Frequently asked questions

What is Thermofax?

Thermo-Fax or Thermofax is an old office technology dating back to the 1950s. The machines generated the masters used to print mimeograph copies but became obsolete with the widespread use of photocopiers. The machine houses an infra-red bulb that heats to a very high temperature and burns the image onto a plastic coated mesh.

What sort of imagery is suitable?

The thermofax process is particularly good for reproducing fine lines, text and marks. These are just a few starting points for generating your own images:

  1. Written or printed words such as your own handwriting, computer printed text, postcards, letters, recipes, certificates, maps, school reports, etc.
  2. Graphic marks made with tools, pens or brushes – anything from fine lines to more substantial marks. Try reducing or enlarging the marks to generate interesting images at different scales.
  3. Sketches and doodles, eg a charcoal life drawing, a pen and ink sketch or your child’s latest artwork.
  4. Rubbings of textured surfaces, eg bark, Indian print blocks or even a pile of threads.
  5. Photocopies of items like grasses, seedheads, feathers, threads, rice, salt, seaweed or lentils.
  6. Prints made with the cut surface of fruits and vegetables or bubble wrap.
  7. Photographs may be suitable but will need some digital manipulation as thermofax machines cannot handle shades of grey. You could try using some of the tools available in photo editing programs such as Adobe Photoshop like Levels, Curves, Threshold or filters such as Half Tone or Sketch to create interesting images. It is usually a good idea to ‘cut away’ the background as well to avoid rectangles edges. If you don’t have access to a photo-editing program you could try tracing the key elements of a photograph to create a slightly abstracted ‘sketch’.

Copyright: if you wish to use artwork that you do not own, please make sure that it is copyright free or that you have permission to use it.

What do I need to do before I sending my image(s) for processing?

Please check that your image:

  1. is black and white (without shades of grey)
  2. is positive, ie the black lines / marks / text on your image are the parts that will print
  3. does not have large areas of SOLID BLACK as these will not process properly.

If you are sending digital images, please check that they are:

  1. high resolution - ideally 300dpi
  2. saved in a suitable format – high resolution JPEGs and PDFs are the most popular image formats but other commonly used formats may be suitable. We do not recommend Microsoft office files – especially doc / docx – as they do not display correctly if your version of Office is different from ours.

If you are sending image(s) by post they should be photocopied before sending (please do not send original artwork). Alternatively, you can send a laser print (please note we are unable to process inkjet prints). You can download an order form to send with your images.

Can you check my image(s) for suitability before I order?

You can upload image(s) on the contact us page before you order. We will email you to let you know whether they are suitable and suggest minor changes if necessary.

How do I send my image(s) to you?

If your image(s) are digital, you can upload them from your computer when you place your order on the custom screen page. You can also do this at the checkout stage.

If you are posting the image you can find our postal address on the contact us page or you can download an order form to send with your images.

Do I need any special equipment apart from the thermofax screen?

You will need a suitable squeegee. Standard silkscreen squeegees are too aggressive for use with a thermofax screen. You can order specially designed lightweight squeegees from us to use with your thermofax screen(s).

You will also need ink or other print media. If you are printing on textiles or paper we can recommend our ranges of inks which are very easy to use and give excellent results. You can also use other types of media – our Print Media guide is supplied with your screen or you can download it from this site (pdf).

You will need to prepare a suitable surface for printing. Our guide, How to Use your Thermofax Screen, will be supplied with your screen or you can download it from this site (pdf).

How long do thermofax screens last?

With care you will get many hundreds of prints from a thermofax screen. However, they do not last forever. The media you use, how often you use them (eg repeatedly for long sessions or sporadically) and how carefully they are washed and dried will all affect their longevity and eventually the screen will break down.