Myford Super 7 metric change gears

[Karl ManssonParticipant @karlmansson91253]

Thanks for the suggestion! I contacted Myford directly and got a not so helpful response. They don't make a 47 tooth wheel and they don't know where I could get one. RDG doesn't have one listed either. 45 or 50 but nothing in between.

Thank you Brian, that sounds like a bargain. What would shipping to Sweden come to?

Best regards
Karl

[SandgrounderParticipant @sandgrounder]

Posted by Karl Mansson on 14/08/2018 22:05:38:

Thanks for the suggestion! I contacted Myford directly and got a not so helpful response. They don't make a 47 tooth wheel and they don't know where I could get one. RDG doesn't have one listed either. 45 or 50 but nothing in between.

Thank you Brian, that sounds like a bargain. What would shipping to Sweden come to?

Best regards
Karl

HPC lists 47T spur gears, I don't know if they are in stock though.

http://www.hpcgears.com/n/products/12.spur_gears/spur_gears.phpV

[JasonBModerator @jasonb]

HPC gears are 20pa not the 14.5pa used on Myfords. 

Surprising what comes up when you put 47T Myford gear into Google. Home and Workshop also usually have a good selection of "odd" Myford gears"

 

Edited By JasonB on 15/08/2018 07:38:19

[Brian WoodParticipant @brianwood45127]

Hello Karl,

The tables are in pdf form which means I can email them to you, there are no shipping charges. I just need your email address which you will have to list anyway when making the payment to Paypal

You will need a 63 wheel for some of the gear set ups, the other gears used are all bog standard Myford gears, nothing 'exotic'

I'm sorry you got a less than helpful response from Myford, they aren't what the old company in Nottingham used to be I'm afraid

Kind regards

Brian

[Carl Wilson 4Participant @carlwilson4]

Just for interest my friend Richard Oakley can 3D print any gear you may require.

This is done using a FormLabs SLA machine. The print medium is a high impact resin similar to Paxolin.

[HopperParticipant @hopper]

Karl, if you try putting a "Wanted" advert on this website, you might be surprised at what turns up. I've had good luck that way with some Myford gears I needed in the recent past.

[SandgrounderParticipant @sandgrounder]

Posted by JasonB on 15/08/2018 07:32:44:

HPC gears are 20pa not the 14.5pa used on Myfords.

Surprising what comes up when you put 47T Myford gear into Google. Home and Workshop also usually have a good selection of "odd" Myford gears"

Edited By JasonB on 15/08/2018 07:38:19

Sorry about that, I always thought they were 20pa.

[Karl ManssonParticipant @karlmansson91253]

Brian, I will send you a PayPal payment! Thanks for the offer. Owning a Myford is very new to me so I don't have any experience with dealing with them Before. I was planning on getting some accessories such as a chuck and some collets from them. Going off topic here but seeing as you say they are not what they used to be, are the accessories they sell now Worth getting?

Carl, thank you! I will keep that in mind. Would he need a CAD drawing to do so or maybe he has files to work from?

Hopper, thanks for the tip! Somewhere along the road this lathe was separated from Everything that wasn't mounted on it at the time, including most of the changewheels. It's missing a few things, a steady rest for instance. The wheels I would need to buy to comprise a standard set are a 20, 30, 35, 38, 40, 45, 50, 55 and 70 tooth Wheel. To find just the ones I need in a Collection would be a long shot and buying them one by one from Myford directly sets me back about 150 Pounds. Doable but I'm looking for used if possible. I'll put up a wanted for them! Then there is also the 37, 47 and 63 tooth wheels for metric threads.

[Brian WoodParticipant @brianwood45127]

Karl,

I have sent you a PM

Brian

[Martin of WickParticipant @martinofwick]

Karl,

Worth looking at well known internet auction sites for change gears or sets of, usually cheaper than the supplier.

Nothing much wrong with the quality of stuff from the current custodians of the Myford 'badge', or their generic counterparts. However, you will pay a premium for ' badged' parts so you have to be choosy in what you want and ask if you can source for other places, make or adapt any accessories.

For example, I have used 3d printed PLA change gear set on an EW lathe (admittedly a small lathe) and individual ones (like 63)on the Myford. In fact I see no reason why you couldn't make and utilise a whole set of printed gears. obviously if you happen to be screw cutting all of the time there might be a longevity issue! There may also be an argument to have metal gears for your main x feed if you use that a lot but you will be surprised how tough printed gears can be, even in basic PLA (don't let them get too warm though!).

Even if you are the kind of animal that crashes carriages and regularly strips gears so what- just print yourself more gears for pennies and carry on stripping and crashing!

Alternatively, if you don't have a 3d printer, check out your local commercial printers and ask how much to print you a set in polycarbonate/nylon/acetal.

[Martin of WickParticipant @martinofwick]

HPC gears are 20pa not the 14.5pa used on Myfords.

Just out of curiosity, because I have genuinely no idea, would the difference in PA have any practical or noticeable impact on their occasional use for screw cutting?

I mean poor practice yes, increased noise or wear maybe, but in the context of an infrequently used change gear, would it really matter?

[Keith LongParticipant @keithlong89920]

Martin – for occasional use or in en emergency then you'd probably get away with running 14.5 and 20 deg pa gears meshed but running a pair like that together by hand you can definitely feel the "notchiness" as each tooth engages and disengages. I'm pretty sure that at some point the teeth are actually a slight interference fit the the tooth space on the mating gear. I suspect that they would pretty soon both wear together and become effectively an "intermediate" pressure angle. My feeling is that the "notchiness" could lead to poor surface finish on the job.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Martin of Wick on 15/08/2018 14:09:04:

HPC gears are 20pa not the 14.5pa used on Myfords.

Just out of curiosity, because I have genuinely no idea, would the difference in PA have any practical or noticeable impact on their occasional use for screw cutting?

I mean poor practice yes, increased noise or wear maybe, but in the context of an infrequently used change gear, would it really matter?

.

For the purposes of occasional, light, screw-cutting … yes, you would 'get away with it' BUT it's a rather nasty thing to do to innocent, well-brought-up gears

It's worth having a look at the animation featured on this thread: **LINK**

https://www.chiefdelphi.com/forums/showthread.php?t=129632&page=2

MichaelG.

[Andy AshParticipant @andyash24902]

I recently had call to cut a 2.5mm pitch thread using my Super7 QC box. I knew about this forum thread from way back and already knew which gears I would need to make the metric thread. Back when I figured it all out I didn't know what metric thread pitch I might want to cut, so I always assumed I would buy an involute cutter when I needed one to make the required gearwheel.

With Coronavirus and the supply shortage I have discovered that the correct involute cutters aren't easily available, nor are the gears. I had always assumed that my ordinary PLA filament 3D printer would not make a gear strong enough for metric screwcutting on the Super7.

Pressed by shortage of availability I gave the idea a try despite thinking it wouldn't work. I can report well of the results. I was easily able to cut an accurate 1.5mm pitch internal ACME thread, into a mild steel bush. It's a substantial thread and quite a long job, but the 3D printed PLA gear shows no sign of distress at all. I still wonder if the oil will affect it in storage, but even if it does I can just print another one.

If you're thinking this isn't worth the effort I can assure you that it very much is. I don't think I'll be making gears any longer unless it is for a model where the material actually matters for cosmetic reasons.

Edited By Andy Ash on 25/11/2021 19:46:42

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