UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Hints, Tips and Solutions (Do NOT post requests for help here)

Notices

Hints, Tips and Solutions (Do NOT post requests for help here) If you have any useful general hints and tips for vintage technology repair and restoration, please share them here. PLEASE DO NOT POST REQUESTS FOR HELP HERE!

Closed Thread
 
Thread Tools
Old 7th Dec 2021, 7:55 am   #1
Radio1950
Hexode
 
Join Date: Apr 2017
Location: Buderim, Queensland, Australia.
Posts: 428
Default One Of The Best Hints I Ever Received

When I was a very young 15 yrs old "know it all", working on a Colchester Lathe making bolts for electrical air brakes, I was having trouble with starting a large threaded ring.
I forget exactly what it was.

The chief machinist, a wizened grey haired old guy, who seemed to be forever sharpening large drills and lathe bits, saw me, came over, and gave me this hint.

It is so simple that I hesitate to actually post it, but here goes ...

"To avoid 'cross threading' when you are assembling threaded bolts/screws/ rings etc, lay the parts together as best is possible, reverse rotate the threaded part gently until you feel or hear a click, then start rotating the part with correct rotation".

This works for bolts, screws, PK screws, collars etc whether LH or RH thread, and is especially useful for fine threads on large holding rings, eg for cameras, and even hand assembly N type coax connectors.
Works well when you do not want to start a new thread with PK screws in plastic etc.

I remember once when working on the rotary joint for a Thomson AS909 MSSR radar, there was a 350 mm or so diameter threaded ring, which was being difficult.
My mates were amazed that when I went over, I got it started in five seconds.

Anyway, this advice has served me well, and I use it every day almost unconsciously.
.

Last edited by Radio1950; 7th Dec 2021 at 7:57 am. Reason: Getting older day by day
Radio1950 is offline  
Old 7th Dec 2021, 8:28 am   #2
Stockden
Heptode
 
Join Date: Mar 2008
Location: Forest of Dean, Gloucestershire, UK.
Posts: 647
Default Re: One Of The Best Hints I Ever Received

Yes, I do that too. I learnt it from my father somewhere around 60 years ago.

Hugh
Stockden is offline  
Old 7th Dec 2021, 8:32 am   #3
Electronpusher0
Nonode
 
Join Date: Jun 2016
Location: Bognor Regis, West Sussex, UK.
Posts: 2,287
Default Re: One Of The Best Hints I Ever Received

I also do that, I have done it so long I cannot remember who told me the hint but it works.

Peter
Electronpusher0 is offline  
Old 7th Dec 2021, 8:39 am   #4
Craig Sawyers
Dekatron
 
Craig Sawyers's Avatar
 
Join Date: Nov 2010
Location: Oxford, UK.
Posts: 4,941
Default Re: One Of The Best Hints I Ever Received

My dad was a time-served engineering apprentice, back in the day that you signed 7 year indentures. I got a lot of tips from him, including the turning backwards until you feel the click trick.

The other one is if a nut is being difficult, turn it so it is tightening further and then try again.

Craig
__________________
Doomed for a certain term to walk the night
Craig Sawyers is offline  
Old 7th Dec 2021, 9:35 am   #5
stevehertz
Dekatron
 
stevehertz's Avatar
 
Join Date: Sep 2011
Location: Rugeley, Staffordshire, UK.
Posts: 8,809
Default Re: One Of The Best Hints I Ever Received

Quote:
Originally Posted by Craig Sawyers View Post
My dad was a time-served engineering apprentice, back in the day that you signed 7 year indentures. I got a lot of tips from him, including the turning backwards until you feel the click trick.

The other one is if a nut is being difficult, turn it so it is tightening further and then try again.

Craig
Yes, I think that works because there's probably a small amount of corrosion above the nut 'bonding' it to the bolt and stopping you undoing it, but below it it's clean and so if you can tighten the nut a fraction it breaks the ring of corrosion and to an extent eases undoing of the nut. Of course Plusgas always helps with stuck nuts and bolts.
__________________
A digital radio is the latest thing, but a vintage wireless is forever..
stevehertz is offline  
Old 7th Dec 2021, 9:35 am   #6
vidjoman
Dekatron
 
Join Date: Jun 2013
Location: East Sussex, UK.
Posts: 3,315
Default Re: One Of The Best Hints I Ever Received

I have always turned a screw or nut backwards to start it. Especially important screwing into plastic as if you were to start a new thread into already threaded plastic it will weaken or even strip the threaded hole. Use of powered screwdrivers is a definite no no.
Also important is to carefully note which screws you removed from an item in preparation for doing a repair. I've seen too many screws wrongly refitted, sometimes by careless repairmen and often by customers looking in case a wire had mysteriously dropped off.
Another important thing is to 'use your eyes' before starting a repair - look for burnt, damaged parts, discoloration of PCB's etc. It can lead you to the fault and reduce the time needed to find a possible cause of a fault.
vidjoman is offline  
Old 7th Dec 2021, 9:43 am   #7
stevehertz
Dekatron
 
stevehertz's Avatar
 
Join Date: Sep 2011
Location: Rugeley, Staffordshire, UK.
Posts: 8,809
Default Re: One Of The Best Hints I Ever Received

Quote:
Originally Posted by vidjoman View Post
I've seen too many screws wrongly refitted, sometimes by careless repairmen
I disagree, they usually leave half of them OFF.
__________________
A digital radio is the latest thing, but a vintage wireless is forever..
stevehertz is offline  
Old 7th Dec 2021, 9:47 am   #8
vidjoman
Dekatron
 
Join Date: Jun 2013
Location: East Sussex, UK.
Posts: 3,315
Default Re: One Of The Best Hints I Ever Received

Quote:
Originally Posted by stevehertz View Post
Quote:
Originally Posted by vidjoman View Post
I've seen too many screws wrongly refitted, sometimes by careless repairmen
I disagree, they usually leave half of them OFF.
I didn't mention the missing screws only the ones that had been re-fitted.
vidjoman is offline  
Old 7th Dec 2021, 11:01 am   #9
Nickthedentist
Dekatron
 
Nickthedentist's Avatar
 
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,820
Default Re: One Of The Best Hints I Ever Received

I did this in a long-established electrical shop recently, while trying a brass lampholder for size. The (very exerienced) chap behind the counter looked at me like I was an idiot and said "you're turning it the wrong way, mate"!
Nickthedentist is online now  
Old 7th Dec 2021, 11:09 am   #10
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 7,059
Default Re: One Of The Best Hints I Ever Received

Yes, it works well for lampholder lampshade rings and for jam-jar lids!
kalee20 is offline  
Old 7th Dec 2021, 11:15 am   #11
Lloyd 1985
Nonode
 
Lloyd 1985's Avatar
 
Join Date: Jun 2008
Location: Coningsby, Lincolnshire, UK.
Posts: 2,814
Default Re: One Of The Best Hints I Ever Received

Haha, yes! I do the reverse turn first, and no end of people always tell me I’m turning it the wrong way! They look even more confused when I tell them I did it on purpose! I don’t know where I learnt it, I think I worked it out myself once and just continue using it.

Regards
Lloyd
Lloyd 1985 is online now  
Old 7th Dec 2021, 12:13 pm   #12
stevehertz
Dekatron
 
stevehertz's Avatar
 
Join Date: Sep 2011
Location: Rugeley, Staffordshire, UK.
Posts: 8,809
Default Re: One Of The Best Hints I Ever Received

I think most people who use this method just figured it out themselves.
__________________
A digital radio is the latest thing, but a vintage wireless is forever..
stevehertz is offline  
Old 7th Dec 2021, 12:21 pm   #13
kalee20
Dekatron
 
Join Date: Feb 2007
Location: Lynton, N. Devon, UK.
Posts: 7,059
Default Re: One Of The Best Hints I Ever Received

Some care needs to be taken if it's a twin-start thread (as lots of jam-jar lids are, or even 3-start - but so are some precision threads, bicycle hub gear threads for instance) - you get two (or three) clicks very close together. Make sure you've got them all.
kalee20 is offline  
Old 7th Dec 2021, 3:45 pm   #14
Ted Kendall
Dekatron
 
Join Date: Jul 2008
Location: Kington, Herefordshire, UK.
Posts: 3,657
Default Re: One Of The Best Hints I Ever Received

You'd be amazed at the number of people I've come across who don't know this and should.
Ted Kendall is offline  
Old 7th Dec 2021, 5:00 pm   #15
initialsbb
Triode
 
initialsbb's Avatar
 
Join Date: Mar 2019
Location: Inverness, Scotland, UK.
Posts: 25
Default Re: One Of The Best Hints I Ever Received

This was one of the first things I learned as a bike mechanic - such a satisfying feeling when the bolt "finds" the thread! Good knowledge to pass on to the young 'uns
initialsbb is offline  
Old 7th Dec 2021, 7:39 pm   #16
broadgage
Nonode
 
Join Date: Jan 2010
Location: North Somerset, UK.
Posts: 2,129
Default Re: One Of The Best Hints I Ever Received

I learnt this in school metalwork lessons, a minor subject that proved far more useful than I expected.
Also VERY BASIC blacksmiths work in a proper coal forge.
broadgage is offline  
Old 7th Dec 2021, 9:25 pm   #17
duncanlowe
Nonode
 
Join Date: Jan 2016
Location: Stafford, Staffs. UK.
Posts: 2,529
Default Re: One Of The Best Hints I Ever Received

Another of those that does this, but has no idea where I learned it. But I will add that there are a few pendant lampholders that I've experienced where the shade holder ring refuses to help you when doing this, because the way they are moulded means that the thread is incomplete and the 'things' click even when completely out of alignment.

Freeing something tight by slightly tightening first works too.

Something I've found many times too. The protruding part of a threaded fixing gets corroded but the thread inside the nut is largely protected. So initial loosening is fine, but after just a tiny amount of loosening (sometimes less than a turn) things start to stiffen up. If this happens, DO NOT keep applying force to overcome it. Use the same technique as when cutting threads with a tap / die. Keep working backwards and forwards in partial turns, and add a lubricant. The corrosion gets taken off, without jamming the threads.
duncanlowe is offline  
Old 7th Dec 2021, 10:55 pm   #18
Richard_FM
Octode
 
Richard_FM's Avatar
 
Join Date: Sep 2017
Location: Stockport, Cheshire, UK.
Posts: 1,999
Default Re: One Of The Best Hints I Ever Received

I remember discovering this trick myself when trying to tighten something up.

F connectors can be tricky to tighten correctly from personal experience.

I've heard alloy engine blocks can be damaged by cross-threading so it's imported to make sure bolts are screwed correctly.
__________________
Hello IT: Have you Tried Turning It Off & On Again?
Richard_FM is offline  
Old 30th Dec 2021, 12:45 pm   #19
knobtwiddler
Octode
 
Join Date: Mar 2016
Location: London, UK.
Posts: 1,046
Default Re: One Of The Best Hints I Ever Received

The time to really observe this rule is when working with materials that easily gall when cross-threaded. A good example is stainless screws going into stainless threads. Always use some grease, always observe the reverve-twist-until-it-clicks method - and immediately go backwards if you feel unexpected resistance when screwing in. If a screw is in any way suspect, bin it without hesitation.

Edit - another tip: if you're using detachable driver bits and the screws aren't large, then take the handle off the driver bit and hold it in your fingers. This way you won't accidentally cross-thread it due to the extra torque afforded by the handle. Put all the screws partially in with the bit alone, and do the final tightening with the handle attached.
knobtwiddler is offline  
Old 30th Dec 2021, 12:52 pm   #20
Guest
Guest
 
Posts: n/a
Default Re: One Of The Best Hints I Ever Received

Some screws for plastic have two different height threads in a two start configuration, this may need another half turn backwards to get the right engagement. You can tell from which one is tighter/looser.
 
Closed Thread

Thread Tools



All times are GMT +1. The time now is 12:27 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.