight” wheels are not going out of true that easy. Not mentioning, that to me the tension scale (reading the deflection from the tensiometer) looks logarithmic (I need to check it). Anyway, let’s simplify. That means, if let’s say, 40kg is 15 reading from tensiometer and 60kg is 20 doesn’t mean that 80kg will be 25 (20+5).

Keep’em rolling!

Wheel building time

This has been bugging me for a long time. Finally I splashed some money and dedicated some time to wheel building gear. Essentially I combined some DIY tools with more expensive bits. So far I managed to just try it, but looks like all will work great together.

At the moment I have a very basic truing stand from ParkTool (TS-8). Which does the job, but ultimately I want to make my own one (second covid lock down… stay tuned). The rest of the gear I’m pretty happy with and goes as follow:

The most expensive bit in my weaponry is from now on Hozan – spoke threading tool C-702-22 with heads for 13, 14 and 15 gauge spokes.

So far I can’t say anything about usage that much, as really I did some testing only, but quality looks second to none. I’m big fan of Japanese engineering, this is one of the finest example. I havd really a choice, between Weldtite (cyclo) threading tool, and Hozan, but after watching some photos and videos, I decided to splash some more money to have it from Hozan. Speaking of the purchase. I ordered it from a place called Plaza Japan and took 6 weeks to deliver it to UK. Not too bad as purchased during lockdown. The only annoying thing is the duty and other crap, like handling fee, etc I had to pay (fricking £69!). All in all the tool was 20 quid shy of £300. Bloody expensive, but I have what I wanted. As a bonus, the original box, came wrapped in Japanese newspapers, so we tested google lens. Amazing and exotic 😉

To that I finally added a DIY dishing tool. I was sick and tired of other methods (two beer cans and coins etc…). Really self explanatory how I made it, if you look at the photos. I had all the alloy pieces already (leftover from other projects). The job was really to cut with angle grinder slots for adjusting to different wheel sizes. I’m quite happy how it works.

Final bit, which makes the whole building procedure faster are nipple handling tools. After googling a bit I decided to go for IceToolz nipple pick. I bought two of them. One will be used as per original design – to pick up nipple and place it initially on the spoke. The second one I modified slightly to act as a nipple driver. Literally replaced the spring with a piece of wire (I had to drill slightly bigger hole). This way I can use it alone like that to turn a nipple (even without a handle) or put it on an electric screwdriver if I need to.

Future project (apart from truing stand) I’ll make a spoke tension calibration tool. I already have a digital scale up to 200kg. All I need to figure out is a frame and spoke/nipple clamping method. This way I can calibrate my cheap Chinese spoke tensiometer quite accurately without relying on the provided table, which (I got feeling) is not really precise 😉

Stay tuned, and keep’em rolling.