# NER EE-1 Nightmare with 936 teeth -part one...



## ralphbrades (Jan 3, 2008)

At last I feel that I am on the homeward stretch with this thing. The experiments are nearly complete and everything is coming together nicely. So, this morning I started the main production run. I mounted my rotary table on my mill and nearly lost a finger nail when it flopped down on me! Centred up the table on the mill with the two ivory inserts wound some tape around the bottom insert and press fitted a gear wheel. I calculated the offset for the mill, fitted a 0.25cm drill and selected HIGH on the gearbox. Unfortunately I have a captive dovetail head on my mill which means that I seem to spend most of the time winding it up and down on coarse and fine!












The table was turned 60 degrees between each hole (lots of winding...) and I have six holes per gear wheel. Each of the holes is going to have to be tapped to M3 -that is 36 tapping operations(!) The next operation on them is to drill out the 1.0cm hole to 1.5cm this is not a hard job -however the only 1.5cm drill I have has morse taper and to fit it into my pillar drill means that I have to remove the chuck and "wang" the drill into the hole. If the drill does not go "wang" then it often falls out...












The gear is clamped to the bed of the drill with a rubber tipped "Mole clamp". The main problem I have found with working with Hostaform is the fact that is seemingly explodes with a snow of white curls that are statically attracted to the nearest human being... This shows the centre of the gear being "opened out" with a boring bar to the seemingly unlikely, but critical, measurement of 2.6cm.













The main roller bearing sit in wooden pillows -these were cut from ordinary deal wood, (it was nearest!). 












The ends were then marked and chiselled to fit into the U shaped holders that had previously been fitted to the "spine".












The 3.2cm holes for the roller bearing where then marked out and cut with a hole saw. The pillow is quite firmly held in a G cramp -as the torque is really quite high...













The next shot shows the stages of assembly of the Bull Gear (from Right to Left) The roller race, the Bull Gear with its copper water pipe connector, and finally the bull gear with the axle and wheel fed through it.











regards

ralph


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## Torby (Jan 2, 2008)

I think I would have gone through a whole box of band aids (sticky plasters) by now.


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## dltrains (Jan 2, 2008)

Ralph, 
Really enjoying your build and think it's coming along great. Question. Though your pics are very clear and your descriptions leave little to be explained are the wheels attached to the axles or are they free. I can see that the gears are bolted to the snowflake so do you plan to allow the gearing to ensure syncronization? Hope that's clear. 

Dave


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## Jerry Barnes (Jan 2, 2008)

Anxious to see how this motor block goes together. I may be building a locomotive and I'm wondering how to do the axles and drive mech.


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## ralphbrades (Jan 3, 2008)

Dave,

You have got a little bit too far ahead! The snowflakes are connected to the Bull Gear via SPRINGS. The wheels are rigidly connected to the axle which "floats" +/- 3mm or +/- 5 degrees inside the copper pipe connection. Here is an early experimental shot.











There is no physical contact between the Bull Gear and the axle shaft, the ends of the axles will be held in roller races in the horn guides of the chassis.











No torque is transmitted via the copper water pipe connector -this simply acts as a location and spacer piece. The output shaft from the gear box which straddles the Bull Gear provides the torque to both sides of the gear. The wheels for the bogies are fitted with double ball races and they are free to move -even in opposing directions.











I hope this has helped?


regards

ralph


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## dltrains (Jan 2, 2008)

Thank you Ralph as that does clarify the last pic in the first post. Sorry to have jumped the gun but I really enjoy your builds. 

Dave


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## Les (Feb 11, 2008)

Intriguing.

Um, is there a .25cm HSS drill-bit famine across the pond? I'm amazed that you're getting any concentricity by 'whanging' that tapered bit into your chuck.









Howsumever, if you're happy, I'm happy. Great job! Those wheels are humongous! Did you have the gears cut, or did you buy them commercially?


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## ralphbrades (Jan 3, 2008)

Les, 

The gears are a commercial item £1.56p each. a 0.25cm drill is the correct size bit for M3 threading -the problem is the things go blunt so rapidly. Hostaform is a nylon with tiny grains of glass in it to improve wear characteristics. After I had drilled one gear I had to throw the drill bit away -it wouldn't have cut through balsa!!! 

I didn't fit the blacksmith's drill into the chuck -I have to remove the chuck and then 'wang' the drill into the Morse 2 tapered hole in the shaft of the pillar drill. The chucks for the pillar drill also use Morse 2 taper to fit. I follow my fathers instruction and "hit it with your shoe" to free the taper -except I use a cloth and hide hammer... 

regards 

ralph


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## ralphbrades (Jan 3, 2008)

At the end of another Sunday, I have completed my experiments -and driven most of the neighborhood cats wild with the screeching! 

This is Experimental Gearbox number 1.




















It is a simple lash up from bits of Matthews "Mecanno" -but it does prove the principle. The motor has a 20 tooth gear feeding the 40 tooth gear into the gearbox. A 10 tooth gear feeds a 30 tooth gear and finally a pair of 16 tooth Hostaform gears feed the Bull gear. 

And when I dropped it on top of the Bull gear -the Bull gear goes around and around!!!


The "production model" will have ball races holding the gear shafts -I am told that the squeak from the steel on steel is very noticable... I have decided to use 0.6cm PolyCarbonate sheet to make the gearbox from. It is light, transparent and strong.


regards

ralph


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## Havoc (Jan 2, 2008)

Good work Ralph. Nice to see a close-up of the wheels as well. They turned out very nice as well. 

One thing I don't get right now. I understand the photo of your drive is of the experimental setup, but with the arrangement of springs you use there, how are you going to drive backwards?


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## Torby (Jan 2, 2008)

Your server seems to be out. I'll have to come back later. Must be a mac-attack










That's a cool building set!


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## ralphbrades (Jan 3, 2008)

Sorry for the delay in getting back to everyone -but I have had to pry children away from the beach... 

Havoc, 

Six springs go clockwise and on the wheel at the other end of the axle six springs go anti-clockwise. The mid point of the springs is where the axle will "rest". There is enough "slack" in the springs for both forwards and backwards rotation. 

regards 

ralph


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## Torby (Jan 2, 2008)

That would help with rod binding too!


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## placitassteam (Jan 2, 2008)

Ralph, That is AMAZING!!!!


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