Geared Saddle wheel Myford S7

[Martin KyteParticipant @martinkyte99762]

[Martin KyteParticipant @martinkyte99762]

Hi Chaps

Anyone fitted a Meek Saddle travel geared handwheel dial to a Myford Super 7 with power cross feed. Took the old one off my non PCF and am probably thinking I need to dismantle the apron to fit it on the new lathe. Not sure I feel happy drilling and tapping a blind hole in the front without some idea of the casing thickness. Be helpful just for the hints and tips for apron dismantling/assembly alone.

regards in hopeful expectation

Martin

[Robert ButlerParticipant @robertbutler92161]

Dear Martin i recently replaced my metric geared hand wheel with an imperial version by Steve Tracey which i understand is to the Meek design. The lathe is a Super 7 with power cross feed and was in effect a substitution of items. The device was held in place by a single screw which i took to be a filler/level plug as originally fitted? is your lathe fitted with a filler/level plug? Does anyone require the metric version? Robert Butler

[Martin KyteParticipant @martinkyte99762]

Ah, that's interesting. I shall have to do some further inspection. It would make sense to use the tapped hole for the oil level plug in the design although just from memory I thought mine had a hole at 12 o'clock but that could be just me. certainly on the non PCF version I had to drill and tap for the retaining screw. I will report back (eventually).

regards Martin

[Robert ButlerParticipant @robertbutler92161]

The filler/level plug is located at about 9 o'clock on mine?????. Apart from the datum mark on the barrel which is best at 12 o'clock the location of the fixing screw is irrelevant. the law of sod could however intervene and the hole in your existing hand wheel mounting could be in the wrong place and not line up with the filler plug. When fitting don't forget the thin card spacer before securing the hand wheel to ensure clearance.Regards Robert

[LambtonParticipant @lambton]

Martin,

I fitted one of these to my imperial Super 7 with PCF about two years ago. It is without doubt the most useful accessory I have bought or made for my lathe. It is very accurate and most convenient to use. Fitting is a doddle and removing it periodically to put oil into the apron takes about 5 minutes.

[Mike CrossfieldParticipant @mikecrossfield92481]

Martin

Graham Meek's design drawings show a backplate with alternative fixing holes for machines with and without PCF. If you have a commercially produced handwheel you may find that both fixing holes are present. As already pointed out, no drilling of the lathe apron is necessary for PCF machines, so at the very worst you may need to drill a hole in the handwheel backplate to align with the oil filler plug.

I made one of these handwheels last year, and it is an excellent addition to the lathe. I use it all the time, and would now be lost without it.

Mike

[Neil WyattModerator @neilwyatt]

Graham Meek has heard of this thread and sent me a message to point out:

"There is a chance that the last lathes produced by Myford before their closure had a different PCF Apron filling arrangement. I seem to recall seeing a "Zerk" fitting used instead of the "oil filler screw", but I cannot be sure."

Neil

[Martin KyteParticipant @martinkyte99762]

OK, so I had a proper look last night and you are all correct in that the back plate is counterbored for the oil level screw to be a direct fit.

However the pinion shaft needs a 4mm tapped hole down the end to take the retaining screw. So two options. Strip the apron which as I have just got the lathe I am (probably illogically) reluctant to do or turn up a sleeve with a cross drilled and tapped hole to fit the shaft with a tapping size hole up the end to act as a drill guide and do it in situ with a hand drill. The shaft would be prevented from being pushed back into the apron by the sleeve and its grubscrew and locking the saddle will prevent rotation.

I will have a go tonight.

regards Martin

[steamdaveParticipant @steamdave]

What is the advantage of the Meek apron handwheel over the leadscrew handwheel? Both are graduated but the leadscrew is lower geared than the rack and pinion, so (in my opinion) is more precise when turning to a length.

Dave
The Emerald Isle

[LambtonParticipant @lambton]

Martin,

No need to dismantle the apron.
Make a drill bush with an 3.3mm though hole and a concentric blind hole that is a nice fit on the pinion shaft – No need to make any form of locking provision.

Lock the saddle to the bed to prevent the pinion turning then make a short piece of wood to fit tightly between the end of the pinion and the lathe bed just below to rack to prevent the pinion moving back.

Drill the 3.3mm end hole with a normal battery drill tap the hole and the job is a "good un".

Hope this is of help.

Eric

[Mike CrossfieldParticipant @mikecrossfield92481]

"What is the advantage of the Meek apron handwheel over the leadscrew handwheel? "

1. The apron handwheel dial can be zeroed at any point, and is 1.00 inch/rev

2. The apron handwheel is more conveniently placed than the leadscrew handwheel.

The leadscrew handwheel calibration is more accurate than the Meek handwheel, but for most of my work the apron handwheel is good enough. Out of interest I checked the calibration against the leadscrew handwheel over several inches of travel of the rack, and it was within +/- 3 thou.

Mike

[Martin KyteParticipant @martinkyte99762]

Hi Eric

The reason I think I need to lock the bush onto the shaft is you can't get to to the rear of the pinion as it's a power cross feed lathe. If you push the pinion inwards you end up shoving the plastic plug out of the casting. I could as you suggest wedge the plug with a bit of wood but if I fit a grub screw the shaft will be retained in the same manner as when the traversing wheel is in place. I could just do it all by eye before I take the wheel off. The shaft has a centre in it so it's only the axial truth that needs care but to my mind that lacks finesse.

Regarding the usefulness of the device, primarily I would say it is the ability to zero the micrometer which you cannot do with the graduated leadscrew handwheel. This also makes it easier to knock the feed off on a length when using the self act as well as standing in front of the lathe being a more natural position to operate from than 'up the end'.

Once this bit's done I need to reinstate the micrometer dial on the tailstock (George Thomas version) and dowel the topslide and fit a lockscrew, then I am back to normal. Probably do the leadscrew bearing mod too as I have all the bits. On the last lathe I had a stepper drive to the leadscrew so the Handwheel was replaced by a toothed pulley which was the incentive to get the geared handwheel in the first place.

PS just read Mikes post as I was writing this so I concur with him (not only that I agree an all)

regards Martin

[LambtonParticipant @lambton]

Martin,

My lathe has a power cross feed and I "jammed" the pinion against the lathe bed as described.

Other advantages of the Meek handle is that being on the saddle is very easy to see whilst the work is in progress unlike the lead screw hand wheel dial (virtually impossible on a long bed lathe). Also it works all the time with no need to engage the half nuts.

Eric

[John Stevenson 1Participant @johnstevenson1]

Posted by Mike Crossfield on 07/12/2016 11:16:32:

"What is the advantage of the Meek apron handwheel over the leadscrew handwheel? "

The leadscrew handwheel calibration is more accurate than the Meek handwheel, but for most of my work the apron handwheel is good enough. Out of interest I checked the calibration against the leadscrew handwheel over several inches of travel of the rack, and it was within +/- 3 thou.

Mike

If you work the maths out on standard Myford gears and rack each full revolution of the handwheel moves the carriage 0.861805"

Using Grahams 4 gear ratio's of 26 / 28 : 26 / 28 that works out to 0.86224489" or a difference of 0.00043989"

So basically 1/2 a thou per rev.

The metric version using 29 /31 : 29 / 31 is very slightly worse at 0.00046"

However in my pending tray among a lot of projected projects is a simplified version that I made for a CVA and later modified to fit the Myford.

This design only uses two gears and has an error of 0.000268"

If you add a third gear you can run two dials, one imperial and one metric at the same time with the metric one having an error of only 0.00009"

Don't ask for the design, it will be done but I have far more important design work to do for the Chinese first.

That's what pays the bills.

[Steamer1915Participant @steamer1915]

Hello Martin,

Below is a copy of the drawing of the jig that I recommend when drilling the original shaft. This drawing is included as part of the fitting instructions that I supply with the dial. You pretty much have the same idea. I will also include a paragraph from the same instructions:-

"Whilst the majority of Power cross feed machines will be able to utilise the apron oil level screw to anchor the back-plate to the front of the apron, some of the later machines have the oil level screw positioned to the left of the earlier placement. In such cases, the dial should be fitted as per the non-PCF versions. It should be noted that there may be an issue with the wall thickness of the front of the apron casting and therefore it may be necessary to drill the tapping size for the M4 thread to a depth of only 8mm. This will prevent breaking through into the cavity and subsequent contamination of the oil. In this instance, it will be necessary to slightly shorten the 16mm long M4 cap-screw so that it grips the back-plate before becoming thread-bound at the bottom of the hole."

Hope this helps,

Best regards,

Steve.

[Martin KyteParticipant @martinkyte99762]

Thanks for that Steve. That's exactly what I came up with. Do I assume I bought the thing from you. I really have no idea except it was purchased at Harrogate one year. I don't have the fitting instructions any more but I may have subliminally remembered the bush. I'm pretty sure I drilled and tapped my last pinion shaft in the lathe. As I wrote previously the back plate is already good to go on the oil filler tapped hole. It's a Myford reconditioned lathe so I'm not sure how much they have re-manufactured. I'm pretty certain that they made a new tail-stock base. Difficult to see how they could have maintained the centre hight without doing so. The apron may also be new stock too.

regards Martin

[Steamer1915Participant @steamer1915]

Yes Martin, you bought it from me at Harrogate in May 2014. You were number 57 according to my records. I have now sold over 130 with a recent flurry on eBay.

I have modified the fitting instruction sheets with some supplementary notes about fitting to the PCF versions and later lathes with the different screw placement.

I hope the dial continues to give you good service.

My best regards,

Steve.

Edited By Steamer1915 on 07/12/2016 15:24:28

[steamdaveParticipant @steamdave]

Posted by Mike Crossfield on 07/12/2016 11:16:32:

"What is the advantage of the Meek apron handwheel over the leadscrew handwheel? "

1. The apron handwheel dial can be zeroed at any point, and is 1.00 inch/rev

2. The apron handwheel is more conveniently placed than the leadscrew handwheel.

The leadscrew handwheel calibration is more accurate than the Meek handwheel, but for most of my work the apron handwheel is good enough. Out of interest I checked the calibration against the leadscrew handwheel over several inches of travel of the rack, and it was within +/- 3 thou.

Mike

Thanks for your assessment, Mike. I'll just continue to use my present setup.

Dave
The Emerald Isle

[Martin KyteParticipant @martinkyte99762]

Done and dusted. The fiducial line ended up at 1 o-clock but I'm not overly bothered by that, it's very comfortably in my eyeline. The thing that I like most about this addition to the lathe is that it looks like it should be there and fits in very well with the overall design of the lathe. Thanks chaps.

regards Martin

[Steamer1915Participant @steamer1915]

Martin, Glad that all has gone well.

My personal preference is to have the line at the 12 o’clock position.

It was intended to mark this during production of the dial but unfortunately, there is a slight difference in the angular positioning of the back-plate between the power cross feed version and the non power cross feed version. Therefore, a pre-marked line may be in an inconvenient position for the lathe user. Position of lighting can be a big factor.

Best regards,

Steve.

[Martin KyteParticipant @martinkyte99762]

Hi Steve.

It's no reflection on the dial that it worked out like that. I suspect the apron is a new manufactured component and they maybe required the oil level slightly higher. They have at least retained the radial separation from the pinion spindle centre to the oil level screw. It's not moved much because the relieved sector on the back of the dial plate still provides clearance for the end of the rack pinion and I doubt that has moved. It's really not worth either shifting the line or re-machining the back plate just for the sake of moving the datum less than 30 degrees and realistically you would have to do both. With the power cross feed the cross slide leadscrew bracket is longer so there is a natural tendency to peer round it rather than directly down. As with most things, give it a week to get used to it and it would seem weird to have it any other way.

regards Martin

[Steamer1915Participant @steamer1915]

Hello Martin,

No worries. All I was trying to point out is that there is a difference between the angular positioning of the countershaft (as you have correctly alluded to) between the Non PCF (your original machine) and the PCF (your present machine) models. That is why I don't mark the back-plate and leave that to the customer. I would imagine that even if your apron has been re-manufactured, the angular positioning of the countershaft would remain the same.

My best regards,

Steve.

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