Making Dial Gauge Faces

[oldnorton]

The image below is of the set of dummy gauges, plus one real pressure gauge, on my five inch model of 70013.

They looked quite reasonable when new, but now, two years later, the faces are a brown and sorry mess. They were laser printed onto white card and the boiler heat plus oil seeping in has cooked them!

Does anyone have any thoughts on how to print these tiny things onto a heat and oil resistant surface? Ideally it would be black enamel paint onto a white painted brass disc, but I cannot conceive of how to do that. Would laser print onto a thermally stable white plastic work? Or is there a way of making home transfers that can be applied to the white painted surface?

Has anyone done it themselves?

Norm

[uuu]

I was wondering the same thing myself, wanting to make a face for a small clock. So I did a bit of Googling, and came up with this guy, making custom dials for watches: watchcomplications.com/making-custom-dials/

His process seems to involve using a laser printer to make a waterslide decal, applying this to a painted surface, baking in the oven, then applying an acrylic coat. I've no idea if this would be durable in a pressure gauge, but he seems to have done quite a lot of experimentation with different approaches (for watches), so it's a start.

Wilf

[steamer5]

Hi Norm,
For my sins i get to look after signage at work. A while back i had to get pipe work content colour banding made for pipework at 70 ish degrees C. I talked to the guy I used & he said yep no problem, just have to use the right vinyl material. They have been in place for the best part of 2 years now & look pretty much as they did the day i put them on.
If you have a sign writer... read toady more likely a sign printer near by go & have a chat, they should be able to help. You may have to provide the sign graphics but they maybe able to do it for you as well, likely if they print 1 they will print you several at the same time given the size.

Cheers Kerrin

[coniston]

Hi Norm, you can certainly buy waterslide transfer paper for laser printers like this www.ebay.co.uk/itm/355158086579?hash=item52b11253b3:g:SwAAAOSwiyZlQ7dH&amdata=enc%3AAQAIAAAA8DvarSyIuNKtKkFrkmo3Mg0VIntDtvoL%2FkdxNt6xk%2FXtuxMRna18%2Baz7hZkx%2BnLI4lhpSF%2BFKM12si7hxNBsmIO6EZH2Xwgv9wxMl7S4X59zMlL%2F%2BkpN81S%2F05nKJbdf8yZ65Thdxy1SgbX3xM4qAq3EHRa%2Bp0dY5yUjnQ0cqLhktYfkE7csEkEntdT37durEjyLb0o2wv1JXGRn5tWY3v0tpF79nMVw3mSNJsHRTB9EOtLinXkJMOIuM%2FKQooH52N0AHxm9a%2FYae4eTKfWSEU%2BcdvjDPQI6GIYimC1jcc7L3o0UsOzdUYTsLj%2BQXr4ldA%3D%3D%7Ctkp%3ABk9SR4jhkdL6Yg

Not sure how translucent it would be but worth a try?

Chris

[ock]

Use pad printing, developed by the early clock and watch makers to produce dials. Your only difficulty may be to find white ennamel that is not heat effected.
YouTube has many articles on how to do it. For one or two dials the simplest equipment is sufficient
ie a gelatine pad with a compound table under the drilling machine and a hand operated squee-gee.
Photo engrave one, or more, brass cliche plates from your enlarged art work.
It is time consuming but gives a high class product
John

[chris vine]

I had never heard of Pad Printing. Looking it up it is clearly an very cunning process!

For the white paint, I have used white gloss enamel made for painting domestic radiators.
It seems to be fairly heat proof. However, one of the model suppliers enamels would probably be just as good or better.
An experiments suggests itself!!

Chris.

[brucevoelkerding]

The Pad Printing process is what we used at GE to print the Logos on top of regular Light Bulbs and Fluorescent Tubes. This Video - youtu.be/rnjm_cg4uDc - explains the Process and demonstrates how you could do it on a Drill Press like John mentions above. Note the Cliche Plate has the Image photo-etched into it. On a production Machine, a Pool of Ink is swiped over the Cliche Plate, leaving the Ink in the depression. The Image Depression is not deep, it looks more like a rough Surface. We would typically operate our production Units around 1 cycle per second.

As a side Note, the technical Term for the Silicone Rubber "Squeegee" is the "Tampon". That Term was even used in the German language Instructions received with the last Units we purchased. That might help you in future Searches.

[millman]

I like the idea of white radiator paint, I suppose the commercial gauges are silk screen printed. Kozo Hiraoka’s book on building the Heisler contains details of how he made his own pressure gauge and also a dead weight tester to calibrate the gauge, I have made the dead weight tester and it works surprisingly well, I have not plucked up the courage to try the pressure gauge though.

[chris vine]

The radiator paint is only a suggestion, but it has worked ok on the little mugs and tea can on Bongo. These sit on the little shelf on the backhead.
However, it is easy enough to test things like this. Paint a coin and leave it on top of the boiler for a few steam-ups...

Chris.

[ock]

Hello Norm,
Many of the engine builders used commercial pressure gauges
with ceramic dials, ie like a flat bread and butter plate, so they
did not discolour or ruckle up with the heat.
You can make up the discs with bone china slurry, after firing,
surface grind them to the desired thickness before pad printing.
John

[chris vine]

Good idea or, maybe simpler, you could cut a piece of china from an old saucer or thin tile etc.
Method would be the same as for cutting glass: Copper tube with ID of dial size, plenty of abrasive and gently grind your way through.

Chris.

[oldnorton]

Some great contributions and ideas! thank you. This thread has generated some interest.

Before I posting I did favour the idea of using one of my home printers to keep the graphics easy. I appreciate that the pad printing method is the traditional and quality way of transferring a black paint image but I perhaps will avoid having to make custom etched plates. The suggestions have led me to see that there are a range of water transfer sheets available, either specific to laser printing or inkjet. The watch man has several videos from that link above that I need to sit down and see. I have just ordered three A4 inkjet sheets for £6.

Regarding the heat experienced, perhaps we need to allow for around 150-200 degC sitting in front of the backhead and above a firedoor, so any experiments could be tested in a domestic oven. I am thinking that laser toner powder and inkjet liquid are mostly carbon filled and it is only the resins that might break down. The waterslide transfer support medium is recommended for baking to 110-130degC after application to a ceramic mug. I also feel happy that a number of white enamel paints will survive the heat as the filler is titanium dioxide - again it is the resin behaviour that is unknown.

I am going to experiment and report back here. At the moment the plan is to 1) make some small, thin brass discs; 2) paint them white, let them dry, then see if they will bake to 150, 175, 200 deg; 3) apply a waterslide transfer from the inkjet printer (Epson Durajet inks), let that dry, then bake at 130deg; 4) add an acrylic sealer (not sure if this is necessary); 5) test in the oven to see what temperature it all survives to!

Norm

[uuu]

My gut feeling is that the pressure gauge will not get as hot as 150-200C. You could try splashing water on it to see if it sizzles. I'm guessing not - but worth the experiment. Then the waterslide transfers etc. may be stable.

Wilf

[ock]

Hello Bruce,
Thanks for your video of pad printing. The ink cup is only required
on production machines with long runs say 15 minutes or longer.
For one or two impressions you can move a puddle of paint, or ink,
to and fro over the engraved cliche plate with a squeegee like the
early watchmakers did. A smaller cliche plate will serve and there is
no drive for the ink cup.
John

[oldnorton]

Nov 17, 2023 14:35:09 GMT uuu said:

My gut feeling is that the pressure gauge will not get as hot as 150-200C. You could try splashing water on it to see if it sizzles. I'm guessing not - but worth the experiment. Then the waterslide transfers etc. may be stable.

Wilf

Yes I agree with you Wilf. I was exaggerating. Pressure gauges have soft soldered parts inside, protected by the water in the U tube from 170 degC steam, but there has never been any suggestion of their failure on any small engine.

Norm

[ettingtonliam]

I'll start by saying that I've no intention of making my own pressure gauge, but having followed this thread about dial gauge faces I'm curious to know what process the commercial makers of minature pressure gauges use to print their faces? Does anyone know?

[oldnorton]

I had previously made my dummy gauge dials by inkjet printing onto white card. These did not last and after two years of loco use the dial faces were a sad, oily dark brown. I started this thread asking the question whether anyone had any information regarding small dial making. This is a report on some small success and what I found out.

I did look at the watchcomplications.com postings on YouTube. It is all about how to print watch dial faces and is professionally done, but the chap would spend ten minutes talking about something that I would like to have heard in 20 seconds. What I did learn was about pad printing. In this technique ink is picked up from an etched metal plate (or laser etched) with a rubber (or silicone) pad and then accurately impressed upon the white watch dial. The cost of the machines was in the rigidity and accurate location of the rubber pad over the dial. But the result was a professional finish.

Making the etched metal plates would have been too much for this simple one-off job of mine, never mind the transfer machine.

Mr watchcomplications then went on the describe waterslide transfer systems. He used film-free waterslide decal paper, in which the image is put on the film (yes there is a film) as a mirror image with a laser printer. Just like a waterslide transfer the image is slid onto the work but with the ink now in contact with the surface. He did use the commercial Microsol and Microfix products to improve ink adhesion. The film is now peeled off and thus a film free residue of the ink remains on the surface.

I had already bought some A4 clear sheets of ‘water-based ink-jet water transfer paper’. This is described as a film transfer. You can also buy the same thing for laser printers and in a white film version rather than clear. This was my method for making new faces for my dummy gauges:

1) Produce the artwork in CAD and output to an Epson inkjet printer with the sheet cut into A6 segments. This image shows one of the rejects as I didn’t realise how long the ink took to dry at high print quality onto a photo glossy surface, and I smudged it!



2) The paper has to be sprayed with three coats of water based acrylic lacquer, otherwise the ink will dissolve when trying to water-slide. I used an airbrush and allowed 15 minutes drying with a warm airflow between coats. Unfortunately the lacquer left a stippled surface. They were left overnight sitting on a radiator.

3) Cut out each image, soak in water for 25 seconds and slide onto the pre-painted dial face. After air drying for a few hours the transfer is oven baked to fix and make it waterproof. The temperature depends upon the substrate used but it is claimed this can be 120 degrees C for most surfaces and to a maximum of 160 degrees C.

I had previously cleaned, etch primed and white enamel painted each of my small dials. It took three coats of Craftmaster white enamel to hide the grey primer. After drying I subjected some test pieces to oven baking to test for colour stability. At 120-130 deg for 3 hours the brilliant white turned a slight off-white shade. This was a disappointment, no doubt due to the paint resins breaking down. There was no point checking for stability at higher temperatures.

I applied the transfers to the dials, let them dry in the warm for two hours and then oven baked the test samples at 130 deg for 15 minutes and they picked up a slight yellow shade. Testing at 160 deg for 20 minutes turned them a definite brown shade. More disappointment. Other samples at 120 deg only slightly yellowed, so this was used for the dials.

The dials were built into the gauge bodies with spacer rings, glass faces (sold as watch glasses on eBay) and brass shrouds.



Mounted and finished the slight yellowing does not show against the brass surrounds. At least I know they will be temperature stable to 120 deg, although time and oil plus smoke might do its worst.



I also made some diagonal stripe plates for mounting behind the water glass protectors.



What would I do to try and make a better job next time? Well, I would try acrylic, water based white paint to see if the binders are more temperature stable. I would use laser print water transfer paper to avoid the need to spray acrylic lacquer, and I would try laser paper with a white, rather than clear, film to replace the painted surface.

[mbrown]

Lovely work! Do bear in mind that the white faces of prototype gauges quickly went a definite yellow-ish hue, and often became grimy with smoke getting in. I have a couple of BR gauges in ex-loco condition which are much more yellowed than your gauges as pictured.

Nothing like being fanatically true to the original!

Best wishes

Malcolm

[JonL]

I like the Oil/no-oil gauge. I assume its just plumbed into the lubricator tee?

[chris vine]

That is a really good result for a first go!
It will be interesting to see what you get on the next iteration.

On the subject of Pad Printing, which I had never even heard of before this topic came up on the board, could you use the drill press as the operating mechanism and then get the image you want printed, either laser etched onto a bit of brass, or get one of the ME Nameplate makers to run you off the image in their usual process.

An alternative would be to ask one of the CNC boys of this manor to do a bit of cnc engraving to obtain the cliche.

I am sure you could design a simple fixture to hold first the cliche (new word meaning for me!) and then the dial blank. For a model engineer achieving the accuracy here would not be difficult I think.
Then you could use black paint which will certainly survive the temperatures, together with your previous idea of a little porcelain blank.

A fascinating topic.

All best
Chris,