Ask the Scholar

Page 15 of 54
I can add historical knowledge about this page.

Page image

Page 15

OCR

HARTNESS S CREW THREAD COMPARATOR Fig. 16. Sketch shows bad lead error in a screw having the smallest allowable pitch diameter. This screw would be barely acceptable if it had a true lead. The foregoing sketches have been used for illus- tration because they are free from the surface irregu- larity found in the photos of work. It simplifies our approach to the problem if we see the effect of the shifting of the shadow on the tolerance chart under the effect of variation in diam- eter and lead. The reciprocal effect of lead and diameter is shown at a glance. 28

Document source description

This is a publication about a comparator machine for the inspection of screw threads, with illustrations by Russell W. Porter.

Page data

Page
15
Source index
0
Type
photo
Media ID
76ace861daadf7bc
Size
unknown

Document data

ID
7077469
Core
doc
Type
document
DTO data
{
    "id": "7077469",
    "sourceUrl": "https://catalog.archives.gov/id/7077469",
    "contentType": "document",
    "title": "Hartness Screw Thread Comparator for Accurate and Rapid Screw Gaging",
    "description": "This is a publication about a comparator machine for the inspection of screw threads, with illustrations by Russell W. Porter.",
    "citationUrl": "https://catalog.archives.gov/id/7077469",
    "collections": [
        "Russell W. Porter Papers",
        "Publications"
    ],
    "iiifBase": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "thumbnailUrl": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "largeImageUrl": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "imageCount": 54,
    "hasImages": true,
    "source": "import",
    "hasTranscription": false
}

Context sent to Scholar

Document identity
{
    "localId": "7077469",
    "label": "Hartness Screw Thread Comparator for Accurate and Rapid Screw Gaging",
    "core": "doc",
    "dtoType": "document",
    "citationUrl": "https://catalog.archives.gov/id/7077469"
}
Document source metadata
{
    "id": "7077469",
    "sourceUrl": "https://catalog.archives.gov/id/7077469",
    "contentType": "document",
    "title": "Hartness Screw Thread Comparator for Accurate and Rapid Screw Gaging",
    "description": "This is a publication about a comparator machine for the inspection of screw threads, with illustrations by Russell W. Porter.",
    "citationUrl": "https://catalog.archives.gov/id/7077469",
    "collections": [
        "Russell W. Porter Papers",
        "Publications"
    ],
    "iiifBase": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "thumbnailUrl": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "largeImageUrl": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-002-pr.jpg",
    "imageCount": 54,
    "hasImages": true,
    "source": "import",
    "hasTranscription": false
}
Document source extras
{
    "url": "https://catalog.archives.gov/id/7077469",
    "naId": 7077469,
    "levelOfDescription": "item",
    "productionDates": [
        {
            "logicalDate": "1941-01-01",
            "year": 1941
        }
    ],
    "recordType": "description",
    "ocrSource": "nara-archive"
}
Page context
{
    "seq": 15,
    "pageIndex": 0,
    "type": "photo",
    "url": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/69/774/7077469/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196221-2012-031-pr.jpg",
    "mediaId": "76ace861daadf7bc",
    "ocrText": "HARTNESS S CREW THREAD COMPARATOR\nFig. 16. Sketch shows bad lead error in a screw having the\nsmallest allowable pitch diameter. This screw would be barely\nacceptable if it had a true lead.\nThe foregoing sketches have been used for illus-\ntration because they are free from the surface irregu-\nlarity found in the photos of work.\nIt simplifies our approach to the problem if we\nsee the effect of the shifting of the shadow on the\ntolerance chart under the effect of variation in diam-\neter and lead.\nThe reciprocal effect of lead and diameter is shown\nat a glance.\n28"
}