Myford question

[andrewtoplis]

Hi Guys, novice question here so please be gentle.  I've looked through at least the first 10 pages of this sub-forum and couldn't find this, so apologies if it has been posted before ad-nauseum.

I've just brought home K1878, which the Myford site suggests is an early ML7, bought from a gentleman in Sevenoaks.  I've not had time to set it up properly yet, but did check that the carriage and slides move freely and smoothly, however the carriage handwheel appears loose as shown in the short video here.

Secondly the carriage is notably stiffer towards the tailstock end of the bed.

Any advice what this could be?

Thanks in advance, Andy  


www.flickr.com/photos/191005105@N06/50587282476/in/dateposted-public/#

[uuu]

Wear.

I didn't use the carriage handwheel when cutting on my old Myford - just the leadscrew. So play wasn't an issue. You could strip the apron down and re-bush it - but the shaft may also be worn, so might need sleeving. See this exploded diagram (which may not be for your lathe, but it will be similar)..Myford Apron

The carriage being tight at the tailstock end is also wear. You could re-grind the bed, but just living with it is probably the way to go.

Don't fret. Many a fine model has been made on a old Myford - it's how you overcome these challenges that makes the hobby fun.

Wilf

[andrewtoplis]

Thanks Wilf. It looks like the end of the rack pinion assembly (number 11 in that diagram) may be slack where it meets the apron. That seems to be the piece to the left of the handwheel that moves when the handwheel is moved...?

[uuu]

Aha, I had misread the drawing. But yes, both those shafts may be sloppy in the casting. As long as they don't jump teeth, they can be left alone. Otherwise you could see if it's the shafts or apron casting that's worn (or both) - and bush/sleeve as appropriate.

Wilf

[dscott]

You can see the shaft moving!
I was lucky with my two that they have not had much work during their lives!!!

Stop laughing them in the KNOW!!!!
See my Rescuing a Super 7 on here!!!!

I will go and have a look at a dismantled one!!!
3 off 3/16" Allan cap heads hold the little gearbox in place.
BUT.
You will need to take out the leadscrew.
And unbolt the Apron to get at it.

When these machines were being sold there was a sort of Life Expectancy and after a few years they expected you to return and buy another!
A bore out and bush fitted would work wonders.
The rear is machined flat so that is half the battle.
I almost said you could mount it on the faceplate and bore it out!!!
Only you can't.

David and Lily.

[92220]

Hi Andy.

The handwheel shaft runs in a bronze bearing, which is not very long. It wears quite quickly so gets sloppy very quickly. Not a major problem as long as the teeth stay engaged. As far as the tightness at the tailstock end goes, that is solely due to bed wear. If you can afford get the bed re-ground, that will sort it and make it like new. If you do want it reground, I had a company regrind my Senior mill, at a very good price. If you want to go down the re-grind route, I will try and find the details.

Bob.

[ettingtonliam]

The reason its tight at the tailstock end is that most turning is done within 6" of the headstock, so that where the bed wears. Unless you intend doing a lot of long shaft work, just live with it. Its not just getting the bed ground, its all the other work that has to be done to re face the saddle where it fits on the bed, etc.

[andrewtoplis]

Thanks for the replies Wilf, David, Bob and Liam - the consensus seems to be 'just get on with it'!

Bob 92220 - yes the gear stays engaged and the carriage moves happily enough, the further it goes to the tail end the less 'slack' in the handwheel shaft there is which suggests to me the rack is worn at the head end as well - no surprise.

I'll crack on with getting it installed, build an engine then look at getting it re-ground in a couple of years time.

[andrewtoplis]

Out of interest guys, would a super 7 apron be interchangeable with.an ML7 one?

There is a super 7 one on eBay for about £30, and I'm conscious mine seems to be quite worn.

[dscott]

I will go and do a measure in the morning for you as mine is off at the moment for total rebuild and PAINT.
You may be in luck because it would make sense for Myfords to do this.

David and Lily.

[uuu]

Lathes.co.uk suggest the ML7 apron is aluminium but the Super 7 is iron. But no mention if they're the same shape. They do look very alike in the pictures.

Wilf

[92220]

When I was an apprentice, back in the mid 1960s (!!), we had a M7 and 2 S7 in the experimental workshop. They all had cast iron aprons in those days and in any case it doesn't really matter what material the apron is made from, as it is the part that hangs down the front, and only has a few bearings fitted for the various shafts that run in it. the material may have changed on later models, but I would have thought unlikely, as cast iron aprons would be quite a bit cheaper than aluminium ones. You can't be sure of whether a secondhand saddle from a S7 will fit as the S7 bed width changed at some time, and was made wider. I think the alteration coincided with the time they introduced the power cross-slide.


Bob.

[andrewtoplis]

Hi guys
Many thanks for the replies, handily the chap was also selling an ML7 one as well so I grabbed it. Looking at the pictures on eBay the S7 one appears to have five screws on the top Vs 3 on the ML7 but I couldn't say for sure! Cheers again!

[dscott]

Here bit is and may be useful in the future.

Lovely way of doing a transfer that only Engineers would appreciate.
Dirty fingers required.

Yes I have 2 Super 7s one in bits and very rusty.



David and Lily.

[goldstar31]

Following some other bright spark in the firmament elsewhere( so he thinks), I am reminded that there are at least TWO different diameters on the leadscrews even on the old lathes. So check on that before going in to thev rest of the hysterics. Maybe use one of the lathes to replace the worn bits on the saddle assemblies.

Best Wishes

Norman

[andrewtoplis]

Here I go again then.

I managed to get some time to set the machine up properly today (first shed time for ages). First we lifted it out of the shed and took the opportunity to give it a bit of a clean up round the back where I can't normally reach. Then bench drilled, machine returned and bolted down lightly, plugged in and switched on, result - no movement, a loud buzzing then smoke from the motor....

The lathe turned over in the seller's garage, and it ran a few weeks ago here when plugged in for a quick demonstration. It turns over by hand with some resistance.

I'd really hope that the motor isn't beyond repair...does anyone have any advice?

Andy

[coniston]

Hi Andy I think someone had a similar problem maybe with a Myford or Boxford. Try searching for posts including these names and Motor. Your motor probably has some swarf jammed in the windings or similar. I suggest a strip down of the motor, they are not difficult to take apart, I did one myself for similar reasons. Just make sure you take a good note and photos of the wiring connections and I'm sure you'll be ok.

Chris D

[andrewtoplis]

Thanks, I'm guessing you mean this one?

modeleng.proboards.com/thread/13955/myford-ml7-motor

I don't have an air line, but I'll try to clean it as best I can and see if it spins up again. It's odd that it was fine previously!

[coniston]

Yes Andy, that's the thread I was thinking of. A good clean with a clean brush and human blow out will I am sure help. Good luck with it.

Chris D

[andrewtoplis]

Thankfully a simple answer proved to be it....one of the motor wires had become loose in the crimp, we must have nudged it when we moved the lathe thus breaking the circuit. I'm heartily relieved not to have to take the motor to bits! Now to finally make some swarf with it..