• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Repairing damaged speaker cabinet corners?

BmWr75

BmWr75

Top octave? pfffffftttttt
Subscriber
Received a pair of KLH 6s today. An eBay purchase. One corner is damaged on both, top left rear corner. Veneer is unrepairable, particle board is flaking. Does anyone know a way to stabilize this damage to prevent further deterioration? Would also like to color the repair to match a walnut finish.

Thanks, BmWr75
 
Register to hide this ad
jsmonroe@com said:
Received a pair of KLH 6s today. An eBay purchase. One corner is damaged on both, top left rear corner. Veneer is unrepairable, particle board is flaking. Does anyone know a way to stabilize this damage to prevent further deterioration? Would also like to color the repair to match a walnut finish.
Click to expand...

You can't "stabilize" particle board/mdf damage if the material is flaking or crumbling. Use a pick to dig out all the loose material and then fill the void.

I use these to rebuild corners, edges and any other damage that will be subjected to potential impact that would crush ordinary wood filler:

http://www.mohawk-finishing.com/catalog_browse.asp?ictNbr=113

They come in different colors, but of course precolored filler is never a perfect match and they'll need touching up. Wood stains don't color most fillers the same as the surrounding wood, and don't color epoxy at all, so I use a filler that is slightly lighter in color than the finished wood and then darken and grain it with these:

http://www.mohawk-finishing.com/catalog_browse.asp?ictNbr=132&atomz=1

http://www.mohawk-finishing.com/catalog_browse.asp?ictNbr=129

Get some scrap material and practice before tacking the good stuff. It takes a bit of time to come up to speed, but once you do repairs good enough that nobody but you will notice are possible.
 
Zilch said:
No? Search "Consolidant" here:

http://www.abatron.com/cms/

Other neato stuff there, too.... :thmbsp:
Click to expand...

I've used this (not on speakers, it's major overkill). It works well on solid wood where it can saturate the wood fibers, not so well on composite materials like plywood and particle board where the wood fibers are already saturated with the original binders. But you still have to pick out any material that is already flaking or crumbling (note where the description says it works on wood that could crumble, not on wood that is crumbling). The filler sticks I referred to are similar to this company's wood replacement product, but in a more convenient form for small repairs that comes in colors.
 
For those kind of corner damages where the speakers are particle board with veneer I usually take five steps ...if vinyl covered then one additional preliminary step....

If vinyl, then strip all vinyl first....

Prepare to repair:

1. Gently scrape off any loose particle board chips from the affected area.
2. Rough sand the vertical and horizontal surfaces to get rid of any loose or protruding bits of veneer.
3. 'Paint' the affected are with a slightly diluted ordinary white carpenters wood glue .... depending upon the effect after one coat, a second coat might be desirable.... wiping off any excess glue from the veneer surfaces with a damp cloth. This glue coating will 'stabilize' the affected area.

Repair:

4. I use ordinary wood filler to build up the corners. I sand the vertical and horizontal after each coat just to keep those areas from 'over-building' as I layer up the filler in damaged corner. Repeat until your corner is perfectly square. This step generally takes me several days to get it perfect.
5. I re-veneer and refinish.

Now, I have seen really skilled wood finishers actually cut off the corner, glue on a piece of wood same as the veneer, sand to shape and match the finish.... and the results were remarkable. But I am talking about a professional with years of experience. For amateurs (like me!), just follow the above steps and its pretty hard to go wrong.
 
I believe you can stabilize the flaking particle board to a degree, depending on the extent of the damage. I also build model aircraft and there is a technique of infusing balsa fuselages to make them more durable, that may be applicable here.

Buy a medium-bore hypodermic syringe at any drug store. Shouldn't be anymore than a couple of quarters. Get some CA glue, the type that is super-thin, not the thicker, slower curing stuff. Fill the syringe and insert the needle into the damaged area. Infuse the area with the thin CA, several times in different locations. It will dry within a minute and be super hard. Be careful not to get any on your fingers. Thin CA is extremely fast curing and generates quite a bit of heat during the process. It will stick your fingers together in very embarrassing fashion. Believe me, I know from experience. Nail polish remover will release the join if necessary.

Thin CA is available at most hobby shops.
 
sealy said:
I believe you can stabilize the flaking particle board to a degree, depending on the extent of the damage. I also build model aircraft and there is a technique of infusing balsa fuselages to make them more durable, that may be applicable here.
Click to expand...

Yes, if the material is flaking you can infuse and stabilize the part that is still in one piece (although with particle board you'd probably be better off with the epoxy because it's less likely to cause swelling in the particles than the CA). But you still can't squirt the stuff into a cavity filled with crumbly bits if you want to end up with any kind of structural integrity; you need to clear the detritus down to what is still attached.
 
Tucker99 said:
4. I use ordinary wood filler to build up the corners. I sand the vertical and horizontal after each coat just to keep those areas from 'over-building' as I layer up the filler in damaged corner. Repeat until your corner is perfectly square. This step generally takes me several days to get it perfect.
5. I re-veneer and refinish.

Ordinary wood filler works fine anywhere you're planning on veneering or covering the completed repair, and also in most face repairs and even most two-surface joints. Where it fails is at the eight places of any rectangular box, where three surfaces meet and come to a point. You can build a new corner, but the filler will usually break and crumble if there's any impact at the tip.

In the "olden days" I use to cut away veneer at these damaged corners, rebuild the box with a bit of wood and then patch the veneer (a solid wood corner without veneer would be structurally as sound, but the grain would never line up). Today, I use the epoxy-based filler and then color and faux grain. It's at least as durable as an all-wood repair, and with practice you can draw in "grain" that's actually a better match for the existing wood.
Click to expand...
 
gkimeng said:
Ordinary wood filler works fine anywhere you're planning on veneering or covering the completed repair, and also in most face repairs and even most two-surface joints. Where it fails is at the eight places of any rectangular box, where three surfaces meet and come to a point. You can build a new corner, but the filler will usually break and crumble if there's any impact at the tip.
Click to expand...

Well, I have done corner fills and re-veneers as I described, including on the front corners and have then re-veneered the sides, top and face. Under normal use I cannot imagine there being any problem but if the total idiot that tripped and dropped the speaker in the driveway the first time (that was me!) did it again on the same corner then I reckon you would be correct ... the filler would break. But otherwise I can promise that repair is total. Remember that the filler is now under the veneer.
 
Tucker99 said:
Well, I have done corner fills and re-veneers as I described, including on the front corners and have then re-veneered the sides, top and face. Under normal use I cannot imagine there being any problem but if the total idiot that tripped and dropped the speaker in the driveway the first time (that was me!) did it again on the same corner then I reckon you would be correct ... the filler would break. But otherwise I can promise that repair is total. Remember that the filler is now under the veneer.
Click to expand...

What I meant was that ordinary wood filler works fine everywhere under a reveneer, and also just fine for surface repairs without reveneering, everywhere except at the corners. Sorry if the post wasn't clear.
 
To avoid reveneering, I prefer white car bondo and trompe l'oeil...I never know when one of my speakers is going to launch itself like my Infinity Quantum did during the 1994 Northridge quake. One stayed standing upright while the other managed to fly over a precious HPM-200.
 
I am a furniture repair tech, I can vouch for the Mohawk products, the epoxy stick is top notch stuff!! cut off what you need and mix it by kneading it until it is a uniform color starts to feel a little warm and the press it in place, you can use a putty knife dipped in to water to shape it, water keeps it from sticking to the blade. let it dry about 30 min or so and you can sand it just like wood.
 
Last edited:
Unfortunately, just applying filler over failing particle board (even if you think you've flaked off the "bad" portions) will fail sooner rather than later. The affected particle board will continue to expand and contract due to temperature and moisture fluctuations. This will cause any filler to fail.

You must stabilize the affected particle board first. Once this is completed, the filler is cosmetic and the repair will last for years. No matter how amazing a filler material is, it's not a "glue". And brother, or sister, what you need to hold that old particle board together is glue.

I have my preferences, but any good two component epoxy resin that has a pot life of about an hour at 68 degrees F will suffice. And, you do not want a resin system that develops an Amine Blush. That's a waxy film that develops when many epoxy cures. This is one of the two reasons you must sand to get filler, glue or paint to stick and last. And sanding a non-smooth surface is darned near impossible.

Using a heat gun, warm the area to be repaired until it's toasty. Apply your mixed epoxy resin to the failing particle board. Keep applying until it sits on the surface. Let the resin more than fully cure, read the label ya bone.

Now the particle board is restored and you can do with it what you will.

Biggles
 
This probably isn't going to fix your dilemma, but I sometimes use an iron with steam on top of a towel to make scratches and other damage less noticeable. The heat and steam will sometimes pull the scratch out a little. If you try this, be careful that you don't melt the finish or make the color fade.
 
cablephil212 said:
You guys realize that it's a 5 YEAR OLD thread, right? :D
Click to expand...

YES !!! But after restoring the Altecs and not finding another inspiring restoration job, I've been kinda in limbo over here. Restoring old, flaky and hugely failing particle board on speakers is something I can do!

Plus, at the beginning of this thread, it was stated that there's nothing one can do to restore rotting particle board. Admittedly, I didn't read through the following comments. I just figured I'd pop in and spew forth. That's all there was to that.

Biggles
 
You must log in or register to reply here.
Back
Top Bottom