Trucite

[Marci Be]

I am helping a friend refurbish a knee mill it's a no name Chinese, that originally had chromed (knee/saddle ways) the chrome was removed using muriatic acid but the guy took no readings as to the thickness of the chrome (I figure about 10 thousand but that's a guess) My question is. how would one determinate the correct thickness of Trucite to use?

Marci

 

[Richard King]

If it was scraped fairly good before it was chromed put in back together with the gib slid in so it is even with the big end and the back of the saddle.. As if it was when new. Buy some plastic shim stock like Argus color shims. Cut and then shim up all 4 corners and on the gib and positive side of the dovetail. Each shim approx 3/4" wide and 2" long. Shim it up using the same size thickness until the saddle is tight. I doubt the chrome was that thick. Usually they are flash chromed and I would think .003" tops.

If the ways had lousy scraping on it. Scrape the cast iron first. You remember "Pre Qualify" it or rough scrape it before you Rulon / Turcite it. I would want you to put in a minimum of .030" or what the Asians put on .047" Rulon /Turcite, so you may have to mill a little off. Remember to add in the .003 to .005 for the epoxy.

Rich

 

[Marci Be]

If it was scraped fairly good before it was chromed put in back together with the gib slid in so it is even with the big end and the back of the saddle.. As if it was when new. Buy some plastic shim stock like Argus color shims. Cut and then shim up all 4 corners and on the gib and positive side of the dovetail. Each shim approx 3/4" wide and 2" long. Shim it up using the same size thickness until the saddle is tight. I doubt the chrome was that thick. Usually they are flash chromed and I would think .003" tops.

If the ways had lousy scraping on it. Scrape the cast iron first. You remember "Pre Qualify" it or rough scrape it before you Rulon / Turcite it. I would want you to put in a minimum of .030" or what the Asians put on .047" Rulon /Turcite, so you may have to mill a little off. Remember to add in the .003 to .005 for the epoxy.

Rich

Thanks Richard I will do that