Getting a Precision Basket from IMS

Recommendations for buyers and upgraders from the site's members.

#1: Post by daris98 »

Hi home barista-ers.

Recently I bought a Competition-grade IMS basket for about 27 USD from a local distributor. The exact model can be found here:

Now, I know that I probably made a stupid decision as I should have asked here before I pull the trigger. But I have it with me now, and I can't refund it... Silly me. Here's the picture of the basket:

So as I can't refund it, I decided to explore and hopefully get something out of it. I know this probably shouldn't be in the "buying advice" as the item has already been bought. But I am still looking for options.

I have been brewing espresso with my Flair 58x for almost a year now, and being honest I think I'm happy enough with the espresso I'm getting. The espresso has been balanced in terms of clarity and texture. Then I somehow stupidly ended up buying a new basket expecting to get something better out of my 58x. Upon reading a few tutorials and discussions (including in home-barista) I was informed that "precision" baskets has more uniform holes and therefore should lead to more even extraction.

But then I thought a couple of things that made me more confused than ever before:
  • How can one tell whether or not a basket is "precise"? Is the Flair 58 stock basket a "precision basket"? Maybe someone here have tracked down the origins of the Flair 58 stock basket or analyzed the holes through a microscope. Is there such information on the internet? If it really is a precision basket, that means I was just wasting money into one of these IMS baskets :shock:
  • I have yet to test it side by side with my stock basket. Before I test, I want to ask here first if there's anything I should chase for with a precision basket. Is it just that my shots will be more consistent throughout the day, or can it actually provide better, more uniform espresso? I have read somewhere that it doesn't change the flavour of the espresso, but it can amplify it. Is this true?
  • I have heard that there will be differences of "flow" from different baskets to different baskets depending on how precise and how big the holes are in the basket. From what I heard some baskets are "high-flow" and others are "low-flow" depending on the size of the holes. Have anyone here any idea what "flow" my particular basket is? I am also interested on the effect of flow to the type of coffee and the grind size that I should use. I read somewhere that some baskets are geared towards brewing lighter roasts and others for darker roasts. How can I possibly test this for my new basket? And speaking of grind sizes, will there be an effect?
Sorry for the long question, but I want to explore this deeper. Looking forward to your answers...

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#2: Post by Jeff »


B68 -- 68 mm border, typical for 58 mm baskets
2T -- Nominally a 2-cup basket (tazze)
H24,5 -- 24.5 mm tall

There was a time when machines commonly shipped with stamped baskets into which holes were stamped. Depending on the luck of the draw, a stamped basket might have reasonable uniformity of hole size or not. "Precision" baskets generally refer to making those holes in a way that tends to be more uniform. From what I understand, many manufacturers are shipping baskets made in that way as stock. Now that the baskets shipping with machines are often more uniform, there isn't anything specific to be gained (or lost) from going from one good basket to another.

Not all precision baskets are the same. Even with IMS, there are several tapers of the basket and hole patterns. Different hole patterns (count, size, spacing. how close to the edges, ...) are one of the factors that can make a basket tend to faster flowing shots. All of those variables add up to "baskets are different". There really isn't a formula or method I know to say what changes you need to make between two baskets. You dial them in. You may like one over another for a specific coffee, water, ratio machine, and extraction profile.

Chase what you always chase -- good espresso with what you have in front of you.

daris98 (original poster)

#3: Post by daris98 (original poster) »

Thanks for the comprehensive answer! I think the main takeaway from your answer is that you can't tell the exact difference of results because all baskets are somehow different. I'll go and experiment myself, first with the same coffee and then I''ll be trying different roast levels and origins. I'll keep you updated once I have a satisfactory result.

Supporter ♡

#4: Post by PIXIllate »

A physical basket comparison I did a while ago:
Basket Comparison (EPHQ, VST and OEM) - Added E&B Superfine

daris98 (original poster)

#5: Post by daris98 (original poster) » replying to PIXIllate »

This is what exactly I'm planning to do! I'll share the results once I have the time.


#6: Post by benhb »

Changing from a stock basket on a manual lever machine (ROK) to an IMS competition/precision basket, I noticed flow increased significantly.

Shot times for the same ratio brew recipe had dropped from 28-34 seconds to about 18 seconds (+/-1). So in my experience, flow is much higher on (an IMS) precision basket. But consistency increased as well. Shot times seemed to coalesce around 18 seconds instead of varying a fair amount.

I wasn't at all expecting this huge a difference between baskets. My goal in buying a precision basket was only to eliminate this one variable (a "standard" machined basket with potentially inconsistent hole sizes/shapes, slightly convex shape and prone to bending under pressure) that may or may not be adversely affecting my shots. I didn't expect shot quality/enjoyment to change to such a degree as I had seen several videos/articles/posts about baskets having varying or unnoticeable results. Nor did I know flow would increase so much. At first I was mildly horrified my shot times dropped so much, thinking I'd taken a big step backwards. But, to my surprise, the results have been better.

This is very subjective but taste wise I notice less "edge results", i.e. a lot less sourness & a little less bitterness (in the same shot). (Bitterness wasn't a sizeable issue on my manual machine, but acidity/sourness was in early days.)

I've tried to rationalize how/why this works and my current theory is that inconsistent holes cause inconsistent flow/extraction rates from different areas of the puck. High flow areas get over-extracted, low flow areas get under extracted. The result is (confusingly) both bitter and sour.

The precision basket reduced this sour/bitter combo noticeably. Especially the sour.

Anyways, looking forward to hearing about your results with your new basket on the Flair 58.

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#7: Post by Jeff »

Rationalization is covered pretty well in readable form at ... -espresso/ (Cameron's blog) and less digestible form as the paper at ... 19)30410-2

Basically, by getting away from "highly clogged" in the puck and moving into a higher-flow one, one can reduce shot-to-shot variability. Although the "paper" talks about the commercial benefits, there are lessons to be learned, considered, and explored for home baristas as well.

daris98 (original poster)

#8: Post by daris98 (original poster) »

Hello, thanks for the response @benhb and @Jeff. The article from Strive for Tone was great! Especially for a beginner espresso maker like me.

The reason why I'm back here is that I am with a quick/preliminary testing result. I kept the grind size, dose (18gr), and pressure (8-10 bars) the same for all my brews, and used both baskets sequentially (one after the other). I noticed that the brew got similar results in terms of beverage yield and time. My OG flair basket produced 42.3 grams in 29 seconds, while the IMS produced 42.7 grams in 30 seconds. But, upon tasting both, I felt like they are two very different tasting drinks. The OG basket produced a brighter espresso with some notes of bitterness. The IMS one was more flat, but sweeter and more "predictable". Though, I am still not sure whether my taste buds are reliable or not as I had never trained myself to differentiate espressos. What I am sure though is that both shots are different and I preferred the IMS by a significant margin.

By reading the findings that @benhb found, comparatively, I was not able to reproduce the "faster shot flow" but I was able to produce the shot that I think was better. But I still have a few questions that I feel needs to be answered:

1. Is my methodology sound? Do I have to modify some of the things to get a more "reliable" result?
2. For replicability/consistency purposes, do I need to test more than 2 times, and if so, how much would you think would give a "fair" result?
3. I have to admit that I don't have the necessary tools or skills to conduct an experiment like this. Cashing $500 for a TDS refractometre or training myself to be an espresso-tasting master is kind of unrealistic, do you have any suggestions so that these limitations don't act as a roadblock for doing something like this?

Looking forward to your answers!

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Team HB

#9: Post by Jeff »

My personal opinion is that the shot-to-shot variability on a manual lever is going to require a lot more than a couple of shots to come to any meaningful conclusions about reasonably good baskets or even grinders.

How many is enough? I don't know how variable your technique is and how well you have other variables under control. Ten? Fifty? More? I find the number to determine if I there is a significant flaw in the result I get with "gear X" can be reasonably small. If you're asking me to differentiate between two things that are similarly good, it will be dozens of shots or hundreds. That's without throwing in the variability of a manual lever. That variability is great for getting good to excellent shots every morning, but not so good for testing things around it.

Take notes on all of your shots. I find that writing them down helps me internalize them. On a conventional pump machine I would include the coffee type, processing style, and roaster at the top of the page. Each shot would have dose, grind, output weight, and time, as well as some flavor notes. I'd mark the input I changed with a box around it. Even "Yuck, really bitter" can be enough. You might find some patterns related to baskets. More likely your skills at dialing in will increase faster with greater attention to changes and outcomes.