Member postings for old mart

Sorry, Michael, I would never have thought of looking in your album, until your subsequent mention of it.

You missed out "damping", Michael.

 As it happened, there was an easier source of the very thick grease that will not migrate into unwanted areas, the grease used for car disc brake mechanisms. it comes in little sachets and is likely to be available at a car spares shop, quicker than the post from China.

Edited By old mart on 24/11/2022 21:29:11

It won't cost anything to advertise on this forum, but try other sites at the same time, I put a lathe on here and it is still here after 3 1/2 months.

That ebay grease is rather elusive, but if "high viscosity damping grease" is searched for, there it is.

The cost of the aluminium and having it hard anodised would be more than using cast iron. If the mating part is also aluminium, then keep the joint well lubricated.

Geoff Walker's picture shows an aluminium frame, but the moving parts are steel, by the look of them.

Edited By old mart on 23/11/2022 21:24:13

One of the 3 feet square granite surface tables in our fitting shop at work was simply sitting on a bench on top of a sheet of 1/2" thick closed cell sponge rubber. It was checked every year by specialists with all the right equipment and had errors less than 5 microns in any direction which was plenty good enough for us. The tables in the inspection were very likely better.

One reason why the 12" square glass plate has not neen turned round yet is because I used about 20 of those square sticky fixers to hold it onto the wood backing. Rather hard to remove, it might need a thin wire to cut through them, or a pallette knife.

Torque is the least accurate measured method of tightening fasteners, but is unavoidable in most cases. One thing that must me adhered to is that the fastener must be torqued up the final 20% in one movement. If you stop even slightly short, possibly due to difficulties with swinging the torque wrench, the torque will not be correct. As soom as the tightening is interrupted, the subsequent torque needed to start things moving again will be much higher, this is called stiction. Backing off and re applying the torque without a pause right up to the full torque is the answer. Special requirements for stretch bolts must be adhered to exactly.

I take these wonderful claims with a pinch of salt, its a shame that some people waste money on them.

The first plate that we had at the museum, still used for some jobs, is a 12" square of thick float glass from a glass merchant. It's at least 1/2" thick and sits in a wood frame with a lid made by one of the volunteers. For small jobs, it is excellent and might be very cheap, depending on whether the glass originated from a damaged shop window, and cut to measure. It has many scratches, but could be turned over to the new side if necessary. The scratches do not affect its flatness.

I bought a low grade 2 foot square cast iron table on ebay for about £55 and together with the seller, just managed to get it into the back of my Corsa D upside down. Fortunately there were four holes through the top tapped 3/8 UNF, and when I got it to the museum the next day, a Sunday, I was able to make a couple of lifting eyes to use the engine hoist to get it out. I needed it out as it was on top of my spare wheel.

Edited By old mart on 23/11/2022 19:13:41

I have had a good look at everything and have come to the conclusion that I must have been fooled by an optical illusion, Mike agrees with that conclusion. The job has the pocket just off centre as it is a destroyed parting off tool being repurposed and after careful inspection, there is no way that the Y axis could have moved. I have taken a picture of the tool and insert which fit together very well.

I believe there are standard cast iron, SG (ductile cast iron, sometimes called semi steel) and steel chuck bodies. As already mentioned, the file test will tell if it can be drilled.

ACF50 is akin to WD40 and several others which help to stop the rust forming. As I recall, the Navy used to use WD40, but changed to a cheaper product, maybe ACF50 back in the 70's. Waxoil is similar to some types of ensis fluid but easier to obtain, very effective, but a pig to remove afterwards.

Edited By old mart on 21/11/2022 17:59:11

Far less bother and the Vevors are plenty good enough for home shop use. Judging from the size of the backplate you might have been able to fit the next size up. There is a probability that you will have to drill new holes in the backplate to line up with the new chuck threads, and possibly adjust the size of the register on the backplate. There will be plenty of room for any modifications fortunately. The numbers on the jaws are serial numbers and are of no help in identification.

Edited By old mart on 21/11/2022 17:49:13

Have a great day out, Neil, if you are taking photo's with a camera, take the widest angle lens you have. Since then they have built a big new extension to the museum. When I went there about 14 years ago, there was a Brough motorcycle leaning against a wall, I have often wondered about that. Just down the road is Winfrith Heath, the site of one of the earliest British nuclear reactors. Also, the Sammy Miller motorcycle museum is not far away.

I fully agree with Dave Halford, do not think about turning it. Years ago when fitting central heating to my bungalow, I found the main stopcock in the path didn't want to turn fully off, and I broke it off. I changed the stopcock inside the house with a trickle of water running, helped immensely by the old nut and olive fitting the new tap. The broken stopcock was 2 feet below the surface in a 4" diameter hole. The tap handle had broken at the square end of the brass shaft leaving about an inch projecting. I rushed out to a very good local tool shop and bought set of three 1/2" drive stud extractors, the type that look like a long socket with internal rollers and a 12" extension. Together with my extensions, one of the extractors fitted and turned the stopcock back on. Years later a new main was pushed through about 4 feet deep for all the houses and a brand new plastic stopcock was fitted, all without digging a trench through 120 yards of front gardens, clever, these water board guys are, I thought.

I will be checking very carefully on Wednesday, I don't remember exactly how the pivot is engineered. The shaft must have moved even though the head was only moved the 7 degrees and there is no gap between the degree scale and the cursor mark. Fortunately I noticed something was not right before scrapping the work which took about 3 hours to get secured to my satisfaction. I will report my findings.

I have found a picture of the main column without the head fitted, the rectangular block attached on the right hand side has the scribed zero line on its outer edge. There is a trace of a witness mark where the degree scale on the head support is normally in contact with the column.

Edited By old mart on 20/11/2022 19:35:59

Trying to retrofit speed control to a battery angle grinder seems a total waste of time to me. There will be a shortage of room inside the body. Shame the Lidl one was not bought, both my 12V and 20V have the speed control as standard.

Today was the first time I have ever used the Light Vertical with the head tilted. Amongst one of the job lots of inserts that I bought some time ago was a box with 8 Sandvik round turning inserts, 20mm diameter. I had a damaged 20mm parting off tool with a 6mm thread in the clamp end and it was to be modified to hold the round inserts. Sitting the tool on the rotary table with the 6mm hole centralised, a pocket was milled to match the diameter of the base of the insert, 18.42mm. I used a 16mm solid carbide end mill to mill the pocket to depth and then moved the X axis 0.576mm and rotated the table to get the base diameter. The insert sides are 7 degrees so the mill head was tilted that ammount to make the pocket fit the insert exactly. After tilting the head and setting the lowest edge of the end mill about 0.5mm above the pocket base, I noticed something strange, as if the head had moved out on the Y axis by about 1mm. The cutter was no longed centralised in the mouth of the pocket. The only way to correct this was by eye, I still do not know what had happened, the degrees on the head part of the ram were still in contact with the face with the lining up line. However, the insert fits perfectly in the socket, that was the main requirement.

If you ever needed to hold heavier work, you could easily use a much larger angle plate with screws at the top of the table base as well as at the bottom.