I have been using the MyPressi for a while and have been trying to perfect my distribution and tamping technique. But I still seem to have side channeling on most shots, no matter what technique I use. Currently I use a 53mm stainless tamper I picked up from Sweet Maria's, but have been wanting to get a nicer one. With the Holidays coming up, what better time.

I was going to purchase a Reg Barber with the US curve (since my other is flat), but wanted to see if anyone knew the best size base to purchase. Should I go with the 53.0mm or would something slightly smaller or larger be better. The Reg Barber's on the MyPressi site all have a flat bottom, which is why I wasn't going to purchase there.

I realize that a tamper won't solve my technique challenges, but it might make them a bit more interesting.

Vince

When I got my Twist, I already had an aluminum RattleWare 53 mm tamper from my DeLonghi pump-toy days so I just used that. I wouldn't go any larger, as the tamper I have does not even hit the bottom of the basket due to the flared sides, but I wouldn't imagine that you'd want to go any smaller either. I think 53 mm is about right.

The tamper shown below is in the stock MyPressi Twist basket, shown next to a generic 53 mm Saeco basket for comparison. The tamper binds at about the same depth in the Saeco basket as the MyPressi basket.

Thanks for the help yakster. I assumed that 53mm would be right, but wanted to make sure that someone hadn't tried a different size with better results. Now if I can figure out how to get rid of the side channeling, life would be good.

Thanks again,
Vince

Vince,

Side channeling and spritzing is pretty common with the mypressi, though if it's minimal it shouldn't affect shot quality much. Here are a few tips which should help solve the problem:

1. Use very very freshly roasted coffee. Probably should go without saying. I find the ideal rest time is about 3 days, more for lighter roasts, less for very dark and oily roasts. In any case, the staler the coffee, the less binding you'll have during shots.

2. Downdose and make your grind finer. If you are using 19g for example, try 18g at a finer grind, one that pulls a double in 35 seconds +/- 5 seconds. Personally I find the optimal dose size for a double to be 18-18.5g, but that obviously varies according to roast and taste.

3. Use a toothpick or large paperclip and stir the coffee around vigorously to remove any sign of clumping. In order to avoid having the coffee spill when doing this, try grinding with a funnel inserted in the basket. I cut the bottom out of a Jello pudding cup and that fits perfectly. It works great at keeping all the coffee in the basket both when grinding and stirring.

4. Remove the funnel and then use the "Stockfleth's move" to even out the distribution before tamping. This amounts to little more than running your index finger around the rim of the basket to make the coffee even. Here is a video of the technique, which I think makes a bigger deal out of it than it really is. But it's still useful:

Stockfleths Move for Dummies [video]

5. When tamping, start with a roughly 5 lb tamp, then twist the tamper a few times. Inspect the level of the coffee to make sure it is at the same height all around. Then tamp at 20-30 lbs and twist again.

Hopefully this will help get rid of the channeling.

Dom

Dom,

I think I'm going to try your advice on down-dosing the basket. I've been using mostly 18 g with the Twist but have noticed spritzers with the shorter, generic 53 mm spare baskets I just received. I'm thinking a smaller dose in the smaller baskets may help.

I could try the WDT or "Stockfleth's move" as well, but I haven't been finding this necessary with the stock basket, though I do nutate before tamping.

I've really been impressed with the quality of the espresso from the Twist. The crema is always very thick but it is so much easier to get the full extraction and tiger mottling with the Twist then my lever which is much more finicky and requires careful pre-infusion on a double to get similar results.