Printing white transfers (decals).

[John Candy]

Two items on my "to try out/do" list for a long while have been 3D printing and producing white decals (and multicoloured ones for dark surfaces).

The obstacle to 3D printing (for me) has been (and remains) that I have never got into CAD.

I have however, for many years, been producing waterslide decals on laser printers but the constraint on what can be reproduced has been the inability to print in "white". Ordinary laser (and inkjet) printers can successfully print strong colours to overlay on pale backgrounds BUT colours become transparent on darker backgrounds. The only "workaround" has been to print on white (as opposed to transparent) decal film but this will not work for intricate shapes or lettering, where the cutting needs to be "bang on" the boundary of the printed image.

There is a new generation of laser printers able to print in white (they are adaptions of standard laser printers) which are lower in cost than the sublimation printers (very expensive) which have previously been available (e.g. the "Alps").

So, whiling away my time indoors, I "invested" (if that is the right term!) in a SunAngel 33TW A4 printer to attempt to produce white and multicolour decals. The printer is an adaption of an OKI C332 with special software and drivers and works by printing a white background to the coloured image, so the effect is the same as if the colours had been printed onto white paper, whatever the background colour of the model. So white lettering, shaded ("blocked") lettering and coloured designs should all be possible.

White lettering is straightforward ...... print as normal onto waterslide film (just need film with blue backing paper so you can see what you have printed when the time comes to cut out individual items). Multicolour is a bit more tricky .... just how much more I will not know until I have tried it! The image has to be inverted, because, although the printing is all done in a single "pass", the CMY colours are printed and then overlaid with the white ..... the white is on top. To get the image the correct way up, a "rub down" (as opposed to waterslide) technique is employed. The image is overlaid with a sheet of "tacky" film (putting the white overlay side of the print onto the tacky sheet) which serves to reverse the image ready to be cut out and applied to the model.

I have the printer set up and am currently awaiting the arrival of the blue-backed waterslide film and the rub-down media to "give it a go" ..... I have plenty of clear waterslide film and will do a test print tomorrow but, with white backing paper, it will difficult to see the white print when cutting out!

More news later in the week , once the special papers have arrived.

John.

[John Branch]

John, very interesting, please keep experimenting.  This has long been one of my headaches when trying to get a way of replicating coats of arms etc on railway subjects.  A commercial product rarely exists and when it does it is horrendously expensive.  My solution to date has been to print on white decal paper and include a border (and exposed areas within the transfer ) printed with ink as close as I can get to the background body colour.  This reduces the accuracy with which I have to cut the subject out, but does involve a large amount of trial and error to get the border colour as close as possible to the actual body colour.  Your solution would potentially be a lot neater.
John

[John Candy]

John,
In the past I have used white film to successfully produce white lettering on black and I also have produced "Blue Circle Cement" roundels successfully.... but anything with an intricate shape or requiring background colour-matching (other than black) I have avoided.
If this new process lives up to the promises, it should be able to produce fulla colour coat-of-arms to apply over dark surfaces.
Watch this space!
John

[John Candy]

After several years of anonymity, Worthington No.1 has its number at last!








I also quickly printed a few crests as a rough and ready test and applied them to clear acetate sheet. The photos were difficult to take because of poor lighting and reflections but show the clear sheet held over a black backing.









John

[Gavin_B]

They are looking great! 

[cabbage]

Jealousy...

Regards

Ralph

[John Candy]

A day well spent!

Started at 6am and designed, printed and applied transfers to a wagon which has stood "naked" for about nine years.

J.& N. Nadin & Co. Ltd. owned Stanton Colliery (Burton-on-Trent) and operated many depots in London, Worcester, Coventry, Leamington Spa and several other midland towns.
The wagon was built from a Peter Wood kit and detailed from a photo in one of Keith Turton's P.O. Wagon books.










John.

[John Candy]

The British Quarrying Company Limited was formed by the amalgamation of 6 quarrying companies around 1930.
The wagon modelled here was owned by J Arnold & Co. prior to amalgamation and was registered by the GWR in 1924. It is a 5-plank 1923 roadstone wagon (they had metal plated floors for protection) and a kit for this type is available in the "Flexikit" range.   
Another wagon (of an earlier type) appears in a post-war photo with the BQC lettering for Ceiriog Quarries, branded "Granophast",  (tarred granite roadstone) and marked "Empty to Criggion S&M Rly"(Shropshire and Montgomeryshire Railway part of Colonel Stephens light railway empire).
My next effort will be the New Northern Quarries Co. Ltd."Quarrite" roadstone wagon .... another part-finished wagon which has been gathering dust for far too long!

John.

[MikeWilliams]

Very good indeed John.  How did you get on with transfers over that deep detail in G3?  Particularly the A and D of NADIN which goes over strapping and catches?  I use Decalsol and Decalset but never manage to do it to my satisfaction.

Mike

[John Candy]

It all went on much more easily than I expected....and without any wastage... I had expected at least a 25% failure rate so printed spares which were not required. Once the lettering was in position, I just squeezed hard with a paper towel until the transfer did what I wanted. I then applied two coats of decasol and left to dry. Followed that with two coats of Johnson's "Klear". 
The film I use appears much stronger and more flexible than commercially printed transfers I have used. It is possible to squeeze, stretch and generally abuse it without it tearing/breaking. If I tried to do the same with the GRS transfers they seem quite brittle by comparison and would disintegrate!

John.

[MikeWilliams]

Thanks John, that's very encouraging.  I know waterslide transfer film can vary, but if printed commercially maybe they have been in stock for a few years, whereas your own are very new.

Look forward to seeing some more.  But you really should et back to locos (hint hint).   

Mike

[John Candy]

..............and herein lies a tale.

Many (many) Moons ago, I made two pre-production castings from the "Flexikit" moulds for the RCH 1923 stone wagon. The intention had been to commission a transfer producer to supply sets of "Quarrite" transfers to accompany the kit. Why "Quarrite"? Well, the Flexikit tar tank wagon, which was in preparation at the same time, was based on a photo of a wagon owned by the same company which owned the "Quarrite" brand of tarred stone.

One set of castings I painted in the red/black colours of the New Northern Quarries Co Limited (i.e "Quarrite") and the second set I painted in red and assembled the latter set as a completed wagon (now the "B.Q.C." example).

The reason for not completing the erstwhile "Quarrite" example? Well, the proposed transfers would have been of the "rub down" variety and the supplier told us (Mike and myself) that it was advisable to apply to unassembled sides, since extreme pressure would be required to make the transfers stick over the strapping, etc.

Having considered the risk of failure balanced against the (not inconsiderable) cost of the transfers, it was decided to shelve the idea. Instead, I prepared waterslide sets of "Joseph Cole" transfers in black, to be applied to a yellow/black body. Whereas it is possible, with a normal printer, to produce dark transfers to apply over light backgrounds, it is not possible to produce light colours to apply over dark backgrounds...and definitely not white.

So there matters remained until the arrival of the SunAngel (white enabled) printer.

Several years later than envisaged, the "Quarrite" wagon sides have now been decorated!
It just remains for the rest of the wagon to be completed!

John.

P.S. I wonder whether there would be a demand for Flexikit wagons with pre-painted sides (rather in the manner of the Slaters kits in Gauge 0)?

[MikeWilliams]

Very impressive John.  A breakthrough.

Mike

[John Branch]

John,
This thread was busy last April as you described progress with producing transfers (decals) that contained white lettering which could be used on dark-coloured backgrounds.  From the photos of PO wagons posted at the time, this was a most effective technique.
As I think  I mentioned  at the time, my problems in this area centre around being able to reproduce a background colour on my printer, so that I could use white-backed transfer paper, and cut the image out so that the transfer "merged" into the background.  This has always been fairly approximate, and sometimes works and more often does not.  I neither have nor anticipate the additional complications of applying the transfer over strapping, etc., nor of wanting white lettering on the transfer itself.  The majority of my subjects are yellow (gold) letters on a scarlet background.  Do you believe that your technique would deal with this?

Best,
John

[John Candy]

John,

It can produce yellow on either a coloured or clear background to place over any background colour.
Examples are the pictures further up this page (Worthington No.1) and (apart from the wagon examples) I printed the transfers for the three LB&SC Terriers built by' 753' Mike Palmer (the names, Boxhill, Ewell and Stepney plus the lining).

Regards,
John.