By continuing to use this site, you agree to our use of cookies. Find out more

Member postings for Peter Sansom

Here is a list of all the postings Peter Sansom has made in our forums. Click on a thread name to jump to the thread.

Thread: Nitrogen as an Energy Store ...
14/01/2021 11:59:56

In the late 70's early 80's I worked on a on an Oxygen plant, Air Separation Unit on a steel works. The steel making process use 750t of gaseous oxygen per day and about 300t of gaseous nitrogen. Yes some liquid Oxygen and Nitrogen was produced, stored for when demand could not be met by gas production, or sold to Linde Gas.

Liquid Nitrogen is not free, there is a cost. The bulk of the liquid Oxygen and Nitrogen after being separated products is returned to gas and in this part of the process is used to cool the incoming air. Storing higher levels of liquid causes increased liquification costs.

These plants are installed in which there is a high demand for the gaseous product, Steel works, petrochemical plants etc. Liquid is not the primary product, it is the method of separating the products. Liquid is used for long term storage and for easy transport unless you are in the rocket business.

Thread: Super 7 Lathe Clutch, Countershaft or Pulley Wobble
09/01/2021 11:38:26

The keyway, on the motor shaft and pulley and therefor the key size is dependent on the motor shaft side which is governed by the motor frame size.

For a B56 frame 3/4hp 1440 rpm motor the key is 3/16" x 3/16" on a 5/8" shaft. You can purchase a length of key steel, about 6", or packs of small keys, either work.

Check your motor shaft size and keyway size before ordering. It is most likely imperial, not metric. There used to be a smaller bore pulley available, today they list 5/8" and 16mm. Did you purchase the correct one for your motor? a 5/18" pulley will not go in a 16 mm shaft whereas teh 16mm will be a loose fit on the 5/8" shaft and will use a metric key.

The reason the key is not listed is that Myford did not supply the lathe with a motor. that was the purchasers responsibility.


Thread: GHT Rear Toolpost 8deg milling cutter
04/01/2021 11:38:46

I made the rear tool post nearly 30 years ago. From memory once I had machined the dovetail the cutter was then filed the cutter before hardening. One good thing at the time was I had access to a heat treatment shop who hardened it in a salt bath.

The cutter worked with light cuts. Saw it in the last 12 months, took a while to remember what the cutter was.

Thread: Super 7 Lathe Clutch, Countershaft or Pulley Wobble
03/01/2021 12:41:49

Check the bearings in the clutch assembly, there are 2 Deep Groove shielded ball bearings (Imperial) RLS 5-ZZ (LJ5/8-ZZ) in the clutch pulley. Replacements are available from Bearing suppliers. I replaced these bearings due to Clutch noise 2 years ago. Remove the circluips and they can be pushed out fairly easily.

Additionally there are 2 Oilit bushes and 1 ball thrust bearing (Imperial series) that the main counter shaft runs in. Can supply the SKF part number fro this bearing tomorrow as I have 1 and the new oilit bushes sitting in a Workbench drawer waiting to be replaced.

Please note there is a spring inside the clutch assembly that care must be taken to disable. Find the instructions, there are videos on youtube.


Thread: (Early) Myford Super 7 Adjusting Collar
20/11/2020 23:48:46

the Collar thread is 1/2" 26tpi.


20/11/2020 11:08:53

I will check thread on a cross slide screw in the morning. I have both metric and imperial, so one is also in storage. On Myfords web site you can get the year from the serial number.

As it is a Mk1 clutch yours was built between the start of the S7's and 1958, just prior to mine as it was built just after the clutch change, original headstock with sight glass and later clutch.


19/11/2020 11:16:54

When you say early S7, how early. I have a 1958 S7, bought a Metric Cross slide screw in the 90's and the original collar worked fine. My understanding was that only the later S7 with Power Crossfeed used a different screw.


Thread: Making storage air power out of thin air - new UK powerplant
09/11/2020 11:53:35

Sounds like the first stage of of an Air Separation Unit, also known as an Oxygen plant for Oxygen and Nitrogen.

To separate Oxygen, Nitrogen and Argon from the air the first stage is is to liquify the air. This is done by compressing the with usually a large turbo compressor, removing all water, cooling with regenerative cooling then expansion. In large scale plants that separate Oxygen and Nitrogen they are usually producing large quantities of Oxygen and Nitrogen as a gas and after putting the liquid air in a distillation column, the separated products are used for the regenerative cooling. Only small quantities of Liquid Oxygen and Nitrogen are produced.

I cannot see a Liquid Air storage plant having a high enough efficiency to be commercially viable.

Thread: For the latest in PC fashion! (Anyone here with a Master's Degree?)
28/10/2020 10:29:25

Master an slave is commonly used in IT. Glad I am getting closer to retirement. Yes I have a Masters Degree.


Thread: Help requested wiring VFD - Again!
07/10/2020 09:40:38

Thanks Dave, I am just looking at the parts for the pendant control and need to purchase a 3 phase motor.


07/10/2020 08:37:20

Yes, I have the manual, just poor printing and my eyesight and poor printing of the manual.


07/10/2020 08:10:15

I bought a VFD several weeks ago from the local branch of the well known auction house. Turned out to be the A2 VFD when it arrived. Post is very slow here at the moment.

My question is, what is the value of the external potentiometer.I find the value hard to read in the manual, is ,1 1.5k ohm or 1-5k ohm. What value are you using?



Thread: Myford Mod
08/08/2020 08:42:34

I like the idea of the timing belt as it uses the standard leadscrew. Bought a Hemmingway kit years ago, but never built it due to other life issues and I had converted the lathe to metric, which meant making a 2mm pitch LH screw. This method removes that issue. Have both imperial and metric screws, the lathe is currrently set to imperial.

What size timing belt and pulleys did you use?



Thread: 33mm Spanner
26/07/2020 13:22:47

Try 1 5/16" af, I used to use 3/4" Whitworth for the tow ball nut, which is actually 1 5/16" af in Australia.

Thread: The 2038 computer bug
13/07/2020 14:10:10

This has long been know. I remember reading about it in the 1990's. The issue is caused by the Unix operating system calculating time by using the number of seconds since the the first Unix computer was turned on in 1970. It can be mitigated my the OS kernel correct the clock when the 32bit time integer rolls over. Remember that we started with 8bit computers, then 16bit. 32bit only came in the windows world wit the 80386.

How many of you have a 80286 or older 8086, so don't worry about.

If you are worried about this remember there is a calendar correction due in about 2000 years time, extra day if I remember, read it many years ago.

That is someone elses problem, if humans are still here.

Thread: stuck chuck again
05/06/2020 12:32:48

Remive the locking pin for the chuck. then you can have a look through the pin hole. Use a piece of wire, welding rod etc, to feel the hole in the pulley. You should be able to see how far the wire goes in the hole.

If tehre is nothing jammed in the pullley hole use a bolt that is smaller than the locking pin to lock the pulley.

Never use a chuck key to remove the chuck and NEVER hit the chuck key. I use a strap wrench which will not damage the chuck. The strap wrench I have uses 25mm webbing. I had to put a longer lenght of webbing in to go around the 6" chuck


Thread: Braze Welding Gear Tooth Repair
01/06/2020 11:45:25

To Bronze braze you need either Oxy acetylene or Oxy LP gas. The LP Gas of any form without Oxy are good for silver brazing. Acetyle is required to Oxy weld.

Back in the early 70's that was what we were taught by the boiler making apprentice instructors. Where i was working at the time, repairing gears by bronze brazing to repair broken cast iron gears was regulary performed.


Thread: Die grinder or dremel - relieving cast iron
12/05/2020 11:32:41

Use a die grinder with a HSS burr. I have both a dremel and an compressed air die grinder. I had to remove some iron on the cast iron on the counter shaft support of a 1958 mk2 S7 to allow a link belt to be used. You can pick up cheap burrs online with either 6mm or 1/4" shank to suit your die grinder.


Thread: Myford Mk1 Super 7 restoration
11/05/2020 11:52:00

I have a Mk2 1958 S7. Did a recondition a couple of years ago. Still have a few bits to do and it missed out o a repaint as we were getting ready to move. Ahave been too busy after the the move to do much.

I had the bed reground. The hardest issue was finding a surface grinder long enough. ground the bed top and tehn converted the saddle to a wide bed. Also fitted taper roller bearings instead of the Angular Contact bearings. If you do the taper roller bearing conversion, make sure that you get bears from SKF, NSK or similar. The Taper Roller bearings are common as thehy are used on a lot of cars. Most are rubbish with too much noise/vibration. SKF have a higher speed rating.

Ended also replacing the bearing in he clutch as there was a lot of noise there. Still habe to replace the Clutch Thrust bearing and the Oilit bushes. I have the parts now, just need time.


Thread: wide guide conversion
11/04/2020 14:26:29

I futted teh gause plate a just over a year a go. No issues with the lead screw alignment


Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Latest Forum Posts
Support Our Partners
Eccentric July 5 2018
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest