This is our first major video tutorial project with multiple camera views. We shot it in HD (1080p) with High Def cameras and then uploaded it to YouTube in HD (720p) which is as high a quality as YouTube will allow. But even at 720p the video is better than DVD quality.

Please leave your comments via the forum and let us know what you think. Our next videos will be on grinding your own HSS tooling (RH Tool, LH Tool, and Threading Tool), and then we plan to do a multi-cam video on single point threading.

However, your feedback is critical. We want to know your thoughts, good or bad. It would also be helpful to know if there are any other topics that you’d like to see made into videos.

Thanks!

Tyler and Barry

Video #1 of 2: Sharpening Twist Drills By Hand – Introduction

Video #2 of 2: Sharpening Twist Drills By Hand – Sharpening

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This table showing lathe cutting speeds in feet per minute. I use this table to calculate the speed of my lathe and my drills. Yes I am aware they are not as accurate when using them for drills, however they seem to work for me. The proper formula for calculating is as follows:

CS x 12 =   RPM

π x D

CS being ‘Cutting Speed’ which is locate in the table above and ‘D’ meaning diameter of stock

However you can shorten this down to make it easier, π (Pi) has a value of approximately 3.14 and divides into 12 just under 4 times.

So I use this shortened formula for working out my lathe speed.

CS x 4 =  RPM

D

Let say I have 3 inch ally stock and I’m using toolsteel to make the cut.  For roughing the formula would be as follows:

1000 x 4

3.000               =        1333.33 RPM

So 1300 RPM is the rough speed I should be cutting with 3 inch aluminium stock in a lathe.

Now lets say I now have 1.505″ stainless steel and I want to do my finishing cut with toolsteel. The math is as follows:

46 x 4

1.505                   =     122.25 RPM

Easy isn’t it? If your using metric and/or metres a minute for your cutting speed , you might want to convert the numbers above and create your own table.

Hope this helps,

‘MadRep’
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This question comes up occasionally on the forum and I’ve seen it addressed in books, but I’m not sure if I’ve ever seen a video of the process, so I decided to make one.

Setting up your lathe to take very fine cuts is a simple process. The quick version is this: By setting your compound at an angle of between 5° and 6° you’ll be able to use the dial on the compound as a very fine feed, advancing the tool in tenths for every thousandth you turn on the dial.

This is sometimes referred to as “Slewing the compound”. Although I’m not sure how technically accurate the term “to slew” is when talking about lathes. This could be slang for all I know and to make matters worse I’m not sure if it’s American slang or Brittish slang (as I have read dozens of books from both sides of the water), so be careful if you decide to break out the term in a shop full of machinists. You might get some funny looks.

I’ve seen this process described in multiple books, including the Machinist’s Bedside Reader by Guy Lautard, and in Lathework a Complete Course by Harold Hall. Both of which are excellent books. The first book by Lautard shows you the math behind the process I’ve outlined here and uses imperial (inch) measurements. The second book by Hall describes a slightly different method and is written for those who work in metric.

Anyway, if your compound is set at 5.75° and you advance the dial on your compound .001″, the tool bit advances toward the part .0001″ thus taking a very fine cut.

That’s as easy (or as complicated) as it gets. For most of you the image above will be enough of an explanation, but for those who require a little more reinforcement of the concept, here’s a “short” video of the process. I took 8 minutes to explain what should have taken 60 seconds. It seems I need to work on being succinct and not sounding deadpan. But hey, we all have our things to work on, right? Bueler … ?

Setting your compound to exactly 5.75° isn’t critical, somewhere between 5° and 6° will get you very close. You can also use this process for metric cuts.

Do you have a different method that you like to use? Please leave a comment on the forum. We’d like to hear it!

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Soft jaws have several advantages, especially when you need to hold a custom workpiece. For example, you can also make or buy a set of soft jaws and bore them out to the perfect size to hold the workpiece, and since you’ve bored them on lathe, the jaws will hold the part perfectly concentric to the spindle axis.

As you can see from above this can be especially helpful when you want to hold smaller parts made of soft metal.

But what about when you just want to hold a part without marring it? Are expensive/custom soft jaws necessary? NO!

Do you have a soda can lying around? If so you’re in business.

First, cut the can open (carefully) with scissors, and cut the aluminum into strips who’s width roughly match the size of you’re jaws. Make them long enough so that they can wrap around 3 sides of the jaw, and fold them around a piece of metal approximately the same width as your chuck jaws – my 6″ scale is perfect for this.

Next, slip them over the jaws. Folding them gives them a shape that allows them to grip the jaws – that way they stay in place – which is a lot easier than trying to slip pieces in around the part.

Finally, insert your part. You’ll be able to tighten the jaws a bit more than you would be able to normally, but the can is only about .004 thick, so you still need to be careful. Also, if the part spins replace the jaws – they wear through instantly.

I hope that helps! Obviously real shim stock (brass, aluminum, etc) would work as well, but aluminum cans are cheap – and you’ll be recycling at the same time!

Do you have a different method that you like? If so, please share it with our readers on the forum via the link below.

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I wanted to document the process I went through to make my cover but I didn’t want to rehash what Barry had already written, so instead I made a video of the process. So now you can read the steps (Barry’s article) or watch the steps (my video). Both provide you with a cheap, easy and fool-proof method of protecting every major tool in your shop with a custom-fit cover.

Obviously you can adapt this method to virtually any size or shape of lathe, mill, etc – you’ll just need to buy an appropriately sized tarp to make your pattern.

Here’s the video.

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Machines are expensive. Dust is abrasive. Don’t believe me? Go get that old motorcycle helmet that Aunt Beunice gave you for your 16^th birthday after you bought that 125cc Honda Combat Wombat with your paper route money. Yeah, the snazzy lime green one. See all that dust on the face shield? Give it a good rub and telephone me to tell me it didn’t scratch it up.

You keep your calipers and micrometers in a toolbox right? Those baseball cards that Grampa gave you go into his footlocker right? You keep your money in a bank right? So what do you do with your machinery? If you are like ninety nine percent of amateur machinists you let your machinery sit out in the open, unprotected, cold and lonely.

Next time you are using foul language to describe to a friend how your machine wouldn’t hold the tolerance you wanted it to, look back at how you treated the poor machine. You oughta be ashamed. Why would you put the bench grinder where it would spit abrasive particles onto the lathe? You mean you did woodworking in the same room as your metal machines are stored? Don’t you know that wood chips will soak up all the oil on those precision surfaces and make them rub together? The precision of your machinery is based on the wear that occurs to the ways and other sliding surfaces. So when you are done hanging your head, when your lip stops quivering, I will help you pay your penance. Even you can seek forgiveness at the chapel of the recovering machine abuser.

The only way to fix up your Karma is to make covers for your machinery. Yeah, a lathe cozy. This sounds dumb until you think about it. Like “Don’t run with the scissors,” sounded dumb until you either thought about it or found out why people told you that. This is the same, you can learn the easy way through logic or you can poo poo the idea and pay when your machines will no longer do what they should. I finally got sick of waiting for February 30^th which is when my wife said she would finish my equipment covers and asked her to show me how to sew fabric. This she was perfectly willing to do. It was not that hard to learn. We measured the extreme length, width and height of my Atlas horizontal milling machine and she made a sort of toaster cover shaped thing that fit like snot because the mill was not a perfect cube. Scratching my head I thought up a better way. That is what this article is about.

I took a cheap blue tarp and threw it over the mill. Everywhere there was looseness in the tarp got a row of pins. Eventually the tarp fit it snugly. I cut away all the excess tarp and cut nice and even around the base. Voila! We had made a pattern. We took it into the sewing room and laid cotton duck (fabric) down on the floor and laid the “pattern” over it. Dang! The fabric was too narrow. No Problem, We sewed on an extra ten inches and now it was wide enough. We pinned the pattern to the material, traced around it with a Sharpie marker and cut it out. She showed me how to sew the seams  which was WAY easier than I thought. I had her sew (hem) a piece of clothesline around the base of the cover and it was done. Yay! It fit all the curves and odd surfaces of the mill. It literally was a custom made cover.

Next came the Atlas 7-inch shaper. I decided to document the process and do all of it by myself.  Here are photos of the goofy shape that needed a cover

It is an ungainly thing to try to cover.

Under the tarp it looked like an ostrich trying not to be seen.

See that big flap ‘o nonsense hanging off the front? That is the excess we are trying to get rid of. Gathering all the excess material together then pinning it to isolate extra fabric leads to rows of straight pins pinching off whatever you want to get rid of like this.

Once the excess is pinned you can carve away the extra fabric OUTSIDE the pins with scissors leaving you something better looking like this.

Be sure to write on it before you take it off so that the outside is obvious. Otherwise the seams will show and your buddies will laugh even harder at you. When you trim away the bottom of the cover level with the floor it suddenly looks like a machine cover.

Now the pins can come out and you have a pattern. Lay this on the fabric you have chosen. You can see how I had to add material to get the width problem mentioned above solved.

Trace around the pattern and cut out the fabric. Sew up the seams and sew in the cord around the bottom. You now have custom fit machine covers. In this last photo you can see the incognito shaper on the left before the cord is sewn in around the bottom and the incognito milling machine on the right with the cord sewn in. The cord gives the cover a finished appearance so don’t be an idiot and leave it out.

That’s it! If you have a question or you want to leave a comment please click the “Join the forum discussion on this post” link below to log into the forum topic tied to this post.

- Barry

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