Today I managed to get out into the workshop and complete the two gears that Thomas, one of my website readers, asked me to make for him. He intends to upgrade a electric Jeep for children increasing both top speed and torque by gearing and new electric motors. Hopefully Thomas will send some pictures and perhaps a short video of the completed jeep in action.
Back to the gears; I decided to grind a second tool with the tooth form and compare the results of both on a piece of scrap aluminum. Once this was done and the best profile found (as well as the number of teeth cut) I started on one of the brass blanks. The first gear was cut without too many dramas’s and checked against the gear it should drive. Everything seemed ok so the second blank was put into the chuck on the Vertex dividing head. Because the top of the teeth on the first blank could have had a better involute shape to the top of each tooth I decided to cut the second gear a little deeper, and this did improve the second gear slightly.
Rather than try and re-chuck the first gear and get to line it up (very difficult…) then take a slightly deeper cut I decided to take the top edge off each tooth with a small needle file. When testing both gears they seemed to work well enough so they should work fine.
Once the teeth were cut all that remained was to cross drill, then tap the hole for the grub screw. This was tapped 5mm because that was the smallest grub screws I had and the only deviation to the plans sent to me. Again hopefully this will not be a major problem and should offer better security than the 4mm asked for.
I will let you know what feedback I get for Thomas and whether I need to remake anything. As always….time will tell…………………
About Mike Freeman
Hello, my name is Mike Freeman and I am a retired Chief Fire Officer from the United Kingdom with a keen interest in model engineering, silver caddy spoons and sea fishing. I live in the pretty fishing port of Brixham, South Devon, in the United Kingdom.
I am a sufferer of degenerative osteoarthritis, which impacts on the amount of time I can spend in the workshop, and is the reason why you will see seats and a stool in some of the photo's. I have only recently added the above sentence after a discussion with one of my Doctor's from the excellent pain clinic, based in Torbay. This does affect concentration one of the reasons why I double then re-double my measurements and set ups.
Before completing nearly 30 years of public service I and my wife Sandy, owned and ran, a small restaurant in Okehampton Devon. Prior to marriage I worked for my father in his various businesses, in the early days these were garages, which he bought in a run down state, then built them up before moving on, to start again.
I took every opportunity in those early days, to work in his workshop's
learning 'on the job' rather than as an apprentice. This, I suspect, is the reason why my building various model's in the early days, turned into model engineering, when funds allowed the required equipment to be bought.
My workshop comprises one half of a detached double garage. It has a
stud wall separating the two halves and unusually perhaps, its own
shower/toilet/washbasin compartment! (the true reason for buying the
bungalow - don't tell the wife!!!)
It is fully insulated with a ceiling and fluorescent lighting supplementing the one window. Several double electrical sockets are dotted around in
relevant positions.
Equipment consists of 2 lathes (1 Myford ML 10 and 1 Chinese variable
speed motor with etched glass DRO's), 1 milling machine (RF25 far East) floor standing pillar drill, Proxxon bandsaw, Warco bandsaw, 6" wire brush and polishing mop motor, 6" coarse and fine grinder, Proxxon mini drill, various benches and an engineers vice. I have just acquired a third lathe, a Myford ML7 which I am at present evaluating so I can decide which of the Myford's I will keep.
I have only just bought the Chinese lathe and had it fitted with DRO's prior to delivery. And what a bonus they are! So good in fact that I decided to buy another set for the Milling machine. Whilst my engineering experience can only be described as limited, I find the use of DRO's has affected my accuracy levels which have improved tremendously (although that's not saying much!) and would recommend their fitting to any model engineer.
Prior to retirement I built for my son's 17th birthday a Locost car. This
was a tremendous project and a great feeling when it passed its test. The book it was based on suggests it can be built for £250. Ours was nothing special in the sense of all new parts but still cost about £900 to build!
