Document Zpdq42bdDnDkxx3rRm9yY5NZ

'J J Bestwall Gypsum Company FOR PaolfiCLtfV.NY DATE ATTENTION OF Mr. C. G. Shuttleworth ANSWERING YOURS CGs Mr. J, 0. Vaughey - Detroit Sales Mr. 1. Kaboos - Detroit S/R Mr. A. H. Ten Elshof - Grand Rapids Mr. J. E. Watt - Paoli FROM Grand Rapidas OFFICE aJBJECT Acoustical Plaster DICTATED BY E. Reverski - ink Rei I. C. Monroe Muskegon, Michigan Wes, Garvey - Plasterer Mr. Kaboos brought back to the Grand Rapids laboratory last Friday two samples of natural colored acoustical plaster from a job in Muskegon, Michigan, Ties. Garvey, plasterer. On November 26, 1958, we shipped L. C. Monroe 30 - b0 lb. sacks of natural color acoustical plaster and 10 bags of the special white. The 30 bags were shipped from two sacking periods, one on October 111 (K-lh) and the other on November 25 (L--25) When applying, the plasterers noted a difference in the two lots. K-lb had a T.C. of 252 cc and L-25 a T.C. of 300 cc. K-lb was lighter in color and finer textured, L-25 was darker and seemed to contain more of or a longer fibering. They preferred to apply th9 higher T.C. L-25 material. Mr. os asked if I would send the samples on to Paoli so they are being sent along ether acoustical samples I believe the difference in the acoustical of the two days to be due mainly to a difference in the perlite. It is conceivably within the bonds to be expected in perlite variation. Paoli may have a different opinion after examining the samples. Messrs, Ten Elshof, Shuttleworth and Watt Only; At first, due to the longer fibers, I thought extra asbestos was added to the L-25 sacking period or the asbestow varied. Assuming a Basis of 100 Lb3. Acoustical: There is 27.2 lbs. of asbestos per 100#. 300 lbs. - 252 lbs. = 1*8 lbs. variation in water of the job samples. Assume the asbestos to have a T.C. of 275 cc, then 27.2 lbs. will carry 71.5# of water. At a max. T.C. of 3b0, the asbestos will carry 93.7 lbs. of water. 93.7 - 71.5 r 22.2 max. difference in T.C. that could be obtained by the asbestos while variation here is I48 lbs. Since this is not 1/2 of the variation obtained, I had to discount the asbestos as being the malfactor. Also, as to improper weight of asbestos going in per charge, when we got over to the*ite, the T.C. dropped from 300 and 298 to 252 cc on November IIj 15*58. This was all on the same day and since 8l--3/b lbs. of asbestos is addsd oer charge, I could not see an error in the quantity of asbestos added. It may be a combination of both asbestos and perlite to change the T.C. The puzzling thing is the difference in appearance of the Jj-2$ acoustic in that it is darker and appears more fibrous. The T.C. range of acoustic used on the Kalamazoo job was as follows* (Two lots were shipped also) The J-22s - T.C.3 ran 260-250-260 and 255. The K-lbs were* Natural 2bb cc and the whites were 260-252-268-260-268-2 76 and 280 cc. Along with the job samples, we sent our retained sample of the 2nd charge of L-25 with a T.C. of 300 cc and a sample of the white acoustical made L-25 with a T.C. of 252 cc. SGP 0018962