How to convert one colour offset press to UV-coater?

[piotrw2009]

Good day !

This is my first post, as i found this forum an hour ago

In my small printshop we are often laminating our jobs. Laminating film is a bit expensive, so we are thinking about swithing to UV-coating, as UV-varnish is much more cheaper than laminating film.

Beacouse of costs, we want to do UV-coater by ourself - using some kind of old one-colour offset press. Beacouse UV is new thread do me, i have some questions about it:

I have the knowledge about UV-tunnel, conveyor and so on, but i have some questions about offset press:

1. Is it true, that all ink rollers in offset press should be replaced to 'UV-compatible rollers'?

2. How about spot coating - this will be a great feature, but how is it done? Is it that same kind of process that offset printing (water/ink based) or something complete else? Is it even possible to convert offset machine to make spot UV-varnish, or i need to invest in some kind of screen printer to do it?

3. If i replace ink rollers for 'UV-compatible', is it possible to make normal offset printing on this machine? I want to buy press in B2 format for this purpose, it will be nice to have possibility to print some kind of poster on it from time to time

4. What type of machine is the best for such converting? I am thinking about buying old Heidelberg SORM, KORD or Roland RZF (as i am living in Europe, so i prefer european machines).

Thanks for your reply guys !

 

[spigot]

hi mate
I will answer from what i learned in the past. Im sure it is not the best or newest however. It was an experiment at a factory who wanted to do the same thing. In the end, it was outsourced due to problems, smell, and time wasted because the press wasnt designed for it.

1- yes it is good to replace the rollers to a composite type rubber. The reason i was given is due to the washup solvents being alot more agressive to wash u/v gloss off, and can dry out, swell and crack normal rubber more quickly. There may be other reasons as well, but i didnt see any difference in the way normal and composite worked, ink milling was the same, shore was very similar etc.

2- with spot coating we used a raised type rubber plate. Cant remember what they were, the plate house made them for us. Other option is to cut away unwanted area of blanket if its a glue flap or something like that. Cutting blanket took along time and was only used for repeat jobs, so could keep old plate on, swap blanket and coat fast.

3- yes the ones i had worked fine after a very good washup.

4- i cant say what is best. I had a SORD. It was good because you could roll the blankets back and forward, and also adjust plate to blanket pressure for the rubber plates. This is important because not all presses can do this and the plates were thicker than normal, and without backing off the pressure it squeezed coating around and didnt leave a nice edge on the reversing.

Did a good job most of the time.

 

[keldrewett]

Uv varnishing

Uv varnishing

good day !

This is my first post, as i found this forum an hour ago welcome!

1. Is it true, that all ink rollers in offset press should be replaced to 'uv-compatible rollers'? You can get hybrid rubber to do both uv and conv

2. How about spot coating - this will be a great feature, but how is it done? You can print a uv duct varnish via litho.

3. If i replace ink rollers for 'uv-compatible', is it possible to make normal offset printing on this machine? See above

4. What type of machine is the best for such converting? Anything you can get

hope this helps mate!

 

[arfamoe]

Trying to print UV coating in a printing press roller train i think will be quite a challenge, i would have thought converting the dampening unit to some type of coating application unit would be better rather than trying to transfer UV coating through a litho roller train, i doubt whether you could get the volume of coating required for good Gloss. If you replace all your printing rollers with full UV compounds it is not recommended to try and run conventional ink, a better decision might be to use Chameleon roller compounds which are good for Hydrid UV inks and conventional. I still think converting the dampener would be a better way to go. my 0.02c

 

[ballykea]

Converting to UV coater

Converting to UV coater

I have been in the UV coater equipment side for over seven years and I can tell you that you are heading down a slippery slope. There are so many variables when it comes to the mechanics of a roll or spot coater that many companies that tried to do their own ended up wasting thousands of dollars. K2 Systems, although it turned out to have very bad ownership had the best idea. When they went away, several clones appeared that are quite good but expensive for start ups. IN the end, I opted to take on the distributorship of a low priced, well made UV Roller coater. We can offer a spot coater, but that business is still too small in the overall market plus the plate costs can be a challenge when looking at short runs. Our coaters start in the price range of $14,000 for new machines and can offer optional auto feed and stacker.

At the end of the day, buying our equipment or other UV Coaters from a vendor is the best and least complicated solution. All of us have already done the experimentation.

You can contact me at your convenience to discuss this in more detail.

Lou
[email protected]