Tetenal Colourtec RA4 processing

I have just bought a Tetenal RA4 processing kit for use in roller transposr machines (38 degrees).

If I am reading the instructions rightly it seems that the working solution will last 8 weeks?

Can anyone confirm I am reading this correctly?

Thanks
Matt

Matt5791 said:

I have just bought a Tetenal RA4 processing kit for use in roller transposr machines (38 degrees).

If I am reading the instructions rightly it seems that the working solution will last 8 weeks?

Can anyone confirm I am reading this correctly?

Thanks
Matt

Click to expand...

Yes, it can stay for 8 weeks if you take some precautions:
* always empty the RT at the end of the session
* store solutions in full bottles
* rinse the RT thoroughly at the end and at the beginning of the session

Personally, I keep my Printo filled with water between sessions. This helps to avoid buildup of dirt, tar, etc... I've noticed increased storage life since I started doing this. I guess that if you don't do this, some chemicals remain in the machine, get oxidized and ruin the developer that you poor in afterwards.

Note also that I'm talking about amateur usage. I haven't done any denitometer readings, but I do recognize bad developer/blix from experience (bluish blacks, yellow whites, ...)

YMMV, ut this is pretty solid stuff.

Thanks for that - that is a pretty handy shelf life because othwise it would get rather expensive for the fairly small amounts I'm likely to do!

I also have a printo so thanks for the tips on that.

It is the developer which can cause black deposits? when I bought the printo the previous owner had been a bit lax on washing it out and the one module had loads of black deposit.

The reason I ask is that I also use my printo for Black and white - I have 4 modules so I guess I should reserve two modules for colour only? or can I get away with just reserving one module for RA4 developer?

Thanks,
Matt

I also run a printo and use it for RA4 and B&W. I only have two units plus the intro unit.

I drop the RA4 bath as soon as a session is finished as my printing schedules are sporadic. That said the keeping qualities of RA4 are quite unbelievable, compared especially to previous colour processes.

I think you will find that RA4 chemicals keep longer than specified, just watch for blue blacks as the bath is nearing either a time or paper maximum. Blue blacks are a good indicator of your developer being exhausted.

I check and usually wash any tar buildup on the developer bath rollers at the end of each session. This takes a maximum of about 2-3 minutes and saves me a lot of grief down the track.

Switching to B&W or back to RA4 is easy, the unit is clean from the previous session and I just add solution. I've been doing this for about 7 years now and I haven't had any processing problems.

I have sometimes left RA4 in overnight and come back in the morning with no problems, except I found the first set of rollers on the dev tank always got tar buildup where they had been exposed to air overnight.

Mick.

Thanks for that Mick - really helpful.

I just enquired about new exit rollers for the printo (one module has a rather worn out set) £70 each - and I cant see much poing replacing one, so that is £140 a pair.

What is nice is that it seems everything is available, normally from stock, for the Printo.

Matt

Matt, don't know how long you have had the Printo, but I've had mine from brand new.

One of the instructions supplied is to ensure that the exit rollers are kept apart when the unit is not in use.

Originally the units were shipped with a little plastic thing shaped like a big capital letter "C". This plastic thing is slipped on either end between the exit rollers and keeps them apart.

The exit rollers are a soft material as they are designed to squeegee the paper as it exits the bath. Keeping them together without movement, allows them to stick together and pull bits of roller material off, destroying the roller bit by bit.

Mick.

I bought the printo recently second hand - someone had not kept the rollers apart and one module they are in quite bad shape. I do have some of the "C" shaped plastic things so I will make sure these are used.

I slip a sheet of plastic between the rollers often too - I find that this seems satisfactory most of the time - I use some damp proof membrane normally used ofr building and placed just above ground level in walls. It is a good thick gauge.