How Big a foundation for a 6/1 SOM

[TxBlacksmith]

Trying to multi-task, I am planning to start the foundation for the 6/1 SOM I just aquired.
I have the original cast base for it, ( it seems to weigh 200-300 lbs), and I assume the engine, being an original
will run fairly well balanced.  With the heavy fly wheels etc, this setup is going to be very heavy, so I am curious
as to how big/deep of a concrete pad to pour for this.  Several posts for the Listeroids, have mentioned what seems to be
massive pads for the engines, to absorb vibrations etc? 
I was planing 12-18 inches deep, and a layer of rubber horse pad underneath the cast base. 
Am I on the right track here?

[George A]

If I recall, the original Lister manual dictated a base using a full yard of concrete, or around 3000 lbs. (it might be different with a SOM due to the extra weight of the cast iron base). As for the rubber horse pad, that's one of those ideas that sounds great at first, but could lead to disaster later. You don't want any "give" so as to protect the cast iron from excessive vibration or "working" which would break off mounting ears eventually. In other words, you want it solidly mounted. The usual method is to make the pad separate from your floor, so as to not conduct vibration to the rest of the building.

Again, going from memory, the engine is set on the dried pad with steel or stone wedges at each corner for leveling. This leaves a space between the engine and pad, so a small "dam" of wood is built around the engine base which is then filled with a rich slurry of cement and fine sand. The slurry fills the void, self levels and when dry the engine mounting bolts can be tightened (the wedges are left in place). This was a common method of securing heavy machines so that there was no rocking or vibration when running.

[mike90045]

I drilled and epoxied anchor bolts into concrete for my steel ladder frame.  Between the steel and concrete, I used 1/4" thick wood flooring planks to absorb some of the vibration, but not let things rattle.  The slab is 12" thick, 8'x12' on top of 2' of packed gravel.  The ground 6' away still carrys vibration.

[TxBlacksmith]

Would someone explain this to me?  Found it in an old post on here...

Don't forget the grout....

always grount a machine base in place never directly to the block as poured.
 

[Hugh Conway]

Tx;
Grouting ensures a  flat plane to bolt your engine to. Otherwise, uneven bolting stress can break casting.
BTW my Start-O has a has a heavy base too, though it is welded up steel, not cast. Has original Lister data plate riveted on. Apparently several different SOM bases.
Search the forum for "grouting". Lots of info there.  I use "Rockite"
Cheers,
Hugh

[listeroil]

This is from a Lister manual and give dimensions of the foundations.



Mick

[TxBlacksmith]

Thank you for the help Gents.  A recent wrench (spanner?) in the works may not allow me to permanently mount it where
I had planned.  So now I am wondering about mounting it to say 4-6 railroad ties well bolted together and "fixed" in place?
The soil is very sandy, so vibration to the cabin will not be a problem.  It seems that a lot of the old pics of SOM's used
in England were often sitting on the floor in the barn?  Of course I would not consider this, but it seems
strange given their origin, and the fact that many were planned for years of use in those locations?

[dieselgman]

The SOM sets were mainly supplied on heavy cast iron pans (with substantial mass of their own)... and the original sets were likely balanced to a high degree such that they were not bouncing or sliding the skid around too much.
A few issues to consider with a wood foundation: wood will slowly absorb a large amount of oil and/or fuel if it is frequently exposed to it... potential fire hazard. Wood will also flex and wear quite a bit under vibration against iron, your fastener system will need to be thru-bolts or something similar to allow for routine tightening up.

dieselgman

[BruceM]

I've used a wood base for my 6/1 with no troubles for the last 7 or so years.  It was sealed with urethane (oil base) paint.  It was supposed to be temporary just for testing but nearly 3000 engine hrs later it still looks pretty much the same.  I do try to keep it cleaned up, the 8hr oiling service includes wiping up any oil on the base.  I've copied it for the propane conversion project.  I used 1/2x6" lags, and have not had to tighten them since the first few hundred hours.  I did spend an entire afternoon balancing it via the Mr X method, though now I'm a fan of 38ac's method as a time saver.

I do admire the nice steel bases I've seen here, and sure wouldn't turn one down.  I have a woodshop so I tend to use wood and my time whenever I can as my budget is tight.

[AdeV]

My 6/1 S-o-M, with the heavy flywheels & cast base, sits on 2 short lengths of 2"x2"; as the floor's not totally level, I have another piece of wood wedged between the wall & the cast base to stop the machine walking forwards into said wall. Obviously engine & generator are bolted to the base, but the base is not tied in any way to the wood it sits on, nor is the wood fastened to the floor. I can cheerfully run the engine for hours with a 2kW load, and it doesn't go anywhere, nor is there any noticeable vibration. YMMV of course... but if it's an original Dursley Lister on a cast base, you should be fine just parking it on loose dirt. It might be an idea to stake it down so it doesn't wander away by itself, but I doubt you'll have "thump" problems, or any nasties like that.

[TxBlacksmith]

Well, its beginning to look as though I am going to have to mount my SOM on a 5X10 trailer, at least temporarily due to legal problems with the land my cabin is located on.
So I have a couple of questions...  I am considering a couple of really clean railroad ties, bolted together, to then mount my SOM on its thick cast base.  and then bolting? this down in the center of this trailer.
I would however like to construct a "skid"  type of setup, so if needs be, I could lift the whole mess out of the trailer as is, without having to disassemble things.  If and when I get a mostly permanent place for the 6/1 to reside.
 
Also, do I need some type of support to shim under those heavy flywheels while moving the trailer from place to place....don't want a bend in the crank 
I have seen some similar setups on the trailer rigs that some of the guys haul to the hit/miss engine shows...   necessary? or just overprotective? 

[BruceM]

I think planning for shims/blocking under the flywheels is a good idea.  My neighbor's Lister clone had a very slightly bent crankshaft, equal and in the same direction on each side.  We strongly suspected the pallet was dropped in freight.  It was correctable with some effort but still makes me think that the old iron guys with blocking under the flywheels were not being overprotective.  A pothole that bottomed out the trailer springs, for example...