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View Full Version : 044 - 044-1 diaphragms



rdgrimes
01-18-2009, 03:09 PM
How does one separate the diaphragm from the magnet? And having done so, how does one correctly replace it?

rdgrimes
01-18-2009, 03:39 PM
Also, on the grill, does anyone know the correct sizing for the o-ring? It looks like 1/16" x 2-7/8 ID.

BMWCCA
01-18-2009, 05:13 PM
Also, on the grill, does anyone know the correct sizing for the o-ring? It looks like 1/16" x 2-7/8 ID.

I don't think it was an O-ring on the original 044s, more like a window screen spline without the splines. I think it came as a single length with open ends. The 035 screen locks are O-rings but none of the 044s I've seen are. Of course the hard part is the color. The JBL parts I have for the 035s are black but are the same length (diameter 3") as the 044 gray "strings". The black 035 O-rings measure about 2mm diameter and the 044 gray strings seem to be a bit thicker, closer to an 1/8". Diameter of the 044 and 035 screens are both about 3" and the gasket doesn't have to stretch, just to force into the groove. The JBL part number for the 035 ring is 62664, if that helps. I haven't tried swapping them but I could if it would help. I've got plenty of spare 044s out of cabinets, and a bag new of 035 O-rings. :)

What I can't seem to lay my hands on is my tiny caliper. I believe I took it over to a neighbors to measure the seals in his clutch master cylinder on an antique BMW. :(

JeffW
01-18-2009, 09:17 PM
Whatever rubber parts were on the mesh of my 044(ti) disintegrated, but the magnet is strong enough to hold them in place with no rubber parts. I stick stick them in the groove and they stay put.

rdgrimes
01-18-2009, 09:41 PM
Whatever rubber parts were on the mesh of my 044(ti) disintegrated, but the magnet is strong enough to hold them in place with no rubber parts. I stick stick them in the groove and they stay put.
Also a perfectly good approach. The stuff that came out of this one (in small bits) was black, 1/16" in diameter (0.070) and the groove is 2-7/8" (2.864) inner diameter. There are o-rings available with those dimensions in a variety of materials. But any 1/16" o-ring could be cut and used as long as it was long enough.

So how does one separate the diaphragm? I want to push out some small dents but the thing won't come off the magnet.

grumpy
01-18-2009, 09:57 PM
... assuming you've disassembled the tweeter to the point where there's
a fiber-board carrying the dome (and coil), and leads in view... this has
to be separated from the magnet assembly to see the back side of the
dome (I'm assuming this is the same view as a silver 044). Frankly, I
wouldn't recommend trying this as it can be difficult if the adhesive
is well ... adhered. Others here have tried this and have found it to be
less of an issue. There should be a foam cylinder behind the dome,
likely glued to the magnet assembly, which should be put back in place
(or left alone if still glued).

Good luck, if you decide to forge on.

BMWCCA
01-18-2009, 11:05 PM
I haven't gone as deeply as to remove the diaphragm, but some here have said it either comes right off easily or, as Grumpy implies, it's stuck.

But to the O-ring: I have every reason to believe it's the same one as the 035Ti/TiA/052Ti which is JBL Pro part #62664 RETAINER SCREEN. Retail price of a whopping $0.36. Find whatever you want that works but I just had JBL send me a bag of eight, which now happens to be just the number of 035/052 tweeters I now have in use. I can't confirm that part number for the 044Ti since the exploded diagram for the 240Ti doesn't identify that part. The original gray retainer for the 044, part #60752, seems rather indestructible by comparison and is not listed as available.

SMKSoundPro
01-19-2009, 12:25 AM
Slide a thin putty knife or some other such blade GENTLY between the fiber board diaphragm assembly and the magnet top plate. The fiber board has adhesive on it much like clear packing tape. Just lift the phragms gently and the bond will release.

Be super careful how far in you probe with the knife blade as you risk hitting the tiny voice coil.

rdgrimes
01-19-2009, 07:03 AM
That's about what I figured was needed, but I don't want to damage the coil. Since the diaphragm is near-junk anyhow, I may just swap in a 044 magnet-phragm assembly anyhow. I can live with it not being gold colored till another 044-1 comes along.

BMWCCA
01-19-2009, 07:28 AM
That's about what I figured was needed, but I don't want to damage the coil. Since the diaphragm is near-junk anyhow, I may just swap in a 044 magnet-phragm assembly anyhow. I can live with it not being gold colored till another 044-1 comes along.
Or you could just re- "vapor deposit" the coating this time using Gold Krylon instead of their Dull Aluminum. I might be tempted to try Krylon Premium Metallic "Gold Foil" spray paint. ;)

SMKSoundPro
01-19-2009, 02:24 PM
I might be tempted to try Krylon Premium Metallic "Gold Foil" spray paint. ;)

Me too.

rdgrimes
01-19-2009, 03:25 PM
Slide a thin putty knife or some other such blade GENTLY between the fiber board diaphragm assembly and the magnet top plate. The fiber board has adhesive on it much like clear packing tape. Just lift the phragms gently and the bond will release.

Be super careful how far in you probe with the knife blade as you risk hitting the tiny voice coil.
Ah, well, I found out how far you can safely insert a blade without shearing off the voice coil. :banghead: Oh well, it was a learning experience. It was FUBAR anyhow. Damn thing popped loose and the blade went clean through. This was a good tweet for me to learn on.

Did you know you can see daylight through these diaphragms? There's really not very much metal on them at all.

I'm pretty sure that painting one is not in my future, but thanks for the suggestion. I'll just use an 044 until the right replacement comes along.

SMKSoundPro
01-19-2009, 03:39 PM
The key term was Gently.

There is NOT much aluminum there at all. I still think Krylon!

rdgrimes
01-19-2009, 04:26 PM
The key term was Gently.
Ya think? It was really stuck on there, and then it wasn't. :o:

JSF13
01-19-2009, 04:38 PM
Ya think? It was really stuck on there, and then it wasn't. :o:


LOL,sounds like one of my adventures.;)

grumpy
01-19-2009, 04:57 PM
This was a good tweet for me to learn on.
there ya go.


There's really not very much metal on them at all.
yep, that was pretty much the point. :)

If you can read continuity by putting an ohmmeter on two parts of the dome,
(or surround on the fiber board) it was metal... if not, paint. I have examples
of both. Easy to tell if they're both in front of you to compare.

rdgrimes
01-20-2009, 09:45 AM
I don't think it was an O-ring on the original 044s, more like a window screen spline without the splines. I think it came as a single length with open ends. The 035 screen locks are O-rings but none of the 044s I've seen are. Of course the hard part is the color. The JBL parts I have for the 035s are black but are the same length (diameter 3") as the 044 gray "strings". The black 035 O-rings measure about 2mm diameter and the 044 gray strings seem to be a bit thicker, closer to an 1/8". Diameter of the 044 and 035 screens are both about 3" and the gasket doesn't have to stretch, just to force into the groove. The JBL part number for the 035 ring is 62664, if that helps. I haven't tried swapping them but I could if it would help. I've got plenty of spare 044s out of cabinets, and a bag new of 035 O-rings. :)

What I can't seem to lay my hands on is my tiny caliper. I believe I took it over to a neighbors to measure the seals in his clutch master cylinder on an antique BMW. :(
I got the last 4 of these that JBL-Pro had in stock. He said there were another 900 or so in the warehouse. I'm getting them for free. :)

BMWCCA
01-20-2009, 10:22 AM
I got the last 4 of these that JBL-Pro had in stock. He said there were another 900 or so in the warehouse. I'm getting them for free. :)What? They give you guys a west-coast discount? Damn! And to think I had to pay 36¢-each for them! I hope they charge you shipping. ;)






Or did you mean you bought the last four clutch cylinder seals for a fifty-year-old BMW from JBL Pro??:dont-know

rdgrimes
01-26-2009, 02:47 PM
What? They give you guys a west-coast discount? Damn! And to think I had to pay 36¢-each for them! I hope they charge you shipping.

Got them today, they shipped FedEx and charged me not a cent. :o:

These are plain old neoprene O-rings, size 040, as far as I can see.