I have the micrometer but not a chrome SOM. Aluminum Set-O-Matic was used almost two full years, '68 to late '69. Was not aware they are not compatible, good info.

I had no idea myself, otherwise I would have asked if he had the Aluminum or Chrome tom post. I can't offer a refund, but I do want to help rectify the situation for the gentleman who purchased the mounts from me. I certainly don't wanna say it's out of my hands, though it is. Because I feel then I'd come off rude or non caring.

But - at least we all now know the slight variation, so that is a good piece of information.

Measurements.... In the same order as Glenn's...

equal 0.557 and 0.655 Inch (not a huge difference just enough)..

Note.. a few years ago I purchased (from someone on here) a pair of the Chrome tom mounts... Whilst they looked in mint condition, when installing them I noticed that on both mounts.. The two raised "rails" that are cast inside the female section of the mounts had been filed away. Whilst not important to me as they still hold well, it seemed that this would be the easiest possible way to mod those mounts to take a larger post... EG;

Vice+Roundfile+about 10 minutes...

Cheers

John

Thank you Mark!

John, great info thanks for helping out on this one.

Now we know. :)

John,

Yes, doing some filing may get things back in order. This whole ordeal can be a valuable learning experience for all of us!

-Mark

Thank you guys for the info on all this.

John - which part in the photo are you referring to? Here is the bass & two tom mounts. I informed the buyer of all this shared info with regard to different sizes,year,etc...

Jay... have used your pic to illustrate... the what I called "rails" are on each of the chromed mounts. The ones I purchased were for toms , and the rails had been totally filed away.. Slightly enlarges the mount and may sort out your mismatch..

Cheers

John

John, thank you!

Hey guys!

Just checked my original 1968 aluminum tom and bass drum mounts. No "rails" on these parts. That accounts for the difference of why the majority of earlier posts will not go into the chromed version. File those down and there should be no issues....hopefully!

-Mark

Cool Mark... sound's promising..

Cheers

John