Myford Super 7 Toolpost issue

[Matt Stevens 1Participant @mattstevens1]

Hi All,

So i just picked up a Myford Super 7B for a great price and with many accessories as well. It does have a quick change tool post holder, but its a real mini thing and will not accept 12mm tools which is most things i have!

I want to move the quick change tool post holder from my southbend lathe across which is much more substantial and of course will accept the 12mm / 1/2" tools…. trouble is, the height of the top slide of the Myford is such that with the holders bottomed out, i would not get to center height on the lathe!

How have most overcome this? I was hoping not to have to buy a new quick change system….

I can use the original tool post holder i guess, but thats like a down grade.

Open to suggestions….

[Matt Stevens 1Participant @mattstevens1]

[JasonBModerator @jasonb]

I think you will find most people use smaller tooling on the Myfords

[Ady1Participant @ady1]

Myford sized lathes don't really do 1/2 inch tooling

They do make good parallels

[John BaronParticipant @johnbaron31275]

Hi Guys,

I can use 1/2" inch tools in mine but much prefer 6 or 10 mm HSS ! Far less work profiling and sharpening !

[Andrew Moyes 1Participant @andrewmoyes1]

Look up the thread 'QCTP mounting on the Myford S7' and you will see some solutions.

[HopperParticipant @hopper]

Posted by Matt Stevens 1 on 05/05/2021 03:57:09:

I can use the original tool post holder i guess, but thats like a down grade.

Open to suggestions….

The original Myford 4-way toolpost takes 3/8" tooling, about 9.5mm. So 12mm tooling will sit too high in it.

[Ady1Participant @ady1]

Just picked up a Drummond M at the weekend and beside it was a Myford 7 which was waiting for another person to collect

It looked like what it was made for, a nice model makers lathe

[CirclipParticipant @circlip]

I feel the O/Ps pain, I have some perfectly good 1" (25mm) square shank lathe tools that won't fit in my Maximat.

Regards Ian.

[Matt HarringtonParticipant @mattharrington87221]

Matt, What QC system is on the Myford at the moment? You can get a suitable low cost QC system that takes 12mm at a good price on Banggood (and UK stock and thus quick delivery). You could then sell on your exsisting one….Just a thought.

Matt

[JasonBModerator @jasonb]

Matt although there are plenty of cheap QCTP about the problem with one that would take 12mm tooling AND fit a Myford is the bottom of the toolholder would only be about 3mm thick!

Not ideal for rigidity and likely to open up but sounds about right for Banggood

[Kiwi BlokeParticipant @kiwibloke62605]

Q: 'How have most overcome this?'

A: Well, by getting the right sized tooling… If you insist on using over-sized toolholders in a system they don't fit, make them fit! Mill 2mm off the bottoms off the toolholders. This is probably the most commonly-used solution, and, as you know, far cheaper than buying replacement tooling.

[Matt HarringtonParticipant @mattharrington87221]

Jason, the 250-001 holders are the same ones as sold by other vendors and to be honest, I have never had any issue with rigidity. In fact I also use a modified version of these holders on some of my Tripan toolposts, again with no issue. Matt

[not done it yetParticipant @notdoneityet]

Posted by Circlip on 05/05/2021 09:36:24:

I feel the O/Ps pain, I have some perfectly good 1" (25mm) square shank lathe tools that won't fit in my Maximat.

Regards Ian.

Reduce the dims of those cutters? I much prefer to reduce the cutter/cutter holder than increase the tool holder capacity.

[SteviegtrParticipant @steviegtr]

Have a look at a video i did a while ago on youtube. I explain & show how i made a 250-111 holder fit. Hope it helps you.

Steve.

Myford QCTP fitting for larger cutters

[Dave HalfordParticipant @davehalford22513]

Southbend to a Myford ………. Nope, still don't get it.

[Matt Stevens 1Participant @mattstevens1]

Dave – The Southbend i have is a 1939 Model C….so no QCGB, No reverse, no power cross feed, bed getting worn, no way to mount attachments to the cross slide (i.e. no T-bolts), less speed range, less tailstock feed etc. These are all advantages to the Myford which is much younger, in great condition and like i said – purchased at a good price.

Steve – I did watch your video, i see you machined down the top of the top slide quite a bit. I am not keen on that particularly, but perhaps modifying the tool holders is an option.

Jason – Understand your point about rigidity, however is it any different than using smaller tooling anyway? i.e. are they just comparable?

So it seems the main options are a) Buy all new tooling (expensive) or b) get a new QCTP suitable for a Myford with 12mm tooling or c) mill down my tool post holders so they will sit lower.

Perhaps option b) is the cleanest way to go and then when i sell the southbend, i can increase the cost by $100 to help offset. Any other ideas or am i concluding the right way?

[Mike PooleParticipant @mikepoole82104]

The top slide is superfluous much of the time so a bolster to just fit your tool post could be made. Refitting the top slide is a quick job when required. The potential increase in rigidity could help to maximise the cut taken with the larger tool bits. The Gibraltar tool post from Hemingway is designed to take large tool bits and maximise rigidity and depth of cut but only for a single tool.
Mike

[Michael BriggsParticipant @michaelbriggs82422]

I would not compromise the rigidity of the top slide to accommodate oversize tooling. I would either take Mike's advice, or reduce the height of the tooling.

Michael

[Matt Stevens 1Participant @mattstevens1]

Has anyone come across this solution?

**LINK**

Its advertised for the ML7, but i assume the topslide is the same between the ML7 and Super 7?

It also claims on this page that the slide can be milled to allow the usage of 1/2" tools in a QCTP….anyone seen these or got experience of them?

**LINK**

[Matt HarringtonParticipant @mattharrington87221]

 

These guys claim their topslide casing is used for all '7's:

**LINK**

 

I always thought the ML7 topslide was of a different size. I'd be interested to know for sure….

Matt

Edited By JasonB on 06/05/2021 12:24:38

[Matt HarringtonParticipant @mattharrington87221]

Jason, I'm interested to know why my last post was edited by you.

Matt

[Matt Stevens 1Participant @mattstevens1]

Hi All,

So i have been in contact with Myford and they have suggested i purchase the Myford ML10 QCTP kit…..apperently the only difference between the 7 series and ML10 QCTP is the relief that is cut out on the ML10 holder to allow them to sit lower. He said the website claims 2mm relief but in reality it is 4mm which is just enough to accommodate 1/2" tooling.

If the above it true, it makes for an east fix for any Myford 7 series….however i am still wary because i don't understand why they wouldn't just sell that one kit for all lathes promoting its advantage on the 7's.

[Matt HarringtonParticipant @mattharrington87221]

The only disadvantage is that the tool post needs to be oriented so that the holder drops below the level of the top of the top slide. This means you can't orientate the tool post to an angle – but you can orientate the slide – if that makes sense.

Matt

[SillyOldDufferModerator @sillyoldduffer]

Posted by Matt Stevens 1 on 07/05/2021 13:13:58:

…

He said the website claims 2mm relief but in reality it is 4mm which is just enough to accommodate 1/2" tooling.

If the above it true, it makes for an east fix for any Myford 7 series….however i am still wary because i don't understand why they wouldn't just sell that one kit for all lathes promoting its advantage on the 7's.

Myford/RDG would know for sure, but I suspect it's because they don't want to commit to anything outside the lathe's specification.

As Myford Super 7 lathes weren't designed or intended to be used with 1/2" tooling any customer who wants to do that is outside the normal support envelope.

For legal reasons suppliers are generally unwilling to take responsibility for modifications that might not work, especially if the amount of relief available on a bought in ML10 QCTP might vary from batch to batch.

Is there an engineering reason for wanting to fit oversized tooling to a small lathe? Though my Chinese lathe would take 1/2" shanks, I use 12mm. I've no desire to upgrade the machine to take 15mm tools. Expensive to do for not much return, if any.

As big knives are clumsy on small jobs I'm as likely to turn with 10mm tools as 12mm, and often get into small gaps with 8mm. If the work really requires 1/2" tooling, I suggest buying a bigger lathe. Then the whole machine is scaled to take the strain, not just the oversized cutter.

Dave

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