You can create a group of the names you want to see to group them together and see their combined totals.
Or if you mean to filter by hammers, then you can create a set (right click on your dimension - choose create set - add all the hammers). Sets are easy to use as filters - just drag them in and out of your filter shelf as you please.
Finally you can create a calculated field using function like contains:
iif (contains ([FieldName] , "hammer"), "is Hammer", "no Hammer")
and then filter on Is Hammer or the other depending on what you like.
Set are the most precise, but also not flexible enough to pick up different hammer types appearing automatically.
Hope that helps,
Thanks I will try this!