Member postings for ega

john carruthers:

Thanks for the additional information about this nice little tool. My query was prompted by wondering how a spiral blade would react to what look like conventional guides; presumably, the spiral is run without guides.

Shame about the supply position but, of course, a good 1/4" blade will cut quite small radii. I, too, am a satisfied Tuffsaws customer.

"but I'm still despairing how we will fit everything into the car"

Neil Wyatt: take heart! If my experience is anything to go by then, over time, the student will realize she doesn't need half that stuff. KWIL's post tends to confirm this.

During the three year period I managed to avoid mentioning that in my case it never occurred to me or my parents that I should get to university other than by my own efforts! She made it all worth while by loving her time there and taking a good degree.

Edited By ega on 23/08/2017 16:54:19

Does it indeed have a spiral blade ie one which cuts in any direction?

Thanks to jimmy b and all the others for this fascinating glimpse into the world of patentese.

Bearing in mind that the original topic was *small* diameter boring bars my sense is that most of the methods of reducing chatter proposed would be impractical. The good old between centres boring bar may be the answer for the amateur.

Interesting video but how many model engineers need a 1" or more diameter boring bar?

The adjustable tuning mechanism was not described. Do you know what principle is used?

Not in my book, although I notice that the photo on page 67 of yours dodges the issue by being monochrome!

I think the Myford cream/yellow is yucky, too and re-painted my ML8 with light green Hammerite.

Andrew:

Thanks for the recommendation about the Hemingway kit.

I didn't like to ask if you had finished your Quorn (!) and hope you will soon be able to get back to it.

Andrew Tinsley:

What floating reamer holder are you using, please?

I assume you are boring before reaming.

I would also be interested to know what allowance you leave for the reamer.

Trust the sciatica is better.

No magic from me, I fear but I did check Salaman's Dictionary to see if I could see your tool - nothing quite like it there.

If it were not for the marking I would say this is a refined, shop-made version of the traditional scratch stock.

I think Preston tools were invariably marked as such. I, too, would like to know more about the registration system.

Clive Hartland:

Yes, the same tip was given to me by a toolmaker friend. I think the effect is rather like setting up a cabinetmaker's scraper.

Nige:

Thanks for your response.

I don't remember whether you have GHT's Model Engineers Workshop Manual which has a truly excellent chapter on boring tools.

I think it would be fair to say that hurry was not what he was about either.

On Rainbows' value for money point, I followed up a recommendation by richardandtracy for boring bars direct from China and now have a 7mm dia bar which must be about as small as is possible with a CCMT06 insert. The cost complete with ten insert was under £8 and on test the bar works quite well. It is long for its diameter at 125 mm but, of course, is used with minimum projection from the holder.

My preference remains for a nicely-tuned bar with HSS bit.

Has anyone mentioned that the push rod avoids the need for a grub screw at the business end of the bar?

Nige: I trust you are enjoying MC's excellent book.

I have just confirmed my recollection that the earlier (ie Neil Hemingway's) catalogue did not contain the claim that "Tension, induced by the pushrod, makes even the smallest tool surprisingly rigid" (and I have not seen this suggestion in relation to other push rod-based designs).

The primary function of the push rod is to secure the cutter, of course, but, instinctively, the claim seems valid; my understanding is that the reverse ie compressing the bar would make it stiffer.

Perhaps the OP should ask Kirk Burwell about this.

PS presumably the claim could be tested empirically.

Edited By ega on 14/08/2017 22:23:52

Edited By ega on 14/08/2017 22:42:51

The Americans often refer to milk paint (casein?) which is apparently the very devil to remove (its use may have antedated the invention of Dr Pepper).

"acrylic" first appeared in the COD in the sixth edition of 1976 where it was both adjective and noun (in that order). My most recent popular dictionary (Chambers Concise) gives it first as a noun! By way of contrast, Collins COBUILD based on computer-analysed word frequency treats acrylic as an adjective.

"Wight" can be a noun.

I am certainly a GOG but I try not to get annoyed by these things.

It looks as though the heaviest safe material is gold?

Andrew Tinsley:

As you say, Perspex is (or was) a brand name. I have photo'd the label from some similar material (about 2 sq ft priced at 35p!)

As you will no doubt see, I have had to put two torn labels together to make substantially one.

Michael Gilligan:

No apology needed in my case - I have missed your input.

I thought from Monoman's post that this was another case of specification creep (you may remember our discussion about Pear's soap). It may be nostalgia but my recent purchase of Jenolite seems less effective than before.

What is the difference between ortho and ordinary acid?

Andrew Tinsley:

I think your hot air gun with cylindrical former is well worth trying. By a modest coincidence, I tested this method of bending acrylic just the other day using the high setting on a cheap B & D hot air gun.

I should perhaps point out that the material is some decades old and its brittleness is apparent from the holes which were probably made with a hole saw. I didn't use a former and just continued heating until the sheet was willing to bend. From previous attempts I know that overheating causes undesirable bubbles.