Will powerhammer crack slab?

[chief mcgee]

Will powerhammer crack concrete slab?
Getting ready to pour the slab for my shop. I am worried about my 100 lbs. powerhammer cracking it. Is 4” of concrete enough? Or should I go to 6” thick? More money. I have some ½” thick rubber conveyer belting I was going to use under the hammer. Say 4 layers. That would give me 2” of cushioning.
Also thinking of using the concrete with the fiberglass threads instead of the reinforcement wire.
Thanks for any thoughts. Chief Mcgee

[m_brothers]

Concrete??? Or Rubber Flooring

[Candidquality]

For some reason reading that I am thinking 12" at a minimum. Can you tell me the weight of the hammer itself? I'm sure someone here will know for sure. Can depend on the soil compaction in your area as well.

Btw, this is for the area immediately under the hammer only. The entire shop does not need to be that. Just make sure of where you really want it. pour it under and 6" to the outside and then put in a break yourself. should really cut down on the vibration to the shop.

[Mike Turner]

Your power hammer should have it's own footing poured separate from your floor slap. This will isolate the vibrations. If it is a Little Giant I think Sid has footing info on his website it is a little over kill but worth the look.

[HWooldridge]

I have a cubic yard of concrete under my Beaudry and it is solid as a rock. A 25 lb hammer isn't bad on a 4" slab but anything bigger is marginal.

[Valentin]

my power hammer sits on wood 25x25 mm thick and the floor has no crack ... and my normal anvil has cracked the floor from the sledge hammer

[jeremy k]

chief mcgee - Just for instance, The Little Giant 100lb hammers recommended foundation plan is 39" wide x 58" long x 36" deep. The recommended shim between the hammer and the concrete is - 3/8"-1/2" cork or rubber belting. When I figure out the exact spot my 100lb LG will go - it will get a footing like that. - JK

[Bentiron1946]

I was in a shop that had a 4" slab and a 50# LG and after six months of pounding the entire floor had hairline cracks. After another six months the entire slab was being replaced. If you only do ocassional forging you may get by with putting your hammer on wood but if you are a production shop I strongly suggest that you have a seperate foundation for the hammer.

[Ten Hammers]

My 30 # Kerrihard sets on pieces of bridge plank ( 3 "thick and I guess 8 "wide each ). Motor is mounted on the plank as well. Jeremy has a good idear with the spec'd plan for the footing.

[welder19]

Make sure you go with 4000 lb concrete and use rebar and wire under the the area the hammer will go, wire and rebar is cheap and either make it a seperate footing or cut a break around it but probably the best would be it's own footing 24" deep, poured prior to the rest of the floor and then put expansion joint around where the rest of the floor will pour up against it.

Just my opinion, I havn't too much power hammer experience but I do have a bit of experience with concrete.

welder19