cwilliams Posted October 23, 2010 Share Posted October 23, 2010 Hello everyone, I am in need of alittle advice. I have recently purchased a big-blu 155 and felt the working height could be alittle higher than it was compared to my other power hammmer. So I decided to cut my concrete and dig a foundation and in the end have a concrete platform sticking out of my slab 5 inches tall to place my big blue on. I will probably dig down about 36 inches or so and will also emplace bolts in the concrete to bolt the hammer onto. Does anyone see any problems so far with my plan? Now onto my questions. Does anyone have any photos of the rebar structure they created when creating a power hammer foundation? If not how close to the surface should I allow the rebar to be? I appreciate any advice offered on this subject as I am terribly ignorant in this area. Also any advice on what concrete to purchase, I plan to mix it myself with a rented mixer. Attaching two pics of where I currently am at on this project. PS Yes I used the long drill bit to break up the clay, Its a cheapo harbour freight bit and it worked very well with my cordless drill. Link to comment Share on other sites More sharing options...
JNewman Posted October 23, 2010 Share Posted October 23, 2010 Sounds good but I would price getting the concrete delivered. It is often cheaper buying the concrete that way rather than buying it bagged. For a smaller load like that you would want to get what is called metered concrete around here, the truck has all the ingredients separate and mixes it on site. WAY less work as well. I would get a high strength concrete like is used in sidewalks or driveways go with as little water as possible. When I poured my hammer foundation I had them add fiber to the mix to help prevent cracking and waited 30 days before using the hammer on the new foundation. Renting a concrete vibrator helps with filling the hole especially around the rebar if you use a concrete with a low slump (little water). Rather than setting the bolts right in the concrete I like the method Massey came up with that came in the drawings for the foundation for my hammer, it is more work but has several advantages. Down near the bottom of the foundation you place plates with rectangular holes and boxes around the bottom, you then form a tube to the top of the foundation. You forge t bolts with a section of the shank near the head square. When you go to bolt the hammer down you drop the bolts down the hole and through the square slots. You then place the hammer, you don't have to lift it over the bolts potentially damaging the threads and you have a little wiggle room. You then rotate the bolts 90 degrees and lift them using small threaded holes you drilled in the top of the bolts then put your nuts on. If you ever break a bolt it is fairly easy to replace the bolt. Link to comment Share on other sites More sharing options...
Jamesrjohnson Posted October 23, 2010 Share Posted October 23, 2010 About one year ago, I built a foundation for my Anyang 165… and this is the process I used. I cut concrete foundation about 4” larger than the size of the hammer base. I dug a 4 ft. hole and then used ½” rebar and built a “cage” with rebar about every 12” in all directions. As I went up (vertically), I added rebar every 12”, so there was a lot of rebar… and I welded the rebar as I was laying it out. I also put threaded rod that would extend from the bottom of the hole through the foundation. I welded the threaded rod every 12” to make sure it would not pull out of the foundation. The threaded rod was used to anchor the hammer to the foundation. I also put 1” by 8” cedar next to the original concrete foundation to isolate the new foundation from the old slab. I then poured the concrete level to the original foundation. I needed the hammer to be about 4” above the foundation so I built a metal frame out of ¼” plate, then used 1” plywood between the hammer and the foundation to gain the height that I needed. By doing this, if you ever need to move the hammer, your foundation would be at the same height as the original foundation. The metal frame gave me a welding point for the pivot points for the foot peddle. I called a truck to deliver the concrete. You could mix it by hand, but that is a lot of work and I doubt that you would save very much money… but check out the economics. This foundation mass and isolation made a huge difference in isolating the vibrations from the building. Hope this helps. Link to comment Share on other sites More sharing options...
forgemaster Posted October 24, 2010 Share Posted October 24, 2010 We have made all our foundations as per the massey foundation book. We have never used reo bar, nor did we use very High strenght concrete, the reasons given for this is you are trying to cast a monolithic block of concrete, high strength concrete has the least vibration asorbtion rate, and it also can lead to spalling and cracking due to vibration, use as little water as possible, vibrate only sparingly as this will lead to sepration of the mix and create voids. We now always make the pockets for the bolts, but we fabricate them from pipe and plate for the chamber on the end. If you break a bolt you will realise what a PITA it is to try to remove a cast in bolt to put in a new one. We had to jack hammer down 6" through the conctrete to get a sound piece of bar then thread it and fitted a threaded sleeve with a stud on the top of that to repair our broken bolt. Now I always go for the pockets. Phil Link to comment Share on other sites More sharing options...
BryanWillman Posted October 24, 2010 Share Posted October 24, 2010 Is the massey book that describes foundations online anywhere? Or available used? The "t-slot at the bottom" idea sounds brilliant. (Guess you need to pain the box though - otherwise it will someday rust, no?) I don't know about super deep concrete, but for the foundation for my milling machine, I was told to water it. (12" thick) This makes it stronger. You need just the right amount of water when poured (too wet -> bad), but once it has set (24 hours?) it makes it stronger to keep the top wet. Concrete is pourous, and cures very slowly. But apparently the big return is in keeping it watered and letting it cure for 28 days. By water it I mean literally - you spray it with a garden house, cover it with plastic, repeat every every day for 4 weeks... Link to comment Share on other sites More sharing options...
BryanWillman Posted October 24, 2010 Share Posted October 24, 2010 By the way - couldn't you get some of the same effect by bolting the hammer to have Very Thick steel plate, which rested on some kind shock absorbing material? Link to comment Share on other sites More sharing options...
JNewman Posted October 24, 2010 Share Posted October 24, 2010 I did use rebar for mine and I thought the booklet I got from John at Massey said to use reasonably high strength concrete. I think I used a 25mpa mix the same as used in a sidewalk. We vibrated just enough to get it to flow from one end of the pit to the other and to flow under the formwork for the anvil pit. I did keep the concrete wet for a couple of weeks. Link to comment Share on other sites More sharing options...
Sask Mark Posted October 24, 2010 Share Posted October 24, 2010 Consider using HS type concrete as this will resist the concrete breaking down due to sulphate activity. Vibrating is a good idea to eliminate honeycombing. Just be sure not to vibrate 'too much' as this will cause the concrete to 'unconsolidate'. Additionally, I would use 1/2" asphalt impregnated fiberboard as the isolation joint between the adjacent slab. It is only about $10/sheet. A 1 week wet cure (wet burlap covered with plastic) will reduce curing too quickly and shrinkage cracks occurring. A large mass of concrete generates a lot of heat during the cure. This accelerates the cure and can lead to strength problems. We have cast refrigerant lines into some large foundations in order to circulate glycol to keep the temperature down. When my company pours equipment foundations, we make templates (or the templates are provided by the equipment manufacturer) for the anchor bolt layout. The template sits just above the final level of the concrete. The anchor bolts are usually tied and wired into the rebar cage. The anchor bolts usually have a 90 degree bend at the end or have a large washer on the end of the rod with a threaded nut (spot welded to prevent backing off)holding the washer on. As for concrete strength, it is usually in the 25-30 MPa range, but I can't remember ever doing a hammer foundation that receives numerous impacts. Just remember that the strength rating is usually a 28 day rating. Concrete will continue to harden so, even a 20 mpa concrete will be much stronger than this in a few years. The largest foundation I have worked on is for a spiral welder for a pipe fabricating facility. I have been told of foundations we have worked on in the past where the anchor bolts we 6" diameter and 6' long. Link to comment Share on other sites More sharing options...
Ric Furrer Posted October 24, 2010 Share Posted October 24, 2010 My 3B Nazel is set on 6 bag mix formed to 8" slump and cut back with some product to a 3" slump (or is it the other way round?) at any rate I used what Patrick Nowack said an engineer at his company speced out. I poured it all with rebar and left it to cure for 30 days. Drilled 1 1/8" holes 15" deep and set 1" B7 threaded rod in the holes using a two part epoxy. PROPOXY 300. The holes were vacuumed and then blasted with my power washer as water is not an issue with this epoxy, but dust is. I tripple nutted with locktite and a pin though the top nut. been OK for four years now and I use the 265 weight hammer heavy from time to time. Videos on youtube under 3B Nazel. I was on the fence for a more labor intensive mounting plan, but this worked well. Ric Link to comment Share on other sites More sharing options...
cwilliams Posted October 25, 2010 Author Share Posted October 25, 2010 Thanks so much everyone for the advice, it is truly appreciated. Its alot to absorb so I will ensure to take photos and post here so others can see the direction I took. I like the idea of attaching the welded rod to the rebar structure, which I had not considered before. Thats why I asked, but the pipe with welded in coupling nut sounds appealing also. I will ensure to keep my concrete wet, and will also now call my local concrete company. It might save me the trouble of renting a mixer and getting a pallet of bagged concrete. Bryanwillman No not really, the main reason people use a separate deep foundation is to isolate their power hammers thumping from the main shop slab. Therefore hopefully keeping the slab from cracking and or knocking things off shelves and or abusing the structure. Chris Link to comment Share on other sites More sharing options...
Sask Mark Posted October 25, 2010 Share Posted October 25, 2010 My 3B Nazel is set on 6 bag mix formed to 8" slump and cut back with some product to a 3" slump (or is it the other way round?) Ric, did you add superplasticizer? That will increase the slump, allow it to flow more and make the concrete easier to work without affecting the strength if it is dosed correctly. I have seen concrete that had 10X the dose of superplasticizer added and the concrete only hit about 0.5 MPa. The bad concrete was knocked out with hand hammers. Link to comment Share on other sites More sharing options...
Ric Furrer Posted October 31, 2010 Share Posted October 31, 2010 Ric, did you add superplasticizer? That will increase the slump, allow it to flow more and make the concrete easier to work without affecting the strength if it is dosed correctly. I have seen concrete that had 10X the dose of superplasticizer added and the concrete only hit about 0.5 MPa. The bad concrete was knocked out with hand hammers. I believe that was the additive. The local concrete company knew exactly what I was after and delivered two trucks with the load and we had it in the hole in about an hour. I had a box form taking the space of the anvil as on the two piece I needed to sink the anvil into the concrete two foot (about 24" deep and 2x4 foot). The only thing I would really did different is load the box with more weight. I made the box of plywood and reinforced it and secured it to the floor with angle iron and tapcons...when the concrete reached about 5" up the box it began to lift it. I stopped the pour, added a thousand pounds of stuff from the shop into and on top of the box and continued the pour. The displacement of the form was something I had thought about, but not calculated. an aside: I made the drill pattern for the hammer by setting the hammer on a plywood sheet when it was taken off the truck with the crane. I pray painted around the holes and such so I had an outline of the hammer and then had the crane lift again so I could get the plywood out....instant pattern. Ric Link to comment Share on other sites More sharing options...
Sask Mark Posted November 1, 2010 Share Posted November 1, 2010 I believe that was the additive. The local concrete company knew exactly what I was after and delivered two trucks with the load and we had it in the hole in about an hour. I had a box form taking the space of the anvil as on the two piece I needed to sink the anvil into the concrete two foot (about 24" deep and 2x4 foot). The only thing I would really did different is load the box with more weight. I made the box of plywood and reinforced it and secured it to the floor with angle iron and tapcons...when the concrete reached about 5" up the box it began to lift it. I stopped the pour, added a thousand pounds of stuff from the shop into and on top of the box and continued the pour. The displacement of the form was something I had thought about, but not calculated. an aside: I made the drill pattern for the hammer by setting the hammer on a plywood sheet when it was taken off the truck with the crane. I pray painted around the holes and such so I had an outline of the hammer and then had the crane lift again so I could get the plywood out....instant pattern. Ric I get charged $11.50/m3 (about $8.75/yard)of concrete for superplasticizer, so it does not add a lot to the cost of the concrete. I did the exact same thing for the bolt pattern when I mounted my power hammer. Of course, I only set up a 25 pound Little Giant knockoff, so there was no crane involved... Link to comment Share on other sites More sharing options...
Ric Furrer Posted November 2, 2010 Share Posted November 2, 2010 I get charged $11.50/m3 (about $8.75/yard)of concrete for superplasticizer, so it does not add a lot to the cost of the concrete. I did the exact same thing for the bolt pattern when I mounted my power hammer. Of course, I only set up a 25 pound Little Giant knockoff, so there was no crane involved... Cranes are wonderful things..to rent with an operator..I'd not own one if you paid me. My 50 weight mechanical is bolted to a 2" plate (48x48") with the plate on 4x4's so I can get a pallet jack under it to move around. I do not use the tool much, but it works. The plate is heavier than the machine, yet even at 3,300 pounds or so its portable. Ric Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted November 2, 2010 Share Posted November 2, 2010 Yep, the buoyancy of that "boat" was over 3,000 pounds Today's trivia lesson or "who'da thunk it"?: Concrete weighs just about exactly the same as aluminum! Concrete varies a bit due to differing aggregates and mix. Trivia #2: wet concrete weighs the same as hardened concrete! It's a chemical reaction, not "drying". Link to comment Share on other sites More sharing options...
Sask Mark Posted November 2, 2010 Share Posted November 2, 2010 Trivia #2: wet concrete weighs the same as hardened concrete! It's a chemical reaction, not "drying". Good call Grant. This reaction is called hydration. Sometimes concrete is counter intuitive. Adding a little extra water to the mix will sometimes actually increase the hydration rate for a quicker strength development. Link to comment Share on other sites More sharing options...
cwilliams Posted December 5, 2010 Author Share Posted December 5, 2010 Well I finally got the foundation done and poured for my Big Blue. I decided to go the truck route on the concrete, and very glad I did. The pics tell the story far better than I can. Thanks Phil (Forgemaster) for the advice on the pockets for the imbedded nuts. It worked very well and allowed me to not have to pickup the hammer to place on foundation. THis is a very slick setup and I see using it again if I ever have to pour an isolated foundation. Chris Link to comment Share on other sites More sharing options...
KTB Posted December 5, 2010 Share Posted December 5, 2010 I am ready to pour an isolated slab for my tire hammer. The hole is 32 inches X 32 inches X 24 inches deep. I am currently attempting to locate a reliable calculator so I can figure the number of 80 lb bags of mix required. I would love to have it delivered but I think it is only around half a yard of concrete and around here they have a 3 yard minimum. Link to comment Share on other sites More sharing options...
JNewman Posted December 5, 2010 Share Posted December 5, 2010 I am ready to pour an isolated slab for my tire hammer. The hole is 32 inches X 32 inches X 24 inches deep. I am currently attempting to locate a reliable calculator so I can figure the number of 80 lb bags of mix required. I would love to have it delivered but I think it is only around half a yard of concrete and around here they have a 3 yard minimum. I would look around and see if anyone in your area delivers "metered" concrete. These are the trucks that come around with all the components of the concrete in separate bins. All the ingredients are mixed on site. I had 1/2 a meter of concrete delivered for less than I would have spent on renting a mixer and buying portland cement sand and gravel, and WAY less work. Link to comment Share on other sites More sharing options...
Nakedanvil - Grant Sarver Posted December 5, 2010 Share Posted December 5, 2010 Lot of rental yards around here have concrete trailers and they'll mix 1 yard for you and you just take it home and dump it. U-cart they call it. Link to comment Share on other sites More sharing options...
Judson Yaggy Posted December 5, 2010 Share Posted December 5, 2010 Around here some concrete plants have a list of people that will wait for a partial load. For example if a larger job doesn't use a full load sometimes they will haul it back to the plant (if time allows) to pour smaller pre-cast items with. While the driver is returning the dispatcher will call folks along the route that are on the list. You have to be there and ready, but it's a cheap way to get less than the 3 yard minimum. Link to comment Share on other sites More sharing options...
Sask Mark Posted December 5, 2010 Share Posted December 5, 2010 Many suppliers will deliver very small loads, but you will get charge 'small load fees'. You can order 1/2 yard, but you have to pay for 3 yards. Link to comment Share on other sites More sharing options...
KTB Posted December 6, 2010 Share Posted December 6, 2010 Thanks guys, I appreciate the suggestions. I know you can sometimes get them to drop the extra concret they may have on board, it's just not practical for me to be available. And I have a friend with a mixer but I am at his mercy as to when he may or may not be able to bring it by. I am going to look in to the U-Cart thing. I have work accounts with three differnt rental yards. Link to comment Share on other sites More sharing options...
beslagsmed Posted December 20, 2010 Share Posted December 20, 2010 Great thread as I am looking at making a new pad for my machine. I was trying to think how to secure it down, but now have great ideas thanks to the posters of this thread. Link to comment Share on other sites More sharing options...
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