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Do I expect too much?

Spent Sunday trying to track down an upper midrange rattle in my system - both channels but not necessarily exactly the same from side to side. I suspected loose or corroded connections but needed to move one of my Monitor Audio Gold 200 floorstanding speakers to access the back of my components. When I did I found a screw on the floor. The screw was only part of the footer and while it needed to be dealt with I don’t believe it was part of the issue. But that did get me to thinking about the speaker screws. These speakers have a unique driver mounting system where they are held in place by screws on the rear of the cabinet that physically pull the drivers into place. I checked them and on both speakers they were all significantly loose - one was about to fall out (my 19-year-old says it’s because I listen too loud but that is whole other string). 
So I looked in my MA manual and it didn’t even mention the screws. Next I went to the MA website and their contact us page allowed me to send an email to their North American distributor - Kevro. I asked for the torque spec. I did receive a prompt reply but was told, “there is no torque specification.  They should be tightened finger tight plus 1/4 turn. 
I expected more - am I wrong?  For one thing I am pretty sure my finger tight and oldhvymec’s finger tight are 2 very different things. For another these screws (maybe they are bolts - it’s a close call) have a broad flat head with a 4 mm hex inset - they aren’t really finger tightable (is that even a word?). 
Also any advice on how to proceed would be appreciated. I recall OHM saying he torqued the hell out of all his speaker screws (or some words to those effect). 
Thanks,

Matt
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asvjerry's avatar
asvjerry
4,606 posts
 
You can always add a Nylock nut to the existing nut, tightened to the same 1/4 turn.  Saves threadlocker (or drips), and isn't permanent.

And mind those bass line forays.... ;)

Nylock nuts ought to be a SOP for woofers, anyway....esp. sealed enclosures.
johnfritter
62 posts
 
I am familiar with your issue, I also received the exact same advice. You may have to use a hex key to turn the bolt to "finger tight". If this is the case use the long side of your hex key. Insert it into the bolt head using your thumb and forefinger to tighten the bolt until the head is snug to the back of the cabinet. By snug I mean just to the point you have full contact between the cabinet and the bolt head. At that point give it the extra 1/4-1/2 turn with your hex key. I say 1/4-1/2 because mine actually took a bit more than 1/4 turn before the bolts would no longer move side to side or up and down. This will make sense when you tighten them up! Hope you find this helpful.
Oh I would also recommend inserting the long end of your hex key in the bolt head when you make the final torque. This way you will have less leverage reducing the chance of accidentally over torqueing the bolt. 

Have a good day!
JF
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feldmen4 OP
115 posts
 
Lots of good advice. I really appreciate all of the thoughtful responses. 
There does seem to be some misunderstanding about how these drivers are mounted. Each driver has a single bolt/screw that secures it from behind. There are no bolts/screws around the rim of the driver - just the one pulling it into position from behind. Thus no torquing pattern is possible. 
I didn’t realize this until I was tightening them on Sunday. Given this single relatively insubstantial screw/bolt per driver getting the torque right seems imperative. The fact that they were as loose as they were is evidence of this need. 
I know how much damage over tightening can do so I don’t want to go there. Give that @erik_squires indicates finger tight would span up to 1/8 turn and the instructions are to only turn it 1/4 turn once finger tight this allows for as much as a 50% difference in bolt/screw stretch depending on judgement. I’ve been involved with the design of mechanical systems for years and understand the difficulties in actually measuring torque accurately, but this much variability seems excessive. 
@johnfritter - it is a little comforting, in a contorted manner, that at least the advice is consistent. 

Matt
johnfritter
62 posts
 
@feldman4 
I do agree A torque spec would be great. I tried and tried to get a torque spec from the only to get re-worded versions of the same reply. Maybe I will try and reach out to the home office and bypass the US. distributor. I have only had trouble with the upper two bolts and after tightening I haven't had any issues since. I do play at what could be considered "excessive" volume on a regular basis. I listen to a wide variety but I'm an old rocker by hart so......!
russ69's avatar
russ69
3,501 posts
 
"... I do agree A torque spec would be great..."

Torque angle is a very accurate way to apply torque settings. This eliminates the differences between a dry fastener and a lubricated fastener or materials that have different surface frictions. They gave the OP the info he needed.
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