[Illustration: Typical Sample of Hard Pine Trim Board Showing Knot and Sappy Grain]
[Illustration: Test No. 13--1906 Fence
Complete Disintegration and Failure of Cheap Paint]
"Non-absorbent woods, difficult to penetrate, such as those on the west side of the fences, would undoubtedly have given much better results had they been painted with paints properly reduced to suit the nature of the wood. This treatment seems to have been overlooked in the North Dakota tests, and the painting of the hard pine boards was done with the same consistency of mixtures and the same reductions as upon soft pine.
Scaling of course resulted. One of the chief purposes of the fences, however, was to study the different types of wood, and compliance with this desire resulted in the bad conditions herein noted. It has been shown in many other field tests that adherence of paints to hard wood surfaces can be obtained only by causing the priming coat to become amalgamated with the woody fibre, by the use of a large percentage of volatile diluent turpentine, benzole, asphaltum spirits, etc., to secure penetration. If such treatment is omitted, failure soon results, as was evidenced by the uniformly bad conditions presented by the paints on the hard pine panels.
[Illustration: Pine Weatherboarding Showing Knots and Grain]
[Illustration: Condition of Lumber Affecting Paint, West Side 1906 Fence]
[Illustration: Hail-stone Abrasions on House Repainting Tests]
[Illustration: Hail-stone Effect, West Side of 1907 Test Fence]
"During July, 1908, a violent hailstorm occurred in Fargo, and left its impression on nearly every wooden structure; in many cases deep dents being made into the wood. The west side of the test fences, which received the most injury from this storm, was covered with these dents over almost its entire surface, causing cracks in the form of concentric rings to appear on the abraded paint coatings. The bad condition of the wood, improper method of applying priming coat, combined with the hailstorm effect on the painted surfaces on the west side of the fences, were undoubtedly responsible for the universal failure of the paints thereon, and, for these reasons, the west side was eliminated from the detailed inspection, only general observations of these tests being made. These general observations, however, showed that paints Nos. 6 and 8 on the 1906 fence, and paints Nos. 8, 10, and 13 on the 1907 fence, proved the most satisfactory on the western exposure.[29]
[29] These formulas were the same as those respectively numbered on the Atlantic City and Pittsburg fences.
[Illustration: Peculiar Crystallization Effect on Section 41. New Special Fence Paint Applied During Cold Weather]
"Ochre was tried out as a priming coat on several formulas, but it was found to be most unsatisfactory, affecting the subsequent coats of paint and causing early failure, as evidenced by broad checking, discoloration, and general bad condition. These conditions also apply to those panels on the 1908 fence coated with shellac as a primer.
"The colored formulas in every case showed a great superiority over the same paints in white untinted, and demonstrated that a percentage of color has a wonderful influence on the preservation of the paint coating, reducing chalking, checking, and general disintegration. This condition is probably due to the reinforcing value of the color pigments used.
"It is safe to state that the combination formulas tinted yellow were of better appearance than the corroded white leads tinted yellow, the latter appearing quite dark in many cases.
"The wearing of the paints made solely from white lead and zinc oxide seemed to indicate that a percentage of a third pigment, of an inert nature, would have been beneficial.
"The high-type mixtures of pigments containing lead and zinc, with moderate percentages of inert pigments, on good wood, were in most excellent general condition; in fact, much superior to the single pigment paints. Their surface exhibited only minor checking and moderate chalking with good maintenance of color, and presenting surfaces well adapted to repainting.
"The sublimed white lead was in fair condition, with very little checking, and offering a fair repainting surface. The corroded white lead was somewhat whiter than the sublimed white lead, but a careful observation of the surface of the corroded lead revealed deep checking.
"It was clearly demonstrated, however, that in climates of the North Dakota type, white lead alone is not entirely satisfactory. The addition of zinc oxide to white lead forms paint that has proved much superior to the white lead alone.
"It was conclusively demonstrated that mixtures of white lead and zinc oxide, properly blended with moderate percentages of reinforcing pigments, such as asbestine, barytes, silica and calcium carbonate, are most satisfactory from every standpoint, and are superior to mixtures of prime white pigments not reinforced with inert pigments.
"The white leads painted out on the 1908 fence exhibited different degrees of checking, the mild-process lead and sublimed white lead which presented the best surfaces, being free from checking, while the old-process leads seemed to show very deep and marked checking, even after one year's wear.
[Illustration: Corroded White Lead
Sublimed White Lead
Condition of Two White Leads on Two Grades of Wood]
[Illustration: Photomicrographic Apparatus and Method of Use]
CONDENSED REPORT OF INSPECTION OF "1906" TEST FENCE
FARGO, N. D., NOV. 19-23, 1909
_No gloss shown by any of the paints. Formulas in white on white pine only included here, on east side of fence_
==+=========================================================================++ T FORMULAS e+--------------------------------------------+----------------------------++ s PIGMENT VEHICLE t+--------------------------------------------+----------------------------++ Corroded Linseed Oil N White Lead Turp. and Drier o Sublimed Japan Drier . White Lead Water Zinc Oxide Benzine Calcium Drier Carbonate Vola- Silica and tile Silicates Oil Barium Sulphate Magnesium Silicate Clay and Silica Bary- tes and Sili- cate --+-----+-----+----+----+---+----+---+---+-----+----+----+--+----+----+-----++ % % % % % % % % % % % % % % % 1 100 -- -- -- -- -- -- -- -- -- -- -- -- -- -- 2 -- 100 -- -- -- -- -- -- -- -- -- -- -- -- -- 3 50 -- 50 -- -- -- -- -- -- 90 10 -- -- -- -- 4 -- 60 40 -- -- -- -- -- -- 90 -- 10 -- -- -- 5 28.7 -- 71.3 -- -- -- -- -- -- 93 7 -- -- -- -- 6 40.2 -- 50.3 4.1 5.4 -- -- -- -- 90.7 9.3 -- -- -- -- 7 21.9 21.9 45.8 10.4 -- -- -- -- -- 89.6 9.7 -- 0.7 -- -- 8 44.1 -- 46.0 4.6 -- -- 5.3 -- -- 86.0 12.6 -- 1.4 -- -- 9 In gray only No report. 10 13.9 -- 34.9 26.8 -- -- -- -- 24.4 72.2 -- -- 24.0 3.8 -- 11 55.0 -- 15.2 -- -- -- -- -- 29.8 Test not finished 12 -- 5.1 25.0 -- -- -- -- -- 69.9 -- -- -- -- -- -- 13 -- -- 31.3 45.4 -- 22.8 -- 0.5 -- 57.2 -- -- 16.1 26.7 -- 14 34.8 5.4 59.2 -- -- -- -- -- -- 86.0 13.7 -- 0.3 -- -- 15 -- -- 64 -- -- 36 -- -- -- 98 -- -- -- -- 2 ==+=====+=====+====+====+===+====+===+===+=====+====+====+==+====+====+=====++
==+============================================== REPORT OF CONDITION +--------+-----------+-------+-------+--------- T e s t N CONDITION o CHALKING CHECKING HIDING COLOR FOR RE- . POWER PAINTING --+--------+-----------+-------+-------+--------- 1 Very bad Extremely Good Good Only fair deep 2 Bad Very slight Good Light Fair yellow- ish tint 3 Medium Fine matt-- Good Fair Fair to deep in good places 4 Medium Surface Good Good Fair checking, very slight 5 Slight Quite deep Medium Good Poor.
Coating wrinkled and hard 6 Medium Slight Good Good Good surface checking 7 Medium Surface Fair Good Slight checking shelling with slight from wood cracking 8 Medium Very slight Good Good Good 9 10 Slight Very bad Bad condition throughout.
11 12 Medium Medium Defici- Good Shelling ent from wood 13 Worst looking surface in North Dakota tests.
14 Medium Slight Fair Good Good surface checking and peeling 15 Slight Lateral Good Good Hard film cracking quite deep ==+========+===========+=======+=======+=========
CONDENSED REPORT OF INSPECTION OF "1907" TEST FENCE
FARGO, NORTH DAKOTA, NOV. 19-23, 1909
===+========================================================================== T FORMULAS e +-------------------------------------------+------------------------------ s PIGMENT VEHICLE t +-------------------------------------------+------------------------------ Corroded White Lead Linseed Oil N Sublimed White Lead Turpentine o Zinc Oxide Drier . Calcium Carbonate Turpentine Aluminum and and Magnesium Silicate Japan Barytes Water Silica Turpentine Inert and Benzine Magnesium Japan Drier Silicate Drier Calcium Vola- Sul- tile phate Oil Zinc [B]
Lead ---+----+---+----+---+--+--+----+--+---+--+----+----+----+--+----+--+--+--+--- 1 30 -- 70 -- -- -- -- -- -- -- -- 93 7 -- -- -- -- -- -- 2 50 -- 50 -- -- -- -- -- -- -- -- 86 -- 10 4 -- -- -- -- 3 20 20 50 10 -- -- -- -- -- -- -- 90 -- -- -- 10 -- -- -- 4 48.5 -- 48.5 3 -- -- -- -- -- -- -- 83 -- -- -- 17 -- -- -- 5 22 -- 50 2 26 -- -- -- -- -- -- 90 -- -- -- -- 10 -- -- 6 -- -- 64 -- -- 36 -- -- -- -- -- 98 -- -- -- -- -- 2 -- 7 37 -- 63 -- -- -- -- -- -- -- -- 85 13 -- 2 -- -- -- -- 8 38 -- 48 -- -- -- 14 -- -- -- -- 91 9 -- -- -- -- -- -- 9 -- -- 73 2 -- -- 25 -- -- -- -- 66 -- -- 12 22 -- -- -- 10 44 -- 46 5 -- -- -- -- -- -- -- 86.0 12.5 -- 1.5 -- -- -- -- 11 50 -- 50 -- -- -- -- -- 5 -- -- 78 22 -- -- -- -- -- -- 12 60 -- 34 -- -- -- -- 6 -- -- -- 91 7 -- 2 -- -- -- -- 13 -- 60 27 3 -- -- -- -- 10 -- -- 90 -- -- -- -- 10 -- -- 14 25 20 25 5 -- -- -- -- -- 25 -- 90 -- 6 -- -- -- -- 4 15 -- 20 40 10 -- -- -- -- -- -- 30 90 -- 8 2 -- -- -- -- 16 33 -- 33 -- -- 34 -- -- -- -- -- 90 -- 10 -- -- -- -- -- 17 100 (Type A) -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 18 100 ( " B) -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 19 100 ( " C) -- -- -- -- -- -- -- -- 10 gal. oil -- -- -- -- reduction 20 -- 100 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 21 -- -- 100 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 22 -- -- -- -- -- -- -- -- -- -- 100 -- -- -- -- -- -- -- -- 23 100 (Type C) -- -- -- -- -- -- -- -- 5-1/2 gal. oil reduction for priming 24 37. 7. 25. 20. -- -- 8.42 (Michigan Seal -- -- -- -- -- -- -- 51 84 87 36 White Lead) 25 38. 4. 33. 19. -- -- 3.18 (Railway White -- -- -- -- -- -- -- -- 95 81 58 48 Lead) 200 15. -- -- 1. -- -- -- -- 1. -- 43. 32. 4. -- 1. -- -- -- -- 625 875 250 750 250 000 250 ===+====+===+====+===+==+==+====+==+===+==+===+====+=====+==+====+==+==+==+===
[B] = Benzine
===+=========+========================================= T REPORT OF CONDITION e +------------+------+------+-------------- s t N o . CHALKING CHECKING HIDING COLOR CONDITION FOR POWER REPAINTING ---+---------+------------+------+------+-------------- 1 Medium Considerable Fair Fair Poor surface; with lateral too hard cracking 2 Medium Considerable Good Fair Rather poor with lateral cracking 3 Bad Medium-- Good Good Fair scaling some 4 Medium Considerable Good Good Medium with lateral cracking 5 Slight Slight Good Good Good 6 Medium Considerable Medium Medium Fair 7 Consider- Present; Fair Fair Poor able long cracks 8 Slight Surface Good Good Fair checking 9 Not Considerable Medium Good Medium evident with lateral cracking 10 Medium Very slight Good Good Good 11 Slight Lateral Fair Fair Fair cracking 12 Consider- Present with Fair Fair Not very good able slight cracking and scaling 13 Medium Surface Good Good Good checking only 14 Consider- Considerable Medium Fair Medium; some able with lateral washing shown cracking 15 Medium Medium Good Good Medium 16 Medium Slight; some Fair Good Medium shelling 17 Bad Alligator- Good Fair Poor ing; deep checking 18 Bad Alligator- Fair Fair Poor ing; deep checking 19 Bad Deep Good Fair Poor 20 Consider- Slight Good Fair Fair able 21 Not Consider- Fair Good Poor evident able; slight cracking; scaling 22 Medium Lateral Good Good Fair cracking; split 23 Bad Medium deep Good Good Fair 24 Consider- Slight; Fair Good Good able lateral cracking 25 Consider- Some; Fair Good Excellent able lateral cracking 200 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."
NORTH DAKOTA TESTS
[Illustration: 1. Formula No. 21, Section 31, on 1907 Fence]
[Illustration: 2. Section 80, on 1908 Fence]
[Illustration: 3. Formula No. 6, Section 9, on 1907 Fence]
[Illustration: 4. Formula No. 2, Section 3, on 1907 Fence]
[Illustration: 5. Formula No. 1, Section 1, on 1907 Fence]
[Illustration: 6. Formula No. 14, Section 21, on 1907 Fence]