Stepper driven spindle

[Kludge]

I did the continuity checks at the time but I don't recall what the outcome was.

No worries. 'Twas just a passing thought. I have them a lot. Sometimes I even remember what they were.

I'm at the age where I can barely remember breakfast.

There are times when this is a blessing. ;D

Best regards,

Kludge

 

[Mcgyver]

After reading this and taking a pass at Wikipedia (a good source for quick knowledge but not in any real depth) I got it!

definitely a indicator of superior intellect if you got it from that clumsy explanation.

here's a hobber in action - dedicated machine vs using the universal mill but shows the general idea
[ame]http://www.youtube.com/watch?v=acB1a9YILT0&feature=related[/ame]

Hobs are expensive and tricky to make - you have to relieve the cutter but maintain profile. Here's an amazing job Charles Lessig's done on a relieving mechanism -

[ame]http://www.youtube.com/watch?v=kJ8kyC_bpHs[/ame]

I'd be paranoid of movement when you harden it though. As I start down the path of working out how to put this on my surface grinder so i can grind after hardening, I gave my head a shake and decide I'll just buy the next gear i need .......or......

if you are thinking of diy gear making there's a half way house - not really hobbing but similar. it creates a facet tooth instead of smoothly generated tooth. I made some last weekend using this approach, they're a bit rough compared to a proper gear but serviceable for low speed low duty cycle stuff. Peter Harrison has an excellent page on this faceted way to cut a gear

http://helicron.net/workshop/gearcutting/gear_cutter/

 

[Kludge]

definitely a indicator of superior intellect if you got it from that clumsy explanation.

Or we're both on the same level of madness. I like that explanation better. ;D

here's a hobber in action - dedicated machine vs using the universal mill but shows the general idea

Ah, cool. When I went to the YouTube site to save that one, I discovered there are others on gear cutting so I have a rather broad lesson plan (such as it is) ahead of me.

Hobs are expensive and tricky to make - you have to relieve the cutter but maintain profile.

Does anyone sell them in reasonable sizes - ie, not of the industrial order more appropriate to locomotives?

I'd be paranoid of movement when you harden it though.

Grind, harden, temper then touch with stones to make it all pretty again. (He says looking at lots of hones & laps. )

if you are thinking of diy gear making there's a half way house - not really hobbing but similar.

Actually, this doesn't look all that bad. It certainly beats the individual tooth bit. Again.

While buying gears is certainly a logical choice and makes sense, since when did this hobby have to make sense? I mean, I asked elsewhere about MPT tapped valves and other fun things - as in where to make the acquisition of same. I could silver solder but ... 'know, what's the fun of that? And why would I want to know about ME and BA threaded goodies when I can manage number & metric sizes just as easily? The same holds true here; why buy a gear when you can make one?

Best regards,

Kludge

 

[Bogstandard]

http://www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Gear-Hobs

Bogs

 

[Kludge]

http://www.arceurotrade.co.uk/Catalogue/Cutting-Tools/Gear-Hobs

Cool, thanks! Hmmm ... about $45 each. All things considered, not too shabby.

Tools are an investment to me so paying a bit for these and the MPT taps & dies and other things I believe is worthwhile. I won't be able to do it all at once, of course, but one step at a time works.

With this is also doing my bit in helping the UK's economy. ;D

Best regards,

Kludge

 

[Bogstandard]

Kludge.

Not so much the UK, but China.

The advantage of hobs of course, is that you only need the one to cut the whole range of gears in that size, whereas with individual cutters, you have to buy the whole set to be able to cut anything you want if the specific size chosen, as they only cut a range of teeth for each sized cutter.

I added this, maybe not for your benefit, but others who might not understand gear cutting, as it can be a minefield, and full of gobbledygook jargon when just starting out.

John

 

[Kludge]

Not so much the UK, but China.

Okay, China too. But the shops are in the UK.

The advantage of hobs of course, is that you only need the one to cut the whole range of gears in that size, whereas with individual cutters, you have to buy the whole set to be able to cut anything you want if the specific size chosen, as they only cut a range of teeth for each sized cutter.

Ah, okay. I still need to do some reading and cogitating but *gasp* it's all coming together at a frightening rate. I am Learning New Things ... and that is ubercool!

At £22 each, I'm not likely to buy a whole great number at a time but in onesie-twosie quantities I think I can do it over a period of time. Just like the other madness I want.

I added this, maybe not for your benefit, but others who might not understand gear cutting, as it can be a minefield, and full of gobbledygook jargon when just starting out.

Some - a lot - is new to me too, at least doing it this way. Jargon ... comes with the territory. Adding more knowledge adds more of it, that's all.

Best regards,

Kludge the Student

 

[rickharris]

Light weight CNC mills and Lathes use stepper motors.

A stepper motor is little different to a brushless motor apart from the brushless having many more magnets and poles. they are both driven by Micro controllers producing a series of pulses to push the coil from one magnet to the next.

Larger systems often have fly wheels to smooth out the pulses - in the case of a HD the platter acts as a fly wheel.

Brushless motors tend to be lighter for a given power output and have better power efficiency.

Stepper motor size is in general limited by the magnets it needs to work. Unlike a motor that generates it's field from a coil.

Stepper motors are often geared to increase the torque.