Here is a list of all the postings ega has made in our forums. Click on a thread name to jump to the thread.
|Thread: Myford ML4|
I found only one very short thread which didn't cover the points which came to mind when I saw your suggestion.
I have no experience of Poly-V apart from those under the bonnet and in the washing machine but did wonder how they stand up to operating in an oily environment. Also, I understand that they should be run considerably tighter than conventional vee belts thus increasing the pull on the spindle.
|Thread: How to fit a taper pin?|
It may also be good idea to find some means of identifying the small end for when you want to remove it.
|Thread: A 'Starter Kit' for a Stent T&C?|
I would be very interested to know where to buy one of those special oxide sticks. Are they also capable of dressing CBN wheels, I wonder?
|Thread: Tailstock and other tooling by Martin Cleeve|
Excellent photos in my opinion. They certainly demonstrate the high standard of finish MC achieved despite fabricating from MS sections rather than using castings. The overall effect is enhanced by the lathe's finish in Myford Green rather than the "correct" gray colour; I made the same decision when re-building my own machine some years ago.
The relevant constructional articles for the tailstock are in MEs for 12 and 26 July 1956.
Given that MC was a proponent of the swing clear toolpost it is perhaps surprising that he seems not to have thought of the type of screwcutting toolholder that swings up at the end of the cut - sorry, I can't immediately recall what these are usually called!
|Thread: morse taper sticking|
Again, thanks. Oddly enough I couldn't see Wink 2 in that list.
Thanks for the workaround.
A further thought: the instruction to substitute the unwanted smiley is not executed until the text is posted which is perhaps why some forums incorporate a preview. The preview also gives an opportunity to deploy the blue pencil before going public.
Thanks for enlightening me. It would be helpful if there were a list of these features or, better, the facility to turn them off.
Does anyone know why a standard right bracket becomes a Smiley (as in my recent post in this thread)?
I like the idea of Thor with a big copper hammer (apparently named "Mjolnir" but not the practice of "flogging the draw bar". My very basic mill/drill is now fitted with a self-extracting draw bar which I use to remove most tooling; other tools are removed via the slot in the quill with the appropriate tapered drift.
On the Super Seven I use a lever-operated tailstock with resident sliding hammer but I still have to tap the drawbar for headstock tooling.
I never oil or grease MT tapers. There was a suggestion that suspect shanks should be inserted with a paper slip but I have never tried this.
|Thread: Arc Euro Trade ML7 cross slide leadscrew modification|
Isn't your backlash in the nut/leadscrew?
GHT wrote the book on improving Myford cross-slides.
|Thread: Painting aluminium|
I used Hammerite Special Metals Primer available from Halfords and no doubt elsewhere on the aluminium castings of my Speedy recumbent trike. You can overpaint with "most paints" and clean brushes with water. My topcoat is still there.
|Thread: collet chuck|
garrygun said "affordable". I imagine you know more about this than I do so what would you suggest?
Incidentally, in my post what was intended to be a right bracket has come out as an emoticon.
My vintage Willson slantbed came with a Burnerd Multisize collet chuck and collets designated MC3 -13 (1.125" - 1.5". These look similar to the EC collets mentioned by KWIL and I was interested to see from the Rotagrip website that EC collets can be used with hexagonal as well as smooth round stock. If you have the money you can also get collets with serrated jaws for gripping black bar, etc.
Depending upon what is meant by "affordable", I would consider a taper-mounted ER40 chuck and collets (range 3-26mm).
|Thread: Modern taps.......|
Ian S C:
Sorry if I wasn't clear - I did find your table in your photo album. I see you have now been able to transfer the photo to this thread, something I have yet to attempt.
I did, however, produce a thread in softish aluminium without difficulty. As it happens, my Roltap brand tool turned out to be marked with a tap drill size - 7.4mm - and I actually used 7.35 which was my nearest drill and fell neatly between the high and low range figures. Under a lens the thread appeared to be not quite fully formed.
Harold Hall makes some interesting comments including that a good quality lubricant, not a cutting oil, must be used; my favourite Rocol RTD claims to be suitable for "forming operations"
I realize I have committed the all-too-common sin of asking for information which I should perhaps have first looked up myself. The up side is that the many see potentially useful material rather than just the one.
I looked out my single 5/16" 24 UNF thread-forming tap and ran all three methods of determining the correct tap drill size with results varying between 7.3mm and 7.4mm. This might seem quite a large range but there is the variable of thread depth to consider; I used 75% for the Guhring calculator.
I also checked three other possible hardcopy sources:
Machinery's Handbook 1943 - apparently unknown then
Newnes Mechanical Engineer's Pocket Book 1997 - not mentioned
Tubal Cain's Handbook - not mentioned so far as I could see but he was very keen on the correct size for conventional taps
Harold Hall's Data Book (WPS 42) - he calls them fluteless and gives 7.3mm
Now off to the workshop to form a thread with the thought in mind that these taps presumably require a relatively large degree of axial pressure.
Many thanks to Versaboss, Andrew Johnston and Ian S C for their information.
Prompted by the original post I searched the forum for "TiN coating" and was surprised to get no results. What do the knowledgeable say about this modern fashion?
Andrew Johnston: I have one of these thread-forming taps and read your comments with interest; does any one publish tables of recommended tapping sizes for these or do you just go on progressively reducing the hole size until a full form thread is achieved (and then stop!)?
|Thread: Case hardening|
Thank you - that seems very clear. The tip of a push rod would seem to be an ideal application but when a larger surface is involved only the last part treated seems likely to be hot enough to gain from the quenching. I shall therefore re-heat all over before quenching in future.
Thanks for the further information.
Thanks for your post. What intrigued me about this method was that I had always understood that case hardening was a two-stage process - first introduce the carbon under heat then quench to complete. I seemed to get some kind of effect without quenching. Tubal Cain (WPS1) is very good on this subject and makes a good argument for choosing case hardening mild steel over through hardening silver steel, etc.
I agree that hard on hard seems wrong and, in any event, suspect you know more about this than I. However, one authority (the late Cliff Bower) said "clamping screws for tool-posts should always be made of high-tensile and case hardened material and the lower ends bevelled neatly". He went on to suggest drilling the ends and inserting a standard (presumably, hardened) steel ball-bearing making the interesting point that screws treated in this way do not tend to shift the toolshank when tightened.
I personally use standard HT capscrews treated as you suggest and try to avoid overtightening.
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