Paint Technology and Tests

by Henry A. Gardner

CONDENSED REPORT OF INSPECTION OF “1907” TEST FENCE

Fargo, North Dakota, Nov. 19-23, 1909

Test No.	FORMULAS																																						REPORT OF CONDITION
	pigment																						vehicle
	Cor- roded White Lead		Sub- limed White Lead		Zinc Oxide		Cal- cium Car- bonate		Alu- minum and Magne- sium Sili cate		Barytes		Silica		Inert		Magne- sium Sili- cate		Cal- cium Sul- phate		Zinc Lead		Lin- seed Oil		Tur- pen- tine Drier		Tur- pen- tine and Japan		Water		Turpen- tine and Ben- zine Japan Drier		Drier		Vola- tile Oil		Ben- zine		Chalking	Checking	Hiding Power	Color	Condition for Repainting
1	30		—		70		—		—		—		—		—		—		—		—		93		7		—		—		—		—		—		—		Medium	Considerable with lateral cracking	Fair	Fair	Poor surface; too hard
2	50		—		50		—		—		—		—		—		—		—		—		86		—		10		4		—		—		—		—		Medium	Considerable with lateral cracking	Good	Fair	Rather poor
3	20		20		50		10		—		—		—		—		—		—		—		90		—		—		—		10		—		—		—		Bad	Medium—scaling some	Good	Good	Fair
4	48	.5	—		48	.5	3		—		—		—		—		—		—		—		83		—		—		—		17		—		—		—		Medium	Considerable with lateral cracking	Good	Good	Medium
5	22		—		50		2		26		—		—		—		—		—		—		90		—		—		—		—		10		—		—		Slight	Slight	Good	Good	Good
6	—		—		64		—		—		36		—		—		—		—		—		98		—		—		—		—		—		2		—		Medium	Considerable	Medium	Medium	Fair
7	37		—		63		—		—		—		—		—		—		—		—		85		13		—		2		—		—		—		—		Considerable	Present; long cracks	Fair	Fair	Poor
8	38		—		48		—		—		—		14		—		—		—		—		91		9		—		—		—		—		—		—		Slight	Surface checking	Good	Good	Fair
9	—		—		73		2		—		—		25		—		—		—		—		66		—		—		12		22		—		—		—		Not evident	Considerable with lateral cracking	Medium	Good	Medium
10	44		—		46		5		—		—		—		—		—		—		—		86	.0	12	.5	—		1	.5	—		—		—		—		Medium	Very slight	Good	Good	Good
11	50		—		50		—		—		—		—		—		5		—		—		78		22		—		—		—		—		—		—		Slight	Lateral cracking	Fair	Fair	Fair
12	60		—		34		—		—		—		—		6		—		—		—		91		7		—		2		—		—		—		—		Considerable	Present with slight cracking and scaling	Fair	Fair	Not very good
13	—		60		27		3		—		—		—		—		10		—		—		90		—		—		—		—		10		—		—		Medium	Surface checking only	Good	Good	Good
14	25		20		25		5		—		—		—		—		—		25		—		90		—		6		—		—		—		—		4		Considerable	Considerable with lateral cracking	Medium	Fair	Medium; some washing shown
15	—		20		40		10		—		—		—		—		—		—		30		90		—		8		2		—		—		—		—		Medium	Medium	Good	Good	Medium
16	33		—		33		—		—		34		—		—		—		—		—		90		—		10		—		—		—		—		—		Medium	Slight; some shelling	Fair	Good	Medium
17	100		(Type		A)		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		Bad	Alligatoring; deep checking	Good	Fair	Poor
18	100		( „		B)		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		Bad	Alligatoring; deep checking	Fair	Fair	Poor
19	100		( „		C)		—		—		—		—		—		—		—		—		10 gal. oil reduction								—		—		—		—		Bad	Deep	Good	Fair	Poor
20	—		100		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		Considerable	Slight	Good	Fair	Fair
21	—		—		100		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		—		Not evident	Considerable; slight cracking; scaling	Fair	Good	Poor
22	—		—		—		—		—		—		—		—		—		—		100		—		—		—		—		—		—		—		—		Medium	Lateral cracking; split	Good	Good	Fair
23	100		(Type		C)		—		—		—		—		—		—		—		—		51⁄2 gal. oil reduction for priming																Bad	Medium deep	Good	Good	Fair
24	37	.51	7	.84	25	.87	20	.36	—		—		8	.42	(Michigan Seal White Lead)										—		—		—		—		—		—		—		Considerable	Slight; lateral cracking	Fair	Good	Good
25	38	.95	4	.81	33	.58	19	.48	—		—		3	.18	(Railway White Lead)								—		—		—		—		—		—		—		—		Considerable	Some; lateral cracking	Fair	Good	Excellent
200	15	.625	—		—		1	.875	—		—		—		—		1	.250	—		43	.750	32	.250	4	.000	—		1	.250	—		—		—		—		Medium	Bad cracking	Good	Good	Fair

“As before stated, the committee believes that a serious mistake was made on the test fence in painting out the leads and other formulas on the various woods without any special attention to reduction to suit the nature of the wood, thus accounting largely for the difference of the wearing of the paints on the different woods.

“The reduction of the white leads especially was to be criticised in these tests, in many cases too much oil and not sufficient turpentine being present to cause penetration.

“The application of paint to cedar was satisfactory in most all cases, and this wood showed much better results than the other woods upon the fences. The exudation of resinous pitch on the hard pine was extremely serious, in some cases coming through the paint in large streaks, causing bad results.

“It is to be regretted that the house repainting tests which were conducted are of no special value, inasmuch as no information is on file as to the composition of the old paints originally on the houses before the application of the test paints. Imperfections in the old coating, such as excessive chalking, deep checking, scaling, rosin exudations, etc., affected the subsequent coats in such a manner as to prevent any knowledge of where the new and old paint troubles began. The committee, therefore, omitted a detailed inspection of such tests.

“Examination of the three houses which were painted over new wood showed results which correspond with the results obtained from the fence tests. That is, they showed the ultimate value of high type mixtures of several pigments over one pigment alone. These tests seem to indicate that very good results can be secured from most of the paints sold in North Dakota. If the consumer or householder would exercise more care in the selection of wood and preparation of surfaces, with due regard to the proper reduction for various coats, more satisfactory results would be obtained.

“From an examination of certain paints on the 1908 fence containing petroleum spirits, it would appear that this paint thinner is of value, and in the face of conditions such as are presented by the present scarcity of turpentine, the use of petroleum spirits in moderate quantity would be justified.”