jamesshaw

CAn anyone please help me????

Im trying to strip a stencil off one of my screens and there is still a lot of diazo emulsion on there. I havent ever had any problems like this before and have done dozens of screens. I have however got my emulsion from a different supplier and when it dries it dries blue.

A lot of it has come out... mainly underneath where I had my packing tape, but the bit that wasnt covered by the tape seems to have stayed.

Any help would be greatly appreciated.

Thanks

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darwinchristian

A couple things...

Quote: Originally Posted by jamesshaw I have however got my emulsion from a different supplier and when it dries it dries blue.

is the stencil remover you are using formulated for the diazo-type emulsion you are using?

did you leave the remover on the screen too long before you took the washer to it?

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jamesshaw

The stencil strip is compatible yes. I could have left it on there too long though yes.

Ill try re doing it. Ive even scrubbed it till my arm is tired.

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classicsjunky

I had this problem before. I went to the local spray car wash and blasted it right off.

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darwinchristian

Quote: Originally Posted by jamesshaw I could have left it on there too long though yes. Ill try re doing it. Ive even scrubbed it till my arm is tired.

yeah it sucks but if you leave it on too long it can link that emulsion permanently and even ruin a screen.

Quote: Originally Posted by classicsjunky I had this problem before. I went to the local spray car wash and blasted it right off.

i use a 1500 psi pressure washer and it does the trick nicely. i don't know how strong the car wash ones are but i'd be careful to blow out the screen. especially if it's older.

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ddspecialties

We use ER-35 recaimer and a 1500 psi pressure washer. It is fast and simple. wash out the ink first them hit it with ER-35 and pressure wash.....screens are like new again.

 

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davisint

Quote: Originally Posted by jamesshaw CAn anyone please help me???? Im trying to strip a stencil off one of my screens and there is still a lot of diazo emulsion on there. I havent ever had any problems like this before and have done dozens of screens. I have however got my emulsion from a different supplier and when it dries it dries blue. A lot of it has come out... mainly underneath where I had my packing tape, but the bit that wasnt covered by the tape seems to have stayed. Any help would be greatly appreciated. Thanks

I am guessing that your screens were underexposed. If the emulsion is not fully exposed, the emulsion that is not cross linked can be locked into the mesh by solvents. This might explain why it seems that the emulsion under the tape reclaimed but the rest did not

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RichardGreaves

Quote: Originally Posted by jamesshaw I have however got my emulsion from a different supplier and when it dries it dries blue. A lot of it has come out... mainly underneath where I had my packing tape, but the bit that wasnt covered by the tape seems to have stayed.

The only only process clue you offer is that you were able to reclaim the stencil protected by tape.

I assume you taped the stencil after you exposed it. This means that something you put on the stencil - ink or wash up probably made the stencil resist reclaim chemical.

You don't mention what the old emulsion was - or what the new emulsion is, except to write it is blue. Do you mean after it is exposed? Adding diazo (yellow) to blue emulsion should make the stencil green. When you expose the stencil with UV energy, it returns to a blue color - so that's a good sign that you have properly exposed the stencil.

Diazo stencils are not really as sensitive to under exposure lock in as SBQ stencils, but if you under exposed your new emulsion because you used the same exposure as your old product, chemicals may have locked the stencil in the mesh.

You may have purchased a water resistant stencil that is much more difficult to resist.

You don't write what you are using as a stencil remover or if you are using a pressure washer.

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