Cnc Gear Hobbing Machine

[newport]

Hi i wanted to build a cnc gear hobbing machine, im new to cnc, but i have manual gear cutting machinery, does anyone know of any hall effect circuitry and software to make the cutter & gear to be cut turn in relation to each other?

[Mcgyver]

why would you want hall effect stuff? there's an example around of making a cnc gear cutter with a horizontal mill, more properly a universal mill so the table can be turned to the helix. it was done by putting an encoder on the arbor, the 4th axis being a rotary table driven by a stepper motor. the electronics takes the signal from the arbor and drives the stepper, thereby determining the blank's speed

http://homepage.ntlworld.com/stevens...0indexer16.jpg

[newport]

Thenaks mcgver, i just saw some someone else use hall effect, what sort of program would i have to use to control the indexing head? I want to convert an old lathe for cutting long spline shafts.

[Mcgyver]

duplicate

[Mcgyver]

so far as i know it was home brew, but i may be wrong. John Stevenson who posts on the home shop machinist bbs site was the creator, that's where i saw it. my Q on the hall effect wasn't completely rhetorical, for all i know there is a great way to use them for that - I'm the opposite of an electronics expert. also, there was an article in MEW (model engineers workshop) that dealt with circuitry etc to divided encoder pulses into stepper pulses.

[RICHARD ZASTROW]

Newport, Coincidentaly, I'm in the process of designing a spline hobbing machine right now. I'd be happy to help if I can, so long as I don't compromise my agreement with my client.

Send an email to r.zastrow@sbcglobal.net FYI we just completed a conversion of a CNC Vertical Mill to a spline hobber. This is a commercial machine with a 6-axis PC controller. Head swivels for hob angle, Vertical travel for hob shift, second vertical travel for hob position, cross travel for in-feed, longitudinal workpiece feed and rotation of workpiece. At any time, all can be synchronous. All done with clients proprietary software because I'm fair at mechanicals but an electronics ignoramous.

[Nzoldun]

The magazine you need is issue 108 of thr (UK) Model Engineers Workshop, pp30-34. If you cannot obtain it in Aus., send me your e-mail address. I will help if I can!

[RICHARD ZASTROW]

Newport, I received your e-mail without your e-mail address. If you want me to e-mail you please send address.

You mentioned in your #3 post above you wanted to use the project machine to cut long splined shafts. It would be far less complicated (fewer $$$) to convert to a spline miller vs. spline hobber. Instead of a headstock with a synchronized rotary axis the hob requires, a simple indexer with a spline form cutter would suffice. You could automate the remaining functions with a sequencing control (relays, programmable controller).

Remember you will also probably need a follower rest to counter sag, vibration and deflection from cutting forces.

Keep thinking about it and I'm sure you will get there. Please send e-mail address.

[newport]

My email address is newport@globaldial.com, i want to make it a hobbing machine because i already have a full set of hobs, and if i made it a spline miller i would need lots of individual form cutters. With the lathe i already have the travelling steadies and the carriage is fitted with a one way clutch which is good for anti backlash.

[newport]

Hello Richard, how did your spline hobbing machine go?

[RICHARD ZASTROW]

Newport, The mill conversion is in a production shop hobbing simple splines.

The build from scratch new machine design is finished (subject to clients whim and subsequent engineering changes).

Order is pending (heard that before) lol

This is not a DIY machine. Base alone weighs 13,000 lbs (5900+ kg.)

Hows your lathe conversion doing? BTW, my hard drive failed and I lost your e-mail address. Send again? to r.zastrow@sbcglobal.net

Dick Z

[newport]

hey Richard, havent got around to doing the conversion yet, im thinking now of single indexing, using a division master and making a milling head. my email is newport@globaldial.com and the website is www.newportgears.com.au