Looking for help firing old decals

[Rachel Hawkins]

Hello! I recently got a bunch of older decals from someone who was clearing out their collection. He said fire to Cone 018 - 016. I scoured the internet trying to figure out more info on speed, temps, etc., and decided to go with a Slow Cone 018 and figured I could go hotter (or faster?) if needed. (I bisque fired to Cone 06 or so and glazed to a hot Cone 5 with a 30 minute hold prior to this firing.)

They came out okay, but a couple weird things:

-the texture is more rough/brittle to touch than I expected. I had imagined it would just sort of melt into the glaze, but there's a definite rough feel to some of the pieces where the decal was placed that isn't awful, but isn't ideal. Is that normal? I've never used decals before but it doesn't seem right based on what I've seen/touched in shops etc.

-in some areas you can see the outline of the decal paper itself? like, if you look closely, you can see the shape I cut out (mostly on the dark green coaster). Is this due to the glaze color underneath, or could it be underfired?

Anyhoo I guess my question for anyone who has decal experience/has used vintage decals is- do we think a hotter firing and/or faster firing could resolve any of these issues? I'm worried about things burning off and had read somewhere that decal firings should be slow which is why I went with the original settings I chose. Or is it possible the decals feel brittle or show the cut out shape because they're just old? And maybe I should just resign myself to putting them on things where people won't really care if the texture is off? I was already planning on keeping them off of anything food would touch so wouldn't really be hard to do this. 

Thanks so much!

[Mark C.]

Im vintage and have fired decals 45 years ago-the meduim has to stick to the pot(water based meduims-get wet and let dry)-not curled up and they fire slow to the large cone temp range stated -so 018-016. I used to watch the cone drop (large cone) Before computer kilns . I suggest  using large cones and  maybe the hotter end cone wise if you see paper outlines. That also could be colorants drifting ?A nice decal pot has NO outlines and no rough textures

I do not think age if stored right will affect them.I have some 45-50 year old ones but have not ues them-butterflies and some ships 

Some of the colors may change if they get to hot as well.

Most decals are not food safe anyway.

I fired all on them on horizontal vases mostly in the mid 70s

they all work best on shiny smooth glazes-not matts or semi matts

[Rachel Hawkins]

Thank you Mark! I had not known that about matte vs. glossy glazes, that might explain some of the issue.

I will try my next batch with a slightly hotter firing and see if that makes a difference. 

I also applied some new ones yesterday and wondered if any of it could be because there's a correct front/back to the decals and I've maybe applied in wrong direction? Not sure how obvious that would be or if it would matter but on one there was a small signature of the artist on one and I realized I'd applied it backwards.

After figuring that out I've been assuming the correct direction to apply the decals is the pot becomes the paper backing (i.e. the paper would have been in between pot and decal if left on?) 

[Mark C.]

yes front and back will matter. The front needs to be up. Think of decals as china paints on a surface (the decal meduim) the medium holds them and burns aways and the chine paint fuzes to surface of a shiny glaze

i.e. the paper would have been in between pot and decal if left on? yes this is true

 

Edited August 9 by Mark C.

[Min]

I know a lot of the china paints and decals from that time contained lead, I wouldn't be using them on food bearing surfaces. Apart from the lead aspect they are not durable for food surfaces either.

[Rachel Hawkins]

Yeah I'd planned to use these little lead test swabs I have on them to make sure. If that came back positive I'd switch to outsides of vases or planters with them.

For now I'm mostly doing coasters and/or the outside of a mug where a mouth/food wouldn't come into contact. I don't think these are that old and some of the brands appeared to be made for dinnerware so I was hopeful I was good on the lead/food safety front.

[Callie Beller Diesel]

Make sure any lead test swabs you use are ceramic specific. The ones meant for paint can give false results on china.

I have seen some people have problems with certain decal paper brands, or some older decals leaving transfer paper outlines left behind. They don’t have to be a deal breaker. The best way to make this look inconspicuous is to cut them out neatly, and as close to the design as you’re willing to get. It does sound to me like the ones you have need to be fired closer to the 016 mark. If you soaked your decals in water and slid the paper out from between the decal and the pot to apply them, you did it right. If you flipped them face down, they’re upside down, and the paper burning out would have affected their adhesion. The only other troubleshooting thing might be if you didn’t let them dry for at least a few hours before firing them, or if they weren’t well squeegied down. If there was any water or air still trapped under the decal, that’ll mess with your day. 

No decal that is fired on top of the glaze at that low temperature is fused fully with the glaze, whether they’re china paint or lustre or etc. They’re cured well, but will wear off with improper use or enough abrasion. If you look at most older china patterns, the surface that contacts the food is often left white, and decoration is on edges or outsides. And you’re not supposed to put it in the dishwasher. Also, it’s not just lead that was used to make some of those colourants. There may be cadmium reds or yellows. And a dish sold as a coaster can easily be repurposed into a dip dish, or prep dish, or holder for dental items. Just something to bear in mind.