Yes you can reglue it but it's a little tricky. I would use epoxy and a vice. Remember you have to have the magnet with opposing polarity so it's likely to be a two person job. If the magnet came off it probably took quite a jolt so you might want to make sure everything else is ok and that the original glue job was a weak link. Also look into surface prep before you attempt to glue.
Hi Paul,
My apologies for this problem. Cal is wrong, there's a quick simple fix.
1 - Use a wire brush to roughen both contact surfaces. You only need to brush for a minute or so. Wipe clean with a soft dry cloth.
2 - Apply a good quality epoxy glue to both surfaces and gently press together. The magnetic tension will do the rest (Don't use a vice as Cal suggests).
This method will make the fix and the driver will perform normally.
Thanks
Mark.
My apologies for this problem. Cal is wrong, there's a quick simple fix.
1 - Use a wire brush to roughen both contact surfaces. You only need to brush for a minute or so. Wipe clean with a soft dry cloth.
2 - Apply a good quality epoxy glue to both surfaces and gently press together. The magnetic tension will do the rest (Don't use a vice as Cal suggests).
This method will make the fix and the driver will perform normally.
Thanks
Mark.
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Hi Cal, no worries,
The Alps have attracting magnet systems so its an easy fix (no vice needed). I am contemplating using no glue on this section, giving the guys the choice of non-sheilding or partial shielding. The potential advantage of the non-shield is a slight increase in SPL as the drive-train electrical damping changes; And there's less mass behind the cone inside the box.
The new batch of Alpair 7's have retaining guide lugs built-in to the back of the frame mount so this method is easily possible. More on this when I announce the latest Alp7 in the next week or so.
I'm already running a prototype unit with this option. I'd need to do more testing on this to make sure other performance factors remain stable.
Cheers
Mark.
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Why is this? The functions of increased flux density and magnetic field suppression seem to require opposed magnetisation?
Hi Paul,
I' happy to say its extremely rare to have a glue failure. I've only had 2 fails like this from total runs of 12,000 drivers (Alp7, EL-70 and 2 X OEM versions) Looking at your pic, the glue is evenly spread. It won't be jolt or knock, you would have noticed severely crushed packaging.
We use a 2 pack bonding system (2 glues mixed and applied by machine). This method is industrial and reliable. I recon there will be very slight contamination (moisture or similar) in the joint, hence why I'd like you to lightly wire brush them. That should do the trick. You won't need much glue, just a thin layer on both surfaces.
Glad to help
Cheers
Mark.
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Hi Badman,
Who told you that? Stray magnetic field suppression is an outcome from either method. More important is the control and distribution of the density inside the coil chamber. Now you can start to guess how I extract linear oscillation.
Cheers
Mark.
Hi Paul,
No problem, it will work fine. I guess the glue's set? When I'm making prototypes, I use a couple of short screwdrivers (or a small piece of wood) wedged into the back of the frame and temporarily taped to hold until set. But I only do this is only when I have the time.
Provided you've got the glue two surfaces nice a flat (wire brush), the metal cap will limit any off-set to within 2-mm.
Cheers
Mark.
No problem, it will work fine. I guess the glue's set? When I'm making prototypes, I use a couple of short screwdrivers (or a small piece of wood) wedged into the back of the frame and temporarily taped to hold until set. But I only do this is only when I have the time.
Provided you've got the glue two surfaces nice a flat (wire brush), the metal cap will limit any off-set to within 2-mm.
Cheers
Mark.
Yes the glue is set; guess its OK now. I wire brushed both surfaces with a dremel (?).
The metal cap did indeed limit the off center thing. I glued it with UHU epoxy; it should be good for 300Kg/cm2.
Now they have to go back in the box till my "build my own CNC mill" project is done; then I can give them the enclosure they deserve.
Thanks again!
Paul
The metal cap did indeed limit the off center thing. I glued it with UHU epoxy; it should be good for 300Kg/cm2.
Now they have to go back in the box till my "build my own CNC mill" project is done; then I can give them the enclosure they deserve.
Thanks again!
Paul
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