Where I worked the drawings were almost all on coated polyester film when I started there (up to A0). These were also photographed/scanned and positive 35mm film images were put into aperture cards for everyday viewing and printing. When networked computers became a normal desk top item the aperture cards were all scanned as tiff images available over the network. As CAD became the normal method of producing designs and drawings the images were saved directly to the network. By the time I retired I had three monitors on my desk. For some work I did I needed one for looking at drawings, one for a spreadsheet and one for the program I was working on to produce my work output. Without three monitors the paperless office was always going to be impossible.

I suspect the future will be all digital.

I still drew up full sized layouts on polyester film (using coloured marker pens) for pipe fabrications but getting the polyester film was getting harder by the time I retired. 1500mm wide film was the first to disappear.

Martin C

Edited By Martin Connelly on 18/04/2023 18:58:16

Whilst unable to advise personally. I would suggest something like the V&A Museum or icon may be able to help. Links below:-

V&A

ICON

Edited By V8Eng on 18/04/2023 19:14:21

Scanning is an attractive option BUT make sure that someone keeps the media/format up to date. If you'd done it 40 years ago on 5"floppies you be a bit stuck, and the floppies themselves would have degraded.

I just overlapped the last of the tracer ladies, who had fine draughting skills and some of whom became draffies.

Ammonia printers! It must be hard to find somewhere to print the old continuous sheets, never mind A0 or double elephant. By the time I retired the customers all wanted prints at A3 so they could use their office printers.

If photographing, there will be some distortion introduced (no lens is perfect). The distortion can potentially be corrected in image processing software (if it even matters for your end use).

This distortion was made clear to me when I tried to scan from 35mm film images of some engineering drawings. I used some raster to vector software to try to generate a usable CAD output, the results were unusable because every originally straight line on the original drawing had a slight curve on the film.

Some good suggestions above!

I remember we occasionally had to do changes some linen drawings, it was a nightmare especially if had already been modified. A lot of linen drawings were given to apprentices to trace and when they were signed off we used to wash the coating off in hot soapy water to make lovely soft dusters, anyone esle do that?

To answer JA's point regarding Ammonia, the drawings don't come into or any where near liquid Ammonia. UV Light passes through the drawing which is placed on top of a sensitised paper sheet, passed through a light chamber via rollers. The exposed paper is then fed through an Ammonia vapour chamber which 'Develops' the coating, the master being separated from the print before that operation. Yes Henry, we used the 'Dusters' for dusting off Pounce.

Regards Ian.

Above system called 'Diazo' printing.

Waste Ammonia from this system ideal for soaking Balsa wood for bending.

Edited By Circlip on 19/04/2023 10:21:09

As a Reprgraphic Technician I copied lots of different types of drawings in the 70’s and 80’s including the linen ones.

Some were put on film, 35mm, 70mm or Half Plate. Full size copies on paper or polyester were exposed on contact boxes and then processed. Cheap copies were made on paper or polyester on a Dyeline machine (Diazo process). A lot of work was done on a Statfile large format camera. An easel in front of the camera was swung horizontal and opened, the drawing was placed face down onto the glass and then the white plastic back of the easel was locked back in place. The easel was then swung back vertically for the photo to be taken. Illumination was by eight 2’ fluorescent tubes. The camera had 70mm and half plate roll film backs but could also take sheet film up to 12” x 10”.

The old original Blue prints (white line on a blue background) used to come through for copying from time to time. The were lovely looking drawings. The process ceased to be used long before I got into Reprographics in the mid 70’s. Many folks these days incorrectly call Dyeline prints (dark blueish purple line on a whiteish background) blue prints. We had a film studio ask us to produce a blue print for a James Bond Film once. After my boss laughed and said that process was long gone he did offer a modern solution. It looked nothing like a blue print but served the purpose. We made a full size negative of their drawing on polyester film then made a paper copy on our Dyeline machine. I still have a copy of it somewhere.

I've had to do this numerous times for old drawings and when it was inconvenient to transport them across the country to the company's drawing office (where we had a large format scanner) have used local branches of Hobs Repro.

I think we were paying a couple of pounds per A0 sheet, for High-Res Scans same day turnaround.

If you don't want the hassle and risk of transporting the drawings, then one of my clients has used Flo Smart Solutions in the past to come in and do on-site scanning of hundreds of large format documents in one go.

Once everything is digitised, it's worth considering an agreement to transfer the originals to a suitable archival collection which can store them in a controlled environment for preservation.

Ideally such an agreement would see your organisation retain ownership and/or access rights in perpetuity, or offer a take-back clause where if the archive was unable or unwilling to store them, they would be returned.

Edited By Jelly on 19/04/2023 12:06:29

Hi, about 20 years ago HP.com sold 4600 & 4670 scanners, both of which could be used in their holders or just on top of anything. The 4670 came with a transparent materials adapter (TMA) which you could scan negatives etc. Both of the scanners were really the same and worked in the same way, and the best thing about them was that you can scan large documents and stitch them together. Photo below shows my 4600 one out of its holder.

So I set up a drawing, which measure about 705mm wide by 505mm, with the base lines of the top two views, parallel to a piece of Conti board as an index for my scanner.

I then took three scans across the drawing, which overlapped slightly, then turned the drawing round 180 degrees and set it up again to the same two lines as before and took three more scans. Then turning the upside down ones around stitched them all together to make a drawing of the same size as the original, with the use of some software. Below is an A3 size copy of the finished document.

Doing it this way can be a little time consuming, especially if you what a really good clean drawing, as the tones are often different in each individual scan, depending on how dense the sections are of lines, and it can be a labour of love. The biggest one I've done was a little larger than an A0, and took 28 individual scans and quite a lot of cleaning up, as it was a copy from a tracing from the same period as the one above, but the process does work to an acceptable level.

Regards Nick.

Edited By Nicholas Farr on 20/04/2023 09:38:26

Most I've had to do Nick was 36 and 28 scans for drawings of a model Vulcan and yes a labour of hate. It's the masochistic streak in me. regularly 8 scans per side for some plans and 4 for some others and then the luxury (very infrequent) of a single. Wish I''d had AutoCad and Photoshop 50 years ago. Surprising how much muck is on old drawings and 'Over run' on line endings and the ability to zoom and erase without having to brush down a drawing.

Regards Ian