I get new basket yesterday and was wondering what is the differences between them. I know the size is quite different but what about the hole stamping? Are they all the same size, numbers, pattern, etc?


Bottom left is "sold as" LM double, upper left is "no name" triple, upper right original Rancilio double, bottom right is original Rancilio single.

In attempt to determine the number of holes, I grabbed my camera and made pictures of each one so I could print it and easily count them. My first surprise was to discover that hole stamping matrice was quite different from one model to the other. Even the original Rancilio single and double are different.

Let's look at the Rancilio single first. Holes are aligned on the same horizontal and vertical axis. Spacing is 1,5 mm c/c (both directions), 293 holes total. The back of the plate is flat, holes are countersunk to a final unknown diameter. 3 pairs of holes are connected together by means of channels stamped on the back plate (look at the center holes).


The Rancilio double has the same pattern and spacing as the single. 464 holes total. The back of the plate is flat, holes are countersunk to a final unknown diameter. Many holes are connected together by means of channels stamped on the back plate, I would say 2/3 of them (difficult to count). This connection definitively has an influence on the pouring of shots.


The "sold as" LM double has a different pattern. Holes spacing is 1,667 mm c/c, rows spacing is 1,5 mm c/c, and staggered, 557 holes total. The back plate is embossed on an equilateral pattern that provide hexagon countersink around hole. The countersink diameter seem much larger than the Rancilio. I guess the flute shape of hole outlet should expand the water drops and make them connecting together.


Finally, the triple basket has the same pattern as the LM double.and spacing is the same. Holes count is 689 total. The back plate is flat, the countersink on each hole is really small in diameter, even smaller than the Rancilio. The expected connection between water drop is less evident with this model.


So, my next question was: How does the different patterns affect the water flow and How could I measure it?
No an easy task for my knowledge and I still have no idea how to do it. I know for sure the flow must be centered during a perfect extraction. This is visible with naked portafilter. But the interaction of coffee ground is sometimes influencing this path. Pressurized water passing through the basket would also influence the path. So I decided to simply pour the same volume of water at atmospheric pressure and see what happened.

The results are visible in the following videos. I used 2 ounces of cold water to fill each basket. One interesting thing is about the triple basket. Even though the other baskets gets almost empty after the tests, approximately 1 1/2 teaspoon of water remained in the triple each time I made the test. I believe this one need some minimum pressure to pass the water through. It's kind of pressurized.

Rancilio single:


Rancilio double:


LM double:


Triple basket:


Interesting, isn't it?

Every comment are welcome.

Deny

Well I guess this may show a bit why I always have a 'soupy' puck on the triples. It looks like that the triples have less 'dribble drain' than the other baskets.

But the question comes back to how does that change the flavor in the cup given that you put the same dose and pressure time on to the grounds in the basket.

-Cecil

My first reaction is wow! Nice collection of data and videos. I have no amazing insights to offer other than I think I have the exact same collection of baskets and I prefer to use the LM double on my Silvia typically with a dose around 15.2 grams. The stock double is ok but at my preferred dosing there is too much interaction of the puck and screen/screw. The single I've not messed with more than once or twice. I don't really have a proper tamper for it and I would need to experiment with dose and grind a bit. The triple seem silly big to me but I guess those big doses are in vogue now for the popular blends. I guess really I'm just trying to keep it simple and stay with one basket until I get everything else down well.

On my old E61 box, the Tea, I found that the LM basket blonded more slowly than the Faema baskets (which had the plain, 90 degree hole design), and I preferred it for regular sized shots. However, I haven't used it for a while, so I don't know if this effect is true for other machine and grinder combos.

The research on this holds that the hole pattern makes little difference. The holes are smaller than the regular particles but larger than the fines. As such, they are supposed to have no effect at all on the flow. Instead, the aggregate of fine and coarse particles in the puck are supposed to do all the work.

There are certainly big differences in the taste of different baskets because of their different shapes. A conical basket will require a coarser grind than a cylindrical one when making shots of the same weight. A deeper basket allow more water to pool above the puck, and this makes an important difference on some machines.

I've been frustrated so far trying to do experiments on basket shape. It would require a set of custom made baskets, so one could study the possibilities one factor at a time.

If any manufacturers are reading this -- I'll give you a big plug if you make me a set of custom research baskets.

I am taking a guess here but I would be willing to bet that pressure or temperature would swamp the hole size and pattern shape of the basket as far as taste in the cup.

But if anyone takes Jim up on it, I am willing to let his tasting be the judge.

-Cecil

I hate to bring this up, but since it seems as if you have some time on your hands....

One of the things that I always do when cleaning out a basket out of habit, is to gently press, upside down, the pattern of holes against the flow of a faucet. Effectively forcing the water through the screen created by the holes, from the bottom of the basket back through, unclogging any potentially clogged holes.
Some baskets make a nice little shower, somewhat conical in shape, some make a laminar shower, and some have a 'tilt' to them. Fifteen or twenty degrees off of vertical, and the direction follows the rotation of the basket, i.e., as I rotate the basket, the 'tilt rotates with it.

Does it mean anything? I dunno. As Jim said, to really do any tests it would take a lot more time and effort than I'm willing to take away from my coffee drinking.
But you did start it!

what was interesting for me was the duration of the videos and the time it took for the basket to drain.

the single was 20 seconds.

the doubles were 9 & 10 seconds.

but the triple took 23 seconds.

i recently started thinking about baskets and the influence on the shot. i was using the standard faema type double baskets using a 20g dose. i would get a deep screw impression from the group screw. i often got a dead spot in the flow in the center, i assumed from the screw being there. the espresso would flow as soon as the pressure reached full pressure. basically i was up dosing in a smallish basket.

i switched to the synesso "big double/small triple" ridgeless "jonr10 basket" same dose - 20g. i had to grind finer to get a similar extration. the screw impression is very minimal due to increased head space. no more center dead spot anymore. and now the pressure will reach full pressure and the espresso will flow about 1-2 seconds later at about 8-10 seconds after starting the pump.

makes me think about head space being a sort of ghetto ass pre-infusion type of effect. now i am basically downdosing in a larger basket, same 20g dose though.

the espresso tastes a bit smoother and rounded, better tasting for sure.

not really sure what my point is though. thanks for your time.

jon

CRCasey wrote:Well I guess this may show a bit why I always have a 'soupy' puck on the triples. It looks like that the triples have less 'dribble drain' than the other baskets.

I guess you are right about the dribble drain on this triple. Does all triple has the same hole design as mine? One should post pictures to compare.

Psyd wrote:Some baskets make a nice little shower, somewhat conical in shape, some make a laminar shower, and some have a 'tilt' to them. Fifteen or twenty degrees off of vertical, and the direction follows the rotation of the basket, i.e., as I rotate the basket, the 'tilt rotates with it.

With naked PF, if one makes comment based on what he sees under the basket, the judgment may be distorted 'cause shower shape of one particular is different than another.

Just think about garden hoses nozzles. Outlet size remaining constant, water pressure as per faucet capacity, variation of the inlet part change the water jet shape from narrow and far to wide and close.

Would it change the taste? I don't think so as long as pressure, dose, etc, remain the same. If one try to compensate the variables based on what he see, yes it will.

lgxiii wrote:With naked PF, if one makes comment based on what he sees under the basket, the judgment may be distorted 'cause shower shape of one particular is different than another.

I think that there may be a bit of a language barrier leap error happening here. First off, when I say 'shower' I mean that there are multiple streams of water that do not coalesce into one stream, vis-a-vis a bathroom showerhead. Secondly, I was specifically referring to the effect of holding a basket, sans PF, under a faucet, upside down, pressed up against the faucet to force water through the basket.
Unless I completely misunderstood your comment.

I use the Rancilio double basket most of the times and also have a triple which has a very similar pattern (with no connection between each hole). When pulling shots, I found the flow pattern is quite different between double and triple, although the taste from the triple seems to be better -- longer lasting crema and taste not as harsh.

Here is the triple shot :



Double shot :



I haven't had the LM double basket which I guess is ridgeless. Some other websites promote it as being able to make better espresso, like this one :

http://www.jetblackespresso.com.au/shop ... ridgeless/

Does it really help to fit in a tamper better, thus enabling a better shot?

Would a viscous liquid flow at a different rate through a filter comprised of simple cylindrical channels than it would through a filter comprised of channels that opened out like the bell of a trumpet, if the total effective filter hole diameter on the near (in) side of the filter were the same and everything else were identical?

timo888 wrote:Would a viscous liquid flow at a different rate through a filter comprised of simple cylindrical channels than it would through a filter comprised of channels that opened out like the bell of a trumpet, if the total effective filter hole diameter on the near (in) side of the filter were the same and everything else were identical?

If we called the image on the left example A, and the one on the right example B, I would guess that the expansion area in the bottom hole would allow larger bubbles to be formed in the crema, which would tend over time to merge and dissipate depending on the oily surface surfactants of the bean and roast in question.

In example B, I would expect a much more turbulent outflow in the area of each hole, and this would induce micro mixing and a more emulsifying effect of the gases in the outflow. As smaller bubbles would take longer to recombine I think a longer lasting crema would result.

This is only a guess based on basic physics, so YMMV.

Once again a long test period would be the only way to get a result, unless there was a obvious taste difference.

-Cecil

timo888 wrote:Would a viscous liquid flow at a different rate through a filter comprised of simple cylindrical channels than it would through a filter comprised of channels that opened out like the bell of a trumpet, if the total effective filter hole diameter on the near (in) side of the filter were the same and everything else were identical?

I don't think the liquid flow rate would be different from one or the other. I would say the way it comes out of the basket is quite different. One can see the difference in the videos posted by cksaurus (btw, thanks for it). In my opinion, the fact that the outside hole diameter in example A is larger than example B, makes the side of each hole closer together. This tends to collate the stream together and help to produce this beautiful streaming cone in the center of the screen.

Does it change the taste? I would say, not really. Until the barista's judgment is concentrated on the perfect streaming cone and makes some changes in distribution, dose, etc... When I compare both videos, I would say the double shot is more uniform than the triple. But cksaurus says the triple taste better!

A good looking shot does not a tasty shot make.

I have had some very nice looking shots that tasted like battery acid so dont get to caught up in how pretty the shot looks but concentrate on how it tastes.