Tools advice

[Matteo]

Hi

May you suggest me a good electric screwdriver with digital (precise) torque setting and a torque wrench?

Both with some screw bits and adaptors.

Thanks

M.

[ThomasOK]

Hi

May you suggest me a good electric screwdriver with digital (precise) torque setting and a torque wrench?

Both with some screw bits and adaptors.

Thanks

M.

Pulled from a document I created to explain how to use a precision torque driver and the best one I have found to use:

In setting torques you will have to fine tune them by ear as the torque screwdrivers can easily vary by plus or minus 6% which is larger than the differences I find musically important. I use a Sturtevant Richmont CAL 36/4 for setting torque. This is also used by Fredrik Lejonklou, Paolo Nobile and many others, apparently including Linn. This driver is calibrated in both in/lbs and in Nm, which is the scale I use, and covers the range from .2 to 4.0Nm. This is a near perfect range for adjusting turntables as the lowest torque setting I have found so far is .2Nm minus 9 notches for the motor wires to the Radikal sensor board whereas the highest is 3.8Nm plus 1 notch for the bearing housing to the Keel. As to the notches there is a small flip-out handle on the bottom you use to adjust torque, which has a tab and a series of 9 notches that it can fit in to hold it in place. I label my settings by going to the nearest mark (.2Nm increments) and then count how many notches above or below that mark is the correct setting. Fredrik, Paolo and I have found that 1 notch (less than .04Nm) is audible on most settings with 2 notches making a clear difference. We have even had a few cases where we use a half-notch setting. Best bet to find a driver is either to google Sturtevant Richmont CAL 36/4 or check eBay for a used one -which is how I bought mine. New they sell for anywhere from about $140 to well over $200. On eBay they show up all the time and rarely go for over $50. I don't know of an electronic one that would work as well. The SR driver is one that breaks at a torque higher than what you set. In other words it will not torque more than what the setting is.

On the SR torque driver there is a clear plastic indicator that is convex to magnify the numbers on the scale a bit. There should be a black line in the middle of the bulge and that is the reference to use for the settings. I recommend adjusting it so the black line on the plastic is centered on the reference for the Nm setting nearest the one you want to try. As an example, if you were going to start at .8Nm you would center the black line on that and then flip the handle down such that it falls in one of the notches on the bottom. Since it can flip both ways one way should put it pretty much in the notch and the other way it would be on a land. Once you have located the proper notch you count the number of notches above or below (clockwise or counter-clockwise) to get to the place you want to be. So .8Nm-7 notches would have you finding the .8Nm mark and going 7 notches counter-clockwise. Hopefully this will give you the information to start working with it.

[Matteo]

Thanks Thomas

Very kind and useful

M.