# IMS integrated shower screen GA200



## Robin Red (Apr 24, 2018)

Any advice appreciated,

I have upgraded my Gaggia classic with a brass group head and IMS shower screen GA200IM. My dilemma is that, do i tighten the center screw fully as the chap at The Espresso shop said i should, but this eliminates any flex in the screen and it fits flush with the grouphead this results in no "rain shower effect" which i think i am try to achieve. or do i loosen screw and then the water pours through the four outlets on the group head resulting in water coming out the sides of shower screen. Each method results in water not coming through all the holes on the IMS shower screen which i thought it would.

Now maybe the invisible magic "rain shower effect" happens when the portafilter is engaged as it may hold the water on the surface of the coffee longer than just watching it with no portafilter??

TBH if i cant find a solution then i'll be a trifle annoyed as wanted to improve my shots. i was surprised to see that the brass group head water outlet holes are smaller than the factory fitted grouphead which shoots rather than flow to water out.

Anyways hope i get some tips

thanks in advance


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## El carajillo (Mar 16, 2013)

Under free flow Ie without the charged P/F in place it probably will not come out as rain shower. Tighten screw firmly (that is NOT screwed in very tight).

As there is not a "seal" between the screen and distribution disc you may have a slight dribble of water around the edge of the screen but this is inside the coffee basket when the P/F is tight up against the group seal.

When you have coffee in the basket and tamped, this holds the water back allowing pressure to build up and the water will come through all the screen holes. Yes sometimes you do get deeper holes where the outlets are in the distribution disc.


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## AndyZap (Dec 29, 2016)

I use a small screwdriver which I hold with my fingers by the shaft when tightening the screw. This gives about the right amount of tension. I do see "shower" after the screen and the brass holder cleaning (just after descaling whole machine with Puly Baby or both removed and had a shot of Cillit Bang followed by washing-up liquid. I prefer to clean them this way instead of back-flush). After a few shots it does not "shower" that nice, but I do not think it matters much when inside the PF - as said above.


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## jj-x-ray (Dec 31, 2017)

I have the same issue. Makes it problematic purging or filling a cup to warm It up as the water goes everywhere if to loose


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## ashcroc (Oct 28, 2016)

I have mine tightened until it just starts to deform. One thing to try for if possible is not having the exit holes from the dispersion block directly over holes on the screen.


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## dev (Jul 28, 2017)

Having gone through most uogrades, i never found the shower screen a priority.

Replacing the aluminum plate however is a must since it allows for proper backflushing with a detergent like pully caff.


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## Robin Red (Apr 24, 2018)

Thanks very helpful


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## Robin Red (Apr 24, 2018)

Hadn't thought of that thanks


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## les24preludes (Dec 30, 2017)

dev said:


> Replacing the aluminum plate however is a must since it allows for proper backflushing with a detergent like pully caff.


Is this because it corrodes aluminium? What if you use citric acid?

Another question - if your existing shower screen is flattened by previous over-tightening, is there a trick to re-form it?


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## ajohn (Sep 23, 2017)

les24preludes said:


> Is this because it corrodes aluminium? What if you use citric acid?
> 
> Another question - if your existing shower screen is flattened by previous over-tightening, is there a trick to re-form it?


I don't have a gaggia but other machines use the same sort of set up. Nip it up - that's tighten until you feel things firm up when the screen has flattened and no more. When you remove it you will find it springs back to it's original shape. If it doesn't the brass / aluminium plate is at fault - rather unlikely.

John

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## El carajillo (Mar 16, 2013)

les24preludes said:


> Is this because it corrodes aluminium? What if you use citric acid?
> 
> Another question - if your existing shower screen is flattened by previous over-tightening, is there a trick to re-form it?


The aluminium dispersion block corrodes from the acidic action of the coffee as well as de-scaler. It is highly recommended that you change it for a brass one.

The normal shower screen is only slightly "dished" and the countersink area forms a spacer. Unless the countersink has been completely crushed it should seat correctly. How are you judging that it is completely flattened ?


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## les24preludes (Dec 30, 2017)

El carajillo said:


> The aluminium dispersion block corrodes from the acidic action of the coffee as well as de-scaler. It is highly recommended that you change it for a brass one.
> 
> The normal shower screen is only slightly "dished" and the countersink area forms a spacer. Unless the countersink has been completely crushed it should seat correctly. How are you judging that it is completely flattened ?


Not completely flattened, but if you screw it really tight it isn't quite so dished. Not much in it, though.


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## El carajillo (Mar 16, 2013)

That should not cause a problem, as long as the water can spread out behind the screen.


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