Collins

iTrader: (1)

Hiya Ashley,
I'm in the same boat as you then, I work as a Mechanical design draftsman. I was going to start drawing up something over the next few days and transpose the DWG files over to Solidworks. My email addy is [email protected]
Cheers mate...
Ciaran Whelan

Ashley Cobb

iTrader: (28)

I have autocad and am slowly learning solidworks - considering its only a hobby its a bit of stretch currently - and the poor old laptop has a very hard time running solidworks

Tom

Real lathes use one motor and run the feed's of the leed screw. This alows feed's to be adjusted with rpm of the job hence feed rate is measured in mm per rpm mm/rpm.


For your purpose you maybe able to get around this as a tires finish cut size (race size) only changes a few mm, you could calculate the correct feed and speed and set your true at this (make speed non adjustable). When your roughing down from new size the quality of the cut shouldnt matter.

rpm = (300 x cutting speed of material) / dia.

Collins

iTrader: (1)

Hi Ashley,
I have just done my advanced Solidworks a few months back, and it still doesn't help. Kidding.... If you need some help on solidworks, I might be able to help there. What version are you running?

Tom, for ease of the project, this will be twin motor. I do know what you mean with regard to lathe mechanicals.

I might need someone to do some maths for me though.
I want to know the speed of a threaded block moving up a typical M8 or M10 threaded rod if the motor were to be spinning at aprox 1000rpm.

Regards,
Ciaran Whelan

Tom

Well that would have to do with the pitch and the number of starts for the thread.

Standard m10 is 1 start with a 1.5mm pitch (of the top of my head) so your block would move 1.5mm per rotation. So 1000rpm x 1.5mm = 1500mm/min

so you will need to slow that down quit alot. Also worth noting is metric fine thread. Little harder to get but this what is used in like comm lathes and adjustment screws etc...

For the reasons above the finer pitch will slow the movment. Im guessing but m10 fine has a 0.8mm pitch.

Collins

iTrader: (1)

Ok... now we are talking. I should have worked that out myself. I might be able to source M10 fine stainless, I will call into an engineering supplies on my way home. If I use the .8, what is the travel speed? Bear in mind I have a variable speed circuit that I collected at lunch time.

Collins

iTrader: (1)

I am just thinking out aloud now, but I might try collect some 8mm rod and 8mm bronze bushes. I have all the electronics collected at lunch time also.
The screw motor has 1.4kg torque @ 1200rpm and the Main drive motor has 4.3kg torque @ from memory something stupid rpm (high) will confirm this tonight as the motor is downstairs in the car.. Nearly home time and I will get measuring everything I have

Tom

I would run some reduction for the feed motor to slow the feed down something like 10;1
so with 10;1 reduction
~ 100rpm x .08 = 80mm/min so will pass a 30mm wide tire in 20 seconds or so.

For wheel speed would think 700rpm or more with a carbide cutter.

Slippery

iTrader: (1)

All of the Hudy truers i have look at have used the simple Starter motor like you would use to start aeroplanes, the wheel adapors will clamp straight to the shaft motor for the cross feed Jaycar had some 12v motor gear box units of various ratios look under the Mechatronic section in general components these look identical to the hudy units also

good luck

Eggyolkeo

iTrader: (11)

I'm not into on-road so can't help you, but just wanted to say good on you for giving this project a go. I can't believe the negativity earlier on here.

Often projects like this are not always done to save money, but are rewarding if a solution can be reached.

Good luck!

Collins

iTrader: (1)

Thanks Slippery,
I bought both motors from Jaycar, darn it, where is my jaycar catalogue when I need it!!!! hehe... I did however see the little unit you refer to today, but when I saw the actual setup I thought it looked too light weight. (as in very flimsy)

I called into fasteners Australia on my way home, and picked up a 1/4x3 UNF threaded rod and tap set, also called into my local steel merchant and collected a bundle of offcut alloy plates of different sizes.
So... Tom if I can call on to your maths again please, I have checked the smaller motor and it has 1.3kg of torque @ 6500rpm.... So a bit of reduction will be needed, but fortunately for me I have the 2 mosfet speed controllers.

Collins

iTrader: (1)

Good on ya Eggyolkeo... thats the spirit.

Ashley Cobb

iTrader: (28)

I'm thinking alot less complicated for the design I'm thinking of.

I don't think I'll be much help to you. Good luck though

Collins

iTrader: (1)

No problem at all Ashley...
Try do something, you never know, you might have something in mind that might make my idea look miniscule...

Nitro$junkie

iTrader: (7)

HEHE hook line and sinker