Tube diameter in A-3 switcher 3/4" scale

[kwoodhands]

I have been working on the A-3 Switcher for a couple of years now. I am working on the boiler and found a problem I can't figure out.
The tube dimensions as shown on page 133 ,fig 23-1 of the boiler assembly is stated, .787od. x. 047, 9-5/64".I understand the length and wall thickness but not the .787 diameter.The tube bores are .752 as shown on pg 137 fig 23-11. This makes sense as 5/8" copper pipe is .750 x .049.
Is the .787 a misprint or mistake or am I missing something obvious.
mike

[grege]

I assumed this was a discrepancy, and given the choice between .750" OD or the next size up being .875", I used the smaller.

Also, this was a case where the 'is it metric?' game comes in.
The .787" is 20mm.

Greg

[kwoodhands]

Thanks Greg, I just wanted to be sure I wasn't missing something that was obvious.I am finally getting to the point where I machine a part only once. I didn't want to practice on copper, gets expensive.
So far I only found a very few things that appeared to be typos rather than mistakes.
I will read the posts from mistakes, changes and erratica when I get more time.Might be helpful to ward off any major errors.
mike