Power Cross Feed On A Myford ML7R

[Mexican jonParticipant @mexicanjon]

Does anyone know if a ML7R can be retro-fitted with parts from a Super 7 to provide powered cross feed?

I'd like to have the powered cross feed facility but don't really want to go to all the trouble of selling my lathe (Being that I have a screw cutting gearbox, clutch etc. on my lathe already) and then looking for a Super 7.

Regards Jon

[Mexican jonParticipant @mexicanjon]

[David Clark 13Participant @davidclark13]

Hi There

I would not sell my Myford ML7R either.

Your best bet would be to add a power X feed to the ML7R. I would think this is a very simple job.
Hang it all off a plate bolted under the cross slide bearing bracket.

Use a stepper motor and controller. There have been articles about adding a stepper motor feed to a mill and possibly lathes in MEW. There used to be an accessory that ran from a DC motor (low voltage). Look for Keith Ward's Myford ML7 rebuild, there may be a photo of the unit.

Have a look at the digital issues. You are a subscriber, aren't you? You are probably looking for articles by Tony Jeffree about converting a Myford ML7 to CNC. This would be a good starting point.

regards David

[dcostaParticipant @dcosta]

Hello Jon.

Searching the articles on “Converting a Myford ML7 to CNC” pointed by David, using
M EW_Indexes I find it in the following issues:

Year: 2008
Month: May
Issue: 138
Page: 28
Title: Converting a Myford ML7 to CNC Part 1
Key word: Leadscrew

Year: 2008
Month: Jun
Issue: 139
Page: 22
Title: Converting a Myford ML7 to CNC Part 2
Key word: Cross slide

Year: 2008
Month: August
Issue: 141
Page: 45
Title: Converting a Myford ML7 to CNC Part 3
Key word: Stepper Drivers and Control Hardware

Year: 2008
Month: September
Issue: 142
Page: 39
Title: Converting a Myford ML7 to CNC Part 4
Key word: Configuring Mach 3

Year: 2008
Month: October
Issue: 143
Page: 37
Title: Converting a Myford ML7 to CNC Part 5
Key word:

Best regards
Dias Costa

[David Clark 13Participant @davidclark13]

Hi There

I have set MEW 139 as the trial digital issue.

You can view this article in there.

regards david

Edited By David Clark 1 on 19/07/2012 10:13:27

[BazyleParticipant @bazyle]

Electric drill + tuning fork. 30 seconds job done. Seriously how often do you need power x feed.

[Anonymous]

Posted by Bazyle on 19/07/2012 11:10:29:

Electric drill + tuning fork. 30 seconds job done. Seriously how often do you need power x feed.

Actually all the time. If nothing else, it makes parting off a cinch.

Regards,

Andrew

[David Clark 13Participant @davidclark13]

Hi There

Electric power screwdriver would be ideal as a removable power feed.
The only time power crossfeed is useful is if you are skimming your faceplate and even then it could be done by hand.

Parting off with power feed? Not a good idea on an amateurs lathe unless you want a big bang.

Professional lathe with flood coolant yes.

regards David

Edited By David Clark 1 on 19/07/2012 12:03:07

[Mexican jonParticipant @mexicanjon]

Posted by David Clark 1 on 19/07/2012 09:08:31:

You are a subscriber, aren't you? regards David

 

I am now

 

Edited By Mexican jon on 19/07/2012 12:15:09

[JasonBModerator @jasonb]

I'm with Andrew, would not be without my power cross feed.

I have used the electric screwdriver method on the topslide when doing long tapered cuts, better than a cordless drill as the speed is slower & constant.

J

[Roderick JenkinsParticipant @roderickjenkins93242]

I fitted a commercial power servo motor crossfeed to my S7 lathe a couple of decades ago (Warrington Model something I think, sorry not close to the lathe just at the moment). I use it almost every time I'm facing – it is so convenient. My experience differs from David in that I almost always use it for parting off with a Greenwood TC tool in the back toolpost. Under power I can concentrate on feeding cutting oil into the slot and mild steel swarf comes off in nice tight little coils. I think one of the advantages is that one is less likely to increase the depth of cut until it all goes wrong, as you might do when hand feeding.

cheers,

Rod

[David Clark 13Participant @davidclark13]

Hi Mexican John

Does that mean you are a convert?

regards David

[Mexican jonParticipant @mexicanjon]

Posted by David Clark 1 on 19/07/2012 14:12:21:

Hi Mexican John

Does that mean you are a convert?

regards David

Not so much of a convert more like a returner.

Regards Jon

[john PettyParticipant @johnpetty96373]

THe ML7R can be converted to power cross feed, as long as the bed has the Long indent behind the leadscrew. I think all ML7R lathes have this. The bed of the ML7R is the same as the super 7.

Myford rationalised production so only one bed was used. The ML7R seems to be a super 7 without power cross feed.

John

 

Edited By john Petty on 25/10/2018 11:38:08

[Neil WyattModerator @neilwyatt]

Hi John, yes an ML7R has more in common with an S7 than an ML7, but you are six years too late

Neil

[john PettyParticipant @johnpetty96373]

Neil…………..

As I have only just looked at and sourced power cross feed for my ML7R. I thought it would add to any Model Engineers body of knwoledge that "YES" you can convert a An ML7R, plus any one who is thinking of converting their Super 7 should also check that the indent in the bed is there enabling PXF

So I may be 6 years late but in non of the other replies to this thread apperas to have given info given about putting a Myford PXF on the ML7R, but maybe no one is interested.

John

[Brian WoodParticipant @brianwood45127]

John,

I am interested, but I must ask—how do I recognise the long indent type of bed over whatever the other bed looks like to see if my ML7R can accept that upgrade?

I would have thought it more important to have the leadscrew with the keyway to drive the power cross feed than anything else

Would you mind clarifying please?

Regards

Brian

[john PettyParticipant @johnpetty96373]

Brian……………….

The indent on the bed on the lathe bed is crucial to retrofit Myford PXF to the ML7R. The Apron of the power cross feed models is quite complicated and there is a gear which sticks out on this apron further than the half nuts consequently even if the lathe bed could accomodate the new saddle, without the indent PXF is a no go.

The keyed leadscrew is imprtant yes, as that ttransfers the power, also there is a keyed cross slide screw which takes power from the apron to the cross slide via a gear on the new saddle.

To get some idea of this take a look at the following Ytube vids.

**LINK**

**LINK**

The end of the 2nd video shoews the gear which sticks out on the apron and you can get some idea of the indent from the first link.

Hope this helps.

John

[RobboParticipant @robbo]

Brian

Looking at your lathe in your album "Centring a long bar" it seems to have a bed compatible with Super 7 power cross feed, with a long indent below the front shear almost the full length of the shear.

[Brian WoodParticipant @brianwood45127]

Hello Robbo and John,

Thank you both for your helpful information, I did wonder if it was possible to be quantitative about this indent and take a reference measurement back, say, from the face of the front shear, it is largely a matter of judgement by observation otherwise.

The two links John listed were interesting, I was called away before I could finish the second one and will go back to it, but the lathe shown was clearly a hard worked machine getting some much needed attention.

Regards

Brian

[Martin KyteParticipant @martinkyte99762]

Before you do anything would it be worth giving Myford a ring, telling them what you have and asking them to quote for an exchange super7 with PXF. It is going to cost you some extra money but you may find it's worth it and anyway it costs nothing to ask. I did an exchange a couple of years ago and it cost me £3000. I exchanged a Super7 without gearbox for a recon Super7 with gearbox and power cross feed. I kept my stand, Newton Tesla drive and Motor and all my tooling. As you have a gearbox on yours you should do better than this On the face of it it may be a lot just for the addition of PXF BUT you do end up with a reconditioned machine (full regrind etc) and its going to cost you some cash to source the parts for upgrading your lathe plus the faff factor in actually doing the work.

regards Martin

[Brian WoodParticipant @brianwood45127]

Hello Martin,

I do have a second lathe with power cross feed, so this consideration was really more of interest than actually making a move in that direction.

I happen to like the Myford lathe I have, it is now nicely set up and suits me as well as having several other useful modifications of mine and to do an exchange has all the appeal of a forced house and workshop move We all know the feeling of dread that brings with it !!

So, thank you for the thought, you were not to know of the other lathe of course and it might be a suggestion that someone else might consider.

Regards

Brian

[Martin KyteParticipant @martinkyte99762]

Hi Brian. It did depend on the state of your current lathe. For me it was time to upgrade, I'd had my old lathe for 25 years or so and all my tooling and attachments (dividing heads etc) are built around the Myford so it gave me the ideal way of acheiving what I needed with flexibility and a way of keeping the costs within limits. I thought it may not suit you but worth adding to the consideration.

regards Martin

[John HaineParticipant @johnhaine32865]

As the owner of a late model S7 bought with PXF and converted to CNC, a few thoughts that may be helpful.

1. PXF is invaluable both for facing and parting. GHT recommended using PXF for parting and apparently used to give demos at MEX. My experience using a modern parting tool is that generally I can part at 200 rpm and slow feed with much less drama because the tool is working in its preferred regime, rather than the work going too slow in backgear and the nervous operator applying jerky feed.
2. I believe that converting to PXF is a bit more involved than you might think. First you need the keyed XF screw. This is larger diameter than standard. It may be that the old cross slide won't accommodate it – I base this comment on the fact that "CNCyourmyford" has to use an expensive 8mm ballscrew to fit the hole in the ML7 slide whereas I have been able to use a 12mm screw on my conversion. Also the OD of the feednut is larger and it's made of hard steel too. So it may be necessary to fit a new cross slide or at least drill out the hole.
3. Then you need the mechanism in the apron to pick up the feed from the key in the leadscrew and apply it to the keyed gear that drives the XF feedscrew – I think this will be a new apron or some complicated machining.
4. So if one wants to convert it seems to me it makes much more sense to use a DC or stepper motor to drive the feedscrew. In any case doing it mechanically is only a century or so out of date. A DC motor is probably preferred unless you have thoughts of converting to CNC or ELS later, since it's easier to preserve a manual drive as well. I'm sure there have been suitable designs in the mags.

[Mike PooleParticipant @mikepoole82104]

CNC your Myford have a beautifully made crossfeed unit for the CNC conversion. If you don’t fancy the cost it may give some ideas for a home brewed version.

Mike

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