Messages

71

General Mach Discussion / Re: CNC screw cutting lathe advice

« on: June 30, 2009, 12:38:15 PM »

Thanks for that; your machining centre looks very good. I have an existing manual mill (a converted Taylor Hobson engraver) with DRO but I don’t think it is suitable as the extra weight on the table could cause problems but also I think I prefer separate machine. Something like your machine would perhaps be a step too far as I am hoping to get up and running with minimal effort by me.

I also have an old Portass screw cutting lathe that might be worth converting that will allow me some funds to convert the mill.

I have been looking further into the ‘Electronic Lead Screw’ kit but I am concerned it only has limited facilities for other CNC turning such as form, diameters etc. I would prefer to go down the Mach3 route but I am hearing there are possible problems with screw cutting??

I am hoping to make some decisions in the next few weeks so I will keep reading and hopefully I can get system that will meet my needs.

Brian

72

General Mach Discussion / Re: CNC screw cutting lathe advice

« on: June 30, 2009, 06:53:18 AM »

Thanks fro that Steve; I am coming to the same conclusion regarding the Sherline. I am now looking at a WARCO http://www.warco.co.uk/Metalworking-Mini-Lathe-D4121A9297.aspx# and I have been talking to Lester from MEDW about fitting this system to it http://medw.co.uk/wiki/index.php?page=ELS+Price+List it means I will have to make some mountings for the motors etc. but it will be no problem. Also mit means I can source it all in the UK.

Do you have links to the asian lathes you mentioned?

Any thoughts would be appreciated

p.s. the drain plugs a re an off the shelf item I buy in.

Brian

73

General Mach Discussion / Re: CNC screw cutting lathe advice

« on: June 30, 2009, 03:13:22 AM »

Hi Al

I think this one should fit between centres on the 4400. But it is still something to bear in mind.

Brian

74

General Mach Discussion / Re: CNC screw cutting lathe advice

« on: June 29, 2009, 04:54:53 PM »

Hi Rich

Thanks for the reply. Probably the biggest thread would be M12 but mostly M8 and M10 with 1 mm pitch. It is for my busness www.ebolt.co.uk

The main problem I have is the time to retrofit to something existing. I already have a mill that I am trying to get round to converting to CNC.

The lathe I have posted the link to comes out at about £1500 plus. I already have a good old style lathe that could be converted but as i say I dont have the time to do it myself so another alternative would be to pay someone to do it for me.

Brian

75

General Mach Discussion / CNC screw cutting lathe advice

« on: June 29, 2009, 01:25:23 PM »

Hi All

I am not sure if this is the correct place to post but I am looking for advice on purchasing a small CNC screw cutting lathe/system. I am looking for something out of the box that requires minimal set up and it is mainly to be used for cutting stainless steel.
I have seen this system
http://www.cadcamcadcam.com/sherline4400-cnc35x17cncreadylathe.aspx
and they do a spindle encoder that allows cnc screw cutting but what do you guys think or are ther alternatives.

All advice much appreciated.

Brian

76

Building or Buying a Wood routing table.. Beginnners guide.. / Re: Size of a table..

« on: December 13, 2006, 12:13:20 PM »

Hi Art
Thanks for a great article; a couple questions though. Has anyone considered turning the table on its side in order to reduce the floor space footprint? I would have thought that as long as the table is slightly angled and some thought was given to the machining operation it could give many advantages. Do you know if anyone has done this?
Brian

77

General Mach Discussion / Re: Axis position feedback

« on: December 13, 2006, 04:40:57 AM »

Ron Rogers does a breakout that will error out if an encoder and the pulses Mach sends out dont match up. Not really closed loop but as near as you will get at the moment.
Hood

EDIT
 forgot to link to his site, www.rogersmachine.net

Thanks for the link Hood; this looks promising and as you say could be a good compromise.

Brian

78

General Mach Discussion / Re: Axis position feedback

« on: December 13, 2006, 03:07:14 AM »

Thanks for the quick replies guys.

I read the section on home position switches to give the initial starting position but was really asking more about positional feedback during operation. One way is via the use of a closed loop system (not supported) but I have also seen systems particular to stepper motors where a pulse or pulses are generated per revolution of the motor, a sort of poor mans encoder but I assume this is not supported either.
Thanks again for the answers and I can’t wait to get cracking on this project.

Thanks Brian

79

General Mach Discussion / Axis position feedback

« on: December 12, 2006, 04:26:33 PM »

Hi All

I just joined the site; I am living in the UK and am awaiting delivery of the following system
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ih=016&sspagename=STRK%3AMEWN%3AIT&viewitem=&item=260062146347&rd=1&rd=1
I am hopping to fit it to a ‘Taylor Hobson engraving machine but would like to ask the following general question.
Generally speaking how does the Mach software handle axis position feedback; I have done various searched on the forum but to no avail.

Any help very much appreciated.

Brian