Very accurate IF you use 2 weights on the inboard and 2 weights on the outboard spaced 120 degrees opposing the heavy spot. Then you have an accurate Static and Dynamic Balance. Learned this when I was 16. That was 50 years ago. Always works. And just as accurate as any computer spin balancer.
Well if you learned that at 16, you didn't have a very good teacher. A bubble balancer is a SINGLE-PLANE balancer. It can only balance a wheel statically. The word gives it away. Static means stationary-not moving. The weight splitting he did in the video is to prevent COUPLE IMBALANCE, which happens when you add a single weight (over 3/4 oz) to one side only. Splitting the weight between one side and the other, exactly opposite of each other prevents that. DYNAMIC balancing is a TWO-PLANE balance. That means balancing the wheel while in motion. This is done on an off-car spin balancer. The wheel and tire assembly must be rotating to accomplish the balance in both the radial (up and down) and lateral (side to side) planes simultaneously. No amount of spacing the weights at a fixed angle (you mentioned 120 degrees) will accomplish this, plus it wastes a LOT of weights.
Yeah or maybe they are staying back so that everyone can see what he is working on, it totally would make sense if they were so close to him that he couldn't lecture it correctly or so close that nowone can see the lecture...
If the student with long hair is representative, a distinct lack of genuine interest displayed from her facial expression and body language. The lecturer at one point had to effectively tell one guy to pay attention. Maybe he wasn’t the best tutor in the world but he was parting with his wisdom built up no doubt over many years of crawling under cars in all weathers to “entitled” students none of which appear to be wearing overalls and ready to get their hands dirty. Maybe he was nearing retirement and couldn’t wait for the day when all he had to do was sit in his chair on the porch with his loyal dog, drink a coffee and recall the days long ago when student mechanics were keen to learn and swing a wrench. Nowadays we have technicians with plug in gadgets to do their thinking. These people weren’t expecting to actually lift a wheel without crane assist…..with their hands.😮 My technique was always to have the students do the work, one to adjust the balancer, another to remove the weight, make sure the wheel was free of debris, and so on each one having a task……in order to ensure their interest was retained. Maybe you no longer are able to do that…..in case they were to break their manicured nails. Let me assure you, it is soul destroying to stand with a group of ten students and know just two at best will be keen to learn,
