Here is a list of all the postings Dusty has made in our forums. Click on a thread name to jump to the thread.
|Thread: A glossary of ME terms|
Remember when polishing with abrasive cloth and paper, each change of grade must be at right angles to the previous grade. What you should see is the scratches caused by the previous polishing at right angles to your efforts. When you can no longer see any scratches that is the time to change to a finer grade of cloth/paper. Again at right angles to the way you were working. Polishing round objects is a bit problematic, if you are just polishing and not concerned with maintaining a dimension then just keep the cloth on the move vigorously with the lathe running fairly slow, do not be tempted to dwell as you will polish grooves into the workpiece, you should end up with a figure of eight look to the surface. Change of cloth reverse the lathe. Do not be tempted to start with too coarse a grade of cloth, if it is not coarse enough you will soon see. When polishing do not back the cloth with a file, one slip and you will spend ages removing the file mark. A piece of wood 3/4" wide x 5/16" thick and 10" long, shape the end like a cold chisel, take your cloth and tear it twice the width of your wood, double it over lengthwise and place it over the wood so that one side of the abrasive is against the wood fold the end over the wood so that you have about 2" you can hold onto. Then start polishing with one of the chisel edges. When the cloth becomes clogged move it to a fresh place.
|Thread: Studs for QCTP Holders|
When changing to socket head cap screws remove the first two or three threads down to core diameter. This will ensure you can remove the screws at any future time.
|Thread: BBC TV show that might well appeal to ME readers|
If its on Tinternet then it should be possible to see it. Pull up BBC home page click iplayer( top right). You will then get iplayer home page, in the index click 'B' thats where you will find The boat that Guy built. Yes , you and I know it should be under 'T' but thats the Beeb
This is entertainment, as Steve Garnett says it really is 'the world of make believe'. Having said that , if it encorages just a few people to take an interest in our heritage or a few of us learn from it then it is worthwhile. At the end of the day it may be that some youngsters (anyone under 40 in my book) will take up any form of craft shown, then it will have been a good days work by the Beeb. 'Voice over' is a skill and T.V. companys pay a lot of money even for Actors who are not well known, to perform this service.
As long as the basic facts are correct then to my mind a little bit of cheating to tell the story is acceptable i.e. the cast iron pot.
|Thread: Bench grinder flanges - to fix or not to fix?|
I read this as advice, not as a legal requirement ,as much of the H.S.E. stuff is. They then use the advice as a stick to beat you with when something goes wrong. I agree with you that 'best practice' is what should happen but as we all know we live in the real world where we fall down sometimes.
|Thread: Some thoughts on Model Engineering|
I have to agree with Kwil about Americanisms creeping into our language, we have a perfectly good vocabulary why import from the other side of the pond words and phrases that have no part in the English language. But my pet hate is when Model Engineers refer to the milling machine as a miller. It is only ever a milling machine or mill, a miller is the person who operates the milling machine.
Thats it, I have done my grumpy old man bit for today.
|Thread: Identification of a metal|
Have you tried machining it yet? If, as you state it looks like brass and you have trouble maching it with negative rake tools, it could be Muntz metal. This I understand from my benifactor was sometimes used to make non-spark tools for use onboard oil tankers. Yes I have a lump and it is a bit of a pig to machine. My piece also has a cast surface and looks just like brass, it does not have the red tinge associated with the cast bronzes. I maybe wide of the mark, but it is a thought. I am unable to ask my benifactor as he now reside in the great workshop in the sky. I have tried machining it as if it were steel, this seems to work. The only way of knowing what it is, chemical analysis.
|Thread: Colchester Bantam Lathe|
I was not advocating that the stop should not be tightened properly when in normal use. Just for the trial run. Once Richard is happy with the operation then the stop as you say should be clamped up firmly.
You do not say which lathe you have. Most lathes used by Model Engineers do not have the facility for half nuts to automatically disengage. These features are generally only found on the more expensive or larger lathes. If your lathe is so fitted then as Chris sugests try it first. Do not clamp the stop to tightly to the bed so that if the worst happens you do not damage the lathe. Having read the header I see that it is a Bantam.
Edited By Dusty on 21/02/2011 09:34:39
|Thread: Eccentric Rod Dimension|
It is for this very reason that I have opted to purchase a set of drawings. Yes, they are expensive, but to maintain your sanity and keep your blood pressure down I think it is cheap. I can assure you, that having made a loco from magazine published drawings it will not take you long to realise that it is a worthwhile expenditure. It will not only save you money in scrapped components, but a more precious commodity time. No, I do not have any connection with the drawing supplier other than as a customer.
Nick whilst I go along with your 'errata' page, the end of the series will be for a few constructors, a bit to late.I do not include myself in that, but from reading these posts quite a few are keeping up with the series. It is a good job that Ray is keeping an eye on things.
|Thread: Touching down tool to work when turning|
Just for the record I am not advocating bashing hell out of ball handles or handwheels with a large spanner. I to have seen machines abused by their operators and am in complete agreement with you that machines should not be treated in this manner. I have used my piece of brass bar for many years and my handwheel has not the slightest mark on it. Lets face it only once in a blue moon do I need to put a scraping cut on and then it is just a gentle tap with my brass bar. The hand method does not work for me either, probably because my handwheel is only 2" in dia and I have rather large hands. All I am trying tyo say is, that it is a method that can be employed if the need arises.
Hold the wheel with your left hand, keeping a slight pressure on the feed screw, it is really only maintaining contact. I tap the handwheel at about 1 o'clock on the edge of the wheel.The tap is a vertical hit on the hand wheel, you are not trying to knock the handwheel round. I would mention that it does not work if you are using tip tools to scrape the last few tenths from a job. Tip tools are not designed to cut such small amounts. H.S.S. properly ground and set on centre height is the answer. I suppose that 'the spanner' method is using kinetics.
Sorry David, the" it saves you money "was a bit tongue in the cheek.
C'mon guys why are you making this so b****y complicated. I use a method very similar to Jeff Dayman and his cigarette paper, but I keep the lathe running. The secret is do not get the 'fag paper' wet. Once this position has been established I then paint the job with layout blue. This must be allowed to dry, I use layout blue as opposed to felt tip as it is a thicker film. I then advance the tool until it shows a witness in the blue. The method I use for advancing the tool is known as the 'spanner method' I was taught this by a very experienced turner. The method is as follows Take the cross slide handwheel and remove any backlash, now holding the handwheel in this position you tap the hand wheel with a spanner (in my case a 5" length of 1/2" brass bar) with a little bit of practice you can advance the tool by a tenth of a thou or two. Try it you will be suprised how easy it is.
Tip of the day. Tear the cigarette paper in half lengthways, it is easier to control, has less drag and most of all it saves you money.
|Thread: More On Crankshaft Grinding|
I am sorry but I am the conveyer of duff info. It is not ABCO but ABTEC who supply grinding wheels.
I take it that your air motor rotates at 5500 rpm. I know that some of these small air motors rotate at speeds in excess of 25000 rpm if yours is one of these forget it. I do not know of a grinding wheel of about 4" dia, as I suspect that is what you would need standing that sort of speed. I would speak with one of the specialist grinding wheel suppliers if you are rotating at 5500. Try ABCO, just a satisfied customer. Providing you only leave a few thou to remove by grinding then you should be able to grind it in one go.
|Thread: Have broken a cast bit of my lathe - any hope of a repair?|
I know it is slamming the stable door after the horse has bolted, but it may help others.
Any split clamp or bearing should have a shim fitted in the split to prevent this type of breakage.
First you should adjust the bearing or clamp to suit. Now measure the width of the split, make up a shim so that it is a good tight fit in the split. Put in the hole/s for the clamp bolt/stud insert the shim and Bob's uncle. You should find that the bearing/clamp is adjusted perfectly. Do not be tempted to make the shim to slack if it is a clamp as just a few thou can cause the type of fracture we have seen.
I suppose I should go to the workshop and make my shims now as I have a couple of things with split clamps.
|Thread: MT2 collet slipping|
I can only think of two things that could be wrong. First is that the collet is oversize at the back where it fits into the taper, if this is the case you will never get it to close properly. Ideally the collet should be slightly oversize at the front. The second thing is the drawbar, make sure that it will pull the collet up tight and not jamb on the thread. If you remove the collet and drawbar from the lathe screw the collet right onto the drawbar, then measure that the length from the front of the collet to the shoulder on the drawbar is less than the length of the lathe spindle. I have assumed that you are not using a metric collet for an imperial cutter.
|Thread: Delapena Hone|
It might be worth contacting Delapena themselves. If you don't ask you don't get.
Most of these firms have an archive of old literature they may be willing to supply you with a copy. I expect at a cost, I suppose it depends how much you want it then. It may be that their spares dept may have one.
|Thread: Parting off on Myford lathes|
Turning by hand! with the best will in the world you are not going to get a smooth power transition to the workpiece, you might think it is smooth but it will not be. You have started your judder, you are going downhill from that moment on.
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