Balancing out the Bounce---

[hotater]

I just replied to Quinn's post on 'cooling the Listeroid' and then notice 'the balancing Guru' from NC has just joined us, so decided to start a new thread for a common Listeroid quirk.....

Quinn---

Great post, THANKS!!   You're right about the width of the cart.  My mounting space wouldn't allow a wide bed...in fact it's so close to the wall now it's just terrible to work on.   To tell the truth, it's scary to think of things wrapped around the flywheel spokes in such tight quarters, too!!

Mine rocks fore and aft....the whole cart wants to slide to the front and back about half an inch.  I built the cart with heavy, but short casters and mounted the engine thinking I could roll it from it's 'running' place to it's 'fixing' place by unbolting it and wheeling it around.  NO way!  

   First I set four half inch lag shields in the shop floor and ran a chain over the cart and put a binder on it to hold it down front and back...that lasted less than a minute.  I then cut angle iron to run across the cart and put turnbuckles to new lag shields and better bolts so the tension would be straight down. ..... Ten minutes...

   I was out of half inch lags shield and it was fifty miles of four tire chains and ice to town, but I finally found a double handfull of high grade 3/8 studs and steel slip expanders in a hammer drill case I didn't know I owned.  New drills too!
      I cut two pieces of  steel bar scrap and bolted them parralel to the cart to the floor with four 3/8" heat-treated studs on each side then welded sections of 3/8 chain to the steel bar.  I held it down with six turnbuckles pulling lenghts of chain across the cart.
    One by one the chain links pulled loose or broke.
    I re-welded the chain links but bolted them first to a better pieces of scrap iron held again with four 3/8" concrete anchors on each side.
  My buddy, Les from Colorado was up here that week and I kept him busy drilling more holes and setting more lags to be SURE it stayed around.   It wasn't going anywhere this time!....

....but it did.

But that time we were watching for nearly an hour trying to see what was loosening first.
   The cotton-pickin'  casters would gradually rotate around as the engine ran,  and the slack from that would propogate into what became a gradually strenthening pile driver that pulled the shields, broke chain, and even pulled a turn-buckle in two.
  SO, I put timbers front and rear to suspend the cart by the ends and take the casters out of play.  Of course my 'cock of head and say, 'this'll be neat'' cart design was such that the props on the ends didn't support it correctly and I had to run a chain around the whole works and winch it together with a come-a-long to make it FINALLY stable.   I ran it that way for two weeks with an occasional weld failure or broken stud.
   It's now mounted flat to the concrete with brackets bolted to the cart and 3/4" anchors I bought military surplus.  They're 12 inches long and use carbide blocks in a wedge arrangement that just don't allow any slack!  THEY are solid.

The Lister/pumphouse building is an 'L' shape with the little portion about six by eight feet and the Lister is mounted dead center of that 'wing'.  The well curb and piping is in the longer, bigger side of the 'L'.  It's a 'built on grade' slab with no footers and  the little side wing has nothing but 1/4 washed gravel under it.  The Lister broke off it's portion of the slab within days and now that end of the building seems to be 'alive'.       At least it seems happy now.

I'm betting it's the flywheels that are WAY out of balance.  They look like they were cast in somebody's Bar B Que pit.  

HERE'S why this forum is so good---  I *thought* mine wasn't too bad until I started reading about people cranking them on the crate bottom!!  I do believe if I'd cranked mine like that it would have chased me out the door and gradually shredded  everything in sight and stomped the residue into mud.

The very *thought* of mounting my engine on rubber tires brings visions of summersaulting Listeroids on a trampoline.    

[Reno Speedster]

Yikes!  It makes me glad that I'm pouring a thick slab for my engine house! 

Morgan

[quinnf]

Jack,

You know, stone quarries use something similar to those slip expanders to crack granite into manageable hunks, and as you wrote in the story on Utterpower, the concrete in some of the slabs might be a tad thin, and who knows how it was cured. 

None of the common fasteners holds very well in tension, especially on a live load, but they are pretty good in shear.  I found one day (to my delight) that a diamond blade in a skillsaw does wonderful things to old hard concrete.  Why don’t you saw  four undercut holes, then break out the plug, dig down a little, undercut the slab and sink four J-bolts in hydraulic cement (expands upon curing).  Dumb question:  because it’s a pain to do that, and it’s hard enough to work on the ground, let alone below grade.

You’re probably right about the flywheels.  I’ve been toying with building a bubble balancer for the flywheels.  A piece of aluminum round stock machined into a top-hat section with a tapered hole bored most of the way through from the big end.  Set the top hat in the 2” hole in the center of the flywheel, heft it on top of a pointed piece of 3/8” steel rod clamped tightly in a vise, place a bubble level top dead center, and determine how much weight you need to to level the thing.  Do that with each flywheel and compare.  Then check that against the weight of the big end of the rod with the little end supported off the scale. 

Another thing that I’ve been thinking of is SurplusCenter.com has some 31.5” pulleys that look like they might be used on an elevator or something.  They’re part no. 1-2338 and weigh 280 lbs each and cost only 40 bucks + shipping.  But of special interest is the bore is 1.97” which is, coincidentally, the diameter of the bore of the flywheels on a 6/1 'roid.  The keyway might even be right  (See where I’m going with this?).     My only concern would be the roller bearings.  Dunno if they could handle that much weight.  Then again, look at the sillly little TRBs they have in the hubs of a massive old Caddilac! 

Seems like it might be easier to determine the proper counterbalance weight starting from a homogeneous, machined pulley/flywheel like this than to try to make a cruddy Indian casting balance.  Ir would definitely be more fun.  You could cast a lead counter weight and bolt it to the new flywheel.  And when you’re done you’d have 500 or so lbs. of flywheel mass!  When I broached the subject to George, he said that much mass might not be a good thing.  Still, the Lister Start-O-Matic light plants had flywheels around 600 lbs total, so I don’t know that would be excessive.  Imagine cranking that over on a cold morning, though!

Here’s the particulars on that pulley.  I see it’s getting late.  All this talk about cast iron, broken concrete, huge flywheels and things that go thud in the night has me pretty wired.  Gotta hit the rack.

G’night.

Quinn
   
31-7/16" CAST IRON PULLEY
New, cast iron pulley. Machined outer circumference.

SPECIFICATIONS

    * Bore: 50 mm (1.97"), keyed
    * Keyway: 14 mm wide x 4 mm deep
    * Outside diameter: 31-7/16"
    * Hub width: 7-1/4"
    * Belt groove: 52 mm wide x 55 mm deep
    * Outer edge of pulley width: 5-3/4"
    * Width of 2 flats to the outside of belt groove: 2-9/16" and 15/16"
    * Shpg. 280 lb.

[kpgv]

Hi All,

I have some thoughts on the ballance issue.
I don't own a Lister (yet).
Feel free to hoist the BS flag at any time.....

Lister singles are externally ballanced engines.
There is no way to ballance one without counterweights on the flywheel(s).

Drilling holes in the rim of a cast iron flywheel is a good way to cause a BURST FAILTURE!
Another good way is overspeed.

As designed, the counterweights are installed OPPOSITE of the crank pin.
They are sized and placed to counter the weight of the crank pin AND the weight of the big end of the rod, bearing, and fasterers.
My suspicion is that the ballance problems many of you have is caused by the CENTER hole being mis-located in the CASTING.
(It is also possible that the gib-key slot is mis-located with respect to the counterweight/ crank pin relationship.)
If the center hole is mis-located, and it is the first machining operation done on the raw casting, then all of the following machining operations will ALSO be mis-located. For example:

The center hole is bored .125" off center TWARD  the counterweight.
A rough calculation on my part gives a weight of ~1.5 POUNDS extra on the rim OPPOSITE of the counter weight.
I'm guessong this will reduce the effectivness of the counterweight.
You probably won't notice anything is wrong by looking because all of the following machine operations are equally mis-located (concentric).
The flywheel will visually look fine, BUT the WEIGHT is mis-aligned.

When your Lister is running at 600rpm, the surface speed of the flywheel is ~43MPH, or ~63fps.
How much will your pickup shake at 43MPH with tires out of ballance by a POUND or so.

Please, someone that has one of these that runs rough, measure the THICKNESS of the RIM of your flywheels.
Measure inside and outside, at each spoke and between each spoke, both flywheels.
A center mis-alignment problem will show up as a thickness inconsistency of the rim.
 

Most of the technical info I am using comes from a book called "Machinery's Handbook", 22nd Edition.
There is a section on flywheels starting on P.223.
Get this book and READ this section, and DO the math BEFORE you start modifying your flywheels.
George B. is right on the money about the danger of having a burst failture of one of these.


I hope this is useful...

Kevin





   

[quinnf]

Hi Kevin,

No BS flags are going to fly.   I'm sure we all appreciate your input.  Especially since we agree with you.      The flywheel I was talking about bolting a lead counterweight to is solid, no spokes and is made from much better stuff than are our Listeroid flywheels.  Once a trim weight is determined for, for example Jack's spoked flywheels, the weight can be cast and then clamped to the rim or clam-shelled around a spoke to avoid drilling holes. 

The 'roid flywheel castings are so rough what you say might be the case.  It looks like the casting is first bored, then the outside of the rim is turned.  The sides of the rim are trued, and the inside of the rim also shows some machining marks, but they didn't bother to ensure all the voids were machined away.  Just filled with plaster and painted over. 

While running, the outer surface of my rim is absolutely dead-nuts true (I'm told that's a technical term).  But the hub and spokes are so rough it's difficult to tell if the casting was bored on center as you explain.  I've been looking for a strobe that I use to see if I can locate an anomaly in the casting thickness, but I haven't found anything yet.

A great big gear-driven lathe would be nice to have access to . . .   

On the other hand, these engines, being vertical and mounted on a 13" square are never going to be smooth, if only due to torque effects.  But in a case like Jack's, where he's really got a rough one maybe there's a way to keep it from cracking concrete.

Quinn

[hotater]

Kevin--

Good post!  Welcome to the Lister shed.

My flywheels are turned on these surfaces--- Outside diameter,  inside diameter of the rim, both sides. Both faces of the rim, both hub faces and hub OD.
  I think the problem is inconsistancies in the castings.  I have a couple pics on george's site of spokes short 10% of their design volume.  My Listeroid has an intergral counterweight AND spokes of varying weights scattered around both wheels.  Compared with the 'elegant' castings of the original Lister posted in the albums, I'd say the foundary that did mine wasn't qualified to cast man-hole covers....flywheels!!??  (I once had a ten inch cast iron hydaulic piston come apart in the lathe...it got crowded in a hurry.
  I thought of the misplaced key, but mine is close enough to eyeball and call right.  The shame there is that if it's wrong it's a matter of strapping weights around different places to fix it.  It can't be re-machined, (practically speaking, there ARE ways)

You are very right about drilling and milling on spinning cast iron, especially ones cast of Indian 'sponge grade' remelted fence wire and re-bar.  That coat of goober green paint covers up  a LOT of stuff.  I stripped the old paint and filler beneath and made 'new' spokes out of Bondo and then re-painted.  The GOOD news is that by using a needle scaler to clean the old green gunk you realize the flywheels are not cracked.  They ring like a chime!

Everybody keep their eyes open for an old tire balancer used in the sixties that had a means to rotate the tire (we don't need that!), and a magnetic vibration sensor...it was adjustable to weed out the higher freqs.....hooked to  a strobe light and stuck to a cross-arm or fender.
    In use,  a chalk mark was put crossways the tire and  the tire run up to 60mph or so.  The heavy part of the tire fired the strobe at bottom dead center and showed the operator where that spot was in relation to his chalk mark.  It was a quick and easy way to balance front tires without removal.
  It would be perfect for balancing engines!!  The amount of weight would be trial and error, but the location of it would be perfect.

I have my old Machinery Handbook *somewhere*.  I remember packing it.  Seventeenth Edition and every page stained with cutting oil and the occasional blood spot or bug.   I can turn to the 'threads' pages by looking for the darker stains in that section.  GREAT RESOURCE!!

Quinn--  'Dead nut perfect' is a recognized and valid technical description of tolorences in all machinist and welding trades....and golf.   

[cujet]

Ya know, we balance all sorts of things here at work with the old fashoned method. "the try it and see method". I say you should try adding weights in incremental amounts. Try both positions, in line with the crank throw and 180 degrees out.

I am sure you can find some lead weights that you can affix in a temporary and safe manner. I would suggest stick on wheel weights, placed on the inside diameter of the flywheel, apply similar to automobile wheels.

Chris

[kelarsen]

If you disconnected the conncting rods going to the piston, would not gravity win out and you could see the heavey spot?  because
it would be at the bottom.  I am only thinking of buying one and can honestly say I might be full of s**t.  What  say the experts?

Kevin

[rocket]

i think that might be true if you eliminated most of the resistance... my concern is that most lister fly wheels are weighted with a counter weight to balance the forces of the engine (the fly wheels arent symetrical on purpose) .. pistons and all... i have scratched my head about how to balance the engine and fly wheels and have no good solution. the methods on georges cd while having worked for people.. the logic seems to elude me.

[hotater]

Welcome, ya'll--
kelarsen---    For the gravity method to work you have to weigh the big end of the rod and put that much weight on the crank pin to counterbalance the the counterbalance.  THEN you can find the heavy spot by gravity by loosening the thrust plates on the crank bearings a little to free it up to it's maximum.

Trial and error works but in this case the weights involved are more in pounds than 1/8 ounce increments.  When you consider the quality of some of the castings and then think of the centrifical force involved and the acceleration of parts that don't stick, (I think my one ounce magnet is somewhere over the next ridge)  AND the fact that you have to reach over that flywheel to shut it down and your arm is not near long enough to keep your head out of the way!....  Adding weights becomes more of a *theoretical* exercise for me.   

I  do have a 2.6 hp Mini-Petter running with nearly a pound of magnets stuck in the (DEEP) flywheel recess.  It makes a difference in smoothness, no doubt.
   I used two ounce round magnets and stuck one in the flywheel and marked the position, then cranked and ran the engine a few minutes.  At shutdown I saw the magnet had rolled about 40 degrees inside the flywheel, so I stuck another on at the original spot.  It migrated too, and the third and the forth and fifth.  The sixth two ounce magnet stayed about an inch away from the other cluster and number seven stayed at the original spot, or anywhere you stuck it.  That told me it was about as good as it was going to get in two ounce increments.

THe REAL secret to a very smooth running engines is to bolt it to somethng VERY heavy and solid.  When the Lister manual says the proper foundation starts with a cubic YARD of concrete and 18" mounting bolts you can bet they knew what they were talking about.  Everything else is just compensating for the lack of foundation.

[hotater]

Amen

[kpgv]

Hi All...

Re balancing,
I was thinking of when I worked at a machine shop that made fire hydrants.
We went over all of the cast iron castings and filled the voids with "Devcon" plastic steel (the liquid kind).
(Voids in sand cast iron isn't just an "India" thing).
It stuck PERMANENTLY!
Anyway, I wondered if making a "slury" of fine lead shot (#9?), and Devcon might be effective, and safe to apply to the inside of the flywheel rim as balance weight...
Of course, the iron will be paint free and clean...
A smooth coat could be applied over the "shot" layer to smooth it out.
It's also machinable.

What say you.

Kevin

[quinnf]

That level of cluelessness boggles the mind . . .

Oops!  Not you, Kevin, the other guy . . .

[quinnf]

I've been thinking about balance; something most gearheads are sometimes told they need more of. 

I wonder how smooth the 12/2 runs.  With the 180 degree crank the inertia of the pistons and rods balance out, so no counterbalance is needed on the flywheels.  Just like the half dozen Honda 350s I had so many moons ago.  But a 4-stroke engine with a 180 crank means that the cylinders fire half a rev apart, then coas through 1 1/2 more turns before they fire again half a turn apart.  Sort of like a hit 'n miss engine on caffeine.  Love that "Ta-Da" (pause) "Ta-Da"  lope on startup.  But I wonder how smooth the engine runs with those torque pulses firing at such irregular intervals.  Comments anybody?  Rocketboy? 

Quinn

[cujet]

I can only assume you are refering to me as clueless. I am quite sure you are correct That is why i am not a millionaire.

However I do balance critical things at work. I work for a wealthy guy as Director of Maintenance on his 8 aircraft. A Gulfstream 550, 2 Eurocopter EC135's, A PC-12, 2 Extra 300L's and 2 high performance motorized gliders. I balance all the engines, props and rotors. I use an ACES 20-20 with an optical tracker, various accelerometers and both magnetic and optical pickups. FWIW, I do have a good handle on balancing engines, including single cylinder 2 and 4 stroke dirt bikes, (often the most difficult of all).

While the ACES is great for balancing nearly anything, balancing can be done manually. Sometimes a welding rod with a small flag on it, taped to a rigid surface will show vibration quite nicely. George has a fine writeup on balancing on his Listeroid CD.


Chris