Member postings for Andyf

Looking at the second pic, where the cover is off, I think it might be one continuous belt, cunningly arranged so that the pulleys all run in the same direction. . But if that is true, why such complication?

Andy

For aluminium, a much greater top rake than that used for steel is often recommended - at least 15 deg, and up to as much as 35 deg. If your tools were pre-ground for steel, .the angle will be much less.

That said, I don't use anything special for Al, and my results are OK (though my standards are not terribly high!).

Are you using a fine power feed, or winding the saddle along by hand? If the latter, try cranking very slowly indeed.

One problem with Al is that it is gummy, and a blob of it can build up on the tool tip, altering the geometry and impeding chip clearance. Using WD40 or paraffin helps to prevent the build-up.

Andy.

I'd like to second your recommendation about ball bearing closing nuts, Harold; after learning about them a couple of years ago, I bought one and it is much easier to use than the solid variety.

In your article, you also mentioned imperial ER collets, and I intend to get some to assist with imperial shanked tooling on my vertical miller. While the nut is being tightened, a metric shank will self-hold in a metric collet, but an imperial shank will fall out unless held up with a third hand while the slack is taken up.

Andy

...and if that isn't shiny enough, finish off with toothpaste.

As to solvent welding, a pal of mine stuck some Perspex together for me, and said he'd used ether. if my memory served me right. Or maybe I'm getting my anaesthetics confused.

Andy

I once worked out with trig that to get an ER collet to collapse by 1mm, it should have about 4mm of the 8 degree taper projecting out of the chuck when it's inserted gently (i.e. before compression begins). Obviously, the projection can only be measured with the closing nut off.

This applies to ERs with a 1mm "leeway" in all sizes from ER11 to ER40. Those which are only supposed to collapse by 0.5mm will only need 2mm projection.

Andy

Think you may be confusing the 55mm length with the 175mm (six and a half inch) diameter, Peter.

Sorry I can't help, David; I've no rolling machine..

Andy

Excellent analysis, John.

And when all is said and done, Ketan is far better qualified than anyone else on this forum when it comes to making business decisions about Arc Euro Trade.

Andy

Your link seems to go through to a KB electronics manual, Steve.

The S8010L SCRs are available from Farnell (order code 1869397), though it might not be a bad idea to use S8020Ls (order code1869399) instead; they are rated 20A rather than 10A.

Farnell also do a D8020L diode, again 20A (part no 1456539). I couldn't find a D8010L 10A one.

The 80 seems to indicate 800V, and the 10 or 20 the amps rating.

All made by Littelfuse, as you say.

Andy

Martin,

Looking at the chart on page 8 of the KBIC series manual , I would choose a KBIC 240 if you are on 230VAC mains, specifying the appropriate "horesepower resistor" to suit your motor from the list on page 11 - probably a 9838 or a 9839.

I bought a KBIC 240D to power a 2HP motor, and one of those would do equally as well. If the prices are similar it might be a better choice. Its higher rated components would stand more accidental abuse.

Andy

I too have a Warco lathe with a cloned version of an old-style KB board (leaded components, rather than the surface mount ones now favoured by KB). The clone was labelled (I think) "Best Controls" of Taiwan. For a 2HP motor on another machine, I bought a KBIC 240D board, and if the Warco one blows up and can't be repaired, I'll get another of those and fit it in the lathe. It is indeed a pin-for pin replacement, the spade connectors being in the same relative positions.

I put some ramblings about these boards on my website HERE . On the lower half of the page is a schematic for the KB,with a parts list and a labelled photo by way of a parts placement diagram.

Andy

One of these days I'm going to treat myself to an LH caliper gauge.Ergonomically, it would be a bit better when measuring the diameter of something held in the lathe chuck.

Andy

One of my Aldi specials has auto switch-on as soon as the slide is moved, auto switch-off when ignored for a few minutes and remembers what it was reading when it turned itself off. This memory must mean that the display is the only thing which actually turns off, but I only have to replace its little watch battery every 3 months or so with another from those blister packs from the pound shop, containing about 80 batteries of which 60 are in redundant sizes.

I'm not suggesting £9 Aldi calipers are the most accurate of instruments, but they ain't bad for the money. When real accuracy is needed, there's no substitute for a proper micrometer.

Andy

My other ER25 chuck, which incorporates a flange to match the flanged spindle of a Chinese lathe, needed its taper skimming true, Chris. I had no problem doing that on the lathe with an HSS tool.

The Myford-style one on my miller doesn't seem to be hardened, either, if the scratch I've just put on its outer rim with an old drill bit is any guide. But they may vary between manufacturers or batches.

Andy

I don't have a Myford, but the spindle nose on my Dore Westbury emulates the Myford one. I had a set of ER25s, so I bought a screw-on collet chuck from from RDG. I've been very happy with it; no more hammering away on the drawbar to free off MT2 collets. That said, zero runout isn't quite so important for a milling cutter as it is on a lathe.

Russell suggested making your own, but that would involve making up a dummy spindle nose to test the thread and register for fit. A compromise might be to buy one and if necessary re-bore the 8 degree taper (16 degree included) on the lathe.

Andy

Chris, for centring in a 4-jaw, I find a finger-type DTI with a 0.01mm (that's less than half a thou) perfectly adequate. I have never used one with 0.001mm divisions, but I suspect that the main object (to adjust the 4-jaw until the DTI needle doesn't move as the chuck is rotated) might be harder to achieve because the instrument was picking up too much confusing "noise" from the surface of the work, and the effects of your hand in the chuch as you turn it.

The difficult bit with most finger DTIs is getting them positioned. My magnetic stand with articulated arms is difficult to manoeuvre on my small lathe, so I made up a holder which fits in the toolpost. This allows the finger to be brought gently into contact using the cross-slide and topslide.

Finally, the instructions on many DTIs don't mention that the angle of the finger vis-a-vis the indicator body can be adjusted. It is a friction fit to the rest of the mechanism, and (though at first you might think damage will be caused) a firm push will turn it so it is at up to an angle of 90 degrees either way. Correspondence on other forums show that a substantial minority of hobbyists don't realise this and have only ever used their DTIs with the fingers aligned as they were when first taken out of the box.

Andy;

For those without a dovetail cutter, Norman Patent toolholders are easy to make, but use a lot of metal by the time you have made a few.

This one-off "lathe to die for", made by Rolls Royce, has one fitted LINK.

Here's how to make them on a minilathe LINK .

Andy

Before I got my curvaceous ones, I often used some steel box strapping that came round something or other. It proved surprisingly consistent in width, and got many jobs to the right height in the milling vice, where it would stand upright if a gentle bend was put on it. Had to be careful when tapping the work down on it, though.

Andy

You get what you pay for with parallels. Holding any two of my cheapo set together and up to the light is ... err.. enlightening, unless I pick a pair where the curves match.

Andy

We were after impressive bangs, rather than fires, Neil. We didn't get further than weedkiller and icing sugar, and that was getting a bit tricky because (if I remember rightly) it can ignite spontaneously. One of the gang was known as Copperknob, after a bit of shrapnel from the device he made of gunpowder packed into a length of plumbing pipe (known as a pipe bomb nowadays, I think) was surgically removed from his member. Happily, he went on to father several children in later life.

David, I too had to surrender my .22 pistol, an S&W Model 41. Not too big a wrench, though, because I couldn't hit the town I lived in with it, and like you I am more of a rifle shooter. Also, it cost me £80 secondhand, and the £800 I received six years later softened the blow somewhat.

Andy

Hi Mike,

Thor's suggested method is the one I use, though it does rely on the side of the topslide which the indicator bears on being parallel to to the dovetail within, and care needs to be taken to mount the indicator horizontally. For anyone who (like me) was daydreaming during the trig lessons, the Right-Angled Triangle calculator HERE can be useful.

Andy

PS. The longer the distance over which you take the measurement, the better. Do the trig for as big a triangle as the length of your topslide permits.

Edited By Andyf on 27/08/2012 09:29:27