Uncoated Import versus Techniks-Parlec PowerCOAT Collet Nuts - Put to the Test

Written and edited by Bernard Martin

PowerCOAT Collet Nuts provide up to a 75% increase in holding power!

One of the most important elements of the toolholding 'system' is the collet nut. Each toolholder "system" consists of a precision ER tool holder that comes with a special "Power Coated" high power nut that holds tighter than any other nuts.

According to Techniks, the 'Power Coat' nut is the secret to their high holding power. Because it holds so tight, the 'Power Coat' nut improves T.I.R., extends carbide tool life, and improves finish in heavy milling operations.

Techniks recommends that for best results always tighten the nut to the proper torque using a torque wrench with a tightening stand, and never over-tighten the nut because this can damage both the collet and the collet pocket.

To demonstrate the difference between an uncoated and coated collet nut, Mike Eneix, from Techniks did some testing.

He took an uncoated, imported nut and put it to the test against the Parlec PowerCOAT nut. Mike took them to the limit to see which one gives you more holding power.  Check out the video below!

What makes the difference?

As anyone knows who has changed a flat tire on their car, tightening down a nut on a 60 degree thread involves some friction as the mating metal surfaces interact.  That's why nuts can be a bit 'hot' to the touch when you take them off.  The objective with the "Power Coated" nuts was multifold:

First Techniks needed to reduce the coefficient of friction on the thread angle to enable more lubricity for the nut to tighten down farther. As we all know 'heat' causes metal to "grow" so what may at first appear to be tight, in fact, loosens, as soon as you stop tightening it.

Second they needed to make sure that the front surface of the collet that engages the shorter 30 degree taper on the front of an ER collet did not 'twist' as the night tightened down.

Both problems really involved reducing friction and through a combination of engineering tolerances and unique coating process we believe that we've found the most economical solution to eliminate the use of cheater bars and collet over torque. Here's what  they've found  out in testing the "Power Coated" Nuts:

• Up to a 75% increase in holding power
• Can extend tool life by 20% by reducing TIR
• "Engineered" balance for high speed machining

“Power Coat” is an innovative, permanent coating that increases clamping pressure of the nut up to 75% compared to standard ER nuts. More holding power reduces the chance of spinning the shank of the tool inside the collet, which can cause premature failure of the collet.