Repairing screw posts

Fatdog

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May 3, 2009
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This seems to be a problem that boombox collectors will experience at least once. Here is some advice for three different situations. Thanks to Superduper and SINISTER.

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To repair stripped threads:

One method is filling the hole with super glue or an epoxy that will completely harden. Drill a small pilot hole and then rethread.


To rebuild a missing screw post:

Use brass tubing that has an inner diameter the same as the outside diameter of the original post. Be sure to trim the length of the brass tubing as close to the original post. Fill the tubing all the way to the rim with J.B. Weld or something comparable. Make sure you get all the bubbles out when you fill it. Also, make sure you seal the bottom of the tubing as the filler may leak out the bottom if not blocked. Once completely hardened, the new post can be drilled for the screw.


To repair broken / snapped posts:

For broken posts, use liquid acrylic solvent available at any TAP plastic store. You use it in conjunction with a plastic bottle and needle syringe, also available there. It melts the plastic (literally) and welds the peices together. The resulting repair is as strong as the original because there is no foreign material. Once properly cured (evaporated), the break is literally fused together. The only thing is that you have to have all the peices because this is not a filler type glue, rather a solvent to weld peices together. If a peice is missing, it will always be missing although it is possile to fuse the available peices and when cured to full strength, the void is then filled with an appropriate plastic filler prior to painting, if necessary.
 

DocP

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Jan 25, 2012
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Great post ....tiny update ;-)
...an extremely durable repair of a stripped screw hole can be accomplished using a threaded metallic insert (most cell phones have them nowadays). So it becomes a metal (screw) against metal (threaded insert) union. What you'd be doing essentially is using a dremel drill to slightly widen the bore of the post so that you can epoxy in an

http://www.yardleyproducts.com/

If you are rebuilding a post....use a solid brass cylindrical profile with an internal thread threaded into the metal for your screw....
 

Mark GF-575

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Apr 26, 2012
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Just thought i'd add to this with my experience, I snapped three screw posts opening up my GF-575 and was very surprised how perished the plastic gets inside the units. Anyway I used epoxy resin to sort them out but now I would only open a 'box if I REALLY needed to and not to look just to see what's inside.
 

baddboybill

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Jul 14, 2009
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Mark GF-575 said:
Just thought i'd add to this with my experience, I snapped three screw posts opening up my GF-575 and was very surprised how perished the plastic gets inside the units. Anyway I used epoxy resin to sort them out but now I would only open a 'box if I REALLY needed to and not to look just to see what's inside.
Just a bit of FYI.........Opening every box is essential to clean up inside. As these 30 year old boomers have collected so much dirt/dust over years... This is bad for electronics because it will cause overheating and damage components. The only time it's unnecessary is if its a members box and it had already been cleaned ;-)


Bad Boy Bill
 

Reli

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Dec 24, 2010
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What if the broken half is missing? Would you break off the remaining half, and start from scratch? Or just build it up?
 

Mark GF-575

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Apr 26, 2012
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baddboybill said:
Mark GF-575 said:
Just thought i'd add to this with my experience, I snapped three screw posts opening up my GF-575 and was very surprised how perished the plastic gets inside the units. Anyway I used epoxy resin to sort them out but now I would only open a 'box if I REALLY needed to and not to look just to see what's inside.
Just a bit of FYI.........Opening every box is essential to clean up inside. As these 30 year old boomers have collected so much dirt/dust over years... This is bad for electronics because it will cause overheating and damage components. The only time it's unnecessary is if its a members box and it had already been cleaned ;-)


Bad Boy Bill
That's what I was doing, don't know why I didn't say but you know what I mean. :blush:
 

Northerner

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Apr 16, 2012
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If you're UK based I've just found that standard copper plumbing pipe (available in short lengths from any good builders merchant, I got mine in a half metre length) which is strong but easy to cut and bend, and Davids Isopon P40 glass fibre filler (£7 delivered and super fast from eBay seller gbaccessories!) works an absolute treat for refabricating missing screwposts :-D Just cut the pipe to slide over whatever is remaining of the existing post then glue in place with the filler and pack firmly the rest of the pipe with the same filler. Make sure you pack it tightly to make sure there are no air gaps though...the glass fibre makes it a little tricky to handle but its what gives the filler its strength. Once set you can file it neat then drill it using a drillbit narrower than the screw and jobs a goodun :yes: I was pretty impressed with how strong a fix it gives.
 

Northerner

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Apr 16, 2012
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Oh hang on...there's no pics of the screwposts on that one. Musta been on the S2G thread instead but seems to be down at the mo. I'll see if I've got some pics :)
 

Northerner

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Apr 16, 2012
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No not at all...the fibre glass stuff is super sticky but doesn't react with the casing at all. I did at least 6 on this box with no ill effects. I repainted the top of the box but the front, which has all the screwposts is untouched :)
 

Line Out

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Jul 16, 2012
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If inside of that brass tubing would be covered with a thin layer of some kind of "anti-seize", for example, a white lithium grease or thick silicone grease, one could remove the tubing after the process. Maybe a basic car wax would also work. At least it works with fiberglass (polyester resin)...