Fastening smaller drivers

Cheap wrench and/or cheap screws/bolts, i.e. poor fit in various ways combined with using power drills and worse, folks that believe they have calibrated elbows, wrists, etc. for what are normally little more than finger tight torque requirements IME
 
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Brass Robertson screws.

dave
 
Yeah I noticed that in the US (I have family in the US).

Here it's basically the same price, or such a little difference that you just can't be bothered.

I don't understand how you could slip a torx or allen head?
Unless you start screwing before your bit is already in maybe?
The problem I'm talking about with torx head screws is when your drive bit wears out and decides to jump teeth. It happens much faster and without warning to torx, square drive and allen bits than with philips. You can usually save a philips head screw and still remove it if the bit wears out and jumps a few times, but not so much with the others.

All things considered, if the drive bits are new as well as using good quality screws which fit well, I'd rather use torx and allen heads. If the bit isn't of highest possible quality, then you run a high risk of stripping the head in just one shot. Then you're really "screwed".
 
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Glad you like my ghetto solution lol.
This principle comes from the constant need of modifications as I am never happy with anything and want to change drivers and combinations and what not constantly.
If I get sick of the horn I can make a new baffle and swap it to a normal midrange or just make it two way.
If I want a new bass hopefully the cutout and the bolts fit, if not I can adjust without having to start all over with a new cab. Also double baffles serves well as a resonator killer.
Maintainability, flexibility, upgradability and modificability are key to me.


I will tell you that I get into the same place as you, needing different drivers with different diameters and holes, etc. Thing is, I got all fancy once and decided to make an adapter ring out of brass. I used a circle jig and a router. It worked, but I will never do it again with those tools! I have also used Corian for this and I think that it is worse than MDF (somehow) with dust and smell. Yikes. Those are two things that I outside. If you can get something that is versatile in the end, that's cool.

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@planet10 While I appreciate your creations and admire the attention to detail, funny thing is, I don't like to see bright colored screw heads on black surfaces. It drives me crazy. Sort of looks cheapened to me.
I'm guessing that you wouldn't appreciate some of the Harbeth speakers, some have LOADS of bright galvanised screw heads strewn across the front (dark) baffle, why? They'd look so much better with black screws. I think with oak you should use brass because of the acid in the wood, but there's not many oak front baffles.
 
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Yeah, Harbeth is a thorn in my eye. I've owned 2 pairs of them. Loved the sound and the way they convey acoustic space, natural tonal balance and how they integrate into a room. Playing a vocal or instrument solo is shockingly real, like the performer is in your room. No other speaker can do this the way Harbeths do.

Now that being said, i hated their look. I actually painted all the screw heads black, in a way it could be reversed upon resale.

I miss these speakers alot, especially their midrange quality. Just hate the way they look.
 
It seems that when Visaton say '3.9mm hole and 7.2mm recess' they mean 'yep - too small for M4'. Just.
And the choice of M3.5 is not what it could be.
I guess I'll have to try with M3 - not a lot of choice there either, but at least there is some.😕
 
I have press-fitted small drivers with butyl caulk (sold in bricks and sometimes strips/rope for electrical and air duct sealing)
eventually it will harden but not be a permanent bond. it helps to seal the wood baffle with varnish, paint or glue to make a non-porous surface for stickiness.
 
Could you not just drill them slightly larger? It's only 0.1mm.
Given my equipment and skills, I don't really feel like butchering £170 of drivers when there are alternatives.
It is tempting to throw in the towel and just install a tweeter, but that just procrastinates on these drivers, which seem to have a good reputation.
In theory I do have all the parts from my eBay purchase for the RS225/B80 FAST, and I feel I should follow through.
 
I did try with a bolt I had from the usual Monacor bolt/t-nut combos that are widely sold here, but it was tight - and the neck near the head isn't happy.
There's no sense stressing it - its not as if these things are expensive or have a short shelf-life.
I do wish there was a bit more standardisation especially with tweeters - while M4 seems common, the radius that the holes need to be on is not quite so much, even when they have 4 bolts.
 
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I am reading things that remind me of engineering school.
I equate it to building a swing set with a 2 cu. mtr foundation on each of the legs to make sure that when T-Rex wants to come to the party, you will be ready.
Gentlemen, this is a 4" driver that he may want to remove 15 or 20 times.
More than that and I have spelled out how easy it is way back in this thread.
Threaded inserts. Seriously? I know you are trying to help but...
Sometimes more is not better. It is unnecessary and wasteful in time, money and energy spent.
 
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I don't see or understand what's wrong with talking and discussing about some nice possibilities to give a speaker even a nicer finish?
Threaded inserts are not difficult, nor expensive either?
Some people also just really like over engineering things, nothing wrong with that either 🙂

I actually picked up a few new ideas, maybe not totally related to speaker building, but they might becoming very handy in some other projects! 🙂
So I always enjoy reading about these kind of things!

Also, unless you just want to screw something in just one or two times, with MDF I wouldn't advice screwing things in directly.
Even more so with small drivers, because the amount of "meat" around the screw holes is so thin.
I have only bad experience with that.