Vintage MEM Electrics

[Vann]

I was wondering if anybody here is familiar with MEM electrical boxes, and can estimate the era of these two electrical boxes?

The first, a cast iron MEMREX, I'm considering fitting to my 1945 Wadkin PK dimension saw - which currently has a modern electrical isolator that looks out-of-place. Grace's Guide shows adverts of similar style MEM boxes from 1938 and 1946, so this should look appropriate.

The second, a pressed steel MEM, came fitted to my 1928 Preston 30" bandsaw. It has the same internals as the cast MEMREX, but is without doubt more modern. I don't know what was originally fitted to the bandsaw, but I'm curious to know when the electrics were upgraded. This time referring to Grace's Guide is no help - the latest illustration dates to 1964, but no sign of pressed steel boxes up to that time. I know the MEM switch was added prior to 1987 (as in 1987 it was moved from its original location and the orange PVC conduit was added).

Any help with dating these two switches - especially the second one - would be much appreciated.

Cheers, Vann.

 

[HOJ]

I cant be specific about dates of manufacture or introduction, but I was installing the Pressed steel MEM ones from the mid 1970's, (as an apprentice) I have 2 of the cast ones in my workshop, redundant but still in situ.

 

[Eric The Viking]

The cast one looks like 1940s. I remember black ones like that on my grandfather's machines in the 1960s (they were installed during the war, I think). The pressed steel one is 1970s onwards.

You used to see the cast ones sometimes as "fireman's switches" painted red on the outside of older retail premises. I never understood if they isolated the whole building, or just the illuminated signs on the outside.

 

[n0legs]

I concur with the the above replies.

:arrow: ETV. The fireman's switch is to isolate neon signs due to the step up transformer used for the high voltage the neons require.

 

[Vann]

Thanks guys. The cast one up to the 1960s. Pressed steel from 1970s. That helps date the work done on the bandsaw.

Cheers, Vann.

 

[lurker]

Whilst those examples look "clean", be aware old isolation boxes often have asbestos in them and by now its breaking down into breathable fibres

 

[Vann]

Whilst those examples look "clean", be aware old isolation boxes often have asbestos in them...

Ahh! Good point. I might vacuum it out - just to be sure. And while I'm at it I'll check out the cast iron MEM Startex box I picked up about the same time.

As an apprentice in the early 1970s, I remember packing white asbestos into a job (a gap around hot air ducting). Strange, because they were already aware of the dangers of blue asbestos at the time...

Arr... when we were young, we used to have asbestos sandwiches for lunch. And you try 'n tell the young people of today - they won't believe you... (said with a Yorkshire accent) :mrgreen:

Cheers, Vann.

 

[Wildman]

plenty of the cast ones in use in the 50's and pressed steel in the late 60's, as early 70's I pulled a load from a skip of a demolished factory when fitting out my own workshop with 3 phase.

 

[Vann]

Back in February, I was trying to find the age of some electrical components - including the ones that came on my 1928 Preston Woodworking Machinery (Canada) bandsaw.

I was wondering if anybody here is familiar with MEM electrical boxes, and can estimate the era of these two electrical boxes?

snip

The second, a pressed steel MEM, came fitted to my 1928 Preston 30" bandsaw. It has the same internals as the cast MEMREX, but is without doubt more modern. I don't know what was originally fitted to the bandsaw, but I'm curious to know when the electrics were upgraded. This time referring to Grace's Guide is no help - the latest illustration dates to 1964, but no sign of pressed steel boxes up to that time. I know the MEM switch was added prior to 1987 (as in 1987 it was moved from its original location and the orange PVC conduit was added).

Any help with dating these two switches - especially the second one - would be much appreciated.

Cheers, Vann.

You guys were very helpful, and the consensus was the the pressed steel boxes dated from late 1960s or early 1970s.

Just for the record, I found this photo in a 1963 edition of the Railways Bulletin Vol.12, No.1 1963, celebrating 2000 days injury free.

To the right of the picture is... my bandsaw !! (which was located in the Hutt Railway Workshops, Pattern Shop from 1929 to 1987).

Note that the electrical contactor and isolating switch are the replacement ones shown below. This means these were added prior to 1963 (and they look fairly new in the photograph).

So, for future reference, we can now conclude that MEM were using the pressed steel boxes from the early 1960s.

Cheers, Vann.