ALTEC - Screw size ?

[thomasdf]

Hello

I am using a salvaged Altec 1606 rack enclosure to build a hinged front panel varimu compressor. The problem is I am located in Europe (France) and I cannot figure out what are the four locking screws dimensions. Easier to figure out a male screw than a female tap ...
Looks like it's around 3.9mm but that doesn't match with either a no6 or no8 screw...

Can anybody help me with this ?

I would love to find some thumbscrew for these.

Thanks a lot in advance

Thomas

edit : chatgpt tells me it may be a #7-32 UNC ?

 

[emrr]

It's rare to fined odd numbered imperial screws in the US. I've come across some #5, which is also what's specified by Switchcraft for XLR panels. They are special order pretty much everywhere.

Offhand I think those are #6 or #8, same screw on many other Altec pieces, and I've replaced them with other even numbered imperials....whichever they are!

 

[thomasdf]

Thanks Doug ! #8 seems to be 4.17mm, which def seems too big, as I can manage to screw in a M4 (4mm) a certain amount of turns only.
#6 seems to little (3.51mm) but I should def give it a try !

Another solution might be drilling & tapping for european screw ... but if I screw up (hmm..) the enclosure is shot

 

[OneRoomStudio]

You probably already know this, but just in case - Imperial screws come in different pitches too. #6 comes in “fine,” (6-40, or 40 threads-per-inch), and “course,” (6-32, or 32 threads-per-inch).

Those look like they could be 6-32 screws to me.,

 

[emrr]

You probably already know this, but just in case - Imperial screws come in different pitches too. #6 comes in “fine,” (6-40, or 40 threads-per-inch), and “course,” (6-32, or 32 threads-per-inch).

Yep, though rarer to see the fine pitch versions. Usually!

 

[zzzzz]

Presumably 6-32, only saying that because I just replaced some stripped screws in a 1567a last week

 

[heatwalk]

oh dear. I misplaced those screws on a 1592 and remember thinking it was hard finding the correct match which makes me think a if they are a weird in between 7-32 might make sense? I think 6 felt like there was wiggle room