Microwave mains tranny - lams welded?

[Jon]

Hello, all.

I was just wondering if it's usually the case that the laminations of the
transformer in a microwave cooker are welded together. I'd like to re-use a
core or two if possible (by discarding the EHT secondary and winding a new,
vastly-lower voltage one at <80V), but obviously I can't if the laminiations
are welded together in all microwaves.

Cheers, Jon.

 

[Sam Goldwasser]

Hello, all.

I was just wondering if it's usually the case that the laminations of the
transformer in a microwave cooker are welded together. I'd like to re-use a
core or two if possible (by discarding the EHT secondary and winding a new,
vastly-lower voltage one at <80V), but obviously I can't if the laminiations
are welded together in all microwaves.

You can still do it, just more of a pain.

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[Jon]

Hi, Sam.

Is it just a case of splitting the welded lams apart? Could be
interesting... Is there any quick and easy way of doing this, or should I
just wait for a rainy Sunday : )? Doesn't welding the lams also effectively
short them together, thereby reducing the inductance of the core?

Cheers, Jon.

 

[Sam Goldwasser]

Is it just a case of splitting the welded lams apart? Could be
interesting... Is there any quick and easy way of doing this, or should I
just wait for a rainy Sunday : )? Doesn't welding the lams also effectively
short them together, thereby reducing the inductance of the core?

I've heard of people doing it both ways - splitting and rejoining the
core as well as just hacking off the HV winding and rewinding through
the intact core.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header is ignored.
To contact me, please use the feedback form on the S.E.R FAQ Web sites.

 

[Isaac Wingfield]

Hello, all.

I was just wondering if it's usually the case that the laminations of the
transformer in a microwave cooker are welded together. I'd like to re-use a
core or two if possible (by discarding the EHT secondary and winding a new,
vastly-lower voltage one at <80V), but obviously I can't if the laminiations
are welded together in all microwaves.

I had one that wasn't welded. I disassembled it and got a couple of
nifty degaussing coils for my trouble.

I suspect the welding is simply to prevent vibration -- buzzing.

Isaac

 

[Mr TUBEAMPS]

grined the welds off and thay should come
apart.

john