Chinese demagnetizers

[HectorLooi]

There had been a lot of criticism of the safety of Chinese demagnetizers in another thread. So I decided to look into how to improve on the design.

There was criticism about the AC cord not being secured and was able to be pushed into the box, so I installed a cable grip.

Then there was something that no one mentioned and that is there is no fuse in the entire circuit. So I added a 500mA fuse to the live wire coming in. I might reduce it to 200mA and see if it blows.

Someone mentioned that the circuit was charged all the time, as long as it was plugged in as there wasn't any power switch. So I added one.

And the biggest criticism about touching metal parts... I replaced the activation switch with an all plastic one.

So, did I miss out anything?

 

 

[praezis]

Well made.

45 minutes ago, HectorLooi said:

So, did I miss out anything?

Any metal connectors touchable from outside. You could use nylon screws instead.

Frank

[RichardHarris123]

What I don't understand is, if these items are unsafe, how are they available in countries with strick standards? 

I mean through the counties with strick standards, not directly from China. 

Edited January 3 by RichardHarris123

[oldhippy]

I would say it must be a government thing. 

[HectorLooi]

1 hour ago, RichardHarris123 said:

What I don't understand is, if these items are unsafe, how are they available in countries with strick standards? 

I mean through the counties with strick standards, not directly from China. 

Although many countries have strict regulations in place, enforcing them unfortunately requires too much resources. 

Governments can only adopt a "wait and see" approach, reacting only when something happens.

But China is progressing rapidly, learning and improving everyday.

About 25 years ago, we saw the first China made dental equipment. It was an absolute nightmare. It also had absolutely no primary or secondary fuses. When I gave feedback on their lack of electrical safety, their representative replied they have manufactured hundreds of thousands of such units and are used extensively in China, with no incidents. That was their attitude at that time.

I had to enlighten them on the concept of proactive safety and pointed them in the direction of attaining ISO 60601 certification.

They might not have achieved full ISO compliance yet, but have definitely come a long way.

[praezis]

2 hours ago, RichardHarris123 said:

What I don't understand is, if these items are unsafe, how are they available in countries with strick standards? 

The importer is liable that the imported (and now or later distributed) item is safe and meets the rules. He will be liable if a lethal accident happens by such unsafe items.

But importers (i.e. all individual buyers from china directly) just don‘t care and customs cannot examine each and every item.

Frank

Edited January 3 by praezis

[Neverenoughwatches]

39 minutes ago, HectorLooi said:

Governments can only adopt a "wait and see" approach, reacting only when something happens.

Thats pretty much the standard policy with the UK and I assume every country. The way of progression can be.... wait until enough people are injured or killed and then make a change... Look how long it took for cigarette advertising to be halted. Electical installation worked on much the same idea at one time...much more regulated and periodically updated these days . I'm just wondering how bad this device will be ?

Edited January 3 by Neverenoughwatches

[RichardHarris123]

2000 RPM, clay everywhere. 

[Neverenoughwatches]

1 hour ago, RichardHarris123 said:

2000 RPM, clay everywhere. 

Lol the speed is adjustable, (it's for my Patrick Swayze impersonation . But more to the point that the arbor and table are metal.....and that metal , water and electricity are a hair raising combo .  When have I ever atually used anything for its intended purpose Ricardo ? 

Erm....rarely

Edited January 3 by Neverenoughwatches

[oldhippy]

He bought a Chinese demagnetizer

Edited January 3 by oldhippy

[HectorLooi]

1 hour ago, Neverenoughwatches said:

Patrick Swayze impersonation .

If you use one of those, your impersonation might become more realistic than you can imagine.

[Neverenoughwatches]

14 minutes ago, HectorLooi said:

If you use one of those, your impersonation might become more realistic than you can imagine.

If i suddenly disappear in the next couple of weeks you know i made a mistake buying it

[RichardHarris123]

Just now, Neverenoughwatches said:

If i suddenly disappear in the next couple of weeks you know i made a mistake buying it

I don't think it's powerful enough to vapourise you. 

[Neverenoughwatches]

3 minutes ago, RichardHarris123 said:

I don't think it's powerful enough to vapourise you. 

Possibly if the electricity is passed through Krytonite first , I'll wear my lead lined spandex just in case

[RickTock]

14 hours ago, HectorLooi said:

There had been a lot of criticism of the safety of Chinese demagnetizers in another thread. So I decided to look into how to improve on the design.

There was criticism about the AC cord not being secured and was able to be pushed into the box, so I installed a cable grip.

Then there was something that no one mentioned and that is there is no fuse in the entire circuit. So I added a 500mA fuse to the live wire coming in. I might reduce it to 200mA and see if it blows.

Someone mentioned that the circuit was charged all the time, as long as it was plugged in as there wasn't any power switch. So I added one.

And the biggest criticism about touching metal parts... I replaced the activation switch with an all plastic one.

So, did I miss out anything?

 

 

Nice work! As soon as I hit 'Submit Reply' I'm going to unplug mine from the wall on put it on a power bar that is normally switched off. Nowhere near as thorough as what you've done, but good heavens(!) your post is eye opening!

[Neverenoughwatches]

On 1/3/2025 at 2:38 PM, HectorLooi said:

If you use one of those, your impersonation might become more realistic than you can imagine.

It arrived today and for 20 quid its...yeah its good. Has a little dc motor and plug transformer so i guess I wont get vapourised. Looks like it could be a very cheap little lapping machine. Quite unbelievably the table has no discernable wobble.