Metal finishing Q&As since 1989

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Low Friction Metal Clothing Racks

I am the general manager of retail clothing stores that utilize clothing racks made out of 1" square tubing. After fabrication we have always painted the racks with enamel and than sanded the edge where the hangar slides. At this point we have to wax this surface extensively in order for the hangar to slide freely. This works but requires a lot of maintenance. Do you know of any product that could be applied to this surface to promote the permanent slick (low friction)effect? To be applicable it would need to be fast drying with the ability to apply by hand.

Rusty Parrish
Five Star Thrift - Arlington, Texas
2003

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You are obviously limited from using graphite or oils. You might consider specifying nickel-chrome plated racks instead of painted racks, and you'll never have to worry about the problem again.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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You could always use nickel plate with a chromium overlayer. It is also possible to coat the chromium with a very thin layer (monolayer) of PTFE by sintering it, but that needs some skill and specialised equipment. There is also another material called PPS (Polyphenylene sulfide) that has similarly low coefficients of friction, so that may be of interest to you. I have also seen a chromium deposit that has micro sized (or even nanosized) particles of diamond co-deposited with it. This was on a hand saw blade and it had fantastic effects on its ease of use. I think it was done by a company in Switzerland or France.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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2003

Hi Rusty,

l. Ted's idea sounds good !

2. Another idea is to use a 2 component Urethane paint, NOT the regular so-called (semi) urethane paint you buy in the paint store. This will give you a very hard, glossy and abrasion resistant surface. Not cheap, however !

3. If possible and if this is feasible for you, go and approach a thermoplastic fabricating shop. You say that you are using 1" square tubing ... ah, that's O.D. is exactly, funnily enough, as the I.D. of 1-1/4" Sch. 80 PVC pipe. In other words 'they', if competent enough, should be able to heat up the pipe and slide it over the bar. Upon shrinking it should fit on fairly tightly but the bar will now be a little 'larger' than 1" square! They might suggest using l" Sch. 40 or series piping which would fit on very tightly.

Food for thought, anyhow.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).