Member postings for old mart

Clive Foster covers all the requirements. I also recommend the Inverter Drive Supermarket, for both the motor and the VFD. Have a look at the VFD'S in the same power range as the motor that you choose and find one which includes a printable pdf of their "quick start guide". That guide is worth its weight in gold if you intend to do the wiring yourself. One thing to know that if the existing motor is old, it may not have an exact match for the mounts, and the spindle diameter might not match the motor pulley. You loose power when running slower, half frequency, 25Hz will halve the power, but most motors will run at full power up to double their rated speed. Running between 25 and 100Hz will give you a 4:1 speed range which is pretty good, but you will still benefit from mechanical speed changes.

That Seig SX1LP mill recommended by SOD looks exactly right fot the type of work you are doing. The link to ARC Euro's site shows the space required for the mill which is also very important.

A Clangers man is just a youngster.

I don't think the OP is worried about getting the bearing off, its the key, which will have to be removed before a new bearing is fitted.

Many suppliers are willing to sell small quantities to the public, at a price reflecting the paperwork, handling and postage. It is worth trying contacting them to find out.

Spaulding Fasteners is a mame that just came into my mind.

Try Googling it, I got some hits, this was the first:

**LINK**

This was the key fitted in the new three phase motor for the Tom Senior light vertical. The pulley had to be bored to a larger size and there was not enough wall thickness to add a keyway. So I removed the new key from the motor shaft and milled it down flush and put 2 locking grubscrews in the pulley, adding the location bores in the key for good measure. The little screwhole is a 6BA to jack out the key if required. Any size of screw would be able to jack out the key, and do not worry if the end of the drill just touches the spindle. The jacking screw would have to have the first couple of threads removed, as the tap will not reach the bottom of the key, having a plug (bottoming) tap would come in handy here. Your key will be a straight one as the spindle is hollow.

Try Rob's milling vise method first.

Edited By old mart on 14/01/2022 12:28:20

Edited By old mart on 14/01/2022 12:31:22

Would it be possible to highlight the figures stamped or engraved on the brass parts?

Does anything show through the large holes when that disc is turned?

Edited By old mart on 11/01/2022 21:41:45

As I was thinking in terms of threading 2.5mm pitch, and using the lowest back gear speed, 39rpm, and also cutting left and right hand threads, the power reverse is tempting. The motor runs at 1440rpm and I would definitely have to try some dummy runs first. The danger of the chuck unscrewing is not present, as I can lock any size chuck, 3 or 4 jaw. I was hoping to get feedback from somebody who has regularly used a three phase instant reverse without causing damage. Andrew, your post is very reassuring.

Edited By old mart on 11/01/2022 19:38:20

I hope you are right about eventually delivering. I have two items with tracking numbers from Royal Mail which say "despatched" which are a little overdue. I cannot find out more details, only the senders can do that. One was sent on the 22 December.

I would also like to have sheilding on a machine when using a 1.6W laser, let alone a 10W one. There could be a momentary reflection of the beam when starting a cut which could be in any direction.

Another factor to think about is that the tank must never be filled right up, the liquid needs some gas volume to allow for changes of temperature.

Fantastic!

Now you need to find or make a glass cast to keep the dust of of it.

The 4.5" chuck is a rare bird, indeed, you would be best advised to look for a replacement, new or good used in 5" or 125mm. Unfortunately your backplate would also need replacing as the fixing holes would be too far outboard when fitting larger chucks. A 4" or 100mm chuck would fit the backplate with a little adjustment to the register diameter and a set of suitable holes or threaded holes put in the backplate spaced 60 degrees fron the old ones.

ARC will have 125mm chucks and may also have a Boxford backplate as well.

 Welcome to the forum, by the way.

Edited By old mart on 10/01/2022 20:56:50

I was worried because of the machines age mostly, as the manual states that it can be done when metric threading using the back gear, so as to keep the leadscrew nuts engaged, but not at high speeds. Then it goes on to say that the lever switch can be used to slow the spindle quickly from high speeds, no doubt with the intention of switching to off as the spindle stops, and with a screwed on chuck, to boot.

The Smart & Brown model A lathe has a 1 1/2 hp three phase motor and in addition to the on off buttons it has a lever switch with forward-stop-reverse. What I want to know is whether throwing the reversing lever from one direction to the other without stopping the motor will be advisable. The lathe is over 70 years old and I have never tried this before and don't want to do any damage.

The whole thread production will be straightforward using singlepoint on the lathe. Because the thread is fine pitch, I can use an IR16 insert on a 16mm bar which gives plenty of clearance, unlike the 5ACME with an IR22 insert which required a custom made bar. The thread diameter is also unusual, being about 22.8mm, try finding a tap for that.

How many people know that you must give way to a bus when the driver switches their right hand indicator on at a bus stop.

That so reminds me of the Andre Previn sketch on the Morecambe and Wise show.

I have found that 2.5mm pitch trapezoidal is not included on the charts, but helpfully, the calculations are very similar to ACME. The nominal thread depth is half the pitch. Better still, having changed all the change gears to MOD1 for lack of original gears for the Smart & Brown model A, I started off getting a 125/127 and it is all that is needed for producing the 2.5mm pitch. If 1/10" pitch is set and the 125 is driven and the 127 is output, the result pitch will be 0.0984251", equivalent to 2.4999975mm, close enough for government work.

Another bad design is the fixing of the Xaxis nut. When you remove the bed, an easy job, you have the choice of removing the whole Y axis casting together with the X axis leadscrew or unscrewing the leadscrew first from the nut, about 180 turns. This is because the nut is attached from underneath the Y axis casting. That will be remedied.