Member postings for not done it yet

I've come accros similar, in junk boxes of items at sales, so prolly quite common. I have no idea of actual use, but agricultural sales were the ones I usually frequented.

How can this be down to the presence or not of an unloader valve?

'Presence or not' or not working properly?

The very simple check/test of seeing if it works from zero pressure, immediately after showing signs of stalling, will indicate whether the motor is actually restarting correctly after a high pressure restart.

Very simple, easy to do and informative. The job needs analysing as to whether the problem is due to the motor not fully speeding or the compressor tightening up.

The motor is well oversized for the job. My 10cfm,   @10 Bar, compressor has a 2HP motor, but only 1425rpm (so better starting characteristics)

Guessing is no good at all. Actual checking , to isolate the problem, is the first priority!.

Edited By not done it yet on 27/08/2016 07:21:05

The Americans have been using metric bearings for years, just requoted as imperial. Not sure if all bearings, but likely most.

I can instantly envisage what 3/8” looks like - but 9.525mm? - I’ll get m’book then !

The simple argument to this is that any metricated person woud never even think of what the imperial fraction would be for 10mm! Even if they came accross a 9.525mm measurement and converted it to inches, they would come up with a decimal answer of 0.375, not 3/8.

Come to think about it, who would dial in 3/8 on an imperial lathe without first convertig it to thousandths? Try 25/32 or 31/64 and see what I mean? So only decimal inches are really used on the lathe or milling machine, anyway.

I have both metric and imperial machines (not my lathe). Metric is favourite by far (although I am completely competent in both), but it is virtually immaterial with a dro, excepting threading as stated above.

I have used most of the different systems over the last half century, or more, and metric is very much universal (SI uits, actually).The only difference for threading is needing a conversion gear, or gears, and the cutter must be driven in reverse ready for the next cut.

Only the US uses feet and inches system as a major nation. All imperial units can be changed to metric units, but for modellers making scale models in 1:2, 1:4, and a few other scales, it might appear to be easier to scale original full sized imperial drawings.

The imperial system will be used less and less as time progresses. That is for sure! Think globally, and realise that most cars made have metric speedometers, not mph ones! Only the US distorts the otherwise almost universal metric system.

Imperial fixings and tooling will become more expensive as time progresses. Metric is already the manufacturer's choice and will be almost universal if (or when) the US were to join the rest of the world in this century.

Most, who advocate imperial, will be older or american. Many british children still only know their height and weght in imperial units - but lots don't know how many inches there are in a foot, or pounds in a stone!

Yes, be brave, go metric. I only bought imperial machines because, for me, old british iron is preferable to lesser quality chinese items.

Don't try to complicate things. You do not need an infrared thermometer. Just check as I said earlier. A rev counter would be more appropriate.

Curtain rail if around a 25mm diameter pipe? Any other sugestions?

Know little about Myfords (I've got a Raglan) but I doubt it had a V belt drive originally. More likel

y a flat belt, I would guess, but I may be wrong.

Cupro-nickel pipe is your typical quality replacement brake pipe for cars and trucks, so fairly high pressure and corrosion resistant. No idea what else it might be used for. Max inch and a quarter, if it was imperial when new. I was wondering how each 'bed length' gets fed in without excess knurling in one place (or maybe it doesn't matter?).

Does the motor actually get to full speed on restart? If not it may be starting on load due to back leakage and then struggling because the start windings have not got it up to speed quickly enough?

Try starting from very low pressure, or zero, immediately after it gets to the stalling situation. That would determine if it is the compressor getting tight or the motor not delivering full torque.

The solder sucker is prolly best for desoldering electronics from a pcb. I don't use mine often but very useful - if I can find it! Solder wick is likely better for long runs like you have. Main difference is that the sucker will last years (if you don't lose it!).

Ray,

You have a PM.

Nowt to do with the lathe.

Take the old bearigs to your local bearing factor. They will (or should) know either the bearing or an equivalent.

My 1'' Centec does not have a keyway. Sorry for my perhaps misleading post earlier, but after hunting the net the Mk2 seemed to be fitted with a simple vertical head which clamped to the arbor support bar. Can't locate that pic since. There was me thinking it might be like my Centec, but on a much smaller scale.

There's another.

Niobium is a different element - it is not Neodymium!

I hope the one coming in the opposite direction doesn't collide.......

Beginners reading this should take careful note of this thread. Cheaper tools are not necessarily best and can stress your major investment.

Purchase decisions, for things such as the QCTP, where not paying the 'apparent better price' for a complete 'kit' and buying only what is needed, is a better option. I bought a complete set and have regretted paying more for something I will not use (hindsight, of course!). I daresay I will likely machine it into another basic tool holder eventually, but it is, nevertheless, annoying.

A 4'' with a worn down disc? Dremels are at the other end of the spectrum? How about a grinder on a flxible power drive, similar but larger than those supplied with dremels. Similar to those used that clean up and polish engine ports/heads, etc? An air tool is most likely the easiest option, if not so quiet, for your purpose?

For what purpose, btw. Might help to know?

I would be more thoughtful re the periphery runout than the spindle hole. Dti'd for true running in both axial and radial direcections, the boring will achieve the target of true running. Setting up on the bore or hub will introduce the opportunity of more error, at the outer circumference, for the same tolerance of the setting procedure.

Are they prone to killing motors.

'They' being lathes? No.

Mostly, electric motors are very reliable. Usually damaged by incorrect usage. But if it is Chinese, that generalisation may be being a bit stretched.