What's with the tubes on my '59 Yuba Greenie??

[jpdalton]

In another thread, I mentioned picking up a Greenie (serial number 362118) to restore over the weekend. I was at a point of mounting the bench tubes on my 10ER-based jig to clean them up, when I saw this...
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Holy variable thickness, Batman! Then I realized that the exceptional thickness didn't extend through the entire tube. And after further examination, it appears that both "bench tubes" were fabricated from [rough] way tubes (the way and bench tubes on this unit have the same OD), with an insert on one end to make up the additional length required of the bench tubes.
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So, the question I'm interested in exploring is: why?? I don't think this was a home-made replacement for factory bench tubes - the quality of the silver paint job was too good for a home project - so if that's true, why did Yuba choose to make bench tubes in this fashion?? Did they have a surplus of rough-finished way tubes, and not enough conventional bench tubes?? Was this an experiment to see if there was a cheaper solution to provide what were typically multiple tube types??

Anyone else ever seen tubes like these??

[chapmanruss]

That is a first for me. I have owned/own only three Greenies, 1956 to 1957 ages.

John, you said,

the way and bench tubes on this unit have the same OD

Could your Greenie S/N 362118 (made in January 1960 according to the records) be near the beginning of the change in the Bench Tube diameter? Does it have the Bench Ends with the smaller diameter Bench Tube openings?

[HopefulSSer]

Hmmm. My Yuba greenie (362819) doesn't have tubes like that. Mine appear to be one piece, not spliced. My tubes are 1.75" diameter. My paint seems similar to yours

[jpdalton]

Does it have the Bench Ends with the smaller diameter Bench Tube openings?

No… the bench end openings are quite a bit larger than the bench tubes.

[jpdalton]

My tubes are 1.75" diameter. My paint seems similar to yours

So are the openings in your bench end castings quite a bit larger than your 1.75” bench tubes? The castings were changed at some point to make those holes smaller (to better fit the then smaller tubes).

[JPG]

Rather than the hole diameter, the side stop is more relevant. They are each 1/16" closer to properly position the 1 3/4 " bench tubes.

[HopefulSSer]

My tubes are 1.75" diameter. My paint seems similar to yours

So are the openings in your bench end castings quite a bit larger than your 1.75” bench tubes? The castings were changed at some point to make those holes smaller (to better fit the then smaller tubes).

I don't think I'd say "quite a bit" larger

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[chapmanruss]

Could it have been from the factory testing the change to the smaller diameter 1-3/4" Bench Tubes. Could it have been a previous owner (who can do a good paint job) that made the change. We may never know. After this many years, changes could have been made to any OEM Mark 5 Greenie or later Mark 5/V. I have seen many examples of that occurring.

The 3 Greenies I have owned/own are from 1956 and 1957 and did not have painted Bench Tubes. Painting the Bench Tubes appears to have been a later in production change for the Greenies. Just for size reference is a picture of the Bench Tube and Bench End juncture of a 1960 Goldie with 1-3/4" Bench Tubes.

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