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View Full Version : Best Place To Get Your Crank Calibrated?


Fearsome Forehand
05-04-2012, 08:23 PM
Okay, no dirty jokes, please. :)

I'm aware of the place in Missouri? Is that the only place that does calibration/servicing of cranks? How much do most places charge?

sstchur
05-04-2012, 09:07 PM
Okay, no dirty jokes, please. :)

I'm aware of the place in Missouri? Is that the only place that does calibration/servicing of cranks? How much do most places charge?

Typically you'd do this yourself with a calibrator. They come in multiple flavors. I have a digital one, and a non-digital one. But basically you connect it to your machine and pull tension and see if your crank is high or low. Then you can usually adjust a few screws to increase or decrease how much it's pulling. I've never heard of actually taking it somewhere to have it calibrated unless something is really really fowled up, in which case, sending it back to the manufacturer for servicing might be the thing.

fortun8son
05-05-2012, 12:07 AM
Definitely DIY.
Piece O' Cake.
You can use a Gamma Calibrator or a fishing/luggage scale.

dancraig
05-05-2012, 01:36 AM
Best Place To Get Your Crank Calibrated?

Your house. :rolleyes:

dancraig
05-05-2012, 01:38 AM
servicing of cranks?

http://www.tennismachines.com/tennismachines/index.html

mikeler
05-05-2012, 04:14 AM
It's pretty much self service once you get married and have children. Oh, your machine crank? Same answer.

KerryR
05-05-2012, 07:29 AM
If you want it OVERHAULED, send it to Tennis Machines. Otherwise DIY. I have the Gamma non-digital calibrator, and am happy enough with it's accuracy. I've found that my Unique SportsTension Meter also works reasonably well, and it has other uses, which is nice.

Fearsome Forehand
05-12-2012, 10:48 AM
Okay, as advised I went the DIY route.

I purchased an electronic luggage scale for about $8 delivered on the auction site. It is of surprisingly good quality for the price.

The scale seems fairly accurate. It consistently indicates my machine pulls about 5 pounds less than the dialed in tension. (This is based on the initial reading not the gradual drop off reading.)

I used a method similar to this. I used poly string as I have no kevlar around.

http://www.eagnas.com/store/product_info.php?products_id=240

Would I get a more accurate reading with kevlar as opposed to pre-stretched poly?

KerryR
05-12-2012, 11:01 AM
Only if you see the tension drop fairly significantly over a shortish time as the string stretches. If the string is fairly 'worn out' (most of the elasticity gone, easy w/ poly's), I'm sure the tension won't drop much. It only really matters if the tension drops so quickly that you can't get a reading at the point the tensioner reaches it's tension.

Fearsome Forehand
05-12-2012, 11:08 AM
Does kevlar yield a constant reading. No drop off at all?

MAX PLY
05-12-2012, 11:19 AM
I use kevlar on my calibrator (Prince digital--sorry, they no longer make)--no meaningful drop off. Also wears forever.

KerryR
05-12-2012, 11:29 AM
I'm sure Kevlar is the best solution. But, unless you do hybrids with it, you probably won't have any, and it'd be kind of expensive to buy a set when other strings suffice.

My gamma spring based calibrator came with what appears to be 15g syngut on it. I just use that, and pull several times. After a few pulls and re-pulls, the string is stretched out enough that the scale doesn't drop after lock out, and I get a reliable reading. I'm not concerned about the teeny drops in tension a quality digital scale would show, I just want to be accurate to within 1/4 - 1/2 pound, which is probably about as accurate as the dial on my LO machine would allow anyway.

Eventually I'll re-tie the thing with stretched out poly. I'll probably never have any reason to have kevlar.

MAX PLY
05-12-2012, 03:52 PM
Couple of options to get some kevlar: Check for any scraps kept by local shops. Also I think a couple of off brands (eagnas) has kevlar for 5 bucks a pack--a lifetime supply for a calibrator. But you are right, many strings will suffice.

4sound
05-13-2012, 08:20 PM
Digital fishing scale works great.

zapvor
05-13-2012, 08:39 PM
It's pretty much self service once you get married and have children. Oh, your machine crank? Same answer.

hahahha nice