Another Mystery Tool

[Martin King 2Participant @martinking2]

Hi All,

Just going through last weeks auction items and found this oddity:

Comes with a couple of bundles of these copper coated rods which appear to be carbon with a small central hole all the way through.

All I can think of is some sort of carbon arc setup, looks highly dangerous if that is the case.

Help welcomed.

Cheers, Martin

[Martin King 2Participant @martinking2]

[Dave HalfordParticipant @davehalford22513]

Carbon arc brazing torch with cables that are too thin as usual.

Exciting to use though

[Paul RhodesParticipant @paulrhodes20292]

Martin your spot is correct. A carbon arc brazing unit. Bring the rods steadily closer till arc commences then commence heating/brazing. Unsophisticated perhaps but works well.

[Adam MaraParticipant @adammara]

I have an old XP welder, and it has similar carbon rods, which are for brazing rather than arc welding, never tried them though!

[Don CoxParticipant @doncox80133]

Good for giving a suntan, make sure that all exposed skin is kept to a minimum, obviously appropriate eye protection needed too.

[noel shelleyParticipant @noelshelley55608]

Keller of Norwich used to market. Noel.

[Howard LewisParticipant @howardlewis46836]

Definitely an arc brazing torch.

I've got one, not used all that often, Very hot so has to be kept moving, but handy when needed.

Bit if a knack to keeping the arc correct.

REALLY need to cover all bare skin, otherwise severe sun burn.

Howard

[Speedy Builder5Participant @speedybuilder5]

You can use them to increase the carbon content of mild steel thus making the contact area hardenable – but you also get surface "erosion".

[bernard towersParticipant @bernardtowers37738]

Im with you there Noel they were sold from Kellers of Norwich on Cattle Market Hill.

[Martin King 2Participant @martinking2]

Hi all,

Here are two more mystery items from the weekends car boot haul, probably from a school physics lab, not sure what they are.

They appear to be incomplete but I do not know what is absent:

Any info would most welcome!

Cheers, Martin

[DC31kParticipant @dc31k]

Last one is I think a moving coil galvanometer. Shine a light at the mirror and you can measure the angular deflection when a very small voltage is across the terminals. Connect it to a coil and plunge a magnet in and out.

[peak4Participant @peak4]

I'd agree with the galvanometer, and I think the second item is a vacuum pump missing its bell jar.

Similar to this one 
https://www.bonhams.com/auctions/26661/lot/57/

I remember replying to this article on The BBC last year with some more detailed info, but I must have deleted the email now.
https://www.bbc.co.uk/news/science-environment-59562636

Bill

 

Edited By peak4 on 09/08/2022 19:14:26

[Willem KotzeParticipant @willemkotze19252]

The last item is a galvanometer. Reflected light beam for indication amplification. Low friction. Google "Galvanometer".

Willie

[Martin King 2Participant @martinking2]

Hi Peak4

If a vacuum pump would there have been a bell jar on the platform perhaps on a rubbers seal?

Martin

[peak4Participant @peak4]

Posted by Martin King 2 on 09/08/2022 19:12:09:

Hi Peak4

If a vacuum pump would there have been a bell jar on the platform perhaps on a rubbers seal?

Martin

or maybe a grease/leather seal, I'm not sure.

See my amended earlier reply too
https://www.bbc.co.uk/news/science-environment-59562636

Also include Ballistic, in your Galvanometer searches.

Bill

 

Edited By peak4 on 09/08/2022 19:20:52

[BazyleParticipant @bazyle]

Melted wax was also used as a seal. Used for suffocating butterflies or introducing something to kill them in the more elaborate ones.

[SillyOldDufferModerator @sillyoldduffer]

Agree bell-jar and vacuum pump. Nice find! I expect the pump seals are leather and will need to be replaced. Plastic might work. You can still buy bell-jars, try ebay etc.

The glass bell was probably sealed with Vaseline rather than hot wax because wax was used for more permanent seals. The four experiments I remember showed:

• air is necessary to transmit sound. (A clockwork bell gradually went quiet as the air was pumped out even though the clapper is seen to be still working).
• air is necessary to combustion. (A lit candle goes out when the air is removed)
• air is necessary to life. (A mouse dies when the air is pumped out.)
• alcohol boils when the pressure is reduced even though the temperature doesn't change.

Dave

[Martin King 2Participant @martinking2]

Hi All.

Many thanks for the info on these items.

The vacuum pump is now on its way to a French Instrument collector after a huge amount of interest on EBay.

Cheers, Martin

[Martin KyteParticipant @martinkyte99762]

I would have said that the last one was a ballistic galvonometer. The max angle of deflection being proportional to the total charge passed.

regards Martin

[Andrew TinsleyParticipant @andrewtinsley63637]

Hello,

Anyone know where you can get the copper coated carbon electrodes from. I have only a couple left. I assume Kellers are no longer!

Andrew.

[Martin King 2Participant @martinking2]

Hi All,

Yesterdays haul at Shepton Mallet included a stunning cased UNIMAT SL with power traverse and loads of accessories including three of these boxed components that I have never seen before, marked in different sizes?

Small part is bronze with thread to the end.

Any thoughts please?

Cheers, Martin

[Martin KyteParticipant @martinkyte99762]

Judging by the country of origin it's probably upside down.

Rather more seriously looks like a roller box tool maybe?

regards Martin

[Ex contributorParticipant @mgnbuk]

Any thoughts please?

Part of the Unimat SL screwcutting kit – see this video

This video shows the kit being fitted from scratch.

Nigel B.

Edited By mgnbuk on 15/08/2022 15:55:48

[Andrew TinsleyParticipant @andrewtinsley63637]

Cancel the above request! Just googled carbon arc rods and see there are plenty of sources. I just assumed that they were no longer used and hence not available. Should have checked first.

Andrew.

Sorry wrong thread! I can't delete it either.

Edited By Andrew Tinsley on 15/08/2022 16:21:36

[Author]

Posts