Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Med, I got 2 x 26-159-16 and 2 x 26-190-16 I'm never going to use.

They are yours if you want them.

If only you had chimed in sooner. The order I placed earlier is already prepping to ship and can't be cancelled. Oh well. 

[med6753]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same. 

[TERRA Operative]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same. 

Same, I don't use a lot, just 'enough' so I don't get stuck or galled nuts.
I periodically check the wheel nut torque and have never found one had loosened off.

[mansaxel]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same. 

Same, I don't use a lot, just 'enough' so I don't get stuck or galled nuts.
I periodically check the wheel nut torque and have never found one had loosened off.

The set of assumptions under which torque specifications are given among others most often includes "lightly lubricated threads". It also supposes that surfaces like tapers are reasonably clean and not overly friction-prone. The easier a thread runs, the more torque goes into actual hold-down force, and it is the elastic tension of the stretched (but not too much stretched) screw that presses together and increases friction between the parts and makes for a solid-acting joint.

The composition of most antiseize compounds includes lubricants, so, to this amateur with limited consequence comprehension, adding antiseize to threads makes for a better torqued joint than with dry threads. Practical experience (of course limited by sample size et c) supports this; inasmuch as I've never lost a wheel or a screw/nut that was torqued to spec under the influence of antiseize. Au contraire: when I loosen wheelscrews that have been goo'ed they're uniformly easy to loosen, and have sat a complete season (as has been mentioned, we swap to studded tires for winter here) without incident.

It is important to take the materials involved into consideration. A MgAl alloy wheel, for instance, will not appreciate copper anti-seize. There are Al formulæ  available for this situation, and they perform equally well without making an electrochemical mess. This of course is extra acute since there's NaCl spread on roads here in the winter. 

[Robert763]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same.

Lubricating threaded fastners causes excessive tightening, not under tightening. The torque is an indirect indication of the tension in the joimt. The calculation to derive the torque for a given tension includes a factor for friction. If you lubricate a bolt and tighten to a dry torque figure the forces in the bolt and joint will be too high.  So RTFM and use what the designer intended.

Note I'm from an aviation background where to save weight fastners are sized "just big enough" (factor of 1.5 or 2 times) so correct torque is much more important.
It's often not realised that one reason for high fastner loads is to improve fatigue life in joints subject to cyclic loads. This includes wheel studs connecting rod bolts etc. It is not to prevent loosening.

Edit Mansaxel types faster than I do   

[Neomys Sapiens]

I used to think, that it was bad with boat anchors... Yea right. It appears, that there is a urgent personal need for NASA optical table now. Resisting... yet. 

How many tons?

[DH7DN]

This channel opened my eyes 
I literally woke up 

 

[Andrew_Debbie]

Thinking about bidding on this Racal-Dana 2101 counter --> https://www.ebay.com/itm/224710802719?

Only Option 04C which is the base 'just a crystal'  frequency standard.   Missing an important button.    Manual is hard to find.

Will go for a stupid high price?


also watching this one --> https://www.ebay.co.uk/itm/284553818401

[AVGresponding]

This channel opened my eyes 
I literally woke up 

 

I could forgive them for the financial jiggery-pokery, after all, it's just rich people stealing money off us (they all do that anyway) and each other.

What infuriates me more than anything is the orbital and optical pollution. Land based astronomers have been under "siege" for the last decade already, due to the policy of replacing sodium street lighting with LED, which changes a narrow band of light pollution that is easily filtered, to a broad spectrum with many different peaks, that is much harder to compensate for.

Hopefully the FCC tell him to fuck off, but it's quite worrying that there isn't a more vocal opposition across all the affected agencies and institutions around the world. Maybe they just don't believe he can achieve the full net? If so, I believe they underestimate the power of bullshit to separate stupid people from their money, which is his speciality.

[AVGresponding]

The problem might not be with the IDC connectors themselves but the manufacturer using the incorrect wire gauge for the specific IDC connector. To me the wire slots in the unused connector positions look relatively large compared to the small size of the wire used. IDC connectors only cater for a small range of wire gauges and if the wire used is too small there won't be sufficient pressure in the wire slots to maintain a good gas-tight connection over time.

Check if there is a colour stripe on the side of the connector body: that would indicate the required wire gauge for that model of connector.  A plain white connector body usually indicates 24AWG sized contacts but the ribbon cable is probably only 26AWG or 28AWG.

Possibly, but even so, these IDC plugs feel very cheap and flimsy to me. That would also beg the question of why they would make such a basic error in an otherwise quite well designed and constructed item.

[DH7DN]

This channel opened my eyes 
I literally woke up 

 

I could forgive them for the financial jiggery-pokery, after all, it's just rich people stealing money off us (they all do that anyway) and each other.

What infuriates me more than anything is the orbital and optical pollution. Land based astronomers have been under "siege" for the last decade already, due to the policy of replacing sodium street lighting with LED, which changes a narrow band of light pollution that is easily filtered, to a broad spectrum with many different peaks, that is much harder to compensate for.

Hopefully the FCC tell him to fuck off, but it's quite worrying that there isn't a more vocal opposition across all the affected agencies and institutions around the world. Maybe they just don't believe he can achieve the full net? If so, I believe they underestimate the power of bullshit to separate stupid people from their money, which is his speciality.

You're absolutely right. The problems of light pollution and orbital pollution are becoming more and more of an issue. As long as it's not personal and it has no practical solutions, people won't care about it. On the other hand, there are many environmental "battlefields" (microplastics, air/water/soil pollution, deforestation) which are more urgent and needed a proper reaction already some decades ago.

For me personally, it's hard to blame a billionaire for destroying our world while it's us doing it every day. Like... don't forget that the space agencies have disposed rocket parts (and even a Plutonium RTG) in our oceans for at least 6 decades. Didn't SpaceX develop a reuseable rocket in order to address this particular problem?

I'm just concerned about the very quick progress in terms of a commercialization of space. If something goes wrong (e. g. Kessler syndrome), there will be no Elon Musk to clean up the mess. On the other hand, satellite technology has improved the lifes of people on earth (navigation, (weather) observation, communication, ...). Maybe we can find a proper balance between different interests. 

[Robert763]

TE Repair.
Had a look at the Delta Electronica SM1540D PSU. This 15V 40A PSU was an ebay purchase "parts or not working". Powered on it was dead. External fuses OK. Was previously remote controlled so set to manual - no change.
Opened it up and found F300 was missing. Someone has been in there. That is not great news. F300 is in the main high voltage (350V) DC line. Fitted a lower rated fuse (3.15A vis 6A). No change, still dead. No voltage on the LED DPM modules. They have a 5V regulator fed from 12V produced by a seperate mains fed SM PSU board. No utpt from this board.
I puled the board. This is not as hard as it looks. connections are all plugged or 0.125" spades. The boards then slide out. The PSU is a group of 3 bolted together.
Visual inspection showed a direty board and a flash mark around the transformer (potted) MOSFET and C508. There was also no HV DC. Input fuse was blown. It's a little yellow square Buss item. Looks more like a capacitor.
Checkes with the 8060A DMM showed no shorts and transfomery primary has continuity 
So what about the flash mark? I pulled C508 for a better view. The mark seemed to be under the capacitor. It's a 100pF 1kV ceramic across the switching MOSFET. Some kind of snubber. Checked OK on PEAK LCR. So put it on the Megger BM80 insulation tester. OK at 250V but broke down at 500V. Cleaned it up and it looks like it's tracked and flashed over between the leads. This is despite having little ceramic insulator disks on the leads. I cleaned the board and disks. Fitted a new 100pF 3kV ceramic and a 1/2A Picofuse.
Plugged it all back in and switched on. No bangs, displays lit up. Howerver Over Volt Protection LED is on an no output. OVP come on for various reasons.
Issue seems to be main switching MOSFETs are not being driven.
More work to do.....

[Specmaster]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same.

Lubricating threaded fastners causes excessive tightening, not under tightening. The torque is an indirect indication of the tension in the joimt. The calculation to derive the torque for a given tension includes a factor for friction. If you lubricate a bolt and tighten to a dry torque figure the forces in the bolt and joint will be too high.  So RTFM and use what the designer intended.

Note I'm from an aviation background where to save weight fastners are sized "just big enough" (factor of 1.5 or 2 times) so correct torque is much more important.
It's often not realised that one reason for high fastner loads is to improve fatigue life in joints subject to cyclic loads. This includes wheel studs connecting rod bolts etc. It is not to prevent loosening.

Edit Mansaxel types faster than I do   

Robert, you are correct, the threads on the wheel studs are always designed to ensure that the wheel motion has a tendency to tighten if anything rather than loosen the nuts.

[mansaxel]

Robert, you are correct, the threads on the wheel studs are always designed to ensure that the wheel motion has a tendency to tighten if anything rather than loosen the nuts.

I do not think that's what Robert wrote. That would imply a centre nut or similar; and left vs right threads depending on side of vehicle. Like bicycle pedals, which are exactly so; a thread that's concentric with the centre of rotation, and a thread cut so as to tighten in normal motion.

Scania trucks of the 60s and 70s were like so; one side of the chassis had left-hand threads, even for normal circular pattern screws and nuts; it's a number of screws protruding from the hub and nuts are then tightened on them. Thread is 7/8"x11 BSF, actually.



Today, almost no-one bothers with left threads. The tension from elastic screws is holding the joint, and since the screw is offset from the rotation centre, the incentive to work loose is not as strong.

[Specmaster]

Robert, you are correct, the threads on the wheel studs are always designed to ensure that the wheel motion has a tendency to tighten if anything rather than loosen the nuts.

I do not think that's what Robert wrote. That would imply a centre nut or similar; and left vs right threads depending on side of vehicle. Like bicycle pedals, which are exactly so; a thread that's concentric with the centre of rotation, and a thread cut so as to tighten in normal motion.

Scania trucks of the 60s and 70s were like so; one side of the chassis had left-hand threads, even for normal circular pattern screws and nuts; it's a number of screws protruding from the hub and nuts are then tightened on them. Thread is 7/8"x11 BSF, actually.



Today, almost no-one bothers with left threads. The tension from elastic screws is holding the joint, and since the screw is offset from the rotation centre, the incentive to work loose is not as strong.

Maybe right, I was going by the time I used to work on buses, and they always had left and right-handed threads on their wheel studs and were never tightened by torque wrenches. The used a nut spinner on a shaft with hole through the shaft, into which a bar somewhere around 4 to 5 ft was inserted, and then it just down to good old muscle power to tighten as hard as you could. In my 8 years of working there on about 170 buses and coaches, we never experienced a single case of wheel loss or any slackening of the wheel nuts and most of the buses were out every day from about 5:30AM to about 11:30PM pounding the roads in Essex.

[0culus]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same. 

Same, I don't use a lot, just 'enough' so I don't get stuck or galled nuts.
I periodically check the wheel nut torque and have never found one had loosened off.

The set of assumptions under which torque specifications are given among others most often includes "lightly lubricated threads". It also supposes that surfaces like tapers are reasonably clean and not overly friction-prone. The easier a thread runs, the more torque goes into actual hold-down force, and it is the elastic tension of the stretched (but not too much stretched) screw that presses together and increases friction between the parts and makes for a solid-acting joint.

The composition of most antiseize compounds includes lubricants, so, to this amateur with limited consequence comprehension, adding antiseize to threads makes for a better torqued joint than with dry threads. Practical experience (of course limited by sample size et c) supports this; inasmuch as I've never lost a wheel or a screw/nut that was torqued to spec under the influence of antiseize. Au contraire: when I loosen wheelscrews that have been goo'ed they're uniformly easy to loosen, and have sat a complete season (as has been mentioned, we swap to studded tires for winter here) without incident.

It is important to take the materials involved into consideration. A MgAl alloy wheel, for instance, will not appreciate copper anti-seize. There are Al formulæ  available for this situation, and they perform equally well without making an electrochemical mess. This of course is extra acute since there's NaCl spread on roads here in the winter.

As far as I can tell, anti-seize is a critical piece of car care in the rust belt. If you don't use it, well, RIP.

[med6753]

Dusty Dawg.




Cleaned up. I don't have a CRT bezel for this one. Plenty on Ebay.



There's still a crap load of sawdust behind the tubes. More later.

 

[Cerebus]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same.

It's one of those misnomers propograted by people who don't understand the difference between torque and bolt tension. If all you have is a torque figure then you should apply that torque under the lubrication conditions that torque is specified for. When one is tightening a bolt one is not aiming for a particular torque but for a particular  stress (i.e. preload) in the bolt - as this is hard to measure directly torque (or occasionally strain) is used as a substitute. The actual preload applied can vary as much as ±25%* if you're using a well defined tightening method, considerably more if you're just got a bald torque figure sans lubrication data. Of course the chances of someone bothering to provide one with a torque figure and lubrication conditions is scant - what's the point of doing a proper job documenting things when you can do a half-arsed one instead.

The claim that "putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued" is the opposite of the truth. If the fasteners are lubricated less of the work put into tightening the fastener will go into overcoming friction and more will go into generating preload - so lubricating a fastener for which you have a 'dry' torque figure will produce more preload than intended so they will be "over torqued".

*Source: Machinery's Handbook 28, p1432 et seq. ±35% for doing it by feel, ±25% using a torque wrench, ±15% using 'turn of nut'.

[factory]

Last of the items from the auction for tonight, hp 745A & home-made amplifier that uses bits from the 746A tomorrow.

hp 181A 181T oscilloscope (actually spectrum analyzer frame) with 1801A four channel input & 1825A delaying timebase plug-ins (no tunnel diodes in these), all rear feet present for a change.


This was sold as a 181A, the 181T is probably more useful if I end up with some SA plug-ins (didn't win the spares lot with some in).


David

We used to travel all over Western Australia with these as part of our kit-------always with the SA plugin.
It never was the "arm stretcher" that the 141 was!

I remember one with normal "CRO" plugins, but that was a "Depot queen", & never left.
It wasn't used much for general purpose "scoping", either -------pro Tektronix bias?

Dunno!

Yeah my right shoulder is complaining a bit today, was looking at the hp 745A AC calibrator last night, which is the same size as the 140/141 series and weighs about 65lb/29.3kg (ref. 1976 catalog).
Kind of glad I didn't win this lot now, with 182A, 182T, 180TR, 181TR and a bunch of SA plug-ins in various states of disrepair, these made £156 + fees.


I did however win a bunch of poor condition 140/141 series SA plug-ins, they either have bits missing or notes stating the fault(s), I suspect they were used as parts mules. That probably what I'll be using them for, except maybe the 8555A, labelled with a mainframe fuse blowing fault.

David

[mnementh]

On my car I used a bit of nickel anti-seize on the threads and tapers. Mainly to help prevent them scratching and galling the mating tapers on my $4000 rims.
The McGuard/TRD nuts I used have a cool feature where they have a 'floating' taper that can rotate on the nut, to further help prevent scratching and galling.

There are those who claim that putting anti-seize on wheel studs prevents you from properly torquing the lug nuts and they will essentially be under torqued. But I've done it for years and never had an issue. Turns out the mechanic I deal with does the same.

Lubricating threaded fastners causes excessive tightening, not under tightening. The torque is an indirect indication of the tension in the joimt. The calculation to derive the torque for a given tension includes a factor for friction. If you lubricate a bolt and tighten to a dry torque figure the forces in the bolt and joint will be too high.  So RTFM and use what the designer intended.

Note I'm from an aviation background where to save weight fastners are sized "just big enough" (factor of 1.5 or 2 times) so correct torque is much more important.
It's often not realised that one reason for high fastner loads is to improve fatigue life in joints subject to cyclic loads. This includes wheel studs connecting rod bolts etc. It is not to prevent loosening.

Edit Mansaxel types faster than I do   

1000xTHIS!

Even the most mundane applications have some pretty complex fastener specifications anymore; lugnuts are especially important depending on the the material of the rim, and failure to apply the correct technique and torque can cause cracking or galling of the rim, warp a rotor, or even cause premature axle bearing failure, especially in FWD vehicles.

RTFM is the order of the day for sure nowadays, when even a grandma's grocery-getter car like our Rav4 needs special tools for the cartridge oil filter.

Regarding rattle guns... yes, the new cordless ones are effing amazing; the advent of industrial brushless motors has finally made possible an electric motor armature with a ratio of torque to low rotational mass similar to an air motor, and with similar rotational "elasticity". Traditional big air-gun hammer/anvil designs finally work correctly, where electrics used to have to muddle through with dog/pintle clutch designs that just cannot generate as much "break-free" torque.

While I still own a 1" drive air impact (rated 1400 ft /lbs, but you need to feed it with ~20HP compressor and a 3/4 in hose to get that; talk about a air-waster ) from the farm days, these new electrics are effing amazing. It's just that for SOME applications (like big trucks and buses), we're still talking an order of magnitude more horsepower required, and portable electric just isn't reasonable. Yet.

In perspective: I have a 1/4" hex drive, as well as a 3/8" & 1/2" square drive Kobalt impact gun; these are rated 1800 in-lbs, 150 ft-lbs and 380 ft-lbs respectively. With proper shank/socket, any of these will whip the lugnuts off/on the Rav4. All of these have an electronic adjustable tightening torque-limiter. On lowest setting with the 3/8" and 1/2" drive models, this limits to ~40ft-lbs; this is perfect for the first round of torquing on most passenger vehicles, to be immediately followed by 2nd or final round with a proper torque wrench.

And all these 6S Li-Ion powered cordless guns come in at $99 everyday (they have a 650 ft-lb rated 1/2" drive model now for $199 with batt/charger) or around $50-75 a pop when bought in whatever kit LOWE's has on sale for Father's Day or Christmas...  *EDITED: I forgot I actually have 3 of them now...

I'll suggest that this is probably the biggest reason you'll see tire shops switching over to cordless rattle-guns; it's gotta be a lot less assache than fuck-knuckling a couple of torque-stick sockets (a one-piece socket with long shank that limits torque by dint of metal elasticity) and air zip-gun/hose all around the shop.

This has to hugely improve the efficiency of workflow in such a high-turnover environment, where the metrics aren't measured by the usual 1/10th, but by the 1/100th of an hour.

mnem
Adapt or die.

[mnementh]

Ugghhh.

The keyboard on my Lenovo laptop just kakked again; guess my ribbon-connector fix wasn't permanent. Good thing I had the BT keyboard I use for my Lenovo tablet to finish that long-winded post... 


That assache/cost (keyboard is integral with the top cover on this one; like the bonded LCD/digitizer, a concession to making it "thin"  ) on top of the cracked digitizer... It may be time to shop for something a little newer rather than repair.

mnem
*sigh*

[mnementh]

R E D   A L A R M ! ! ! !      May all the Ferengi be with me.   

I see now that scope on the top of pile trash... We are pretty soon to the black magic moment...   Those bastards...

Not too easy. They have implemented a four eyes principle where the stuff will be collected and disposed by an external company.   Not sure what to do. I will try to contact that company afterwards.   I can't risk to be fired because I wanted to save a scope.

Only you TEA brothers can understand me, this is such a sad story.   mnem can I use it?

Well... if it really is only a 4-eyes/2-man principle thing, you should still be able to get approval reasonably easily. If it's just nepotism guised as protocol, then you could have problems.

Of course you may use Sad Batman, my [img] stash is there for all of TEAnonymous to use, not just the agitating tinkerdwagon. 

mnem
 

[factory]

I had a quick look at the hp (hernia producer) 745A AC calibrator last night, it's fairly clean inside apart from some dust on the right hand side, this is probably due to the inadequate size of fan filter. 
All the dark gray blocks are transformers, should be six in total if I read the manual correctly.


Can't quite read all the info of the reference section, there should be three lines on the graph. 


There are a couple of suspect capacitors on the red board, I suspect these 69F caps are wet tants  , but quick web search reveals nothing. Peak ESR said they weren't shorted, but they will need replacing.


Underneath has the frequency reference & dividers in another compartment and bunch of amplifier transistors at the back, near the fan (early 745As have a heatsink fitted instead of the fan).



Not sure it left the hp factory with this mess hanging off the back of the mains input section. 
These resistors may explain why the fan is barely audible, or my hearing has got worse.


Time to give it a quick try, hp 34401A is giving strange & incorrect readings on all ranges, but the Wavetek DMM seems to give a more sensible result, frequency not verified but should be around 1.65kHz if the dial is correct.
Also the 10V range is borked, overload light comes on with no load.




David

[AVGresponding]

Can't quite read all the info of the reference section, there should be three lines on the graph. 

You could try taking photos in near-IR and near-UV, easily and cheaply done. It might show details that aren't visible/are swamped under normal lighting conditions.

Time to give it a quick try, hp 34401A is giving strange & incorrect readings on all ranges, but the Wavetek DMM seems to give a more sensible result, frequency not verified but should be around 1.65kHz if the dial is correct.
Also the 10V range is borked, overload light comes on with no load.




David

Maybe there's some harmonics present that shouldn't be there, that are confusing the 34401A but which the Wavetek doesn't see/doesn't care. Or a big-ass DC offset?   

Time to break out the Tek THS I'd say...

[med6753]

More of dusty dawg clean up.

For some reason the tube on the far left under the shield was missing (12AU7). That tube is solely for the calibrator. A mystery as to why it was missing. Not any longer. Each tube/transistor socket got a blast of deoxit.   

Left to do. Flip it on it's side and pull the bottom cover and clean that. Then initial resistance checks and power up.





Edit, I found the AWOL 12AU7 tube under the chassis.  Why and how did it get there?