Don Terrill’s Speed-Talk

In the Seventies there was a metal finishing process, developed by William H. Davis of Tenafly, NJ, with the company Durasurf, Inc. headquartered at 75 Carver Ave., Westwood, NJ. After extensive searching, I can find no current info on any of this. My interest is from an old clipping from the April, 1976 issue of Hot Rod, Pg73+. This describes Davis' process of metal finishing via chemicals and abraisives and ultrasonics at an uncommon frequency and amplitude. The surface finish achieved, on such things as valves and valve springs, among many applications, was said to greatly improve fatigue resistance of these parts. Reportedly some racing teams were finding it useful.

Anybody here know anything about this. in searching, about all I can find is that Davis' trademark protection expired long ago, and that a William H. Davis of Tenafly, NJ died in the late Ninties, although there may be another by the same name, age 87, still alive, so I don't know. From what little I can gather, this was possibly a smart guy with a good process that has been discontinued and not picked up by any other outfit. I didn't see any patent info.

http://www.researchgate.net/publication ... _and_gears Possibly this general technique.

https://books.google.com/books?id=IleBq ... sm&f=false

I wonder if it is akin to the REM (tm) polishing process. We use a similar, albeit waterbased process on our gears, shafts and sliding clutches.

Yea sounds like the 70's version of isotropic surface finishing or REM as stated above.

https://en.wikipedia.org/wiki/Vibratory_stress_relief might be the uncommon frequency and amplitude (varying for different items). Two birds with one vibrating abrasive.

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http://www.dhmo.org/truth/Dihydrogen-Monoxide.html

"Better Things for Better Living...Through Chemistry." DuPont

Nasty stuff that DHMO, and incredibly addictive...

Probably not applicable, but I remember reading about guys clamping engine parts like heads, cranks, blocks and such to a great big adjustable vibrating table and "shaking" hell out of them to stress relieve them. They would tune the vibration frequencies to do this....

Just food for thought.

pdq67

Looks like Kevin hit the nail on the head! I believe that chemistry is still sold by Kale Auto Division. They sell the pure stuff, not the watered down version, as do some other dealers.

pdq67 wrote:Probably not applicable, but I remember reading about guys clamping engine parts like heads, cranks, blocks and such to a great big adjustable vibrating table and "shaking" hell out of them to stress relieve them. They would tune the vibration frequencies to do this....

Just food for thought.

pdq67

Still a widely used process today. http://www.meta-lax.com

Well, I looked at all of your links and references, and none of them sound to me like they are the same as Durasurf (which is not to say that any one of them might be equally effective or even better). www.remchem.com describes its process in such general terms as to tell me nothing. As for shaker tables, that's a whole different principle, whole-part stress relief rather than surface finishing. The late Joe Mondello became a big advocate of shaker tables (which operate at about 100Hz, not ultrasonic), as you can read about on www.mondello.com/page23.php

Given the age of the HRM article, it probably will take an OLD guy to tell us about this.

seattle smitty wrote:Well, I looked at all of your links and references, and none of them sound to me like they are the same as Durasurf (which is not to say that any one of them might be equally effective or even better). http://www.remchem.com describes its process in such general terms as to tell me nothing. As for shaker tables, that's a whole different principle, whole-part stress relief rather than surface finishing. The late Joe Mondello became a big advocate of shaker tables (which operate at about 100Hz, not ultrasonic), as you can read about on http://www.mondello.com/page23.php

Given the age of the HRM article, it probably will take an OLD guy to tell us about this.

You just have to go to Remchem's 1984 patent to learn more about it: http://www.google.com/patents/US4491500 You can follow their citations and also explore some of their later patents.

They don't specifically mention electropolishing which has been around a long time: http://palmettoplating.com/wp-content/u ... -Paper.pdf

https://www.google.com/#q=ultrasonic+electropolishing you can explore ultrasonic additions to electropolishing.

https://www.google.com/#q=ultrasonic+stress+relief ultrasonic stress relief.

A few dozens of lifetimes of study wrapped in there.

Thanks for all that, Kevin, I'll take a look.

I have read a few posts about Durasurf. Does anyone know what Durasurf and BMW motorcycles have in common back in the early to mid 1970's. I have read something about Durasurf putting there product on a BMW motorcycle. Does anyone have information about this?

pdq67 wrote: ↑Mon Aug 24, 2015 10:26 pm Probably not applicable, but I remember reading about guys clamping engine parts like heads, cranks, blocks and such to a great big adjustable vibrating table and "shaking" hell out of them to stress relieve them. They would tune the vibration frequencies to do this....

Just food for thought.

pdq67

I used to have a girlfriend that could do that...

I have come across a motorcycle from the mid 70's that has" Durasurf "painted on the fuel tank it appears to be professionally done. I'm looking for any information on this motorcycle and the conection to Durasurf.