I finally got my printer yielding reasonable results. But, the fully printed tool is not as smooth as the one that Luvmy40 made for me. Mine was a little hard to turn with the tiny knob, so I made a finger catch handle that seems to help. It's very easy to design one, but I'll put the file here if you want to try it.

Printed and the tool seems to work well in fluffing the grounds and distribution, atleast visually.

However I'm getting a lot of channeling - the needles seen to be the right size and "almost" touching the bottom (5 longer needles) and about 1-2mm below the top of the bed (remaining 5 needles)..

Any suggestions on how to debug this problem? I don't get channeling when I manually wdt using a 9-pin wdt tool at the same grind setting.

I love this conceptually and love reading about people making their own mods and having success.

I'm continuing to follow this in hopes that someone will make it more low-profile (shorter) and to see how it evolves.

Is it possible to 3D print (or finish a 3D printed product) in a way, or material, that makes it look a bit more finished? IE, doesn't have all the tell-tale 3D-printed surface irregularities and patterns? Or maybe it is but just cost-prohibitive due to the printer or raw material needed?

selfiegram wrote:However I'm getting a lot of channeling - the needles seen to be the right size and "almost" touching the bottom (5 longer needles) and about 1-2mm below the top of the bed (remaining 5 needles)..

Any suggestions on how to debug this problem? I don't get channeling when I manually wdt using a 9-pin wdt tool at the same grind setting.

Can you post a few images of channeling? Different WDT can affect the extraction which may require changing of grinder setting.

selfiegram wrote:Printed and the tool seems to work well in fluffing the grounds and distribution, atleast visually.

However I'm getting a lot of channeling - the needles seen to be the right size and "almost" touching the bottom (5 longer needles) and about 1-2mm below the top of the bed (remaining 5 needles)..

Any suggestions on how to debug this problem? I don't get channeling when I manually wdt using a 9-pin wdt tool at the same grind setting.

I spin mine 20 times and get excellent results from my BDB.

TN, one could print these on resin printer for a more polished look. It would be quite a bit more $ for resin over filament and it would likely take several tries to get the slicer set up perfectly for the gears to work smoothly and not end up with a lot of liquid filled voids. I'm sure it's doable, but is the juice worth the squeeze?

Capuchin Monk wrote:Can you post a few images of channeling? Different WDT can affect the extraction which may require changing of grinder setting.

Yes, I'll post a video tomorrow morning. I've been doing 8-10 rounds of Umikot. Visually things look fluff and well distributed at the top; but when I use jkimmakes' wdt tool (attached photo next to Umikot), I don't see any currently.

luvmy40 wrote: I spin mine 20 times and get excellent results from my BDB.

TN, one could print these on resin printer for a more polished look. It would be quite a bit more $ for resin over filament and it would likely take several tries to get the slicer set up perfectly for the gears to work smoothly and not end up with a lot of liquid filled voids. I'm sure it's doable, but is the juice worth the squeeze?

I am curious, for the standard double shot breville BDB basket, what size base did you print? I am using the 24mm base with the 55mm and 65mm cut pins.

I'll check when I get home today. I've printed several different sizes for other people and I don't remember which one I did for the BDB.

Which grinder are you using?

Is your coffee fresh?

Etc., etc., etc.

DF83 is the grinder. Yes, coffee was roasted 2 weeks ago at home by me, and sitting in a Ziploc with one way valve. I opened the bag about 4 days ago and transferred the beans to an air sealed jar. Kenyan city+ roast.

Video of channeling included at the bottom. Pictures of the puck prep as well.. Unfortunately I realized too late that the video was not focussing on the mirror, so its not very easy to see. I will update the video when I brew the next one.

This was the ground after I transferred it from dosing cup to PF:


This is after 10 rounds of Umikot:


After vertical tap:


After tamping:


Before placing in group head:


Finally the video of bottomless pf. It didn't channel a lot today for some reason, but you can still see some minor channeling. Apologies for the lack of focus on the mirror - I only realized after I took the video. FYI, this is dialled in by taste; so "grind finer" applies, but I prefer the taste of the faster shot. Plus, grinding finer is likely to make the channeling worse anyway. I also skipped the first 15 seconds of pre-infusion when recording the video.