2307, 2311, 2312 Bolt Pattern

[Mr. Widget]

I need to know the mounting hole dimensions for the JBL 4.25" diameter exponential horns. (Baffle end) I was able to track down the cutout and flange diameters, but I still need the center to center distance for the mounting bolts.

Thanks,

Widget

[Hofmannhp]

Originally posted by Mr. Widget
I need to know the mounting hole dimensions for the JBL 4.25" diameter exponential horns. (Baffle end) I was able to track down the cutout and flange diameters, but I still need the center to center distance for the mounting bolts.

Thanks,

Widget

Hi Widget,

if you are able to wait till this evening (germany - 9h), your time 9:00 AM, I will figure it out.

BTW: I just think about to make a model for casting a horn like the 2307/12 with 1.5" throat (a shortend version of the 2312) . A friend of mine is able to do the casting in aluminium (don't know the cost at this time)

HP

[subwoof]

well onethat are sitting on my computer say 5.415 inches....?

I am eyballing a worn pair of re-tapped holes though and they seem to differ...

I have a NOS 2307 I can measure in a few hours.....

sub

[Tom Loizeaux]

I just measured the spacing asked by Widget on one of my 4333s. It measures 137.75mm. It looks to be 96.3mm from one machine screw to the one closest to it (ie: 3 o'clock to 6 o'clock, etc.).
Hope this helps.

Tom

[Hofmannhp]

ok gentlemen,

with this we find out what the fabrication tolerances from JBL are:thmbsup:

HP

[Hofmannhp]

Originally posted by Hofmannhp
ok gentlemen,

with this we find out what the fabrication tolerances from JBL are:thmbsup:

HP

I measured my 4333B and got 138mm bolt circle diameter.

but then I found the original JBL mounting template.....137mm.

mathematical correct is 137.31875mm, ....they rounded the mm, I believe the inches are right.
HP

[Mr. Widget]

I appreciate all the help.

Widget

[subwoof]

Well that's a nice even measurement...kinda like the 13 31/32 for the 15" cutouts.

easy to see with sawdust-encrusted shop glasses......

:cheers:

sub