Monolith grinder mod - ensures portafilter doesn't fall out

#1: Post by **justneel** » March 27th, 2020, 2:57 pm

I don't know if others have had this problem. After placing the beans in the grinder and turning it on, I'll step away from the grinder to get some milk. During that time, once in a blue moon, the portafilter will vibrate enough for it to rotate in place. Even more rare, but has happened to me one time, the portafilter will rotate enough that it falls out of the grinder and spills the grounds all over.

Well to put my mind at ease, I wanted to create a little lip to ensure the portafilter doesn't fall out. I have a 3d printer at home, and plenty of time on my hands now being stuck at home.

So here it is. Printed in PETG.

If you're interested, I designed it in OnShape and you can print it yourself. The cad has a boolean to flip it for left and right side of the machine.

https://cad.onshape.com/documents/7db16 ... de%3Dfalse

#2: Post by **wachuko** » March 27th, 2020, 3:21 pm

Thank you!!! Let me download.

Printing tonight!!

#3: Post by **wachuko** » March 27th, 2020, 3:41 pm

Sorry... is there an .stl file for download?

I do not have an account with OnShape... not sure how to take it from that link you provided to get it into a format that I can print.

March 27th, 2020, 3:56 pm

You probably will need to create an onshape account, it's free though. Then you right click the item and hit export to get an STL.

I tried uploading it to thingiverse, but they've been having server issues lately, and my uploads just fail.

March 27th, 2020, 4:04 pm

Let me try that... when I went there it had option to buy or for Education... and Education asked for school information and such... not sure where the Free sign up option was.

Disregard my PM then. Thank you.

I have issues as well since not all portafilters are the same size... some fit just right and others are loose... this would solve all of that!

EDIT: Found the Free trial link: https://www.onshape.com/products/free

#6: Post by **3cordcreations** » March 27th, 2020, 6:34 pm

Very neat idea and a nice fit! When I had a v2 conical the pf would vibrate too much for my liking so I took off the forks and would just hold the pf in place. Most people don't have 3D printers so you may be able to sell these if you want to print them and list a few on here. As long as it doesn't become as business I think you comply with the admins.

Good job

#7: Post by **Peppersass** » March 28th, 2020, 12:49 pm

I dealt with the problem by inserting strips of 3M double-sided foam tape into the fork slots. The tape is covered on one side with a peel-off plastic strip so it won't stick to itself in the roll. I applied the sticky side to the forks and left the plastic strip on. I adjusted the fork separation so the tape compresses slightly when the PF is inserted. The slight friction and pressure from the tape on the PF ears keep it from moving. I expected to have to adjust the forks closer together periodically as the tape permanently compresses, but that hasn't happened (yet).

I got the tape years ago from Radio Shack. I believe this is the same stuff.

#8: Post by **DaveB** » March 28th, 2020, 1:26 pm

It's pretty simple to adjust the forks to get a slight amount of drag, so that it's still easy to insert / remove the portafilter and yet there's no way for it move - let alone fall out. I just readjusted mine after using another espresso machine for several weeks; might take a few tries to get it perfect, but perfect it is (each and every time I adjust). While I admire the engineering, it seems like a solution in search of a problem.

Am I missing something?

#9: Post by **wachuko** » March 28th, 2020, 1:35 pm

I just want to thank you Neel for solving this problem in such an elegant way. The design is outstanding. Perfect fit and now, no matter how much it vibrates, the portafilter is not falling off!!

If the portafilters are identical, then there are no issues since you can adjust the forks so that they slightly drag on the portafilter... The issue that I have is that the naked portafilter is somewhat narrower than the double-spout... So I had to adjust for one or the other... Now I can adjust the forks to the double-spout portafilter width and, with this mod, the naked will not shake itself out!! Just brilliant!!

#10: Post by **DaveB** » March 28th, 2020, 1:50 pm

^^ How about some footage of inserting / removing portafilter?

wachuko wrote:The Issue that I had was that the naked portafilter is somewhat narrower than the double spout one...

I just checked, and my spouted is a tad narrower than my naked - and fits loose. Doh!

I guess I'll watch it closely on the exceedingly rare occasions I use the spouted one. Might be worthwhile to try Dick's foam tape trick to see if it works for both.