Add a geiger counter to your tool kit.....

[bobtheterrible]

Hi All,

Not sure if this is the appropriate place to post this, but wanted to share. If this is already well known perhaps this post serves as a reminder.

I recently bought a joblot of old wristwatch movements from a seller on ebay - plenty to keep me happy for months. I opened one tin and "uh oh..." I didn't like the look of the dial. I quickly grabbed my geiger counter and found more than a few of the dials and hands were giving off alarming amounts of radiation. With some dials/hands, the radiation was making it through the tins/cases the movements were packaged within suggesting a flimsy acrylic crystal wouldn't provide much of a barrier.

If you are buying random movements/watches from unknown sources, I would strongly suggest investing in a geiger counter and a lead-lined box!

Bob

[Neverenoughwatches]

21 minutes ago, bobtheterrible said:

Hi All,

Not sure if this is the appropriate place to post this, but wanted to share. If this is already well known perhaps this post serves as a reminder.

I recently bought a joblot of old wristwatch movements from a seller on ebay - plenty to keep me happy for months. I opened one tin and "uh oh..." I didn't like the look of the dial. I quickly grabbed my geiger counter and found more than a few of the dials and hands were giving off alarming amounts of radiation. With some dials/hands, the radiation was making it through the tins/cases the movements were packaged within suggesting a flimsy acrylic crystal wouldn't provide much of a barrier.

If you are buying random movements/watches from unknown sources, I would strongly suggest investing in a geiger counter and a lead-lined box!

Bob

What was the radiation level reading mate. Can you post some photos to help describe what you are saying. Cheers.

[bobtheterrible]

I will need to look at this again in the morning but was getting 50-65 cpm at around 10cm distance. Have just done a reading of 70cpm at 1-2cm (0.046 mR/h). The dials are mostly those with painted numerals and the hands that I checked were lumed. Im keeping them out of the way till I can sort them out and store them safely.

Background is usually between 10-20 cpm (0.013 mR/h)

Edited October 6, 2022 by bobtheterrible

[Neverenoughwatches]

14 hours ago, bobtheterrible said:

I will need to look at this again in the morning but was getting 50-65 cpm at around 10cm distance. Have just done a reading of 70cpm at 1-2cm (0.046 mR/h). The dials are mostly those with painted numerals and the hands that I checked were lumed. Im keeping them out of the way till I can sort them out and store them safely.

Background is usually between 10-20 cpm (0.013 mR/h)

So around 4 times that of normal inside surroundings at approx 1 inch. What do we class as safe ?  Is an  outside full sun reading higher or lower than this ? 

[JohnR725]

 

On 10/6/2022 at 1:56 PM, bobtheterrible said:

If this is already well known perhaps this post serves as a reminder.

do a search it's been discussed before

On 10/6/2022 at 1:56 PM, bobtheterrible said:

I quickly grabbed my geiger counter

while I have a Geiger counter I don't recall that's on the normal watchmakers tool list?

On 10/6/2022 at 1:56 PM, bobtheterrible said:

With some dials/hands, the radiation was making it through the tins/cases the movements were packaged within suggesting a flimsy acrylic crystal wouldn't provide much of a barrier.

If you are buying random movements/watches from unknown sources, I would strongly suggest investing in a geiger counter and a lead-lined box!

are you suggesting we destroy a sizable part of the vintage watches because the reality is radium is everywhere and watch repair anything vintage is probably going to have radium of some quantity.

No I'm not trying to belittle your discovery I'm just pointing out we've discussed it before. It really becomes a problem in a few have a Geiger counter and then you're aware of oh dear should I be concerned?

For instance I once did a Mickey Mouse watch for somebody and the person who brought it to me was an assistant of a radiologist. So I pointed out oh by the way those hands are radium. She returned to watch the Doctor who took out his Geiger counter and the watch was never seen again.

Oh definitely excited about watches whited to take up military timepiece collecting. The military more was definitely better. As Seattle is relatively close to the Canadian border the local watch and clock collectors oftentimes go to meetings in Canada. On two separate occasions I've heard from people when coming back got pulled over at the border. That's because they had the ships clock with radium hands. I don't know if the clock was confiscated or not I think there were more concerned about something else which the clock was not.

Do a search we discussed it before on the message board.

[bobtheterrible]

Hi All, not been on line for a while.

Quote

are you suggesting we destroy a sizable part of the vintage watches because the reality is radium is everywhere and watch repair anything vintage is probably going to have radium of some quantity.

Not at all! Just that it was a surprise for me as I wasn't expecting radium dials/hands in this purchase. Admittedly I could have looked harder at the listing but it wasn't on my radar to have to deal with such. Without taking a reading I would not have known for sure and would have been much more blasé with handling.

Direct exposure is not my main worry, rather inadvertent ingestion/inhalation of dust/paint through mishandling. Perhaps this is something that comes with more experience - I suspected at least one dial was radium but was surprised by some of the hands which I absolutely might have had a go at re-luming without much thought.

This is likely to be an over reaction on my behalf but Im happy to know what Im dealing with.

If this thread is just generating noise, I can ask the mods to remove it.

[JohnR725]

we have an interesting problem is radium a problem if you don't know about it?

Finding lots of things interesting I assembly Geiger counter, partial kit. So mine is in calibrated but I can tell by how fast the clicking sound is that that's probably not good. Like the bag of military clock hands you'll pick it up several feet away and up close it sounds well very bad.

But what about the cards of watch hands. Watch hands come on paper cards if they have radium strong radium that I actually burn the paper which you can see the burnt paper look see you can tell it's radium but what about the other handset haven't burnt the paper are they a problem?

So if you look up radium was discontinued a certain year so we should feel safe that there is no radium left except a vintage. But watchmakers hold on the stuff forever what about those cards of florescent colored hands they haven't burnt the paper yet does that mean there's safe?

As I said there's been a discussion somewhere else on the group there are sites that talk about this so it's hard to tell how big of a problem it is unless you have a Geiger counter then it's a problem. Because now you know you have a problem otherwise you live in happy bliss that you don't realize what's going on. So I was surprised that a sizable quantity of the hands I had our radioactive. I can't remember where I banished the cards a radioactive hands are no longer in the bench. Even one of the hand refinishing kits later generation ones have a wax and something that looks like it might go ahead and and I thought all of those were safe but I have one of those it's radium. I also actually have a radium and refinishing kits one of the material houses found one of their back stocks I purchased it because I thought it was nifty so it's an banished I think the attic the same places the hands are.

So yes it's an interesting problem radium no matter what isn't good for you. Purchasing new old stock hams that look brand-new but you can't tell when they were made a Geiger counter goes crazy well maybe that wasn't a good purchase after all

 

[Jack75]

There is a handy plug-in radiation monitor for the smartphone with Apple and Android Apps. It plugs into the audio port and for my Android system it compares well with my Japanese Geiger counter. eBay list several versions all from CN.

Radium hand in watches are harmless - the alpha particles are stopped by the crystal and gamma radiation that escapes is nothing compared to the cosmic radiation dose received during a single trans-atlantic flight. Bare radium hands should be treated with care to avoid ingestion via nose or mouth. But if stored in a metal or plastic box they are also pretty harmless.

There is good evidence that small doses of ionizing radiation (gamma rays) could be beneficial as it is supposed that they stimulate the immune system. In my radiation work I took a sizeable dose spread over many years and now at 85 never suffer from colds, flu or Covid.