How to fit a strap to this?

[Lc130]

This is a Gruen needing a curved spring bar.  The spring bar touches the middle of the case so what type of strap could be fitted?  

Thank you

Charlie

 

[rogart63]

A very flexible one . Had a chronograph that had such a tight fit . A vintage strap in soft suede was the only one i manage to fit. A Nato or perlon would work. 

[spectre6000]

Is there a reason not to get a longer spring bar and curve it further?

[WatchMaker]

You can certainly get more curvy curved spring bars to provide better clearance:

https://www.cousinsuk.com/product/curved-0180mm-8mm-to-26mm-iso-swiss

[Lc130]

13 hours ago, spectre6000 said:

Is there a reason not to get a longer spring bar and curve it further?

Good idea, didn't occur to me.  Is a special tool needed?  Also, I don't see more curved options as WatchMaker mentioned.

[spectre6000]

1 minute ago, Lc130 said:

Good idea, didn't occur to me.  Is a special tool needed?  Also, I don't see more curved options as WatchMaker mentioned.

Yes. I don't know if it's strictly necessary or not (never done it myself), but as an example:

https://www.esslinger.com/spring-bar-bending-pliers-5-inch/