#1 Science Forum For Lab Technicians

Had to cut up about 300 pieces of Mg all exactly the same size for a reaction rate prac .
Got cunning .
Glued some scissors to a block of wood

That is awesomely clever! Well done! Now, you just have to make it adjustable and start producing them to sell. I'd happily pay for something like that.

Wow!!! What a great solution to the problem.

Merilyn1 wrote: ↑25 Oct 2019, 13:37 That is awesomely clever! Well done! Now, you just have to make it adjustable and start producing them to sell. I'd happily pay for something like that.

Thanks Merilyn , yeah I was going to make it adjustable but run out of time .
I bet a Chinabot has already seen this and gone into production ....but to help them out , what are typical size range that you would use ?

melsid , recon it would have other uses too , I know I've had to cut straws , pipe cleaners bits of chalk etc .

Usually 2 and 3 cm, sometimes 1cm. The other sizes aren't as common and usually for senior classes, eg 5cm and 10cm, so happy to do that manually.

Nice Work BigMack

Great idea!
I would have cleaned the oxidation off the surface of the magnesium first though......should be nice and shiny

DavidPeterson wrote: ↑20 Nov 2019, 08:07 Great idea!
I would have cleaned the oxidation off the surface of the magnesium first though......should be nice and shiny

Normally I do run it through some sand paper to clean it up David , but in the particular prac where it was used , we were getting unpredictable results and we put it down to inconsistent sanding .....IE some pieces were thinner than others and it was upsetting the results so we just used it as is ( oxidized) and it was more consistent.

Merilyn1 wrote: ↑25 Oct 2019, 13:37 I'd happily pay for something like that.

So would I!

Big mack, I have been frustrated enough in the past couple of years that I had started to design an automatic magnesium cutter.
The goal was that you'd just plug in what length you wanted and how many, and off it would go.
I got busy and forgot all about it!
Reckon it would be worth me spending some time on it these summer holidays?

Some screenshots of where I got up to:

wow Mr Cooper great idea

That looks amazing!

I love that MrC
That is flash

Hi all,
My HT is asking how long a full roll of magnesium ribbon is. I have no clue and I can't seem to find the answer anywhere so I thought I would come and ask all of yous before I tell him I don't know, and can't find, the answer.
Figure it is kind of a stupid question that I already know the answer to but worth the ask.
Thank you

Ask a few of the people that sell it?

You got me all curious!! I just found one on an American site that said a 25g roll is over 50 feet so more than 15 metres?

Or you could cut 10cm, weigh it, and calculate how long 25g would be from that. It won't be exact but close enough, I'm sure!

Can't give you an answer , but it may depend on the supplier .Some stuff I've used over the years is slightly different width and also thickness .
Also , not always a continuous roll . We had a lot at my last school that consisted of lots of short lengths that over lappped .Mind you that stuff was quite old and black .

RosalieL wrote: ↑04 Mar 2025, 09:55 Or you could cut 10cm, weigh it, and calculate how long 25g would be from that. It won't be exact but close enough, I'm sure!

Rosalie , I like your thinking there .

RosalieL wrote: ↑04 Mar 2025, 09:55 Or you could cut 10cm, weigh it, and calculate how long 25g would be from that. It won't be exact but close enough, I'm sure!

Very smart thinking, I might give this a go!

I was also thinking that it was 15ish metres but was unsure so I think you're right!

That's very true BigMack. I was thinking it would be hard to get an accurate and consistent length as they every pack seems to vary in what is actually in it.

LabbieSeth wrote: ↑04 Mar 2025, 11:00

RosalieL wrote: ↑04 Mar 2025, 09:55 Or you could cut 10cm, weigh it, and calculate how long 25g would be from that. It won't be exact but close enough, I'm sure!

Very smart thinking, I might give this a go!

I was also thinking that it was 15ish metres but was unsure so I think you're right!

That's very true BigMack. I was thinking it would be hard to get an accurate and consistent length as they every pack seems to vary in what is actually in it.

Afterthought - Given how light magnesium is, it may be easier to weigh a whole metre instead of 10cm. I'm interested to hear what your conclusion as I don't have the time and space to do it for myself right now!