I have used Cafelat silicone portafilter gaskets on a couple of Rocket HX machines. The portafilters locked in well with no movement.

Rocky

Not much to add but I mine works just fine. Seems to be a thinner type like an original LM 6mm but the PF locks at 6 and no leaks or shifting.

Though yes the material 'feels' less assuring I guess due to the lower friction and give compared to rubber.

Got a 'blue' one installed in my GS/3 no more old style rubber to fossilise

CSME9 wrote:Are the blue gaskets 9mm or 8.5mm, I only found 8.5mm and 8mm on the website .

Thanks, WS

E61 are 8.o Blue and 8.5mm Red. We have specific NS/VA conicals 8.3mm blue and 9.0mm red

I might try the next-thicker size on one group to see if it works better, that's a lot of rotation and seems one'll pop off sometime and break something. I had the opposite experience on an E61 machine. The naked portafilter wouldn't lock on all the way to 6 o clock, and was prone to rotating off (including entirely off a couple times, which is exciting) until I used that gasket. The rubber gasket was a little old/hardened but also, that portafilter is a hair thicker and locked in better with the squishier silicone gasket.

I have posted this tip before and will again, Unfortunately cafelat does not make a group gasket for my machine,So I use a silicone o ring for a gasket in my group, I had some portifilter creep also,I did notice that I had no problem with my bottomless ,Looking at the ears on the bottomless I noticed it had slight machine marks on them. So I etched lines into the chrome on the ears (top and bottom) of the other portifilters to create more friction which fixed the problem. I hope this may help someone with this issue. Jim