The only problem with having a removable header tank, or any other removable part on our planes is this...

If the part is removed for any length of time, you may find that upon reinstallation, it has changed its shape slightly.
Not a big deal if you are screwing parts back together. My header tank had a perfect fit and still does, but immediately after construction of the forward deck/header tank, the hinge pins slid in and out with ease, now they are quite stiff. No, don't ask me how many years my completed header tank sat on the shelf!  :-)

I think that if I were to do it all again, I might use screws instead of hinge.
There are no good arguments for permanently bonding the header tank, only bad ones IMHO.

Angier Ames
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