If you'd have a close look at the 6th pic in #178, you'd recognize some strange thangs in about 14 holes. Those are slotted spring pins *afaik* and were used instead of threads. Unfortunately they project at about 1 mm from the surface. Even more unfortunately I didn't manage to extract any of them. Do you have any idea of how to? It is also impossible to jack them into until they are flush.
Best regards!
Best regards!
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Those look like helicoil inserts. Used when fasteners will be removed and screwed back into softer metal like aluminum lots of times, or to repair stripped threaded holes. I doubt that 14 of these strange thangs were stripped, most likely because they wanted to remove and replace whatever was being held in place by the fasteners.
No, these defintively aren't helicoils. Another strange thing with them is that I can't drive the same screws into them that I had unscrewed before. All these screws have metric threads, M2.6 and M3, resp.
If you compare my 5th and 6th pic in #178, you can see the screw heads prior of unscrewing and the empty holes with those thangs after it.
Best regards!
If you compare my 5th and 6th pic in #178, you can see the screw heads prior of unscrewing and the empty holes with those thangs after it.
Best regards!
Since this old thread is back to life...
I think my best true dumpster dive was 4 ballantyne t-25 amps and a couple of sleeves of NOS 7027As.
My most recent pre-dumpster intervention was 6 JBL 4301Bs from a bulding that was scheduled to be demolished. I gave a pair away and was able to put together a pair with matched drivers and sequential serial numbers from the remaining parts.
I think my best true dumpster dive was 4 ballantyne t-25 amps and a couple of sleeves of NOS 7027As.
My most recent pre-dumpster intervention was 6 JBL 4301Bs from a bulding that was scheduled to be demolished. I gave a pair away and was able to put together a pair with matched drivers and sequential serial numbers from the remaining parts.
I haven't the foggiest what those are in #178. If they ain't helicoils...don't know what they might use in Europe.
well ,how to say this in the nicest way possible ?
We as a species are nuts.
On the one hand we need to go "green" on the other we are throwing stuff away like there is no tomorrow .
I visit a scrapyard on a regular basis ,have dumpsterdived ,curbhunted for as long as I remember .
Taken found stuff I liked , left stuff I should have taken (hindsight is 20-20) .
Some stuff I found :
silver jewellery (that's just screws and stuff )
silver (big industrial fuses contain it )
tools (we are cleaning out granddad's shed)
working and nonworking electronics ( the comp. I am writing this with )
It is instructive ,teaches you to recognize stuff and how to take stuff apart,
you end up being able to use parts in project which you would otherwise not be able to get or afford .
And it is fun.
So keep recycling/upcycling and enjoy , regards F.
We as a species are nuts.
On the one hand we need to go "green" on the other we are throwing stuff away like there is no tomorrow .
I visit a scrapyard on a regular basis ,have dumpsterdived ,curbhunted for as long as I remember .
Taken found stuff I liked , left stuff I should have taken (hindsight is 20-20) .
Some stuff I found :
silver jewellery (that's just screws and stuff )
silver (big industrial fuses contain it )
tools (we are cleaning out granddad's shed)
working and nonworking electronics ( the comp. I am writing this with )
It is instructive ,teaches you to recognize stuff and how to take stuff apart,
you end up being able to use parts in project which you would otherwise not be able to get or afford .
And it is fun.
So keep recycling/upcycling and enjoy , regards F.
I'm quite convinced that these are slotted spring pins. But I really have no idea how they drew the screws into them 😕.
Best regards!
Hi I think I know these although the pics are not very clear. I think these are threaded bushings that are inserted with a special tool. I do not know the name except that techs call the tool a "Mollypliers" (which is the wrong name).
If I am right these are also used in sheet metal covers in machines. When the thread is damaged they need to be drilled out, then a larger diameter can be "pulled in".
If I am right these are also used in sheet metal covers in machines. When the thread is damaged they need to be drilled out, then a larger diameter can be "pulled in".
PEM nuts, they are a press fit. Despite the name, both male and female versions are available, as well as standoffs.
https://catalog.pemnet.com/category/pem-brand-self-clinching-and-broaching-fasteners
McMaster-Carr
PEM(R) Brand Fasteners Installation Demo – PennEngineering
https://catalog.pemnet.com/category/pem-brand-self-clinching-and-broaching-fasteners
McMaster-Carr
PEM(R) Brand Fasteners Installation Demo – PennEngineering
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Very late to ring in on this, but I absolutely agree. Most of the "true" tech companies (that dealt with hardware) are gone, there's probably 10% left of what there used to be, but I work in a special place that has a museum of equipment... And last year, they cleared out truckloads of stuff. dozens of scopes, power supplies, various lab equipment, prototypes, spare parts,etc.
I wish I had at least taken a picture of the 20 foot dumpster they got delivered for a week. So much good electronic stuff. I was not able to climb safely into the dumpster to get the Tek 5000 series mainframe + 1 plugin that I saw.
Oh well, I guess I'll wait another ten years...
Forgot about this thread.
Recently found a Hung Chang 5604 40MHz readout scope i the dumpster at work. Free fix, just filthy switches🙂
Recently found a Hung Chang 5604 40MHz readout scope i the dumpster at work. Free fix, just filthy switches🙂