Member postings for Mike Crossfield

Bill,

I used 2ba steel countersunk screws to attach the extruded aluminium mDRO scale holders to my D-W. These screws are directly beneath the self adhesive scale strips. I went through a careful calibration process, and I saw no problems due to the screws. There were small linear errors on both axes, but these could be adjusted out in the system software. As you have found, the large clunky brackets supplied with the kit are useless for use with the D-W, which was why I made my own. As well as using slotted holes in the brackets I used jacking grub screws so that I could finely adjust the read head positions in 3 dimensions. The read heads and the scales are electrically in direct contact with the mill, which is well earthed, and I have had no problems with erratic readings.

Mike

Hi Bill

I fitted a Machine-DRO system with magnetic scales to my Mk1 D-W a couple or three years ago. On the y-axis l mounted the scale on length of aluminium angle attached to the underside of the carriage, and I mounted the read head on a shop-made adjustable bracket bolted to the base casting. There are a couple of photos in my album which show the x and y scale mountings. If, like me, you want to mount the y axis scale behind the table, you will need to design the mountings very carefully to avoid losing x axis travel. It can be done though!

Regards

Mike

+1 for Tractol. High pigment content so covers well, and tough as old boots. Good for brushing because it dries slowly, which means there is no problem keeping a wet edge, and brush marks tend to flow out leaving a very good finish. Need to be careful to avoid dust though. When fully cured it can be cut back and polished to a very high gloss. Smith and Allen keep a wide range of colours, and I think they also supply it in spray cans.

Hollowpoint

I can recommend the Tome Feteira Swiss pattern needle files sold by Arceurotrade. IMHO close to Vallorbe quality, but at a more acceptable price. Set of 6 was about £38 pounds last time I looked, though I prefer to buy just the shapes and cuts I need.

Mike

Lynne

Rather baffled by your comments. What was the problem viewing the pictures in my album?

Also don't understand the reference to Arc. As far I am aware Arc don't sell magnetic DROs.

Magnetic scales and read heads are more compact than optical equivalents, and therefore easier to install if space is tight. I used M-DRO magnetic scales for the install on my Dore Westbury mill, and they fitted in quite nicely after I designed my own mounting brackets. There are some photos in my album.

Mike

Matt,

by remarkable coincidence someone called Shaun has just posted an identical request on the Myford-lathes group on groups.io. A responder has posted drawing of the trunions in the files section Join the group and get the info you need!

hth

Mike

Ian

you could try speaking to Pantograph Services. www.pantograph.co.uk . They were very helpful to me when I needed assistance with my Taylor Hobson engraver. Even if they don’t have what you need, they may know someone who can help.

mMike

A very interesting thread which is very timely for me. The alloy wheels on my wife's car willl need renovating soon, and I have been advised that powder coating will be much tougher than paint in this challenging application. A number of local wheel refurbishment specialists companies offer it, and it is more expensive than paint.

Is it all a con then?

Jeremy

Since no-one has answered your specific question about the benefits of the lead screw clutch I thought I'd chip in.

The handle on the saddle which moves the saddle along the bed is quite highly geared. It's fine for making coarse movements of the saddle, but not very good if you want to manually fine-feed the saddle to make delicate cuts. The solution is to engage the half-nuts, and move the saddle using the handle on the end of the lead screw. The fly in the ointment is that if the change wheels have been set up to provide self-feed or cut screw threads, the lead screw will be constantly rotating. Even if you disengage the gearing, which is inconvenient, then depending on how you do it, it may still be difficult to turn the handle because you may be trying to drive part of he gear train backwards. With the lead screw clutch you can instantly disengage the lead screw from the change wheels and overcome the problem.

HTH

Mike

I’ve always found that white spirit is the best common solvent for cleaning up old machinery. Helps to let it soak in well before scrubbing off. Old tooth brush is a good tool for this job.

+1 For Elbow Grease. A good general purpose water-based degreaser in a spray bottle, and cheap as chips. I used to stock up on it every time I went North to visit my old Mum in Lancashire, but since her demise I despaired of finding it in my adopted South. However I was delighted to find recently that my local Range stocks it. £1 a bottle.

When I bought my early Super 7 twenty-odd years ago the bed was well worn, but it came with the remains of an ML7 capstan lathe. The bed on this was unworn (since it just served as the base for the capstan assembly). I believe the ML7 capstan lathe used a standard ML7 bed. I rebuilt the Super 7 using this bed, and it has served me very well ever since. If you want to go down this route, I.e. a Super 7 headstock on an ML7 bed, bear in mind that you will need not just the bare headstock but also the complete countershaft assembly, motor and double pulley, motor bracket, tumbler and change gears, banjo, covers and back plates etc. There might also be an issue with interfacing with the leadscrew, which may be a different diameter to that used on the Super7. If you have all these parts it’s pretty straightforward. Aside from checking tailstock height as has already been mentioned, the only other issues I remember were that the countershaft arm required a new fixing hole drilling and tapping in the back of the bed, and the mounting holes for the saddle rack were in the wrong places, and needed redrilling and tapping. This latter point may be related to the age of my Super 7 and/or the fact that the bed came from a capstan lathe.

Hope this helps

Mike

Andy

The advertised book is still for sale as of 11.00 today, but I cannot contact you because your message does not include an email address or other contact details. Please reply with your details if you are still interested.

Despite the name of his website, Ian Cobb supplies a range of different brass, not just engraving brass.

Mike

John,

Try Ian T Cobb at www.clockmaking-brass.co.uk. He stocks a wide range and will cut to pretty much any size.

Mike

I’ve bought ER25 collets a couple of times from CTC and been very happy with the quality and price. The chap running the operation in China, a German, was very helpful when I had some queries and wanted a special size. In my experience, accuracy doesn’t seems to be far from the stated 0.4 thou runout with everything carefully cleaned.

Mike

Ken

I make all the wheels (and pinions for that matter) for my clocks using home-made cutters. I use a variation of the “button” method to make the cutters. I start out with a cutter in the form of a parting tool ground to an accurate width with a semicircular tip. I use this to cut the wheel/pinion cutter from round silver steel. The centre fixing hole is offset to create cutting clearance. After parting off, a segment of the disc is removed to create the cutting edge, and the cutter is hardened and tempered. Then away you go. Brass wheels are easy to cut in a single pass with the mill running flat out (2000 rpm). Steel pinions are harder, and I typically take 3 or 4 passes running at 200rpm, and using lots of cutting oil. I get all my cutter geometry data from the very useful table in the Meadows and Passmore catalogue

Examples of a wheel cutter, a pinion cutter, and some wheels and pinions cut for my latest clock are shown below.

I have a strip of the damp proof plastic membrane that bricklayers use fixed to the bottom inside face of my up and over garage doors. I used self tappers and washers to fix. Very flexible, weather-proof and cheap as chips. Works a treat for keeping out wind blown rain and leaves.

Mike

I dowelled the saddle gib on my early Super 7 about 20 years ago after reading an item by either GHT or Jack Redford. It was certainly an improvement, and allowed the gib to be set very closely without tightening up when the saddle was moved. Interestingly, Myford changed the gib design on later models so that one of the screws provided the equivalent of a dowel function. However I don’t believe this was carried across to the ML7.

Mike

20-odd years ago I made George Thomas’ centre height gauge. Very nice design which can be used from the bed or the top of the cross slide. I use it all the time and can highly recommend it.