Turin DF64V Grinder - Page 9

#81: Post by **malling** » May 31st, 2023, 11:56 am

It's a bit surprising that they still have some notable issues in V1, you would think with their experience that only minor issues would present itself at this point.

It's going to be interesting how the 220-240v version behaves as it's now been announced for the European market and will be ready in 7 weeks time. But €590 is definitely a reasonable price.

#82: Post by **Kran** » June 4th, 2023, 6:29 pm

With the stock burrs the lowest I could cold (dump all beans in then hit go) and hot start (start grinder, dump whole dose in) were 900rpm and 700rpm, respectively. This is with a full dose at espresso grind dialed in for 1:1.5 in 30s.

I just swapped in SSP cast burrs and can cold start through the entire rpm range, down to 600 rpm, at espresso grind.

#83: Post by **epoon2** » June 9th, 2023, 6:56 am

Hi all,

From what I know from gear boxes or basic physics, when I achieve lower RPM, my torque should be higher right? It's like a car, I switch to first gear, my wheels go slower, but ... stronger?

Why would the grinder stall more often at a lower RPM?

#84: Post by **theveterans** » June 9th, 2023, 8:50 am

At high RPM, there's more kinetic energy that translates to less torque required to crush beans. A grinder motor has fixed torque and at a too low of rpm, it cannot provide the necessary torque to crush beans thus stall

#85: Post by **Jonk** » June 9th, 2023, 1:10 pm

There's one grinder that can actually switch gears: https://weberworkshops.com/products/hg-2

But variable RPM grinders are not analogous to fossil fueled cars.. AFAIK some DIY options actually decrease torque together with lower RPM, compounding the problem.

#86: Post by **malling** » June 9th, 2023, 2:49 pm

The Coffee Chronicle just tested it and said 220-240v only had minor stalling issues at 600-700rpm with light roast at espresso with stock burrs, no stalling with SSP. This is probably caused by the feed rate of the burrs. If true the 220-240 version it's a none issue.

It definitely looked much more positive except some mess and static at high rpm... Might be worth the wait to see if they do a 83mm iteration of this.

#87: Post by **DaveC** » June 9th, 2023, 3:34 pm

epoon2 wrote:Hi all,

From what I know from gear boxes or basic physics, when I achieve lower RPM, my torque should be higher right? It's like a car, I switch to first gear, my wheels go slower, but ... stronger?

Why would the grinder stall more often at a lower RPM?

When you reduce the RPM on a brushless motor (no gearbox) typically used in grinders, you reduce torque....with very low RPM it's significantly reduced. The direct shaft driven designs are cheaper and easier to construct, but do have this problem.

In your car when you switch to first gear, your engine is going fast, but the wheels are going slow...because of a gearbox. If you look at a fossil fuelled engines torque curve on the internet, you will find it peaks at higher rpm.

#88: Post by **theveterans** » June 27th, 2023, 6:49 pm

Not sure if Hoon Received the latest revision, but during his live streaming yesterday from this post which is now unlisted/removed from his YT Channel, he had a DOA which he blames on rough shipping. Was looking forward for the A/Bing with the P64, but didn't happen unfortunately. I'm also not even sure if he received the right voltage (110V)

#89: Post by **malling** » June 28th, 2023, 4:05 am

The issue should not be there anymore, Lance took it up in his massive video about 64mm grinders, he said new units ship with a new board that was causing the issues.

#90: Post by **Sproyo** » June 30th, 2023, 9:25 pm

I have the new control board but the stalling hasn't changed at all. Same sentiment on the fb group.

I still really like this grinder but if variable speed for light to medium light roasts is important to you then you may want to look elsewhere.