Woofer dust cap repair advice, HELP

My nephew with whom I am most displeased is visiting our home. Last night he decided to poke the dust cap of my Kharma speaker three times. Fortunately he did not perforate the cap, but it is dented in.

Does anyone know of a way to pull the cap back out?
I had a pair of keltiks and the midrange dust cap was pushed in, I used the attachments of the vacuum and sucked it out,well it worked for me so I don't see why it would not work for you. Douglas.
I've seen a tweeter dust cap massaged out with a finger before. The guy rubbed around the dent and it popped out. The dust cap on your woofer is probably thicker...

I have also heard of people using a vacuum cleaner. This can probably do more harm than good, though, unless you have an attachment with an adjustable vent so you can make the vacuum less severe.

Others will hopefully have some first hand experience to offer you. Good luck.
I sorry guy.

Thats really to bad. You could try using low tack painters tap and lay it across the cap. Then you can try to 'pop' it back out.

If that does not work you could move your way up to regular painters tape and then possibly masking tape. If that still does not work you could try the clear packing tape.

I am not sure what the caps are made of on your speaker. If it is some form of plastic it will be harder to pull back out, but it will take more force and a sticky tape to do it.

If cap is paper it should come back out pretty easily but a stronger tape could take some of the cone with it.

I would experiment of similar surfaces before you try anything.
Hope you have good luck fixing it.

Let is know how it turns out.


P.S. You could also let your nephew and any other small children know that any poking will result in there finger be severed with a butter knife and then feed to the birds. :) Just kidding. But you might want to look into getting some sort of grill for them. Then when kids come over you can have a little more peace of mine.

I am always worried about some one knocking my speaker over of its stand. My wife says if I am that concerned I should put them in the corner.
She just doesn't understand. :(
buy the cheap breast pump(for breast-feeding moms), it'll work!
If you have access to tools, you might consider cutting a hole slightly bigger than the dented area in a bracing material, perhaps 1/4" plywood would work. If the dent is say 1', cut the hole about 1 1/2" and bevel the edge that will go against the cone so no sharp edge will damage the speaker. This would be held against the perimeter of damaged area while you try to pull the dent. Not knowing the textural characteristics of the area that is dented, your options might be; if the area is smooth, an appropriately sized suction cup might work nicely. If textured, an implement tipped with a ring of something like blu-tack might allow adequate suction to pull out the dent. It all depends on how sturdy the dented area is, the material, and if you can devise some means to get a pull on it. Perhaps a call to the speaker manufacturer would be in order for suggestions. Good luck!
Just another good reason NOT to have kids!.....or anyone else's too!
Try blu-tak. It's commonly available in the UK for just a couple of bucks, and in the US it's sold by audio dealers to hold speakers to stands. They usually mark it up to about ... er $20 (snigger).

Seriously, it might work, and it doesn't leave any residue.

You might also try sticky tape or masking tape.
It's so ironic that there was a thread about mixing speakers and kids on agon just a couple of days ago. Having a very active 3 yr old I know all about this stuff. My advice is:

1) separate room for equipment if possible
2) toys are drawn to reflex ports like space debris to a black hole. Plug-em !
3) Leave the grill cloths on so that the drivers aren't visible.
4) Don't leave the grill cloths on as they can quickly be defaced.
5) Try not to get mad .. they didn't mean it.
6) You were once like them. We all were. Except me.
7) One day they'll become brain surgeons and make you proud.
8) er, that's it.
Try the above recommendations first. Worst case, you could remove the woofer, remove the magnet from the woofer and then push the dust cap back from the other side. That is very tricky and it is particularly tough to get the magnet back on right since it must be parallel at the outset before you screw the magnet back on. It takes a while to get that right. I did all that just last weekend for a different reason. Please be sure to call the manufacturer first since your speaker may be different and might require other techniques and tools. I just needed some allen wrenches and a putty knife. Again, be sure you contact someone who knows these speakers before doing this. Good luck.
Considering past history, do you think the children in that family are pre-disposed to that activity?
Just wondering.

'Uncle Greg'
Some woofers have vented pole pieces with no screening in the vent hole. If such is the case, you can stick a long pencil through the hole in the back and use the soft eraser to try and massage the dents in the dust cap back into place very gradually.

It this isn't feasible, i would try using some masking tape wrapped around your fingers and taped back onto itself. This will allow you to apply as much pressure as you need to in order to get the tape to adhere to the cap and at the same time, allow you to vary how much tension you put on the cap while pulling the dent out. You can then use your other hand to stabilize the cone so that you're not pulling on it sideways, etc... The masking tape may be sticky enough to grab the cone but it will break loose if you pull too hard. This minimizes the potential to damage the driver and at the same time, won't leave any type of residue behind.

The use of some type of small suction pump or a "leaky vacuum attachment" may also work if you can find the right size and shape attachment. If you try to use a standard vacuum, good luck. I'm sure that it can be done, but it sounds a little risky.

As a side note, i would not worry about this too much. On most woofers, the dust cap is not very critical. This becomes more critical as the driver is used to reproduce higher frequencies. Sean

PS... I bet that someone's blood pressure about blew their eyeballs out of their sockets when they saw this. How much smoke poured out of your ears??? Is the child still alive???
For driver speaker repair Orange County speaker repair is great and reasonably priced. Jallen
I tried using masking tape to pull the cap out and it did not stick to the cap. I'm not sure what the cap is made of but it looks like handmade paper. For that reason I'm a little leary using a full sized vacuum. I tried a little hand held Dirt Devil thing but it didn't have enough sucton.

Unfortunately my kids are old enough that we no longer have the breast pump suggested earlier. I think Marakanetz just wanted to say 'breast.' : )

The smartest thing for me to do would be contact Kharma and see what they might suggest but I would still appreciate any suggestions.
I spoke to a speaker manufacturer's customer service department about this issue just last week. They advised that they had done alot of testing on damaged drivers and it was not worth replacing it unless the dent impeded the movement of the cone. In fact, they told me that they had a speaker in their listening room damaged the way yours was when an elementary school class had come for a factory tour, and they had allowed it to remain in their room as is. They also advised that people frequently make matters worse when they use tape to try and fix the dent. Keep the grille cover on so you don't have to be reminded of the dent.
I have had very good luck pulling out dented dust caps using a pin or a needle. Just poke it through the dust cap next to the dent and manipulate it so as to press out the dent from the inside. When you withdraw the pin there will be a tiny hole where the pin was. If this bothers you, plug it with a speck of glue.

You need two things, one is a quick fix, the other is more long term, I have both.
1 - Scotch packaging tape is more adhesive than masking tape and works great. Cut a small piece and make sure your fingers do not come into contact with the adhesive. Apply the small piece of tape and just rub it gently with your finger nail. Then leave it for a couple minutes. Pull it out slowly, not directly forward, at an angle so it stays adhered for longer.....voila!
2 - Barbed wire. I have a roll in the garage, it doesn't look good but it sounds ok and works a treat with kids.

Always glad to help

The dust cap shouldn't affect the sound. Use blue tack or masking tape to do what you can.

Otherwise, there are speaker repair companies that can cut off the old caps and glue on new ones: Tri-state loudspeaker in Aliquippa Pa is the best I've seen.
Hello Nate. Yes, the smartest thing to do is call Kharma for their professional advice.

However, since you asked, I have a little story for you. Awhile back, I was in a professional music store where they sell band and recording studio equipment. I had a passing interest in a beat up pair of Yamaha NS40 studio monitors. The salesman wanted 50% off retail price and I was only willing to pay 75% off retail considering the cabinets were terribly abused and (3) of the woofer dust caps (made of white paper) were pooched in.

The salesman said the (3) pooched in dust caps were not a problem...and I said yeah, right. Sure enough, the salesman had a technician repair all (3) of them in less than (10) minutes right before my eyes.

The tech carefully hand twisted a 1/16" drill bit into each dust cap. He then straightened out a paper clip, curled the tip of the paper clip slightly with needle nosed pliers, carefully inserted the curled tip of the paper clip into each of the 1/16" predrilled holes, and in just a few short minutes the tech had the dust caps looking like new. The tech finished the job nearly to perfection with (3) small dots of Elmer's white glue.

I then had to eat my words about the pooched in dust caps. Still yet, I had to pass on the 50% off retail before the guy started refinishing the beat up cabinets.

Nate, I hope this helps. I like Elevick's idea above of gluing on new caps if my idea does not work out for you.

Nate...I have one other possibility for your consideration. Last Christmas, I received a complete 1/2" diameter set of "Mini Attachments For All Vacuums." I have not used it yet, but it says it is adjustable for both full sized and hand held vacuums. It is made specifically for the cleaning of computers, office machines, and stereo & video equipment. It looks to me that you can get adjustable suction in very tight spaces with this clever gadget. I don't know at the moment where my sister bought it, but I'm sure you could quickly find a little set somewhere here on the internet.
Use a pin! Unless you are performing the work in full view of a customer, in which case the 1/16 drill and carefully bent paper clip will make it look like rocket science.
Eldartford, I often follow Nrchy's threads and answers; I like Nrchy. I think Nrchy posed the question to us because he wants a nearly perfect repair job. Nrchy may get just one shot to either get it right or wrong with a pin, paper clip, or whatever.

I have personally tried the amateur pin method (and yes, even pro audio dealers suggest the same) about 10 times over the years. About the 9th try, I got lucky and the dent came right out with the pin. The repairs I did on speakers 1-8 and 10 were amateurish and not to my satisfaction. Either end of a pin leaves score lines or pooch marks on the fragile paper dust caps as you try to pull out the dent. The friction fit of the pin in the paper can also cause additional creases in the paper dome.

No, it is not rocket science, and we know that the dented dust cap is trivial in the grand scheme of things. However, I would like for Nrchy to be 100% happy with his repair, because I relate to perfectionism.

Nrchy, have you ever seen anyone "spoon" a dent out of a car? Car dealers use these travelling "artists" to make dents quickly and magically disappear. Think of the curl in your paper clip as your spoon to massage the dent forward and out.

Earnestmoney...I guess I must be highly skilled or damn lucky, because the pin always works well for me.
Eldartford how often do you dent your dustcaps??? : )
My primary speakers being Maggies,I have no dust caps to dent! However, in recent memory I found a dented cap on a dynaudio box that I was using for rear channels, and I did the pin thing with perfect results. In the past 50 years I have probably fixed half a dozen drivers for my own and kids speakers.

A suggestion...find an old (perhaps blown out) driver, dent the cap, and try fixing it. This would give you confidence to tackle your good speaker.
Eldartford, I am impressed with your skill and/or luck. Great advice to Nrchy to practice first on some old or blown out drivers.

I tried BOTH the pin and paper clip "thing" last night on an old blown Yamaha woofer obtained from my nephew for free. The funny thing is NEITHER method worked for me. I discovered that the dust cap permanently retained the "memory" of the dent. Every time I popped out the dent, it would just pop back in. LOL. After repeating this a few dozen times, the dust cap started coming off cleanly at the seam. I carefully and completely removed the dust cap. I have had little luck in massaging out the dent with my fingers, let alone the pin and paper clip. Yes, I must be an unlucky klutz ;-)

Yes sir, I agree with Eldartford on the practice before proceeding to your Kharma. Perhaps you can get a lot of free practice at your local junkyard or obtain some cheap junk speakers for experimentation.

Now, I fully understand the speaker manufacturer's response to Cmp.

Best wishes to all,
Earnestmoney....I should mention that "soft dome tweeters" are the drivers that I have had the best luck with. (essentially a perfect repair). Drivers with hard caps are more difficult, and may show a crease, although the dent will be gone.
Eldartford, you make me "work" to explain things in detail just like my older and wiser brothers (fully intended as a compliment).

Nrchy, remember to practice and good luck.

I got an e-mail back from Kharma, and they recommend sticky tape to try to pull the cap back out. Since they gave the go-ahead I will try this. Masking tape did not work, but I will try something more aggressive.
Duct tape .. that's what you need. Preferably an old roll that's sat in the garage for a few long hot summers and is starting to ooze its glue and has dust stuck to the edges. If it's stuck to the self or drawer you find it in so much the better :-)
Yeah...what was I thinking...duct tape...that's the ticket, and btw, the Green Bay Packers suck! ;)
Not all the time!!!
I know.......devil must've made me say that...as a typically bumming Bunglers' fan :(
Well, after much fear and trepidation I applied a piece of duct tape to the dust cap of my woofer. After a good dozen attempts it pulled back out. It's not perfect, but it's better than 90%.

I would call it a success.
Any audible differences?
Nickway there was no audible difference, it was purely a cosmetic issue.
I've been on "pins and needles" ;) Seriously, cheers to your success, Nrchy!!! :)