Member postings for Peter Sansom

Your dimensions are correct. It is an angular contact bearing NSK 7205B or equivalent. Just purchase a good quality bearing from the better bearing companies, SKF, NSK, RHP. Do not use cheap Chinese bearings as they have too much vibration.

Your other option is to do the Taper Roller bearing conversion, you will find it documented here

http://www.model-engineer.co.uk/news/article/improved-headstock-bearings-for-a-myford-super-7/24866

Again make sure you use the best quality bearings. You can either find them online or your local bearing supplier.

The pitch for .7m is .0278" and for 36TPI .0276", a difference of .0.78%. Cut which ever you have the change gears for.

Could be 36tpi, if you have a QC Gearbox that is a standard thread and more likely to be used in the 6 years that this initial style of headstock was built. The thimble is an odd size as 21.9mm OD, so could be 22mm. What is the bore in the headstock for the oil thimble?

Remember that the Idea is not to fill the sight glass, but rather to have a steady drip of a good quality Hydraulic oil. Myford recommend ISO 32, but I have always run ISO 46 as it as felt to be better in warmer areas such as Australia. Also at the time easy access to that oil as where I was working used large quantities for steam turbine lubrication.

I would not remove the Oiler tube. Had a look at my lathe and the tube is tight. I have a drawing that shows it has 2 different diameters, but without a photo cannot say accurately. If you made a new insert, referred to a a thimble with a slot in the back the shape and size of the oil nozzle. When I looked at the thimble on my lathe it is not tight and the hole in the top is much larger than the nozzle thimble.

An alternative option would be to leave the thimble out, machine a piece of tube to hold a sight glass cover and loctite it to the housing. The white Plastic makes it easier to see the oil, that is all.

I have just finished the Taper Roller bearing conversion. If you are doing the conversion look for good quality bearings, SKF, NSK, RHP etc. Do not use cheap bearings, there are differences. Also watch the recess machined in the retainers, for SKF bearings the bore had to be 48.5mm or it rubbed on the bearing cage. The original spacer was used.

The Myford shim packs are comprised of 0.002" shims. you should be able to close the gap to less than 0.002". This is assuming that the bed has an even thickness and carriage does not jam as you get closer to the tailstock. Normal practice is to remove the headstock put the bed upside down in a surface grinder, and grind the bottom of the feet. the bed is then turned up the right way and the top is ground including the headstock end. The biggest issue is finding a surface grinder with enough travel.

From the grind marks on the bed under headstock, the bed was ground on a vertical spindle surface grinder similar to the Churchill Snow grinder.

The way to check the bed is to strip the bed including the headstock. If you have a good long straight edge, I used a 900mm Moore & Wright, Look for wear with feeler gauges under the first 150mm of carriage travel, particularly front shear. I can send you the wear pattern I found.

Had the bed ground on a surface grinder about 40Km from where I live. Think it cost me $80Au about a year ago. Cost more to get the saddle machined for conversion, $120Au, from another shop.

While the bed bed is probably not perfect, it is a lot better than before the regrind.

The photos show the colours. I know it needs general painting. The Super 7 on the Headstock Belt cover was also picked out in cream, but all that paint has flaked off.

I have had the lathe for since 89 and it came out of an industrial environment. So I assume that it has never been painted, particularly as the grey is in a terrible state, flaking off the belt guards etc. The year of manufacture was confirmed by the then Australian agent who contacted Myford. In addition the Serial number is a about 120 higher than the S/N of where the cone clutch was introduced. Will add a picture in the morning.

I have a 1958 Super 7, sight glass headstock, cone clutch. The inside of the bed and lettering is a cream colour.

For Linux, just use a Web Browser. I use either Firefox or Chromium/Chrome on Debian.

How deep a bore? You can get various electric bore pumps that will fit into a 4" bore.

The actual part that broke is the backplate for the change gear cover on a 1958 Super 7B. It had a crack in the hinge area which had a piece of steel attached by 2 screws to reinforce the area where there was a crack when I acquired the lathe almost 30 years ago.

Was putting the lathe back together after a bed grind and some other work when it broke through. I was rushing as the lathe was in pieces and we are moving house soon, needed to be back together for the move of about 1800Km sometime in the next few months.

Peter

I have the teflon liner fro the MIG torch, .9mm 5356 Aluminium MIG wire and oversize tips for .9mm.

Just need to get some time over the weekend, but I will photograph.

Have been cleaning the aluminium in preparation to weld. The intention is to tack it first then fill in the gaps between the tacks. I have been advised to preheat the casting first.

Peter

I will try welding next week. A local welding supplier has a teflon liner and a small roll of aluminium mig wire. Will be down that way on Tuesday.

Will Mig weld the crack.

Peter

Does anyone know what the material that belt and change gear covers on a Super 7 are cast out of.

Is it Aluminium or is it Zinc based material such as Zamak?

Has anyone tried welding the covers and was it successful.

My change gear back cover has a large crack in it from 60 years of use in hte hinge area and I am looking at repair options. The 2 options I have are

1. weld the crack..

2. Use JB Weld to glue and screw an aluminium cover plate secured by a combination of JB Weld and screws over the top to make a laminated joint.

Thanks

Peter

Oxy Acetylene is a hotter flame than Oxy Propane

About the only thing that Oxy Acetylene is necessary for is Oxy welding. You won't get a hot enough flame when using welding.

If you want to cut, braze including silver brazing then Propane is good. Propane is also more economical to use.

Thanks for the information, I have pulled the shaft out, but not had time to disassemble the clutch. Found some SKF bearings for for the clutch in Melbourne at a good price $10AU each. Locating a non Chinese thrust bearing is a problem.

Did find that the the push bar does not have the spring and ball in the end. the push bar is not machined for these items. As the lathe S/N indicates it was probably fitted with one of the initial batches of the cone clutch and that was applied at a later stage.

Peter

The issue is not on the 4 step pulley but between the Twin Vee Pulley (112), the abutment washer (98) and the step from 5/8" to 7/8" on the countershaft.

Perhaps the circlip on the left side of the counter shaft is missing. This is the one part of the lathe that I have not had a reason to disassemble, perhaps it is time now.

Peter

I have a Super 7 with a Mk2 clutch manufactured just after the change in design.

I have just reassembled the lathe after doing some reconditioning of it and noticed a noise in the clutch assembly, worse when the clutch is disengaged.

After studying the problem I noticed that there is approximately 1mm of movement of the pulley asembly on the counter shaft. The gap is between the abutment washer and shaft shoulder.

Is this normal or not?

Peter

I have an identical S7 manufactured in 1958, SK8233, one of teh first with the new clutch. Currently in pieces having had the bed ground as a 60th birthday. Just trying to get the carriage machined to convert to a wide bed as per George Thomas.

Your paint is in much better condition, mine is cracked and peeling from the climate.

Enjoy it, but look for wear in the bed and teh carriage.

Peter

I have just had a 1958 Super 7 bed reground in northern Brisbane, Australia, cost me $80. Still in pieces as I need to take it to the Gold Coast where I can get access to a large surface plate (2mx1m) and Biax scraper.

will also do the wide bed conversion and Taper roller bearings on the headstock.

AS the Myford is a Flat bed, a solid surface grinder capable of grinding larger than the bed length should do a reasonable job. A vertical spindle such as a Churchill Sno grinder would be excellent, fofm the grind marks on mine under the headstock that is what it was ground with originally. Assuming it was not reground before I acquired the lathe in 89.

A 3 phase surface grinder is better as the motor speed is more constant. Have been told single phase surface grinders will not be as even.

Peter