MC Hammer

Shop Build Foundation Question

Recommended Posts

So I've begun the process of building my foundation for my shop addition.  I spoke to our local code guy and he approved my plan for the 20 x 12 monolithic slab design.  My question is that I'm trying to think ahead with this design.  I'm building a coal forge table to set my gas forge on that will easily be ready to accept a metal pan & fire pot someday if I decide to try coal.  The other thing I wanted to do was build one corner deeper & stronger in case I get a power hammer someday.  The slab will be 4 inches in the middle and 12 inches on the monolithic sides.  My thinking was to go thick in that corner with extra rebar.  I could really use some guidance.  

Share this post


Link to post
Share on other sites

I can't offer any suggestions other than to keep the hammer separate..   This of course depends on what kind or type of hammer.. 

My new shop will be going up in the next few months and won't be putting a floor into the shop for at least a year or even 2..  It will have a full footing and frost wall and once I get everything arranged the power hammer (200lbs Fairbanks) will be moved into position and a proper footing will be installed... I'll run it that way for awhile then pour the floor.. 

40X60 is the shop size steel building.. 

Share this post


Link to post
Share on other sites

Keep your power hammer inertia block isolated from your structural concrete unless you plan on running a hammer of 50# or less and don't have close neighbors.  

Share this post


Link to post
Share on other sites

Isolate any parts that have percussion or vibrations from your slab. What type of soils are you dealing with? Do you know the soil bearing capacity and frost line?

Share this post


Link to post
Share on other sites
19 hours ago, Judson Yaggy said:

Keep your power hammer inertia block isolated from your structural concrete 

this is the way to go!  it does of course make it tricky with the planning when you don't know what you are likely to get. there is a smidgen of a difference between a 400 and a 100# 's requirements.

Share this post


Link to post
Share on other sites

Whether or not you use an isolated hammer foundation depends on the hammer. Bob Bergman's Nazel 3B and his 300 lb mechanical helve sit on the shop's 4" slab floor. My shop has a 6" floor with a section approx 6' x 8' along one wall that's 8" thick and double rebar on two levels. I took special care to prepare the grade and compacted it by slamming it with the back hoe bucket till it bounced then laid the next lift. Lather, rinse, repeat. I'm not a fan of having equipment in corners, what will you do if you want to forge the center of a 20' bar? 

On the other hand, isolating the hammer foundation whether you need to or not won't hurt anything. Not a THING. Outside of a little extra hassle it's a can't hurt might help.

Frosty The Lucky.

Share this post


Link to post
Share on other sites

My recomendation is for best practice, smaller hammers need not apply.  I ran a 25# LG for 7 years on a 4" slab not even bolted down, it was good enough.  Would I do the same today knowing what I know now?  No.  A friend has a 3b set up same as Bob B's, it's totally destroyed his slab.  

Frosty's thickend slab is a good compromise for hammers of a certain size.  

Share this post


Link to post
Share on other sites

  Isolate your hammer foundation block from the rest of the floor and bolt it down with a timber or mat cushion . The people that originally designed and built these hammers always included a plan for a proper foundation  in the factory literature to ge the best performance and longevity out of the machine.  

If you really just can't figure out where the hammer is going to go , you can always rent a concrete saw or hire it done  to cut a hole in the existing slab when the time comes.

Even if you don't have a hammer , they are all pretty similar in general layout and you can mock one up with a plywood template and figure out the best location to approach the dies from both the front and across the length of the dies. 10' or 12' is about the maximum length of hot steel that a person working unassisted can manhandle out of the forge and get under the hammer.

 

 

Share this post


Link to post
Share on other sites

Thanks everyone for all the good advice.  I have great draining gravel in my next of the woods - gravel pits all around me.  I hadn't thought about the corner being a pain in the rear as far as running long stock through the power hammer.  I think that I'll just have to plan on cutting the slab some day if I get a power hammer.  It's just too early for me to know where I'll want it some day.  

I guess I see it like the guy who wants to drop his anvil post in the ground before the concrete pour.  What if he finds he doesn't like where the post is?  I think I'll regret trying to figure out where the power hammer is to be located before I have seasoned as a blacksmith.  I may never need one or I may really need one.  I think the future blacksmith is yelling at me telling me not to box him in with a location now.  Thanks everyone for giving me good advice.  It's possible to plan and do this now, but I don't think it's the wisest choice.  

Share this post


Link to post
Share on other sites

Good move, rushing tends to make mistakes permanent more quickly. If you don't have anything special in the slab it's nothing to saw out an area. I put infloor hydronic heat tubing in mine so I didn't have a choice if I wanted a hammer slab. It still isn't isolated but it's tough.

Frosty The Lucky.

Share this post


Link to post
Share on other sites

Looks like August is the month that my shop foundation will be going in.  I decided to rent a mini excavator to make shorter work of digging out the foundation for my monolithic slab.  I live in gravel country so there are 45.5 stones per square foot of soil, yeah hand digging anything is a pain.  

Share this post


Link to post
Share on other sites

MC Hammer.. That is great..  Congrats.. 

 

Starting next week I'll be taking out 10 trees to make way for the new shop also..  Sadly we don't have a gravel problem but a water problem.. 

 

Share this post


Link to post
Share on other sites

The NEB website has some power hammer plans, including foundation drawings, which will give you an idea of the scale you'll be working on.  Also, Torbjorn Ahman has a great series on youtube of digging and building a foundation for a self contained power hammer.  I think it'd be worth a few minutes to watch, so again, you can get a sense of scale, and also see some details, like the foundation isolation and foundation bolt preparation.  Since you don't have a particular hammer in mind, it's not possible to plan ahead like TA for the bolt pattern, but don't worry.  Epoxy anchors are incredibly strong, and routinely used in industry to hold down massive dynamic machines.

Share this post


Link to post
Share on other sites

JLP - I'm super ready for a dedicated space after wheeling everything in and out of the garage.  I think I'd forge more if I could slide out, fire up the forge, and go at it for a couple of hours.  Now it's quite a production to wheel everything out, but still worth it.  I know my shop is not nearly big enough at 20 x 14, but I'm out of room with a septic and a sewer line that I can't get near nor run an excavator near.  One space saving idea I have is to incorporate PVC pipes into the wall that extend under my existing flintknapping shop that is a single wide trailer.  The pipes can store long stock and can be fitted with a removable cap.  Short pipes mounted through the wall under the long pipes will hold the same stock's smaller pieces.

Hiker - I'm going with the idea of pouring my foundation and then someday several years from now if I get a power hammer I'll cut the foundation and do the proper thickness and structure to accommodate it.  I may never get a power hammer.  Plenty of good blacksmiths out there that don't have them.  We'll see.

Share this post


Link to post
Share on other sites

20' long is enough room to put your stock in the rafters so you won't have to bend over to get or put a stick. 

20' x 14' is a nice space if you're careful about layout. Don't do any built ins till you've played in the space a while.

Outlets and lights, there are never enough, several runs. Windows and vents. You don't need a lot of doors though a large one to get work and stock through and a man door is good.

Of course that's just my opinion. 

Frosty The Lucky.

Share this post


Link to post
Share on other sites

20X14 is a great size..   The trailer is 8X10 and for singular work or a sledging guy it offers ample room for general forge work up to about 4ft long..

It really becomes how or what you have a desire to make..   When  I started getting into Wrought iron work  the old shop at 25X40 wasn't big enough as there were pillars at the 25'mark on the 40ft run..  I had a few scrolls that were 35' long and it become a matter of bending both legs and then forge welding in the middle..  

Frosty called it on it all.. 

The only thing I find is so consistent is the distance and the way the forge, anvil, vise, water tub are laid out..   While i do ok working at others places there is a work flow that just makes sense to me.. 

Finding this for your own space can mean a big difference.. 

Share this post


Link to post
Share on other sites

I've done an awful lot of small work in a 10'x10' area.

Share this post


Link to post
Share on other sites

It is pretty amazing the quality of work that comes out of small spaces..  I knew 2 very good smiths that shared an 8X8' chicken coop  for a few years.. they had both a straight shot through the door to the anvil and had a vise mounted outside for hacksaw use.. 

I still see one of the guys a few times a year and he always say's what a great time that coop shop was.. 

Share this post


Link to post
Share on other sites

My shop for 30 years was 16'x20'

 I have a 5'x10' table, 25#lil giant,25# treadle,commercial sized post drill, Camelback drill, 255#anvil, 8"post vice, champion blower and large forge, cone mandrel and swedge block and many stands.

I had plenty of room for all my hand tools, fasteners, etc.

Cozy but nice. Never had a problem with anything i made from gates and railings to crafts fair products. 

My forge was in a corner with a pass thru in the wall to allow me to work 20' lengths.

Lol, taught classes, demo'd for our schools, boy and girl scouts spent weekends camping and smithing., and even hosted a state conference once upon a time.

12'X12' is as small as ive had, and for me, that's as small as I hope to ever go for full time smithing.

Share this post


Link to post
Share on other sites

I think the key to a small space really is an efficient set-up.  Everything needs to flow.  My wife and I measured my triangle of work space outside when I haul everything out to forge and 20 x 14 will seem like a dream.  I like my forge, anvil and post vise all withing a few steps.  The layout I have currently will call for one side having a continuous work bench running down it with natural light coming in the window and shop lights above it.  I'm going to be careful with the lighting as I want it dark enough so I can see the steel's heating color.  Working outside currently, it's tough to tell cherry red from black iron on a sunny day let alone other colors.  What I plan to do is have different lights I can turn on and off as dedicated switches.  I'm leaving room at the end of the work bench for my grinding station when I get a belt grinder suitable for metal work.  My anvil and post vise are going to remain movable.  Once I work for a while I'll find where I want my post vise as far as the best working place for it and mount it permanently there.  My smaller post vise will find a home on my workbench for detailed file work.  I'm going to keep most things movable until I nail down how I work best.  The work bench will be built later after I'm sure I really want it going down one side of the space.  This will leave me with a free corner.  I'll just be thrilled to have a forging place indoors.  After I'm sweaty and tired from forging, it's a kick in the rear to have to move everything back into the garage and my woodshop.  I was amazed today when I walked into my woodshop with all my forging stuff outside.  I actually have room in there to work!

Share this post


Link to post
Share on other sites

Back in the day of outdoor demo's on the ground I used to carry with me a short section of stove pipe that was capped off on one end and it had a rag on the other.. The rag I would soak with a little water to keep it damp and when I needed to see the color of the metal I'd thrust it into the pipe which I kept on the side of the forge.. 

Share this post


Link to post
Share on other sites

Back in the days of crossing the treeless  US Prairies by ox drawn wagon  they mention using a suspended empty barrel to provide a dark area to judge colour in.

Share this post


Link to post
Share on other sites

jlp & TP - that's a great idea.  Boy, why didn't I think of that<_<  

Share this post


Link to post
Share on other sites

I would suggest a nail keg as being more portable; they of course had water barrels on the wagons handy...

Share this post


Link to post
Share on other sites

I had a nail keg too..  I prefer something that is metal vs wood.. Nail kegs are also fairly weak when not loaded..   I had to add extra screws to keep it together.. 

I still have a nail keg that was given to me..   Every time I practice  with making nails as a warm up, I throw a few more in the keg.. After 30+ years I only have the bottom covered a few inches.. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now