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 > Specific Vintage Equipment > Vintage Test Gear and Workshop Equipment

Notices

Vintage Test Gear and Workshop Equipment For discussions about vintage test gear and workshop equipment such as coil winders.

Closed Thread
 
Thread Tools
Old 18th Nov 2022, 8:56 pm   #1
Chris55000
Nonode
 
Join Date: Aug 2007
Location: Walsall Wood, Aldridge, Walsall, UK.
Posts: 2,853
Default Marconi TF1041 Meter glass refixing, and large deflection when stood up

Can anybody recommend a suitable adhesive for fixing the front glass of the meter movement from a Marconi TF1041B valve voltmeter please?

As well as this, when I stand the instrument vertically with the knobs facing the front the pointer swings to about ⅓ f.s.d!

Has the movement been damaged in transit or is this normal for this instrument? – I was wondering if this is why Marconi provided a zero control that swings the meter over it's full f.s.d. range!

(I did see a picture of one of these on a Spanish website and it showed a similar deflection of the meter to what mine has when stood up vertically!)

I'll re–post in the appropriate thread if it looks like the movement will need attention from someone with better eyes than me, or a replacement movement!

Chris Williams
__________________
It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!

Last edited by Chris55000; 18th Nov 2022 at 9:25 pm.
Chris55000 is offline  
Old 19th Nov 2022, 10:01 am   #2
Station X
Moderator
 
Station X's Avatar
 
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
Posts: 21,192
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

Quote:
Originally Posted by Chris55000 View Post
Can anybody recommend a suitable adhesive for fixing the front glass of the meter movement from a Marconi TF1041B valve voltmeter please?

Chris Williams
Silicone sealant has worked fine for me.
__________________
Graham. Forum Moderator

Reach for your meter before you reach for your soldering iron.
Station X is offline  
Old 19th Nov 2022, 8:26 pm   #3
Ed_Dinning
Dekatron
 
Join Date: Jan 2004
Location: Newcastle upon Tyne, Tyne & Wear, UK.
Posts: 8,171
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

H Chris, I think a form of black Bostik was used in the day.

It sounds as if the meter is out of balance. If you look carefully at the movement you will seethe pointer attaches to a cruciform piece that is part of the movement. On the arms of this piece are tint springs, slotted on and often held in place with shellac.
Application of soldering iron heat allows the shellac to soften and the springs to be moved along the arm.
The movement can then be balanced in H&V panes in this manner.

HTH Ed
Ed_Dinning is online now  
Old 19th Nov 2022, 10:42 pm   #4
pmmunro
Octode
 
Join Date: Jul 2004
Location: Dundee, UK.
Posts: 1,797
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

https://www.go-araldite.com/products...l-2-x15ml-tube

PMM
pmmunro is offline  
Old 20th Nov 2022, 10:10 am   #5
Andrew Sinclair
Pentode
 
Join Date: Sep 2007
Location: Fareham, Hampshire, UK.
Posts: 103
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

I used araldite for the meter glass of one of the meters in a TF801 signal generator. After a couple of years the glass cracked, and I am certain the meter had not been knocked. I think it was due to stress in the meter movement when the signal generator was moved around. I have used Evo Stick ever since as it allows some "give." Silicone sealant would do the same.

Andrew
Andrew Sinclair is offline  
Old 20th Nov 2022, 2:30 pm   #6
Dickie
Octode
 
Join Date: Sep 2004
Location: St. Albans, Hertfordshire, UK.
Posts: 1,477
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

Quote:
Originally Posted by Ed_Dinning View Post

It sounds as if the meter is out of balance. If you look carefully at the movement you will seethe pointer attaches to a cruciform piece that is part of the movement. On the arms of this piece are tint springs, slotted on and often held in place with shellac.
Application of soldering iron heat allows the shellac to soften and the springs to be moved along the arm.
The movement can then be balanced in H&V panes in this manner.

HTH Ed

It certainly sounds like it. If the needle has a different deflection depending on its orientation it must be so. But that does beg the question of how it got unbalanced. It was presumably OK when it left the factory, so what's happened to it? Has it suffered some severe mechanical trauma, have bits fallen off, or what?
__________________
Regards,

Richard, BVWS member
Dickie is offline  
Old 21st Nov 2022, 1:47 am   #7
Chris55000
Nonode
 
Join Date: Aug 2007
Location: Walsall Wood, Aldridge, Walsall, UK.
Posts: 2,853
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

Unfortunately I can't tell, as it was a "sold as seen" purchase, however there's certainly no signs on the case to suggest it has been dropped, no dents, paint/enamel chipped off, etc!

I bought it because it came complete with probes and leads, all complete as in Marconi's book!

If it is possible to rebalance the meter as Ed Dinning suggests, I might pm him and ask him how much he'll charge me for sticking the glass back and having a go for me – the "common zero control" swung the pointer over so the meter certainly isn't o/c!

Chris Williams
__________________
It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!
Chris55000 is offline  
Old 21st Nov 2022, 3:33 pm   #8
Silicon
Nonode
 
Join Date: Jun 2007
Location: Coulsdon, London, UK.
Posts: 2,152
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

I recently glued a glass to a vintage bakelite meter housing.

The original adhesive seemed to be a brittle black material like shellac.

I wanted some flexibility in the bond and the option of removing it if the glass broke.

I used a clear 'hybrid' adhesive/sealant which is similar to silicon sealant but is over-paintable and does not contain acetic acid. I originally bought a cartridge of this adhesive for caulking & property maintenance.

Removing the unwanted adhesive that had been squeezed out onto the front of the glass had to be done after it had set. This was difficult. The temptation is to use a sharp metal tool but this could scratch the glass. I used some hard plastic.
Silicon is offline  
Old 21st Nov 2022, 5:54 pm   #9
MotorBikeLes
Nonode
 
Join Date: Dec 2012
Location: Kirk Michael, Isle of Man
Posts: 2,346
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

Chris, I used to have a 1041C, excellent unit. However, never had a 1041B, but I don't recall the 1041C as being intended to sit any way other than upright. I have a GEC/SEI bench top meter, similar spec to AVO 8, and like the AVO is clearly intended to sit down or stand up, so it must be fully balanced in both planes.
Is the 1041B INTENDED to lie down? If not, you may be chasing a non-fault.
Perhaps somebody else with one would comment.
Les.
MotorBikeLes is offline  
Old 21st Nov 2022, 9:38 pm   #10
Chris55000
Nonode
 
Join Date: Aug 2007
Location: Walsall Wood, Aldridge, Walsall, UK.
Posts: 2,853
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

Evening Les!

I'll have another read of the bookwork and make sure – sometimes the makers state if the instrument has to be used in a particular position or not!

Chris Williams
__________________
It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!
Chris55000 is offline  
Old 25th Nov 2022, 2:58 pm   #11
Outposter30
Triode
 
Join Date: Oct 2020
Location: Calgary, Alberta, Canada.
Posts: 22
Default Re: Marconi TF1041 Meter glass refixing, and large deflection when stood up

There are a couple of very small spiral coil weights on the meter pivot movement, and if one or both are missing, the meter movement is not balanced and will self adjust to the new balance point...

I found this out the hard way, but luckily for me, the spiral coil was still inside the sealed meter and I managed to find it and re-attach it to the tiny metal "arm" where it is normally attached.

I used a very very small drop of super glue to fix the coil/weight and it's fine now...

Good luck with your 1041B...I love mine...!!!

73...Jordan VE6ZT
Outposter30 is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 10:25 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.