reptilezs

anyone use one of these? we have one in the shop but it is manually activated. the press is a giant acme screw with a 3/8 drive to stick a ratchet in. is this method any better than grabbing parallel spokes? i usually just do the parallel spokes squeeze with some gloves on

mrrabbit 

1. This tool is quite fine to use as it meets the criteria of control - i.e., control in that you don't overdo it and collapse the wheel. It has been calibrated for the wheel in question to ensure the force applied is within the limits of the wheel AND achieves the desired stress relief. This tool is faster...

2. Hard parallel squeeze of folks is very inexpensive - you have your hands already assuming you are still alive - but takes longer per wheel.

=8-)

Kimmo

I have a feeling some folks who build a lot of wheels will start getting ideas after seeing this...

reptilezs

you guys want a pic of the one i have at work? pretty easy to make

reddog3

Yeah- where's the pics?

Rubato

Of course we want pictures.

bobotech

Neat tool. Looks like you could easily make one by building a frame for the wheels with a big cutout in the middle and using something to push the center of the wheel down. I wonder if you could even use something as simple as a lever?

mrrabbit 

Anyone can build one bobotech, the fundamental issue is the following:

"Control"

1. Determining the limits to operate in for a given wheel that is being built in volume...

AND

2. Ensuring the the minimal amount of stress relief is occuring to ensure a properly stress relieve wheel.

So testing, scale determination, and calibration is required as part of the tool design.

The benefits are - anyone can do it on the line with minimal training - AND it can function in a high volume environment. Like a spoke machine - it would pay for itself pretty quickly.


Using the hard parallel squeeze method works fine - but it's slower AND some folks back off on "hard" thinking they're going to damage the wheel - not realizing you'd probably bust your own fingers and palms or cry like a baby before you can do that - resulting in a wheel that still is not stress relieved.


One misinterpretation some folks have with Jobst is the belief that he is against the method picture in the video - manipulating the hub, OR the rim. The truth is he against it in the absence of controls to avoid destruction of the wheel.

=8-)

bobotech

What do you mean by "the absence of controls to avoid destruction of the wheel"? He doesn't like performing techniques that can possibly accidently lead to the destruction of a wheel such as using a lever and pulling down too hard on it?

I was thinking that you might want to use a scale of some sort to see how much leverage you are putting on the wheel. If you build the tool on a scale, you could tare the scale when the wheel and tool are on it and then when you pull down on the lever, the scale will tell you how many pounds you are applying. I wonder.

Kimmo

Yeah, I turn my hands to mush - I go around twice, almost as hard as I can, each of the two or three times I do it.

Pretty hard yards on the old starboard dexteriser there...

mrrabbit 

On occasion with 15g and the Ritchey Logic 2.0/1.7/2.0 and DT equivalents, the thin section of a spoke will split the knuckle of my left pinkie...leaving me walking around the garage for about 30 seconds yelling every expletive known to sailors...

It hurts like hell...

=8-)

reptilezs

here it is. the metal strapping is pretty thick. 3/16 or 1/4 inch. the plywood is probably 3/4 inch

mrrabbit 

Looks very nice - good choice of using plywood with rim reinforcement...

But the question is begged: How are you going to go about determining the limits of each particular wheel - and how are you going to ensure that you properly input a measured amount of force that will provide the needed stress relief WITHOUT the risk of collapsing a perfectly good wheel.

=8-)

reptilezs

it is nicely made by rolf themselves. the wall mount and hinged leg was our contraption though. yank on the cable and it pulls the leg up so it folds against the wall. not a clue on how to determine limits. i just crank till the spokes rip out of the rim..... j/k. i just do it by feel. i am well aware that the tool can generate a lot of force. still begs the questions of whether i am using too much or too little. the the video they blank out the digital read out, not sure what it measures, deflection or some force.

mrrabbit 

Typical tension meter use deflection of a given distance of material at a given guage to generate a number to be translated...

Wouldn't surprise me if a similar principle is in use...

=8-)

I also found myself wondering if your tool could be used to roll a partially inflated tire just short of roll-off to resolve a bead seating issue...what do you think?

=8-)

bbmike

One could use flexiforce sensor to measure the load: https://www.hoskin.qc.ca/uploadpdf/In...0f35db4439.pdf

mconlonx

Rolf? Champion of the paired spoke design in wheels? Think I'll pass on their tools...

bobotech

Why in the world is the pressure meter blanked out during the actual operation?

mrrabbit 

Because they believe the parameters they've tested for for establishing the proper force application for a given wheel is proprietary information...

=8-)

mrrabbit 

By the way, nice link...just another among hundreds that are stored on my server for their technical info value - just because I can...

Thanks!

=8-)

Bianchigirll 

That is why you have hands. Maybe some of the new >28 spoke wheels are different but back when I used to work in shop and we must have built hundreds of wheels with nothing more than a truing stand and spoke wrench. No fancy tension guage, no fancy gadget for 'stessing' and 'seating' all the parts. I would say we never 80-90% of them again and less than 1% ever had any issues and most were rider inflicted.