Member postings for ega

A chuck that won't stay on its taper is obviously of no use and any solution is better than none. I found a paragraph in my 1966 edition of the Loctite Design Handbook headed "Adding adhesives to splines and tapers" which seemed promising; however, the text seemed to be concerned with joints where play is present between the components (which may have been present in the OP's case but certainly should not have been).

The Handbook also say that the bond in tapered overlap joints can be "very good".

I have always addressed this problem where possible by the screw method; it's effective and does allow ready dismantling and I have never had any difficulty in drilling the necessary axial hole in the chuck body (chucks on reversing hand power drills are, of course, retained in this way).

A quick OT comment:

I just bought some black pepper in my local UK co-op "packaged in Turkey from pepper produced in Brazil".

I have link belts on both primary and secondary drives on my S7. One advantage over the conventional vee belt is said to be that the link belt won't take up and "memorise" a set if left taut and unused for a period. Replacing the drive to the spindle with a link belt obviously avoids the need to dismantle.

On the other hand, the greater bulk of the link belt may make shifting to and from the top speed pulleys more difficult.

Rather like not brushing your teeth too close to eating!

What about other additives such as moly or Redex?

In his ME manual GHT recounted how he had been challenged on the use of silver steel for his boring bars. Whilst, I think, conceding that they were no stiffer than if made in MS he preferred silver steel for its greater resistance to abrasion and the fact that it was more likely to hold up to nominal diameter (his bars were clamped in eccentric holders and a sloppy fit would have been unhelpful).

Edited By ega on 06/02/2020 14:05:05

If the former, keyed chucks can be secured with a screw.

In the same vein, you could turn up a close-fitting bush and screw it to the underside of the head casting to stabilise the quill.

Did I see somewhere that the additives in EP oils are detrimental to bronze, a material which is sometimes used in geared headstocks?

Thanks for the interesting link. For clarity, I think the bed width remained unchanged when the arrangement for guiding the saddle was changed. The move from narrow guide would have been desirable regardless of the introduction of PXF.

thaiguzzi:

Your machine may have been the elder and larger brother to mine which, according to its plate, was made in Taiwan in 1988.

Incidentally, my impression is that Taiwan is holding its own industrially vis a vis China.

I believe there have been specialist lathes that perform this trick. I do it manually with one hand on the cross slide handle and the other on the pot - rather like the cook and the drummer!

It sounds as though the cheap Asian drill may have become cheaper over time: a friend gave me an old Astra import which had been condemned by his employers on account of the flange connecting the column to the base having cracked in service; this was easily replaced and, despite being rather noisy, it has given good service for some years. Checking the quill at full extension just now revealed no obvious side play.

The main limitation of these machines for me is the overhead in time of setting the speed; there seem to be rather few drills available with rapid speed change.

Strongly agree. How often does a newcomer post a question or request for help that calls for some idea of their location!

But feel free to ramble.

I tend to agree with this but isn't one of the advantages of hand feed that the rate can be varied eg as in facing to centre?

I have a Verdict T500. There is no reversing lever or obvious way of re-setting the stylus; the stylus does, however, move in either direction to give a reading on the dial.

Does anyone actually know whether re-setting on this model is just a matter of using sufficient force on the stylus?

Verdict DTIs used to be made/serviced here in Kent and the firm were helpful at exhibitions.

I recall Martin Cleeve suffered a tee slot breakage whilst parting off on his ML7; characteristically, he proceeded to replace his cross slide with one fabricated from steel.

Myfords apparently thought that their own RTP could be held by a single slot but I prefer the Duplex/GHT use of two.

Good point by old mart about the need to control saddle lift.

Aren't these case-hardened?

PS Just checked the catalogue - they are.

Edited By ega on 29/01/2020 16:00:24

I had not heard of this before I saw the current items for sale. There is some information here:

https://www.newmantools.com/taps/combidie.htm

including the statement that perfect threads are produced without reversing.

This is a hand applied tool and not one I would have much use for but I would be glad to know how the no reversing feature works. Perhaps the holes intersecting the thread are that much bigger?

Edited By ega on 29/01/2020 14:20:34

I expect you are right but one would need a steady hand to avoid disturbing the status quo (I assume they were firm joint calipers).

Presumably, the calipers were for measuring woods?

Kiaora!