Member postings for old mart

We used Lee plugs in aluminium brake manifolds and shimmy damper units for aircraft which tested at 3500 psi. The finish in the holes was significantly better than a drilled hole, but tiny leaks in something like the op's crankshaft would not matter at all. Also Lee plugs require a stepped hole, or pressing in the expansion plug would just push the hollow part down the hole, so they will not be suitable.

Scanning ebay, as I do regularly, I came across this advert for tool cabinets. They are Versatool with several swing out trays. We have two of their products at the museum, both on wheels, with two drawers and two swing out trays. The quality is superb, and I wish I could afford them. For anyone looking for this sort of storage located in West Sussex, they are well worth a look:

**LINK**

If you go on the Mitutoyo website, they sell spares, but you need to register before getting the full information. I bought part of the electronics of a digital mike from them about 7 years ago, with great success. Check the voltage of the battery, it should be 1.5V.

Not having the dimensions of the Atlas or Boxford is not a disaster for me as the lathe itself is available for measuring. The difficulty is gauging the thread angle. I would think the two makes are not compatible.

The prices of backplates from the USA is cheap, until the postage is added, which quadruples the price.

I already have the blank casting which is about 167mm diameter.

I would guess that those threads were produced on a rotary shaper, if such a tool ever existed.

I will be making an Atlas chuck backplate in the near future, and wondered if the threads are 60, or 55 degree. If they are 60 degree, I will have to buy a carbide insert, as the ones I have for Smart & Brown are Whitworth form.

It would be so much easier to do any insulation in the shed before there is anything in it.

I last used a Burnerd lever collet in a Myford Super Seven 45 years ago, which should work in a similar way. The object of the mechanism is the speed of use, so when the closer is set for a little slack, then operating the lever should clamp the work, or release using only the lever. This should work if all the workpieces are the same od.

Edited By old mart on 20/09/2019 14:35:48

That cnc engraving is superb, professional quality. If the dial is steel, it might be possible to get a small pot of gun blue/black and then rub back the rest of the surface with some 800 wet and dry with oil. it would have to be extremely clean before blueing.

We have a float glass plate of about 1 foot square on a chipboard base with some 1/4 square beading around the edge and its own lid at the museum, which is really useful. I recently got hold of a 2 foot square cast iron plate which is really good for the extra size, but we have room for it, and the glass one would be a good size for most model makers, and flat enough for 98% of work. The glass one has the advantage of being light enough to move out of the way if you have little room available.

8mm metric fine is 1mm pitch. The measured od is pretty much what would be expected from an 8mm shaft. I presume it is part of the Toyota motor which is unlikely to have anything other than metric threads.

Make sure you get split dies and the correct diestock for them.

I believe Arc do serial taps in sets of three.

In the legacy left to the museum, was a box of metric taps and drills with the Parkside logo, which is from Lidl. I tried out a couple and they were better than expected.

Surface plates usually have straight sides to allow easy use of a surface gauge. As for squareness, I cannot be dead sure, but its likely they are within a milling machines tolerances.

You said it would be ideal for a conversion, and without pictures to prove that, how are we able to comment?

He spoiled it for me when he held the hammer by the head end. It might have been because he knew the head was about to come off. And the cutting torch and sunglasses.

I use spotting drills on the mill and centre drills on the lathe, where the 60 degree matches live and dead centres. I also have some centre drills with a 90 rather than 60 degree angle, I'm not sure what they are intended for, but I use them for subsequent drilling.

It pays to use a new drill bit if the hole is critical, a good make if possible.

If you make a stronger mix than normal, it will take longer before it starts to rot and stink the place out.

 Having the bed at a slight angle won't make any difference to it, lathes on ships work perfectly well. The word "levelling" is a misnomer, as already mentioned more than once.

Edited By old mart on 16/09/2019 20:46:29

Well, the UK version appears to be assembled, and the Chinese one is a bag of parts, how can that be a rip off?

Ductile cast iron, unless you already have the SS. There are some grades of Stainless that machine easily, if you do your homework. We have some beautiful pieces of stainless laying about at the museum, but I wouldn't want to machine any more of it.

The machining of ductile cast iron is so much cleaner than the common stuff, I have a 160mm unmachined cast iron chuck backplate on order from Chronos which I will fit to the Atlas, which has a 1 1/2" X 8? thread like a Boxford, I am not looking forward to the mess.

As for differences between three and four jaw chucks, the physical differences are obvious, so the placement of the fixings and registers varies. My 6 3/4" Pratt with the serrated jaws has three fixing studs directly in line with the centre of the scroll. A four jaw independent is easier to make if the register is inboard of the screw bearing blocks. I notice that the OP's four jaw is the other way round.

 The bolts will only have shear forces on them if you forget to tighten them.

Edited By old mart on 16/09/2019 20:25:53

Edited By old mart on 16/09/2019 20:29:39

I used the Ian Johnson method recently for a different reason. I had a leadscrew for a Tom Senior X axis, which I added about 4" of extra thread on one end. This meant that the uneven wear on the leadscrew was further compounded by some brand new thread. With the compound at zero (parallel), I used the compound to creep to one side of the most worn part of the thread until the tool started rubbing. Then I carried on over the less worn parts in several stages, and re adjusting the compound to cut the other side of the thread. Eventually I ended up with a thread with all the wear equalised. The wear was not so bad as to be noticeable visually, but was quite obvious when using two nuts to minimise backlash. Now, the backlash is minimal, with no tight or slack areas.The thread is 3/4" X 5 ACME, I had to use a travelling steady and a live centre in the tailstock, plus bored soft jaws.

I usually consult thread charts for thread depth, which give an idea of how far to go and also helps to plan the number and depths of the cutting stages. The last threads I cut were of no particular size, the M and F had to be a nice fit, and I made the thread depth to suit the pitch using charts.

Edited By old mart on 16/09/2019 18:59:48