tools, materials & knowledge for model makers
The Burrell crankshaft and layshaft gears join the crankshaft to the differential and the differential to the wheels. The crankshaft gear was made from phosphor bronze and as you see in the video this slides so that you can select between drive and neutral. At first these gears look complicated, but they are actually quite … Read more
Originally I went with 20° for the miniature Burrell differential bevel gears. However, they are not right and bind up. Then I was contacted by JG who had made some calculations on the gears and sent them through. JG’s opening words were “Ah… Bevels are a different animal 😀 well mostly, and certainly with ‘Gear cutter … Read more
Prompted by Nigel showing how he managed to calculate an approximate 10:1 ratio gearing (which I considered far too complex) and the exchange of opinion, I shared an old project of mine with him. This led to his suggestion that a small article about my project would be useful here. I’m sure that there are … Read more
I worked out that I roughly need a 10:1 gearing, next I need to work out options for the Burrell 10:1 gearing. The gears are going to be 0.5 module with a tooth height of 1.1mm that would be 22mm at full scale. Probably the smallest gears I’m going to machine happily on a Sieg … Read more
I’ve been thinking about the Burrell gearing for some time. Calculating the overall ratio, estimating the maximum torque and speed of the traction engine. Looking online a Mamod TE1a traction engine flywheel speed is between 2000rpm and 2500rpm. 1st stage engine to layshaft is 4:1 reduction 2nd stage layshaft to rear wheels is 4:1 reduction … Read more
When cutting threads on the lathe we need to look at the change gears and pitch. The change gears on the back of the headstock that connect the headstock rotation to the leadscrew rotation along with the leadscrew pitch determine the pitch you will cut. The gears shown here on a Hobbymat MD65. The spindle … Read more
I’m looking at making helical gears, as per normal I wanted to start with the fundamentals. What is the optimum angle? Can I index them on the milling machine? Can I machine with a normal cutter? Why do I need to make helical gears? The big benefit is they will be quieter. Gear noise on … Read more
A review of the Warco HV4 4″/110mm Rotary Table. One of the main points to consider when selecting a rotary table is to go as big as you can within the limits of the milling machine that you want to use the table with. I have a small 3″ table that I have used with … Read more
Gear whine – Generated by meshing gears due to the vibration caused by failure of the rolling action between the mating teeth due to: Minute imperfections in manufacture of Tooth pitch circle (radius and centre) – see Gear Design Tooth involute form – gear profile error results in the generation of gear noise at sub-harmonics … Read more
Fundamentally there are a few different gear designs: Bevel Gear – Conical shaped gears, the angle between the input and output shaft is anything except 0 or 180°. Double Helical Gear – The double helical gear gives a much smoother still operation than the spur or helical gear and reduces the noise levels further. However, … Read more