Problem with Rockland kit

In this month I've tried the Rockland kit, but at the end of the works (developer and fixer), one side of emulsion disappear from the 4x5" black aluminium plate. I use a Chamonix camera and a sheet film holders different, the MPP 4x5" film holders.
According to you where am I wrong ?
One problem could be the perfect plane of the aluminium surface ?
Another, my emulsion Ag-Plus is expired from some years, but is always to a temperature of 10 °C.

I don't find Ag-Plus in Italy, another question is about the silver emulsion, can I use another brand (e.g. Tetenal or Rollei black magic) ?

Thank you in advance.
Regards

Hi. What do you mean the emulsion dissappears? It unattached from the plate or it seems "invisible" ?

Sometimes with expired emulsions you need more coated on the plate, and
if it unatrached from the plate you need to clean the he plate so the water
“sheets” off the plate ( does not stick or hang) you might need to coat your
plate and put it on something super cold to set up the emulsion so it sticks to
the plate better... or you might need to coat the plate with gelatin first as a
sub-layer to coat on instead of directly on the metal...

To tell if the emulsion is still good, you can coat a scrap of paper with it,
put a coin or something on the paper, turn the lights on and develop+fix it ( in regular print developer
not the reversal developer. ). you should see a black and white image.
if you don't, you might consider getting fresh emulsion, or trying to
figure out how much of a longer exposure you need to get an image to register on the paper. your emulsion
might have lost a lot of speed so you don't have a long enough exposure, so it seems invisible.

what color is the reversal developer you are using? is it clear? did you let it sit overnight in an open tray
to "season"? does it smell a little like amonia ? it might also be your developer is dead.

email rockland to see what advice they offer.

have fun !
john

ps. i mainly do this process with old expired rockland emulsions the double coating the plate
is what i was told by them at one point because the emulsion was old and expired. the photogram
exercise ( putting something on the plate lights on &c ) is also something they suggest in
their instructions.

You wrote "Hi. What do you mean the emulsion dissappears? It unattached from the plate or it is as if it is invisible?" My answer is "...it unattached from the plate." Before to recover the black aluminium plate I clean it with acetone for nails, and let it dry. I pour (half a 35 mm canister) Ag-Plus on aluminium and after 15-20 minutes, I put the plates in a refrigerator off, at the external temperature, but dark; at least for one day, ore more.

A person use the method below, I never tried this. In my opinion is black and white, non a Tintype. Also with the Rockland kit, I obtain only a "false" Tintype. I bought the Rockland kit because I do not want to use a portable darkroom to obtain a real Tintype.

The plate was 0.5mm aluminium sprayed with black polyurethane paint and coated with Rollei "black magic" emulsion. Exposure 4 sec @ f8. Developed in the following for 3 minutes:

5g Ammonium Thiocyanate

15 ml Rollei RBM5 hardener

30 ml Ilford Multigrade developer

270 ml water

No stop, just a water rinse. Fixed in Ilford Rapid Fixer 1+4 and 10 minute wash in cold water.

My understanding is that the Ammonium Thiocyanate acts as a silver solvent, adding contrast and giving a clearer positive when the silver image is viewed on the black background of the plate.

sorry i suggested you contact rockland colloid, i thought it was their developer + emulsoin you were using,not a
home-brew version of the developer and black magic ... i do not believe they will help you
since you are not using any of their products,,,

seeing the emulsion unattaches from the plate, it means you didn't clean the plate well enough and the gelatin in the emulsion did not bind/adhere/glue itself to the plate.
you need to clean the aluminium ( never heard of using acetone ) with washing soda/sodium carbonate/baking soda. scrub it so water runs off it and doesn't stick.
you need to either coat the plate with photograde gelatin and let it get hard. i have used food grade it works OK ...
get a pizza stone ( or something similar to retain COLD ) and put it in your FREEZER. coat your plate and put it on the stone or "cold thing"
the emulsion will stick well to the plate i do not put mine in a refrigerator, if that works do it ... you need air circulating to dry the emulsion well
i usually leave mine in the darkroom with the lights off.

contrary to what you have been told ...
silver gelatin ferrotypes are not false tintypes. they were developed in the 1880s and were popular into the 1920s+ as an alternative to people who did not
want to work with explosive collodion ( if it lights on fire it gives off toxic smoke ) and not so nice KCn. people did them not only on metal
paper as well, and "street photographers" and "carnival photographers" would make photographs on metal
and paper + post cards while people waited. i've made them
on glass as well as metal and paper...

i can't speak to your coating the plate with urethane, sometimes that works, it has never worked well for me when i started coating thing with emulsion years ago,
ALSO when the urethane gets old it yellows which some like, some don't.

i do not know the recipe you have given for your reversal developer .. it is similar to what the rockland supposedly contains
it is proprietary so no one knows for sure the amounts, but it contains dektol ( 1 quart dilute to a gallon container ) sodium carbonate, thocyanate and spent fixer ...
i do not know the chemistry particulars but from what i understand the devloper and fixer work together as a monobathdeveloper and it exhausts and then the cyanate bleaches the image
so what was black is greyish white and what was white ( clear ), well, it has the black of the tin so it appears to be a reversed image. when i make them
i use a hardened fixer, instead of putting hardener in the developer, i guess you can do both.

seeing the emulsion is sliding off the plate use something cold and maybe gelatin instead of the urethane and wash your plates really well.
the coat on paper and turn the lights on will also tell you if your black magic is dead as well.
good luck