What is the term for the kind of wheel balancing when the wheel still on the car is balanced along with the brake drum? Is there a certain term that is used? I picked up some 45 fin Buick drums and had them put on the 34. Trouble is when I got them the balance weights had been removed. Now that everything is back together and the tires were balanced but because of the weights missing the drums are not balanced. I need to find a tire shop that does that kind of balancing with the wheels on the car.
dynamic wheel balancing? In high school when I first learned how to do it we called it spin balancing...
On the car spin balancing is what it has always been called in shops where we had the equipment to do it. There are usually two types of equipment to do it with. One is the Hunter setup where you clamp an adapter to the rim and put the balancer piece on it and spin the tire up with a motor that spins the front tires or usually by running the rear tires up to speed with the cars's engine with the off side wheel sitting on the floor or stopped with the park brake cable on that side unless it's a posi rear end. the hub that fits the adapter has rings on it that you increase/decrease the weight and move the weight around the rim with. Once things smooth out as close to perfect as you can get you stop and see where and how much weight you need to put on the rim. The other system uses a strobe light with a sensor that usually connects to the rocker panel or frame of the vehicle and the strobe shows you where to put the weight and a meter on the strobe shows the amount of weight. I like that a lot better as you don't worry about marking up a rim, you don't worry about adapters coming loose and in the right hands it is extremely accurate. Dynamic balancing is just another style of balancing the tire and when it was introduced to me it meant how you placed the weights on the rim. The theory at the time was that placing four small weights on the rim (2 front/2Back) and splitting the light point would give a better all around balance to the tire. I've been out of the loop for over 20 years on that end so I don't know what they are doing that they call dynamic balancing these days.
wow... that's old school. Someone was going to give me one of those balancers years ago and I didn't have room... A lot of stock car/Sprint car guys go in for that,, try where they get work done.
if you can jack up the front and you have a pocket full of weights you can do it yourself (only works on front wheels) Should be directions on the interwebz
I think OSHA outlawed those old spin balancers years ago. I thought they were great, but I guess people were getting hit with rocks or debris flying off the tires. Some individuals still have them.
I wonder if a balancing shop that does crankshafts and other mechanical devices can balance the drums for you. Once those are in balance, you could use wheels/tires that are balanced on conventional tire balancers. By the way, I always ask if the tire shop has a Hunter 9700 road force balancer. These machines test how out-of-round a tire is by measuring the slap of a tire on the road (simulated) and give a readout in pounds. They really work and you can make sure you have a smooth tire. I had an Excelsior racing tire on my Plymouth that was sghaking the car bad! it reginstered 64 lbs. road force (zero is perfect)! Coker replaced the tire.
If ya can't get it done right a way,do it your self by; jacking up the front of the car right after running long enough to heat the tires to round,back off your brake shoes/or put the pads out if disk,so the wheel/tire will spin free,the heavy spot will go to the bottom,mark it with a small line and then lift line to 9;00 or 3 ;00,and look at how fast or slow it goes back to the bottom[note that];add balance Wt. to 12;00 from line,try again at 3 or 9,if it moves much slower your close,add just a little more tell it just stays at 3 and 9. And yes a good engine balance shop can do a drum/hub,I did many in my shop before retiring.
Static balancing is balancing in one plane. Dynamic balancing is balancing over the whole length of the part. In your case the best method would be to find a balancing shop that has an arbor that fits your hub/drum assembly and have that balanced by itself. Then put the wheel on and balance the whole thing. They spin to do all this. This is basically the same method someone else was talking about with the pickup put under the axle or A frame near the wheel being done. Those were Stewart Warner balancers. And yes, it is a very good idea to pick ALL the rocks out of the tread before spinning a wheel.
I've balanced thousands of semi tires with a BeeLine strobe unit, it's more art than science but exceptional results can be had if the operator knows their stuff. A semi hub, drum, and dual wheels probably weigh 400-500 lbs and I could usually get them as smooth as glass. Spin balancing on the vehicle is probably the best method because it balances the entire rotating assembly.
Another is someone who still has a "Bear" dynamic balancer,...You mounted the wheel and drum as an assembly, and did a "spin" balance... Those were good for 1/16 ounce tolerances. 4TTRUK
Chuck's Brake and Wheel in Santa Rosa does it. Not sure what they call it, but it's the only way they do it there, with the wheels on the car. They've been in business since '46 and still do a lot of things the old ways.
I thought I would bring this thread back to the top. I took my coupe over to a friends house who is a retired mechanic. He pulled out his old Hunter spin balancer, dusted it off, and put it to use again. He had to fabricate some adapters to use the 15" accessory for my 16" wheels to be able to mount the balancer. What I have on the front is hubs from Wilson Welding, Buick 45 fin drums with no balance weights, 41 Studebaker wheels and Firestone bias ply tires. He was a little rusty because it had been awhile since he had used it. Both of the front wheels had some pretty bad run out, one worse than the other. After a few minutes he was able to adjust the centrifugal weights out to where the vibration was eliminated. It took about 3 oz. of added weights on each wheel to get there, but what a big difference it is now going down the freeway without the vibration. The old Hunter spin balancer he used looked just like the one pictured. Too bad tire shops don't still keep these things on hand.
When GM balanced those Buick drums did they do it with the drum attached to the hub? Or just the drum itself, once we take those drums and put them on 70 year old hubs are those weights in the wrong place? I would think so, but I'm not sure?
Dynamic balancer. Effing brilliant machine. Hoffman was best make here in the UK. Jack up front. Lower one side onto sensor stand. This has a pick-up so when out of round force humps down on it , strope light flashes. Operator is on Hoffman beside tire, which consists of an electrically driven steel wheel rubbing on bottom of tire to rotate at speed, and a light (strobe) which is triggered by the above sensor shining at tire/wheel. Mark any part of tire with a piece of white tape. Spin up wheel/tire. As out of balance thump sets off strobe, at bottom dead centre, strobe light shows up white tape at a certain point round tire, say 3 o clock. Stop machine. Rotate wheel so tape is at 3 o clock and put lead weight at 12 o clock on wheel rim. ie opposite out of balance weight, which is at 6 o clock, setting off strobe. Re start machine and refine. It takes a little practice, but any wheel /tire combo can be balanced easily with one of these. When done, mark wheel and drum with tippex so if wheel is removed, can be put back in the right place. Hard to explain, but we love our Hoffman! Cheers, Tom.
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