Circle Mill Foundation (concrete slab?)

[SPD748]

I purchased and am rebuilding a Frick 0 with 52' track, all steel, 15' carriage, 6-71. Its now time to decide what type of foundation to put all that on. I've read a lot about wood cribbing, concrete piers, etc... My question is, will a solid concrete slab work? If so, I plan on making legs from steel tubing to support the track frame and have the husk rest on steel channel. I was thinking that a level concrete slab would make things easier to setup and maintain. Is there a reason why more mills are not setup this way? Would frost be an issue (I live near Charlotte, North Carolina)? A slab big enough to set my mill on would take about 9 yards to pour, so about $900 (thats pouring 5" thick). I can form, pour and finish the slab myself so labor costs are not a factor. Thoughts? Thanks guys.

-lee

[captain_crunch]

Concrete would be great us poor folks just can't aford it ;D ;D. I would dig Deeper holes where I wanted support posts then pour these holes full of concrete with say like 3" pipe for post and have them stick up 6" higher than needed pour slab over that then cut pipe to the height you want mill frame. Guess I better wake up now cause that was a sweet dream. I got Dirt.pirimid blocks and posts :( :(

[Sawyerfortyish]

Thats how my frick is set up on concrete. My mill is on 8" I beams under the track with 16"I beams crossways under them so its very easy to keep things cleaned up. When I poured my floor where every I beam would be contacting the floor I had dug 18" deeper as a footing and poured it with the floor. My floor is also 5-6" thick except where the I beams are thats 2' there.My reason for making the concrete thicker under support legs was so the constant banging from rolling logs on the carrige wouldn't crack the concrete slab over time. I also put rebar every 2' in both directions and wire mesh on top of the rebar. Also under the concrete is 6" of crushed stone so the frost will not freeze it and I have french drains to take any water away. In 10 years I have never had to readjust my track because of frost heaves or setteling nothing has moved from the time I put it there.

[SPD748]

My mill track is S5 x 10 I-beam. I was planning on installing legs at 36" oc. I think this will properly spread the load on the beams. The bottom of the track frame needs to be 15" above the slab in order to fit the saw pot that I've already constructed. This height will allow for a 60" saw though I currently have a 54". Do you guys think I need more support?

Also, I was planning on setting 15" channel (perpendicular to the track frame) directly on the slab, then attaching the husk and track frame to that channel. The remainder of the track frame will be supported by the tube legs.

Like the previous reply stated, I was planning on adding some washed stone and rebar to the slab. I have the site prepared with well compacted North Carolina clay so soil movement shouldn't be an issue. The pad is about 6" higher than the surrounding grade. I have well defined swells cut on three sides of the pad to handle any water that may attempt to un-do my efforts.

Is there something else I should consider?

[Woodchuck53]

Morning SPD- Good luck with the rebuild. Hard work but well worth the time and energy to do it right up front. I went a different route but yours sounds like good engeneering. Only thing I would consider is if not compacted gravel then at least a good sand base under the concrete. Clay has a high plasisity index and will shrink and expand on you. If on a slope then protect the uphill side with some kind of berm or levy to route any surface water away. Also depending on how wide you go consider sinking a couple of poured in place columns for stability side to side from loaders and other equipment that may be bumping the mill. Good luck and remember we are real visual here so lots of pictures. Also poured in place steel anchors around the edges flush with the slab will allow you to come back and weld post for the roof but want be in the way of setting the track and husk. Stay safe, Chuck

[SPD748]

Thanks for the reply. My plan is to lay 3-4 inches of washed stone under the slab. Do you think sand would work better? All water issues should be covered. I have drainage grade on three sides of the pad. Once finished, there will be positive drainage on all four sides of the pad leading out at least 10'.

[Ron Wenrich]

We put our mills on piers when we first started out.  The mill was sort of an experiment.  But, when we went to expansion, we went with a concrete slab.

Our current mill is an automatic mill set on steel.  The pad is 12" thick and we put 8" I-beams into the concrete wherever we set our uprights for the mill.  That was about every 10'.  We welded the uprights to the embedded I-beams.  We also put our chipper in this way as well as our vibrating tables. 

Your mill is a lighter version.  All you will need is to be able to keep mill support steady, and have enough room to get rid of dirt and sawdust.  My off fall tables are about 6' above the floor.  I have run mills that were simply bolted to the concrete slabs.  As long as your supports are stout enough for the mill that you are running.

[bandmiller2]

Welcome Lee glad you want to do it right sounds like your giving it plenty of support.Three foot spacing is good around the husk and especially the log load and turn area, if your going to use a power log turner be sure to cross brace they pound everything.As you get beyond the off bearers side of the husk your support spaceing can be further apart.Be sure you leave enough space under the mill it fills up fast and you may have to go under it yourself.The old mill clasic is to build the mill on a side hill,logs roll on the carriage ,and plenty of room under.Slabs if done right require alot of expensive concrete which is why their not used more,crushed stone is best under a slab, drainage is king.Pyramid base piers 4' apart and wider than the mill work well,set below frost.Have provisions to shim everything to maintain level as everything settles.Frank C.

[Sawyerfortyish]

Sand will freeze under the slab and may heave the slab but crushed stone will let any water drain out and won't freeze.

[Mooseherder]

My Lane Mill site has been a work in progress for a few years in Northern Maine.  We can only be there a few weeks out of the year so it has become a real slow process not even mentioning difficulty budgeting for it. The area I wanted the site on needed a lot of gravel brought in because of the slope.  That cost me a couple years worth of saving for.  I was able to afford  one truck of concrete along with rebar and associated costs of this slab this past summer.  My brothers and I did the work.  This is the layout I chose for now and I'll add Concrete one truck at a time later on when I retire or semi-retire.  Tying the pads together may have some issues because of frost but I'll deal with it best I can.
If I had bought a Bandmill, I coulda had 4 years worth of sawing experience already. :







I designed a Pit for the sawdust conveyor placement under the Headsaw.
It'll second as an oil change pit if If my dream falls apart. :D

[Banjo picker]

When you get ready to tie on to those slabs, drill into the existing slabs on at least 2' centers about 8 or 10 inches and put rebar in the holes...that will help....They make a speed dowl which is a tube that you fasten to the wall before you pour then you don't have to drill...it does look like some sort of a keyway in one of the pic...that will help some also....But a slab that far north with no footer may be problematic....Tim

[SPD748]

My slab will look similar to Mooseherder's but without the pit. I plan on using a blower to handle the dust. I have enough rebar to grid on 12" centers in both directions. Also like Moose, I'm going to add a vapor barrier. Stone seems to be the way to go so stone it is. My pad will cover about 530 sq ft so 9 yards of concrete to pour 5" thick and 4 yards of stone for around 3" thick. My mill and engine weighs just under 13k lbs. Do you guys think a 5" pad will be enough support or do I need more?

[rpg52]

I mounted mine on sonotubes (12") over footings with lots of rebar.  I had some 12" square plates fabricated, each 1/2" thick, with four 5/8" holes punched in the corners, and mounted four 5/8" L-bolts in them.  As I poured the concrete, I embedded the L-bolts and plates into it.  Later, I welded sections of 3" pipe on top of the plates, which supported 6" channel iron.  After it was all assembled, I adjusted the height of each pipe support and fine tuned the level of the track on top of the channel iron.  Worked for me, but there is lots of ways to skin this particular cat.
Ray

[sigidi]

Looks/sounds like it will be a pretty neat saw shed 8)

keep us up to date with some pics ;D

[Woodchuck53]

Evening SPD-- Yep the stone is much better. Drainage sounds good being on a slope. We here in the south like my place is wet. Can't get off the right a ways right now and can't drive a 16d. nail in it during the summer. I'm so flat I had to install a sump pump behind the husk frame to handle the seepage. You want have that problem.                                       The foundation looks like it will do all you will need. Looks real good.
As you can tell by now there is a wealth of know how here all you have to do is ask. Keep it coming.

[bandmiller2]

No need to get too carried away with extensive foundations unless your building a full blown commercial mill. Sections of utility or better yet highline poles set solidly in the ground are good for close to 40 years.Make a plan where you want to set the posts.Dig a good hole usally 4 or5' is enough,dump a wheelbarrel load of cement in each hole tamp and level.Cut a flat clean end on the piece of pole slap some creasoat of whatever you have on the end.Set the pole on the hardened cement,a couple of shovelfulls of crushed stone for drainage then anouther wheelbarrel of cement level and backfill.Use a laser level or line and cut the tops level.Frank C.

[Two-Lady-Sawyers]

What about using rialroad ties instead of the utility poles for the foundation. We will be setting up our Belsaw in about three weeks. That is when the ties will be ready for me to pick up if you guys think they would do the job. They are like new. Real good price. Thinking about setting them like piles in the ground on concrete pads backfilled with crushed granite.

Jillian

[Ron Wenrich]

As long as it doesn't move, you can use practically anything as a foundation.  If they're used, watch out for rot. 

[bandmiller2]

Jillian,are you planning to dig holes and plant the ties like trees or lay them flat on the ground.I've seen Belsaws just set on blocks that seemed to cut well fella just checked the level every so often.Really a good tie is the same as a utility pole.Frank C.

[Two-Lady-Sawyers]

Frank, we are going to plant them like trees, 6ft deep. We are setting the saw up with 50' of track and want a nice stable base. Can't wait, I am ready to make some dust. The ties I have coming are only about 7-10 years old. They look almost new.
Jillian

[bandmiller2]

Jillian that will do it.What I did on the two mills I've set up is dig the holes then pour one wheelbarrel [big contractor size] of concrete let it harden.Set the ties/poles on it a couple of shovelfulls of crushed stone for drainage then anouther load of cement, level refill, and tamp.If you have the hight cross brace just like bedrock and good for 40 years at least.Frank C.