G-Iota DF64 / Solo / Turin Review

Introduction

Availability and price:

First impressions:

General information:

Italmill 64mm flat burr (stock burr, non-coated)
Original packaging of the grinder

Performance:

  • Espresso: 18g out in 13 seconds (add to this a few puffs with the bellows, roughly another 4–5 seconds)
  • Pour over: 18g out in 8 seconds (same thing, add a few seconds for the bellows)
  • Method 1: Do the marker test on each of the 3 orientations and compare the results, picking the one that has the least amount of ink remaining: using a dry erase marker, paint the outer flat areas of the top burr, then place the carrier back and tightened the adjustment ring almost all the way. Now, slowly tighten it further rotating the bottom burr with your fingers by spinning the central bolt. When you first hear gentle friction, stop moving the adjustment ring and just spin the burr a few times around. The goal of this is to erase the marker at the point of contact, therefore determining the burr alignment. Now, fully remove the adjustment ring to release the carrier and observe the results, take a picture if needed. Repeat the operation for the 2 other orientations and set your grinder with the one achieving the best result. Using this technique, you can also align the burr by placing aluminum shims under the burr to raise the area that is not touching. I recommend following Thomas Greene tutorial if you are not familiar with the process. If you decide to do this, be aware you could very easily make things worse (which is why a lot of people would recommend you not to touch it). I have personally added one folded aluminum shim under 2 of the 3 available areas (small areas right behind the screws, which are levelled with the holding ring going all around the carrier).
  • Method 2: Dave recommends to “clean your grinder, find the first glide point that you can feel (note which mark on the dial it’s on), then move to the loose point and move the burrs backwards and forwards tightening down the adjuster until you feel the second rub. Note the mark you’re at now. How many marks difference between them? Then repeat the above for the other 2 different positions of the top burr carrier and choose the position with the smallest difference. Mark the carrier, so you don’t forget.”
Highlighted areas show where to place shims when aligning the top burr. Picture also shows empty space behind the top burr where some of the retention occurs.
Once you have found which orientation of the top burr carrier is best aligned, make sure to mark it!
18g in at setting 9 (espresso range)
DF64 Extraction on Flair Pro
Grounds at espresso range with stock burrs
DIY WDT tool
How to find your burr touching point (I recommend to unplug your grinder first)
My touching point is roughly -5
How to access the burrs to clean and/or replace them

Accessories:

Notes:

  • If you want to improve your extraction, distribution is key. Yes this grinder does a great job in terms of clumping and grind uniformity, yet I prefer to grind into a dosing cup, giving it a few shakes before transferring the grounds into my portafilter. I then spend some time applying WDT and carefully tamp to create an even and flat surface.
  • If you wish to change the look of the grinder, as per Bella-Barista: “After attempting to remove the carbon wrap and polishing the aluminium, we have discovered this would require a great deal of time and effort and recommend not removing the wrap at all. The easiest option-to change the look is to apply a wrap over the original one.”
  • If you wish to reduce the amount of “wasted” space in the burr chamber, the user “Gampiero” on HB came up with a cheap DIY mod. He found it particularly useful with dark roasted beans. Personally, I did not feel the need for it while using light/medium roast.
  • Some users have had issues with popcorning (very common with single dose grinder: once most of the beans have been ground, there is no mass pushing the rest of them down so the last ones struggle to get caught by the burrs). Personally I haven’t found this to be much of an issue but I talked to the manufacturer and they said they are working on a mod (post #109 here shows an early design): some kind of paddle that would be located below the main bolt and that would push the beans towards the burrs. At the time of this review they were still at the early stages of testing but I wouldn’t be surprised to see the future orders being shipped with it fairly soon, and I assume the mod could be added to the previously shipped units such as mine. Other mod I have came across was posted on a Polish forum, you can see it here on post #523. Also, if you have access to a 3D printer, @Ben-030 from Home-Barista forum has designed and shared these 2 different mods: Option 1 and Option 2. Both works very well to reduce popcorning as well as slowing down the bean feeding rate. Both need to be placed inside of the bellow. (as always, people like Ben share for free their designs for the community, it is not to be used for personal financial gain). Because of the high speed (1400 rpm) of the grinder, a disc mod such as the one we have seen on the Niche Zero doesn’t make sense to me as I can’t imagine any bean would find its way through the hole at that speed, and I think it would also reduce the efficiency of the bellows.
  • On a similar note, if you find you are having inconsistencies in your grind size (for the same reason as explained above, this is common to single dose grinders), you can try to control the rate at which you feed the beans in the hopper. Once again, the same mod designed by @Ben_030 will help you with that endeavour.
  • The retention/dose consistency/exchange of this grinder are all really good, but as always there is room for improvement. After brainstorming from several owners that I have read on different platforms, it seems that so far, Ben_030 has found and designed an easy solution. It will however require you to open up the grinder completely, probably voiding your warranty in most cases so think about it twice before to go ahead. This mod implies removing the two silicone anti-clumping plates and replacing them with the Mythos One clump crusher (I linked HomeBarista Belgium but you can easily find this anywhere, Google is your friend). Because the thickness varies, you’ll need to 3D print this spacer or make one yourself, fairly easily from pretty much anything you can cut to the desired size.
  • If you find the chute is getting too messy and you don’t have a funnel or don’t want to hold a cup right underneath it, @Ben_030 has once again done the work for you and designed a portafilter fork that can be switched with the original one and that will bring your portafilter closer to the exit chute. Same thing here, he lets you 3D print it for free a long as you don’t try to make money with it!
  • Depending on which burrs and which roast you are using, you might be prone to more or less static. Once again, on my side, with light/medium roast and stock burrs, I have not noticed much at all. If you do, try RDT.
  • Because I have only tested the stock burrs, I cannot speak to the efficiency of others, but I believe it is important to note that each of them will bring a different set of pros and cons and I recommend you to inform yourself about what they might be if you are going to purchase them, as they don’t come cheap. More and more users are sharing their findings on forums and social media.
  • I have designed a basic adjustment ring that has markings all around if you wish to print it on a sticker or a vinyl (if transparent you’ll need to change the colour of the markings or you will not be able to see them on the black collar). Here are the .jpeg and .ai file.
Adjustment ring with uninterrupted markings

Pros:

  • Price / Value: getting a 64mm flat burr, single dose, low retention grinder at this price point is unheard of.
  • Extremely low retention, great dose consistency and very low exchange
  • Efficiency / Quality: great results, both with espresso and pour over.
  • Easy to clean: accessing the burrs so easily is highly enjoyable. There is no need for any tools and the whole process can be done within a couple of minutes
  • Simple design and easy to use
  • Well built: all metal, very sturdy; it doesn’t feel cheap at all
  • Great customer service (I speak for Alibaba and The Gluons, but I’m sure the rest of the suppliers are just as good, I simply have not dealt with them)
  • Option to upgrade the burrs to SSP for different particle distribution, longevity, speed... Different burr geometry can open up new flavour profiles and change the body of your brewed beverage, they can achieve different efficiency with different degree of roast etc…

Cons:

  • Exit chute gets partially obstructed at the anti-clump plate when grinding at very fine setting (for espresso). It is completely fine as long as you remain in the same range of setting, as once that “dam” is in place, it doesn’t go anywhere so it doesn’t affect exchange or dose consistency much at all. But when going from espresso to filter range, if I don’t clean the grinder or purge enough beans through it at the new setting, the larger coffee particles, on their way out, cause this “dam” to collapse and therefore come out of the chute, ending up with more coffee out than I put in, and obviously having an excess amount of fines in my pour-over-dose which greatly affects the evenness of the extraction. I wouldn’t recommend to completely open up the grinder (which is the only way to access the 2 silicone rubber clumping plates) as you would be voiding the warranty. Also, try not to stick anything up the chute as you might end up damaging the plates.
  • Wasted space: The retention and dose consistency are both excellent, but if I had to be picky, I would say that some areas offer a lot of potential for grounds to get trapped. One of these areas is behind the top burr ( see picture under “burr alignment” section). Instead of a flat circular area, the top burr is attached to the carrier through 3 individual raised flat areas, leaving a large gap behind it. Since this burr is stationary, one could try to fill up this space or to restrict the major entry point of grounds by reducing the gap between the inner part of the burr and the carrier, for example with some aluminum foil wrapped around the inner part of the carrier.
  • Grind setting indicator not easily visible. On my grinder, the indicator (which is a coffee bean) , is the same colour as the grinder body, making it hard to see. In addition, it is located under the adjustment ring, making it a little awkward to see what setting you are on. You may want to draw a line or a dot on the metal part of the top burr carrier to make it more visible. Once again, I got used to this very quickly and it hasn’t bothered me at all since then. However, you can either purchase this mod from PortaKeeper for $12 or, 3D print it yourself from free designs shared by some owners; If you are interested, check out the mods from GregoryJ (HomeBarista), Strudlez (Home-Barista) and AnthonyTD (Coffeeforums - As per his request, I want to add that he has been generous enough to make these designs public and they are not to be manufactured and sold for personal gain).
  • Adjustment ring isn’t marked all the way and stops at 90. This is a problem because you can quickly end up in an unmarked area to dial in, making it hard to go back to if needed. Same thing happens the other way as the burr touching point is more often than not before 0 with the stock burrs, so if for some reason you need to go extremely fine, you’ll also end up setting the ring in an unmarked area. Finally, when switching burrs, because the SSP are much thicker, your touching point might move to 25 or even more, so when going into coarse setting, you’ll definitely be in an unmarked area. As explained in the last point of the “Notes” section, I have designed a basic file that you can download, modify and print as you wish to counter this issue.

Conclusion:

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