Screen bolt

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AndyPanda

Screen bolt

Post by AndyPanda »

So ... I know this is addressed in old threads (I've been digging thru the archives) and perhaps I should be posting in those many years old threads instead of posting a new one. But .... Hey, I'm a fresh newbie S1 owner and excited ... so I'm posting.

I thinned the head of the screen bolt. I tried the alternate screen arrangement and didn't like it ... so I've got the screens in the stock arrangement but with the thinner bolt head. I just pulled two shots with 16grams very lightly tamped in the double basket. Both shots poured beautifully with barely a hint of bolt head impression in the top of the spent puck.
ScreenBoltPuck.jpg
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ScreenBolt.jpg
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sorinherea
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Re: Screen bolt

Post by sorinherea »

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AndyPanda

Re: Screen bolt

Post by AndyPanda »

Thanks for the pictures. I just got back from the hardware store with my stainless Phillips head screw and a few minutes with my dremel cutoff wheel with the screw in a drill chuck and voila! I can get 18grams in the double basket now without any screwhead dent. Anyone using the precision triple basket? Is it worth ordering?
ThreeBolts.jpg
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AndyPanda

Re: Screen bolt

Post by AndyPanda »

I know there are different grades of Stainless Steel ... I just bought my stainless bolt at the local hardware store. After only two days use, the bolt is black - compared to the original bolt that has been in use for many years. Question for those of you that replaced your screen bolt: Did yours blacken like this one? Or did you order some specific grade of Stainless?
ScreenBolt_Blackened.jpg
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AndyPanda

Re: Screen bolt

Post by AndyPanda »

After seeing how the hardware store stainless bolt turned colors so quickly, I worry about corrosion. So I switched back to the original bolt but thinned the head a little more:
ScreenBoltThinned.jpg
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ScreenBoltThinner.jpg
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MDL
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Re: Screen bolt

Post by MDL »

Do you really believe that the volume difference between the "stock" and your thinned bolt has any significant impact on the quality of your shots? It must represent a tiny fraction of the volume of the basket?
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Lav
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Re: Screen bolt

Post by Lav »

It will increase the risk of channeling if you have a "sharp" dent.... I changed my bolt to a domed type, but this looks even better


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AndyPanda

Re: Screen bolt

Post by AndyPanda »

I'm of the school that you should not tap the portafilter after you tamp - I don't want to risk fracturing the compressed coffee puck. I also do not twist the tamper. I cringe when I see others tapping and twisting after they've gone to such great lengths to have fresh coffee, ground perfectly, distributed carefully, tamped precisely and then they smack the portafilter with the tamper and twist the tamper - seems like it can fracture the structure inside the compressed coffee. Point being that I try to leave the compressed coffee as undisturbed as possible.

So my intent was to be able to use enough coffee in the basket that it would reach or nearly reach the screen without having the bolt head dig in and fracture the puck.

With that said --- in the past few days I've been experimenting with lower volumes of coffee and I've been getting better shots with 13-14g, grinding finer, lighter tamp and leaving lots of headroom. The spent puck looks soupy on top without coming close to the screen at all. Surprise to me.

But at least with the thinner bolt head I have now, I have the option to pack in more coffee so the puck presses against the screen when it expands and without getting disturbed by the bolt head.
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chas
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Re: Screen bolt

Post by chas »

I use a triple basket so that I have more headroom rather than to pack in even more coffee. I think you definitely want to prevent or at least reduce contact with the brew head which will create a disturbance in the force!
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goodboyr
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Re: Screen bolt

Post by goodboyr »

+1000

Triple basket is the way to go. With 16.5 gm coffee load, there's plenty of headroom.

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La Spaziale Dream and Baratza Sette 270W
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