Member postings for Martin Connelly

I don't have a Myford but I do know that what looks like a greasing point might be an oiling point. Do not apply grease unless you know for certain it is a greasing point.

Martin C

Electrolytic corrosion requires an electrolyte. Water with salt in it can act as an electrolyte, salt free water is a very poor electrolyte and salt absorbs atmospheric moisture as well. Not a good idea to have even a very small amount of salt water on ferrous metals. If the majority of water evaporates the salt is left behind. I have seen problems with steel and stainless steel corroding because a hot water bath used to clean off dye penetrant products and flash dry the part was filled with tap water instead of demineralised water.

Martin C

The usual reason given for not recommending using washing up liquid for car washing or windscreen washer fluid is that it contains salt. Probably not a good idea to use it on machines if it does. The reason I use rain water is to avoid hard water salts so I would never put washing up liquid, even if very dilute, on my machines without being sure it was salt free.

Martin C

Soluble oils are not really soluble, they just have an added surfactant. This helps the process of the oil breaking into small droplets and reduces water surface tension to keep the small droplets in suspension and so form an emulsion. It is possible the surfactant had been damaged by frost but I don't know. All the soluble oils I have used I just put the correct volume into a hand sprayer then added the water (rain water from a water butt to avoid any hard water salts) followed by a quick shake, with the top on, to mix the two.

I would just assume it is no good and replace it with something you know is really a cutting oil that has not been frost damaged, it goes a long way when diluted down with water so the cost is not too bad.

Martin C

This is a taper reamer, size is 1/8" so it is 1:48 taper with the 1/8" being the larger end. The cutting length is about 2" so you can work out that the other end goes down to about 3/32". The pin is a 3/16" pin and goes from 3/16" to 1/8" so they do not match, I would need a smaller pin or a larger reamer depending on what I was going to be doing. The larger pin suits the existing taper pin holes on my lathe which is why I have it, the reamer was just the first one I picked up but thought the differences in sizes was important to point out. Not all taper reamers fit all pins, they have to be sized to each other. I hope this answers your question regarding where they can be used.

Martin C

The taper pins lock in the same way a Morse taper does. They do not need a lot of hammering to put them in place or to remove them but they stay in place under normal circumstances. I think the imperial taper is 1:48 and the metric equivalent is 1:50. You need a taper reamer to suit your preference and you can buy tapered pins to cut to size. There are plenty of examples of machine tools with handles held in position by taper pins.

Martin C

Jason typed faster than me

Edited By Martin Connelly on 05/07/2023 20:32:18

Anything that can be done to stiffen the process will help so if all the none moving axes are locked and the stick out of both the spindle in the head and the tool in the collet is reduced to the minimum then the next question is are you tightening the tool in the collet sufficiently to reduce flex. If you are not using a ball bearing ER nut and suitable wrenches to put high torque on the nut and therefore high pressure on the tool shank then the tool position may flex slightly in the collet holder.

Martin C

A "radio controlled" clock would self correct daily including correcting for summer time and GMT changing (unless your workshop is a Faraday cage). Available in digital and analogue formats. I picked up a couple of low cost radio controlled alarm clocks from Lidl a few years back and the batteries last for many years.

Martin C

I see from one of your pictures from 21 June that you have a 4 pin ER nut wrench. I cannot tell from your photos if the nut is one with a bearing or not. If you have milling cutters in an ER collet being pulled out there are a number of things that I would recommend, one is the 4 pin wrench which you have, another is a collet nut with an internal bearing and a third is that the inside taper of the collet chuck should be clean but with a fine smear of oil to allow the collet to close up easily. The tool shank and bore of the collets should be oil free and the collet slots clear of debris. The recommended torque for ER nuts is quite high and the best way to achieve this is with the bearing nut tightened with the 4 pin wrench and a correctly sized single ended wrench to suit the flats on the collet chuck. If you have a collet chuck without flats (there are some about) then spin up the grinder and put some on it. I, and I expect many people, have never had a milling cutter pull out of an ER chuck when using it following these recommendations.

Martin C

The knocking at the top of the shaft may be clearance play between the male and female splines of the drive.

Martin C

My father-in-law's body went to Nottingham Queens University Teaching Hospital. We had a funeral service without a coffin/body. I think it was about 10 years later when they informed us that his remains had been completely disposed of. I think I may do the same thing.

Martin C

We had one of those Prior auto indexing punches for the labels on Rosemount pressure transmitters. It was easier to put the label in a small CNC engraver than to get a consistently good result with it.

Martin C

Do you have a local shop that does shoe repairs, key cutting and dog tag engraving? If they have a modern CNC dot peening or engraving machine (or similar) it will probably have the software for sequential numbering included in the package. The old style Taylor Hobson pantograph engravers are gradually being replaced by small desktop CNC machines.

I worked in an ISO9001 accredited factory. ISO9001 meant we had (for example) quality control, a system of written standards, good standards of record keeping, material certification, and working practices and that people worked to those written procedures. We used dot peening to mark the necessary part numbers and traceability numbers on pipes. The need for the part marking was due to working to ISO9001 but manual etching could have been used if it was a well controlled system that met the requirements laid out in the quality marking standard we worked to and was specified on the part's drawing. As far as pipes were concerned if stamping was to be used it was limited to pipes with wall thicknesses that could stand up to the process or had flanges that could be stamped on the rim, 16swg (1.6mm) tube could never be stamped with hammer stamps.

Martin C

I have an aluminium tap of the thread forming type. I don't recall seeing the equivalent thread forming die for aluminium. The point is that the thread forming tap does not cut, it pushes the aluminium into the correct thread form to form the thread profile, as cutting threads in low alloyed aluminium with a tap can result in poor thread forms and low strength threads. Tri-lobe thread forming screws work using a similar process but can be used on steel. I imagine most external threads in aluminium of mass produced parts are rolled rather than cut. It is a common process used for the majority of fasteners that are available off the shelf. The concave ends visible on many machine screws is an obvious result of this process.

I think I have seen thread rolling boxes for use in lathe tailstocks but it is a bit of a specialised need and you would have to be making a lot of parts to justify the cost of buying one.

Martin C

Should have said a tap for aluminium at the beginning. What I put makes it sound like the tap is made of aluminium.

Edited By Martin Connelly on 28/06/2023 11:08:22

If you think about it a 5A cartridge fuse will blow by melting at a lot less than 16A and if it was not inside a ceramic tube there would probably be a flash and a bang. This means a short from mains to earth caused by a fine ribbon of swarf can trip the RCD which only requires a small current to trip it but the 16A fuse may not blow. There will probably be some evidence somewhere of the short and, as pointed out above, it may be hidden in odd corners or places you have not thought about checking.

I imagine the short was to the earthed metalwork of the lathe so I would think in this case the earth connection has worked the way it is supposed to.

Martin C

I have turned HSS with CCGT inserts.

Martin C

Agree with Kiwi Bloke, drill into the end of the leadscrew, tap it and Loctite in a stud of the correct length and thread. My bet would be that if there is any hardening it is only on the surface, not through to the core.

Martin C

Edited By Martin Connelly on 27/06/2023 10:09:10

If you go to the recent thread on identifying collets and follow the link to the old Crawford Collets pages they show the accuracy figure is TIR. The new CC catalogue also shows accuracy as TIR.

Martin C

I have to object to the idea that something from the 60s is vintage

Martin C

I have also seen a socket where a central heating pipe had been routed below it causing issues with some moulded on plugs with a stiff cable strain relief being part of the moulding.

Martin C