Let's Try to Fix a MW6511 Damaged in Shipping...

VR3

I commend you for the effort and dedication... other than that you are crazy man! :-P

brgman

Saftgeek wrote: »

Brg - that made me laugh out loud. I've blessed this thing with a few unholy words... I completely trashed my handy-dandy magnet moving jig. The plastic isn't tough enough to hold on and they stripped out. I will pick up an aluminum coupler tomorrow and try it. I know... I'll order a replacement so I can get these back into play. I just hate giving up.

Stay tuned... I'm sure there'll be more comic relief tomorrow night.



-Saftgeek

hang in there
just sayin what i would do.
you obviously have quite a bit more patience in the well than me

PolkieMan

ahh so maybe the magnet did not move the basket was bent causing the problem

Saftgeek

I think I may have both issues. I know the basket is bent but when I removed the driver I could spin the magnet. I am hoping a stouter jig may allow me to move the magnet in very small increments. As hard as this has been I can't imagine only having 20 minutes to get the voice coil centered. I was hoping I could just put JB Weld along the magnet instead of in between. I'm serious when I tell you that magnet is strong!

More madness to come.

-Saftgeek

Mr. Bubbles

I am all for saving the older driver if it can be done and i commend your effort. in no way am I trying to convince you to do otherwise. However, after reading this thread and looking at your pictures, I would tend to agree with others that this may be a waste of time. but hey, i have wasted plenty of my own time in the past learning things as well.

My reasoning is not due to the magnet shift; this is a relatively easy fix. The bent basket will be the major part of the equation. though you don't have good pictures of the basket. the one you do show indicates that the mounting flange is bent towards the magnet somewhat. bending this flange only in that direction will not effect the centering or plane of travel the voice coil rides in. however, if the impact that caused this was hard enough, it could actually have stretched the basket away from its center (or towards its center depending on the directional force of the impact on the driver), in effect elongating the basket so that it is not completely round anymore. This would pull the voice coil off center and possible change the angle of the plane the voice coil travels in. The best way to determine this for your repair purposes are to make some measurements without the magnet in place. 1st measure the centering of the voice coil in the top plate. You will want this close but will be able to make some adjustments if this is not perfect. keep in mind that this could have been slightly off at production. the pole piece is more critical. next take a very accurate square and measure the voice coil in terms of it being square with the top plate. Do this in several locations around the voice coil. If this is not square, i would give up, as unless you have the ability to make a press to properly clamp and straighten the basket to its original roundness it will never be correct. If however the voice coil is square to the top plate even if the top plate is slightly off center with the coil but not rubbing, you can probably fix it. I agree with a previous poster that simply smearing JB weld is not sufficient to keep the magnet and pole piece square even if the top plate is. I would also recommend some clamping force as well as a slower setting adhesive.

Good luck.

Saftgeek

Update time... I don't want to jinx myself so I'm going to say I MAY have actually repaired the speaker. The reason I say may is because it is still in the new jig and I haven't let the tension off of the screws yet. I picked up a thicker PVC coupler and built a new magnet setting jig. Like I said last night, the one I was using stripped when I tried to put the necessary force to move the magnet. I had to work at it, but it seemed to work. I took it apart again and then used JB Weld between the magnet and the driver basket. Once I got it back together I had to really work fast to get it back in the jig and manipulate the magnet where there was no interference. I cannot notice any rubbing at this time. I'm concerned when I let the tension off that the deformed basket will again cause the voice coil to rub.

Before anyone says anything... I tried to true up the basket, but that just wasn't going to happen. The speaker has a foam gasket and I'm pretty sure that should seal it up just fine. I don't want to get ahead of myself. I'll know tomorrow morning if the JB Weld holds and the voice coil stays true.

I did order a replacement today. I really had little faith in actually getting this thing fixed. I took a couple pictures, but I'm not posting until I figure out if it works. I have to re-fit the dust cover on the coil and glue it back into place. I'm planning to use superglue... If anyone has a better suggestion, please let me know before tomorrow night.

I wasn't going to post till tomorrow but I couldn't wait... I'll let you all know how it works and sounds. Wish me luck!!!

-Saftgeek

cwsmith68

Saftgeek wrote: »

I'm planning to use superglue... If anyone has a better suggestion, please let me know before tomorrow night.

I wasn't going to post till tomorrow but I couldn't wait... I'll let you all know how it works and sounds. Wish me luck!!!

-Saftgeek

Kraft glue is what you should use for the dust cover.Should be available at any hobby/kraft store or even Wal-Mart.

Saftgeek

Thanks CW... I think I've got some of that laying around here. Plenty of school projects all the time...

-Saftgeek

brgman

Lasareath wrote: »

I don't like the new polk drivers because they don't say polk audio on them and you have to cut the notch manually where the screws go.

This is critical for you to remember geek!! otherwise you can ruin it during installation.

mesquitehead

PolkieMan wrote: »

ahh so maybe the magnet did not move the basket was bent causing the problem

My thoughts exactly, get the basket straight first otherwise nothing is going to line up properly anyways.

mesquitehead

cwsmith68 wrote: »

Kraft glue is what you should use for the dust cover.Should be available at any hobby/kraft store or even Wal-Mart.

Good call!

mesquitehead

Take a couple short lengths of 2x4's and sandwich a couple of 1/2" OSB/plywood or whatever blocks in between the 2x4's with screws then slide the edge of the basket outer rim in there and gently bend it back into place.

PolkieMan

Yea I think you and I got a little bidding going on that last 6511 was it like $70? by the time you figured in shipping, you won :biggrin:

Lasareath wrote: »

Default UPS shipping caries $100 of insurance.

I don't like the new polk drivers because they don't say polk audio on them and you have to cut the notch manually where the screws go.

Both my 1.2tl's have all originals. To me they look more authentic. I have (6) 6511's & (9) 6503 spares. Bought all on eBay. Always looking for more.

Welcome to Club Polk!

brgman

$70 for a 6511??

Saftgeek

Well, here is the semi-final post in my repair endeavor...

I decided to give it another shot last night. I totally destroyed my first jig, so my first job was to build another. I think I've tapped at least 50 1/4" x 20 holes during this project. Once the jig was built I tightened the speaker into place and began trying to manipulate the magnet into place. Imagine my surprise when it dropped in and I was able to move it to the exact position... Next step, apply the JB and do it for real. Here is what it looked like when I got it dialed in just right...

I used a battery and made sure there was no interference or rubbing. Once the JB Weld dried I took the speaker from the jig and it was still set. I'm not sure why I thought it may not hold, but I figured something unexpected was going to surface when I removed it.

I now had to re-set the dust cap I'd removed. When I cut it out I took my time and made sure I cut through the part of the cap that had the coating applied. I was afraid if I'd cut through the fabric it may start to unravel. I'm really glad I did this because you can't tell it's ever been cut out. I used a loop of blue tape so I could position the dust cap just right. This kept me from damaging or crushing the cap while trying to move it into the correct position. I used Super Tacky Craft Glue because it is extra strong and it's what my wife brought back from the store. I used a toothpick to make sure I put the glue exactly where I wanted it. I put a weight on the dust cap to make sure it was seated while the glue dried.

Here it is... One difficult darned MW6511, ready to go back to work. I'll let the glue set up tonight and install it tomorrow night. I will try it out at high/mid/low volume and see if it holds in there. Now that this little project is done I have another something to do... It seems I've received a package from Polk Audio today with some replacement tweeters... Let the good times begin!:cheesygrin:

-Saftgeek

mesquitehead

I admire your effort amigo! Hope it works out well when it is installed.

Saftgeek

Fingers crossed Mr. M. I'm hoping it passes the low volume test. If you remember from our conversations you couldn't tell this thing was damaged at high volume. Only when used for home theater speech and background music did it vibrate. I really think it's going to work... I'll text you tomorrow night and let you know.

-Saftgeek

PolkieMan

yea I got one for $50 shipped from audiocrave they are hard to find

brgman wrote: »

$70 for a 6511??

PolkieMan

Well you deserve for it to work after all the effort that you put in it. You will love the new tweeters they are much smoother.

Saftgeek wrote: »

Fingers crossed Mr. M. I'm hoping it passes the low volume test. If you remember from our conversations you couldn't tell this thing was damaged at high volume. Only when used for home theater speech and background music did it vibrate. I really think it's going to work... I'll text you tomorrow night and let you know.

-Saftgeek

Saftgeek

The test is done... The driver works flawlessly. Low volume, mid and loud. I'm very happy this one stayed out of the dump...

Saftgeek

gdb

Congrats !

(probably won't be stellar,though)

Saftgeek

GDB -

stellar [ˈstɛlə]
adj
1. (Astronomy) of, relating to, involving, or resembling a star or stars
2. of or relating to star entertainers
3. Informal outstanding or immense companies are registering stellar profits
[from Late Latin stellāris, from Latin stella star]

1 & 2, definitely not... 3 - I'm thinking yes!:cheesygrin:

I really enjoyed the challenge. I listened to 4 cd's tonight and I couldn't be happier. I have my new tweeters to install then I'll tackle crossovers.

-Saftgeek

gdb

It was an off-hand, obscure reference to a resident arbiter elegantiarum here. Enjoy the fruits of your labors in spite of the nayersayers !

drumminman

Saftgeek wrote: »

GDB -

stellar [ˈstɛlə]
adj
1. (Astronomy) of, relating to, involving, or resembling a star or stars
2. of or relating to star entertainers
3. Informal outstanding or immense companies are registering stellar profits
[from Late Latin stellāris, from Latin stella star]

1 & 2, definitely not... 3 - I'm thinking yes!:cheesygrin:

I really enjoyed the challenge. I listened to 4 cd's tonight and I couldn't be happier. I have my new tweeters to install then I'll tackle crossovers.

-Saftgeek

My hat's off to you saftgeek. I was in the camp that you'd only be wasting your time, but you made it work. Congrats!

FWIW I have a replacement MW (a 6510) from polk and it seems to sound just like the original I poked a hole through accidentally. However. . . . . . . . . . . . . I did buy an original 6510 from a member here just in case

nspindel

Well I'll be damned. Good work!

Oldfatdogs

Im glad you got this driver done,you are a persistent man with more patience than I have.Good on you Saftgeek.
Dan

PolkieMan

GFY good for you , I love when I meet people that just won't give up!!!
It will be stellar! Better than new! You are the speaker repair specialist!
If you don't think vintage good 6511 are hard to find I challenge you to find one.
Now do the tweeters :biggrin:

Saftgeek wrote: »

The test is done... The driver works flawlessly. Low volume, mid and loud. I'm very happy this one stayed out of the dump...

Saftgeek

mesquitehead

Congrats for sticking with it. And to the naysayers....hows that crow tasting?

Mystery

Saftgeek wrote: »

GDB -
...
1 & 2, definitely not... 3 - I'm thinking yes!:cheesygrin:
I really enjoyed the challenge. I listened to 4 cd's tonight and I couldn't be happier. I have my new tweeters to install then I'll tackle crossovers.
-Saftgeek

Congrats!
Now if you make a video of what you did, it'll be definitely stellar. :biggrin:
At least for me so I can work on mine as I don't get all that jig making thingy from reading only. :redface:

dorokusai

That driver will never spec even if it does play sound and move air, which is a basic function of any transducer. If that doesn't matter, awesome. The jig idea had been done by dozens of folks over the years with varying success. Great work Saftgeek as one of the better Polkies to figure out a method to realign VC's.

Mark