BMC & BL printing plates

[Mark1Peachey]

Found these in a job lot of car spares and thought someone could shed more light on when or what they may have been used for ? They are only about 5"x 3" but pretty cool I reckon. I love the old adverts for the BL range, who could resist an 1100 when it could do 0-50 in 14.7 seconds !!

[pad4]

offset lithography plates, they usually wrap round a drum which spins round whilst paper is fed past the drum , plates pick up ink then print onto paper

almost certain thats what they are

pad

[Smiffy]

There not lithography plates.
Heidelberg or Gallus.

[pad4]

Are both Heidleburg and gallus machines from the 50's 60's & 70's based on the rotating drum principal with stock feeders (either roll or sheet)

Which is technically offset printing from what i can remember - Maybe not but its still interesting, you dont see stuff like that anymore

Pad

[Smiffy]

Seeing a Heidleburg working, is a experience in it's self they are a fantastic piece of kit. One of the blokes I served my time with, had one in his garage. When he retired he offered it to me, just wish I'd had the room.

Yes most printing presses work on the cylinder system, Heidleburg and Gallus's both feed the paper in on a drum and the plates are on a flat bed. This type of printing isn't Litho, it's Letterpress.

If your ever in the lake district, there is/was a print museum in Cockermouth (about half way down the main street, same side of the road as the brewery). They have a working example, thats if it's still there.

[pad4]

Interesting - Probably worth going having a look, they always are these old machines before they get lobbed out, I used to be a type setter int good old days before apple macs and we had this huge bellows camera on rails for processing the artwork - all good fun , when the company went bust they just burnt the wood and leather bellows and weighed in the steel work



Pad

[guru_1071]

here is a question 'you old guys ' will be able to answer

how did they make the master of the plates above?

was it paper art work, which was then photo'd and printed on the lead / zinc / pot metal and then etched to get the 3d effect

how long would those plates last as they look pretty soft, or is all the scratching just from them been thrown around when they where worthless?

[pad4]

i used to make bronze masters using acid etch, typeset originals, photographed onto bromides, transfered to a cellulose carrier ( forget what bit this was) then i think we put on a light sensative emulsion that cured under uv light , the uncured bits washed off the bronze then you hit it with the acid .

we also used to hand engrave stuff using a pantograph machine

and hang on as ive got somet interesting to go with this thread

pad

[pad4]

Here you go

These are something i saved from about 1986



Hand drawn image (done with Rotring pens and lettraset)
Then a photo positive
then a photo negative

then the guff with the emulsion onto the brass (or bronze or whatever)

Then acid etched

This was something idid for the MCR as an award and If i remember correctly Mr flanagan got the award - although I still have the original one

Cool

Pad

[Smiffy]

As above acid etched and hand finished to remove any marks/hairs/crap from the dark room stages. Later they changed over to photosensitive nylon coated plates which where, etched in alcohol and yes you did feel quite pissed after making a batch of plates. Then water wash became the norm in the nineties, as the name implies these where etched with water then dipped in some rather nasty acid stuff i cant remember the name of to harden them off.

The above is a perfect example of the difference between Litho and Letterpress, you'll notice the Litho plate above is a right reading plate and the Letterpress plates are reversed.

[Mark1Peachey]

So when you were making the masters was it a gradual process using the acid or was it strong enough to remove all of the unwanted material in one go? Not sure of the material these are made from but it isn't that soft which did surprise me. Not sure if this one wasn't finished but it's not as pronounced as the others.

[Smiffy]

That looks like a 'Silk Screen' rather than a actual plate.

[mk1]

To get back to the crux of the original question. As part of the BMC / BL advertising drive they offered a whol;e range of these plates to main dealers to make up different newspaper adverts. There was a catalogue with all sorts of these in, you woul order the ones you wanted & they would arrive a few days later. These plates could then be either sent to the printers or used directly depending on the advert in question, there are a load here

http://mk1-performance-conversions.co.u ... blanks.htm

Mark F