PA speaker top hat rusted on

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I'm stripping some old PA cabinets - I'm taking the parts out, and I wish to recycle the battered ply boxes by applying a new skin of 5mm bamboo.

The cabinet bases have top hat mounts that are not flush, so I'd like to remove them, to make the skin job easier (and get rid of the weight). There are 4 big slot head fasteners which secure the top hat (stock photo attached in case I used the wrong term) that are rusted, so the slots have soft edges, and I can't get them to budge.

I don't have a grinder or any metal-specific power tools. What's the easiest extraction method? e.g. should I try drilling the slots deeper, so a screwdriver can get better grip?

I do have a couple of fall back options, such as simply jigsawing a big circle around the entire top hat mount.
 

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why not just drill them out? are you not re-installing the top hat mounts? if you are i'd drill them out and step up on screw size and length to accommodate the new "skin" to re-install.

if you pick your sizes correctly and take care with depth you can drill away the head of the screw and remove the top hat, even if screw shafts are left in the wood just spin the position of the top hat on re-install
 
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are you not re-installing the top hat mounts?

Nah - I'm gonna repurpose them as non-audio furniture: storage chests / seating.

They aren't in good enough shape to restore, and the original build quality was too sloppy to make it worthwhile e.g. the pictured brace felt wobbly, and I was surprised that I could simply pull it out by hand, with no effort - meaning it wasn't bracing anything, just adding weight. The box is held together with a too-frugal amount of glue, and no screws, just the wire-like nails that I normally see used on trash such as disposable shipping pallets.

The quality of the drivers and metal parts is good / interesting - the crossovers certainly had a decent amount of engineering lavished on them, and are built more strongly than the enclosures :)
 

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Just to help out a bit with the cabinets. The braces are panel dampers. The smaller you divide the panels into, the higher the frequency that will excite the panel. High enough and the woofers won't have an adverse affect. So not braces in the way you are thinking. I can't judge the glue but the brad nails used to assemble it are simply the clamps until the glue dries. It's the same construction I use. Best way to get a lot of cabinets built in a short time.
 
Just to help out a bit with the cabinets. The braces are panel dampers. The smaller you divide the panels into, the higher the frequency that will excite the panel. High enough and the woofers won't have an adverse affect. So not braces in the way you are thinking.

I see how that could be the principle they were shooting for.

Me: I'd probably use something a bit more space and weight efficient than big hunks of soft pine, and I'd also cross brace the side bits.

I can't judge the glue but the brad nails used to assemble it are simply the clamps until the glue dries.

It seems to have aged badly and/or to have been applied while drunk. As well as the pictured free floating bit, the other box had a part of the front panel hanging loosely on bent brad nails. These loose sections probably used to buzz at high (gigging) sound levels.

It's the same construction I use. Best way to get a lot of cabinets built in a short time.

It seems pretty common. I'm also re-purposing some JBL cabs that had essentially the same construction. The JBLs had better strength:weight and gluing (nothing was falling off / flapping loosely).
 
Community Sound and Light used to be a good Pro equipment brand, you mentioned good drivers and showed a good quality crossover board.

My take is that those were good, well thought and made cabinets (you even found them close to JBL construction) , but 10/15 years Touring over 20 years ago certainly turn any cabinet into jelly.

I bet if you could properly reglue and clamp those cabinets, they would become very usable again.

Either as speaker cabinets or plain furniture.
 
Community Sound and Light used to be a good Pro equipment brand, you mentioned good drivers and showed a good quality crossover board.

Indeed. I got the boxes cheaply, hoping to salvage the good parts, specifically the M200 midrange drivers, which are reputed to be excellent. I was saddened to discover that one M200 driver is intact, but the other was simply missing.

(you even found them close to JBL construction)

That's not a good thing! I found both examples to be slightly disappointing, relative to their legendary status, e.g. both used fairly soft, cheap-looking ply.

The JBL boxes were low end, for them (cabaret series); the Community boxes may have been similarly entry level, and not representative of their better gear.

but 10/15 years Touring over 20 years ago certainly turn any cabinet into jelly.

They obviously got bumped in and out of venues a lot - many scrapes, splintered edges, plus bad storage: water damage, as pictured.

I bet if you could properly reglue and clamp those cabinets, they would become very usable again.

Either as speaker cabinets or plain furniture.

I certainly hope so. That was my stated intention in line 1, post 1 :)

My JBL cab re-use, and a trial run of the bamboo skin is in post 39 here:
paper cone open frame driver for front horn

I like re-using boxes partly to save materials, and partly because I like the constrained format - I sometimes get bogged down if I have too many choices.
 
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