2 piece hammer foundation

[joe elliott]

hammer fountation.PDFHello, although I’ve been a member of this great site for some time I’ve never posted before. I have set up maybe 10 hammers throughout my 35 year career and most recently (6 or 7 years ago) my 4b Nazel. It’s been difficult finding info about this. I have read many of IFI post regarding this subject and thought I’d threw my 2 cents in hoping to help others who are installing two piece hammers.  Besides the obvious concerns of enough padding (concrete, rebar), keeping anvil and hammer pad level, not running out of stoke distance,  I had an anvil that needed to go about 30” below grade. This particular nazel anvil had an additional 4000 lbs cast to the bottom making for a very tall base.  The “tub” for housing the anvil base needed to be 40” long 26” wide and 36” deep. After much head scratching on how in the world am I going to keep this tub from floating out as the concrete goes around it I came up with putting a 3/8”plate (48” x 36”) in the bottom of the hole and attaching it with ¾” x 1 ½” straps to the sides of the tub. Because the volume/weight of the concrete from plate to bottom of tub was more than the volume of the tub it would have plenty of mass to hold it down if all welds were sound. I spanned the hole with angle iron secured it to the floor…. bolted and welded all mounting tubes to rebar and angle iron. This allowed me to make sure everything was plum and level before filling the 9’x4’x10’deep hole with 24 yards of concrete. It worked great and wish I had taken pictures. I also came up with a mounting tube with a “floating” nut in the bottom. I thought this would be better than the usual anchoring system giving me the possibility of replacing a bolt should it break and a little more “fudge” room for installing. I will try and attach a pdf file of a quick sketch to help explain some of this

[nonjic]

Hi Joe, Looks like a good solution. On the last big one I did we did 2 concrete pours, the first one to the base of the former (ie, the anvil seating level) - then put in the former for the anvil pocket, and the second pour up to floor level. Tied together with some rebar. The hammer hold down bolts went right down into the first pour. Very un-likey to have issues with it in my lifetime ! as you have found very difficult to prevent lift on the anvil former if you go for it in one pour. I knew of a large drop hammer that was put in a couple of decades ago and they tried to do it in one pour *, the former lifted about 3", lop sided, even with dozens of tons of dieblocks holding it down, they were grinding the concrete level for weeks :) (and the gaffer at the factory poured water in the hole every time they said it was level to prove it wasn't!!) * not me, and not my design :lol: