I use a dosing funnel (the short one) from Orphan Espresso. I have a 58 mm flat tamper. I'm using the double basket that came with the machine, and it's ridged. If I tamp normally, I get really bad side channeling (evident when using the bottomless portafilter). I've noticed that if I put a dimple in the center of the coffee before tamping (using the handle-end of my tamper), it pushes the grinds outward, and I've significantly reduced the side channeling. However, I'd rather fix whatever technique (equipment issue) that is causing this.

I've considered switching to a convex tamper, but I haven't seen a lot of info to indicate that will fix it.

Is the dosing funnel causing this? I really like using it, because my counter stays pretty clean. I think I'll try a ridgeless basket tomorrow.

Thanks.
Jack

Like yourself, I use the Orphan dosing funnel. If I create a dimple when using a higher dose, side channeling is eliminated. If I use a high dose without the dimple, channeling is pretty much guaranteed on my machine. With a more moderate dose I don't need a dimple to prevent side channeling. I get these results whether using a funnel or not.

Not sure if this machine dependent or operator error, but dimpling certainly helps to eliminate side channeling when updosing.

I switched to a convex tamper and a VST sized c-flat. Both have virtually eliminated side channeling without potentially causing another problem (dimble in the middle will cause distribution to not be even).

The people that argue there is no difference between a flat and convex have much better luck/skill than I do.

When using a dosing funnel or similar apparatus, you could give the portafilter a whack to settle the grounds to the corners of the basket (helped me).

The HG-One tumbler is sorta like a dosing funnel, so this might help. I hold the tumbler and PF and give them a circular swoosh once or twice, until the grounds settle in the basket a bit. The HG-One leaves a big fluffy pile and this settles them pretty well. Use BOTH hands.

After that I use mild angulating (or is there a better word?) and a very tight tamp base. If I'm too aggressive with the angulating I notice dense pockets of espresso around the edge of the basket after the pull.

The dimple idea sounds interesting, sounds like grilling burgers! I wonder if a tamp handle would make a nice dimple...

BTW Jack- which grinder do you use? Is the basket that came with your machine pretty straight walled or does it taper? Just curious.

I'd suggest when you're dosing from your Forte, make sure grinds fall into the corners of the basket first. After you circle the basket or PF handle around to get them in the corners...you can let the rest fall into the center.

I find that it's pretty hard to fix any distribution issues by tamping no matter what technique used (nutate, curved tamp, etc). But if you get the coffee in the right place as it's falling, usually everything works out. This is assuming we aren't talking about the HG1, as that requires a different technique for me, grinding into a pitcher or cup first.