Stripped screw heads/ T nuts, help!

[mikebake]

Any tricks/tips for getting these out? Was trying to remove woofers from 4655BK's, a few screws have the heads stripped; can't get T-nuts backed out from back side to help either. Durn it.

[grumpy]

ever watch cartoons where a handsaw comes
through the floor, circling the 'target' ? :eek:

-grumpy

If the head is far out enough to grab w/
locking pliers, you might be able to pull hard
enough to keep the T-nut from spinning...then
unscrew while pulling... ? or drill small hole from
the side toward/through the t-nut & insert
something like coat-hanger wire (again to keep
t-nut from spinning.

[Robh3606]

That sucks!!

That is one tight cabinet you have no room at all on the sides and bottom. You try pulling out the connector panel?? You might at least be able to get a hand in the back for the sides and bottom. You try one of those special stripped screw bits?? Maybe you can carefully drill the heads off?? Tuff one.

Good Luck Rob:)

[subwoof]

hey there - been there / done that.....

use a drill with a 11/64 bit and drill out the head.

after you go down the thickness of the head it will snap off.

You might have to grab the t-nut from the back. Use a pair of visegrips to hold it.

DO NOT USE YOUR HANDS or you will have scars to show your grandkids. Those t-nut spikes are NASTY.

Another tip - use a NEW #2 phillips bit - put it into the screw and hammer it down tight. THEN use a 1/4 nutdriver to turn it.

have fun...:)

[scott fitlin]

Hardware stores carry screw extractor sets. You will have to drill the head first, then you insert the extractor tool into the head and turn. This will work, but only if the T-nut is still grabbing the wood tight. If the T nut is spinning freely, you will have to work with pliers or vise grips to hold the T nut, while you extract the screw.

If you just drill the screw head till it snaps off, you will still have the screw shaft to deal with getting out.

[DavidF]

Two methods learned from motorcycle repair fun days. If the metal is are fairly soft, use a hack blade or similar to cut a slot for a regular screw driver. Another is to use a reverse drill bit ( have not looked for one lately but used to be fairly common). This has the tendency to back the screw out as the bit bites into the screw.

Both methods will create metal chips that may be a problem around the magnets, so should be the last resort type.

DavidF

[Steve]

Aloha
One of the best buggered screw removing extractors I have found is available at Sears, of all places.
I have used many different types in the past, square, round and others.
The latest ones offered at Sears, ..have removed screws none of the others I have used before has with out drilling....Costly, at least over here.....
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00952157000
The web site has them a lot cheaper than out our local store. The kit I got of 4 of them was $20 plus...OUCH!!!.... worth it though....
Sears item #00952157000
Mfr. model #720SR

Good luck....
Might want to place a piece of plywood in front of the speaker cone just in case....

Steve

[Steve]

Almost forgot...
With the corrosion where I live and lessons learned from the past...
I always add a small dab of anti-sieze ( from local auto store ) to the screws, bolts etc. that I see I might want to remove at a later date. I put it on just about everything....cars, spark plugs, lug bolts, screws, nuts, even computer hardware.
A small amount goes a long way......If not anti-sieze, then some plumbers grease.
A product called bulb grease works wonders for light bulbs outside and autos. No more glass breaking away from the socket on those outside flood and motion lights etc.


Steve

[mikebake]

Helpful replies; thanks. I'm on my way!

It all started because of a (seeming) problem with one of the crossovers, and my need to extract it.................

[subwoof]

the threads on the tnuts always seem to go bad - esp when a drop of debris ( glue / cloth from cone edge ) gets into the hole.

Once it's jammed, NO extractor, easyout,etc is gonna work. Drill it's tiny head off and be done with it...

btw I have some of those crossovers sitting in my parts bin if needed.

sub

[mikebake]

Originally posted by subwoof
the threads on the tnuts always seem to go bad - esp when a drop of debris ( glue / cloth from cone edge ) gets into the hole.

Once it's jammed, NO extractor, easyout,etc is gonna work. Drill it's tiny head off and be done with it...

btw I have some of those crossovers sitting in my parts bin if needed.

sub

Thanks, Actually I have the original crossovers; these were some "custom" ones; not sure what is wrong with it yet, need to get it out and check it out. May have to put original back in for meantime. Custom jobbie had some HF compensation, etc.

[HenryW]

Drimel tool has always been my friend for this - try the slot cut first and you can try several of the above discussions all the way to extracting the T nut with the fine/small bits. I have sucessfully removed a T nut and replaced with a larger one in the same hole.

Good Luck.

[whgeiger]

MB,

1) Drive out T-nuts with punch and hammer from front of baffle. Do not use any method of removal the forms metal dust or chips. Theses will get lost in the acoustic lining and may find their way in to the magnetic gaps of the drivers later.

2) Replace all t-nuts with the referenced binding nuts [1]. Note you must cut off one side of these so that they clear the enclosure cutout for the driver. After doing that, clean them thoroughly before installing them in the enclosure using three small wood screws.

[1] Binding Nuts, McMaster-Carr Catalog
http://www.mcmaster.com/param/asp/psearch.asp?FAM=nuts&FT_153=63297&session=desc=Nuts;nuts;153=63297

Regards,

WHG

[mikebake]

Originally posted by whgeiger
MB,

1) Drive out T-nuts with punch and hammer from front of baffle. Do not use any method of removal the forms metal dust or chips. Theses will get lost in the acoustic lining and may find their way in to the magnetic gaps of the drivers later.

2) Replace all t-nuts with the referenced binding nuts [1]. Note you must cut off one side of these so that they clear the enclosure cutout for the driver. After doing that, clean them thoroughly before installing them in the enclosure using three small wood screws.

[1] Binding Nuts, McMaster-Carr Catalog
http://www.mcmaster.com/param/asp/psearch.asp?FAM=nuts&FT_153=63297&session=desc=Nuts;nuts;153=63297

Regards,

WHG

Hi Bill, thanks for the reply; I'm not quite sure I followed you. Use a punch and hammer and strike the screw head? ?? I know I'm dense here, but the head isn't going to go through the hole, no???

[whgeiger]

MB,

So, screws are still in place and now they are ‘captive spinners’!

Then do step (0) first.
0) Cut off most of the head with a Dermal Tool. Periodically sweep work area with a magnet while doing this. Stabilize screw with forceps and make like a dentist. Use a carbide burr to clear out most of the head. Then go to step 1).

Do not like T-nuts. Use the referenced [1] binding nuts instead.

Good Luck,

WHG

[Tom Loizeaux]

I had a problem with "spinning" T nuts, but my situation was a little differant.
When I was removing the rotatable panels on my 4343s, I found that several of the T nuts had lost their anchor in the rear of the baffle. I removed the speaker, reached up inside and jammed a small screwdriver or awl up tight to the edge of the T nut and loosened the screw carefully from the front. Once I got them all out, I cleaned the wood under the T nuts, and repaired the chewed up area with wood glue. The next day I replaced the beat-up T nuts with new ones, hammered them into place, and reattached the panel. I put a little dab of grease on the machine screws and pulled the T nuts up tight as I snugged the screws back in. They've worked fine ever since.

Tom

[RedZCar]

You don't say if they are Phillips head or slotted head screws. If they are Phillips head, get yourself an impact screwdriver, available from either a motorcycle shop or from Sears, about $12-$15. It is little money compared to the damage you could do using the wrong tool or wrong approach. Any metal filings or chips get into your v/c gap and you will regret it!

If slotted head, then use David F's method, but take great care in prepping area (masking tape, etc.) to prevent metal dust from getting into speaker or cabinet.

If these don't work, then drill or cut screw head off and drive out old t-nut. This is last resort since it will result in a lot of metal filings.

If on the other hand you have "spun" the t-nuts, then Tom Loizeaux's method will work and you wont be using files, saws & drills inside of the enclosure. I can't emphasize enough the importance of not introducing metal shavings to the inside of the enclosure or anywhere around a horn mouth. Been there, done that.

In future, always use hollow ground screwdrivers or screwdriver bits when working with machine screws. In fact, use them anytime you work with screws. Toss those cheap screwdrivers, way more trouble than the few bucks you save.

Buy an electric screwdriver with a clutch (not a drill-driver) so that you don't over-tighten the screws and so that you can torque screws evenly when installing speakers or other components. Sears has such a screwdriver for about $25 and it includes hollow ground bits. Well worth the money if you are going to be doing a lot of this.

[mikebake]

Thanks guys. I made alot of progress getting the basement and workshop cleaned up (on Mothers Day!), so next the cabs come upstairs into the light of day so I can determine how to proceed. I think I'll make whatever effort I can not to have to create metal shavings....we'll see!!!!
Bill, those fasteners look like the ticket, thanks!!
MBB

[mikebake]

Originally posted by RedZCar
You don't say if they are Phillips head or slotted head screws. If they are Phillips head, get yourself an impact screwdriver, available from either a motorcycle shop or from Sears, about $12-$15. It is little money compared to the damage you could do using the wrong tool or wrong approach. Any metal filings or chips get into your v/c gap and you will regret it!

If slotted head, then use David F's method, but take great care in prepping area (masking tape, etc.) to prevent metal dust from getting into speaker or cabinet.

If these don't work, then drill or cut screw head off and drive out old t-nut. This is last resort since it will result in a lot of metal filings.

If on the other hand you have "spun" the t-nuts, then Tom Loizeaux's method will work and you wont be using files, saws & drills inside of the enclosure. I can't emphasize enough the importance of not introducing metal shavings to the inside of the enclosure or anywhere around a horn mouth. Been there, done that.

In future, always use hollow ground screwdrivers or screwdriver bits when working with machine screws. In fact, use them anytime you work with screws. Toss those cheap screwdrivers, way more trouble than the few bucks you save.

Buy an electric screwdriver with a clutch (not a drill-driver) so that you don't over-tighten the screws and so that you can torque screws evenly when installing speakers or other components. Sears has such a screwdriver for about $25 and it includes hollow ground bits. Well worth the money if you are going to be doing a lot of this.

Phillips. I used a decent electric screwdriver; my own fault for buggering them up.
MBB

[HenryW]

Originally posted by mikebake
Phillips. I used a decent electric screwdriver; my own fault for buggering them up.
MBB

Rule number 1 - never, ever admit to being at fault.

Blame the cat, the dog or alcohol, but surely it wasn't your fault...

[mikebake]

Originally posted by HenryW
Rule number 1 - never, ever admit to being at fault.

Blame the cat, the dog or alcohol, but surely it wasn't your fault...

HAAA!! Well, in retrospect, I've probably been removing/installing woofers in and out of these cabs too many times over the last two years; swapping drivers, making repairs, changing crossovers, swapping horns in and out.
Once, I had them outside at work on tripods (yes, I opened them up to install the cups for the tripods, too) blasting away, and the wind blew one over. I even had the tripod tied off to a building; the (overly) thin metal on the (crappy Parts Express el-cheapo tripod model) buckled and then ripped through, The speaker slammed into a handrail, bounced, and then dropped four feet face first onto asphalt. Was still playing fine when I lifted it up, no apparent damage. Quick look inside (another removal).
Anyway, guess I didn't keep an eye on the condition of the screw heads until too late. The saga continues!!!