greg
User
 Baby cino
| Posts: 5 |   |
|
Re:Tamping: How hard?? - 2007/09/21 23:46
The figure of 30lb (13.5-15kg) of tamp force is bandied around as a bit of a magical figure. There's nothing magic about it, and I know of some who get great extractions with more and less pressure than that; but it's probably a good place to start.
Grind some coffee into the filter basket, rest the portafilter on a set of bathroom scales, zero the scales and then tamp until you hit about 15kg. That'll give you a rough idea of the sort of force to aim for. From there you can adjust your grind and tamp according to what suits your palate and what the bean age / type demands.
The clicker tampers and others like it give you an indication of when you're at a certain pressure; however that preset pressure isn't right for everyone so they're of limited value if you want to use a different pressure. As Espress Yourself mentioned, you're trying to create a uniformly packed puck of coffee so you're presenting uniform resistance to water flow, and thus ensuring the water travels evenly through the coffee rather than taking a shortcut and blonding prematurely. This is commonly referred to as channeling.
One good way to avoid channeling and premature blonding is to get a tamper that's exactly the right size for the filter basket as this will tamp the coffee right to the edge, rather than leaving a point of low resistance around the edge for the water to escape through. This also means you only have to do a single tamp rather than two or three (or more!). Not only does this reduce frustration immensely, it eliminates the chance of getting two layers of tamped coffee which would create a point for channeling to develop, which is something that can happen when doing multiple tamps. Plus, it's a lot easier to repeat one tamp exactly than several. Seems obvious when you think of it, but it's surprising how often this gets overlooked - apart from being cheap black plastic, factory tampers are often a good 2-3mm smaller than the filter basket, and even with a typical 58mm tamper you'll often find many filter baskets are closer to 59mm.
Whenever possible, Pullman Tampers are made to fit the customer's filter baskets to a fraction of a millimetre to ensure best results by addressing the above points, and when not possible we normally still supply tamper bases larger than 58.0mm. We can also supply top quality filter baskets fitted to the tamper if necessary. Pullman Tampers are available right here at whereismycoffee in a range of attractive woods, and I'm sure Gloria and the team can arrange for us to supply filter baskets if your machine takes a decent sized 58mm basket and you want to go down that path. Not only are they hand-made, precision-made and a work of art, they're also a stack cheaper than the clicker tampers! If you're not sure if they're worth the money, have a read through www.coffeetamper.com.au/testimonials.html and read what others have said.
Good luck!
Greg
Post edited by: greg, at: 2007/09/21 23:55
|