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Re: Who uses what.
By:John Monfoe
Date: 2/1/2001, 4:53 am
In Response To: Re: Just a question. (Spidey)

: Hi George;

: Why would you accept the math and agree the error is too much? Do you hold
: better than 2.94% volume accuracy or visually 30 thousandths of an inch
: (in graduations) when you mix 6 oz quantities (IF you mix that large a
: quantity . . . :))? If so, what kind of equipment do you use?

: I agree with you that someone who can't measure accurately probably can't
: weigh accurately either, but this stuff is not rocket science, and the
: tone of this thread does a disservice to the beginning builder. The mix
: ratio is NOT as critical as is being portrayed, otherwise the use of a
: mixing cup marked with a "Sharpy" would (by statements made
: here) be off so much as to preclude any hope of success. I say this
: because the thickness of the line produced and the viscosity
: "creep" would amount to far larger errors than are being
: discussed here - For the record, 2.94% in total volume with 11/12 lb
: specific gravity differences and a 2:1 mix ratio when a scale is used.

: Again, the advantage of a scale (even without regard to specific gravity
: corrections) is that essentially any quantity can be mixed as needed
: "on the fly" and the epoxy WILL cure, and at the mfrs. stated
: time & temp - - and probably more accurately than a visual mix ratio .
: . .

: Geez, do you have to throw creamed corn, George . . . ? :)

: Best Regards, Spidey

They all work well. The main patternshop I worked in used scales in grams and our rations were in the 12 to 1, 10 to 1 ratios, etc. General Motors pattern shops used pumps in 55 gal. barrels. The pattern shop that was an outsourse to Guide Lamp used balanced scales. One dash board would go for as much as $65,000 so there couldn't be any screw up using an inferior method of measuring. They all worked accuractly.

John

Messages In This Thread

Re: Just a question.
Spidey -- 1/31/2001, 8:26 pm
Re: Who uses what.
John Monfoe -- 2/1/2001, 4:53 am
Re: Just a question.
Dale Frolander -- 2/1/2001, 2:03 am