Re: Pietenpol-List: Re: Ash fuse gear block mounts... Just realized are

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Re: Pietenpol-List: Re: Ash fuse gear block mounts... Just realized are

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Original Posted By: "Dortch, Steven D MAJ MIL USA NGB"
Subject: Re: Pietenpol-List: Re: Ash fuse gear block mounts... Just realized are3/4 not 1&qu UNCLASSIFIED> I'm not sure why it would be 1 tapering to 3/4 anyway. When the plane was designed,1" lumber was indeed 1" thick. Getting 1" thick ash these days would requirelaminating, cutting down from 8 (or maybe 6/4) or more rarely, buying 5/4lumber. It's possible Pietenpol was using what was generally available. Muchof the cross section strength here is coming from that piece being laminatedonto the belly pan piece of 1/4 plywood. I am not sure when the market changed but the "rationale" from the lumber industryis:In the past, you could buy "rough" lumber, wood that actually met the dimensionsbut it was measured green and not planed or shaped, at the lumber yard. Mosthome framing and construction was done with rough lumber.It may not have a straight edge and almost looked "fuzzy" but it was in 1 inchincrementsLumber's nominal dimensions are given in terms of green (not dried), rough (unfinished)dimensions. The finished size is smaller, as a result of drying (whichshrinks the wood), and planing to smooth the wood. However, the difference between"nominal" and "finished" lumber size can vary. Now you get "finished" lumber that has been planed and shaped. BUT it is smallerin all dimensions than rough lumber. You can order lumber in the bigger dimensionsbut it is just about as cheap to buy a larger size and rip it down. My experience in this area is in working with historic homes. We often had to ripbigger wood down to a full specification. The best thing was to be able tosalvage wood from a period home that was being destroyed. Blue Skies,Steve DJust found this on Wikipedia (so it must be true):Early standards called for green rough lumber to be of full nominal dimension whendry. However, the dimensions have diminished over time. In 1910, a typicalfinished 1-inch- (25mm) board was 1316in (21mm). In 1928, that was reduced by4%, and yet again by 4% in 1956. In 1961, at a meeting in Scottsdale, Arizona,the Committee on Grade Simplification and Standardization agreed to what isnow the current U.S. standard: in part, the dressed size of a 1inch (nominal)board was fixed at 34inch; while the dressed size of 2inch (nominal) lumber wasreduced from 1 58inch to the current 1 12inch.UNCLASSIFIED________________________________________________________________________________
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