2015 POTD Thread Archive

[turnitupper]

Today I needed a steel “washer” of about 4” OD and 2.03” ID. I used a 4 1/4” hole saw to cut a round slug from a sheet of 11 gauge (1/8” steel). Chucked it in the lathe and used a 2” hole saw to cut a slightly undersized ID. The 2” hole saw would have hit the flats of the external jaws, but I routinely cut from both sides when using hole saws, so as to get a cleaner result.

The problem then was how to bore the ID without running the tool into the jaws. What to use for spacers? AHA! I have a bunch of 8mm tall, 8mm diameter rare earth magnets. Stuck them on the jaw flats, then stuck the part on. The magnets even held the part in position while I tightened the jaws - without having to hold it in place by hand!

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Just for fun, I miked a few of the magnets I have. They all seemed to fall within a .002” range in height. Not too bad.

HOWEVER ... these magnets absolutely LOVE swarf! And any crumbs that get on the magnet may cause the part to wobble. So be aware of this.

What an attractive idea!, and what lateral thinking!.
John.

 

[jrstech]

With the temp hovering around 30 degrees Celsius or 92 F. and humidity levels close to 100%, I spent the weekend in the basement and air conditioned garage. I started at the lathe and finished the 8 tool holders I started a while ago. Made new adjustment shaft, knurled adjusting nut and locking nut for each unit.



When finished, they created another few jobs - where to store them. So I stripped the shelf from the back of the lathe and started fresh.



I recall seeing a setup to hold tool holders somewhere - maybe on this forum but I'm not sure. In any case it's not my idea - I stole it! By now the garage had cooled to the high 70's and was bearable to work in.



Since I haven't bought a collet holder yet I had to chuck the 3/16" bit in the Jacobs chuck. I know I know. I was only cutting .040" deep slots for alignment. I'll finish tomorrow and post the final picture.

 

[joshua43214]

Nice work jrstech!
It occurred to me looking at your pics that you could make up a stamp and die and stamp out some flex washers from steel packing strap to go between the adjusting and locking nuts. I doubt you would even need to harden the die since the metal cuts like butter and you are only making a handful. Handmade washers to go with hand made locking nuts

 

[hman]

As a follow-up to my earlier post about using magnets on a lathe chuck - I just realized that you can also do this trick on the face of the chuck itself. And the price sure whoops the billybedam out of Royal Products' chuck spiders - http://www.amazon.com/Royal-Products-25200-Piece-Standard/dp/B0037QG98G/ref=sr_1_4?ie=UTF8&qid=1437460216&sr=8-4&keywords=royal+products+chuck+spacers

OK, Royal's spacers are flat to within 0.0004, and extend to the center of the chuck. Everything has its trade-offs. And as I'm not swimming in dough, the magnets are pretty good enough.

 

[gjmontll]

Thanks for the great application for these magnets. Here's my enhancement to the concept: When possible, they'd also be great for holding parallels in place (in chuck or milling vise) and this would eliminate/reduce the potential precision issue mentioned in the prior messages.
Now, if we could do something about the swarf attraction? Today, as an experiment, I will put a strong magnet in a small plastic pill bottle and put it beneath the tool bit, on the cover of the cross slide lead screw.
I'll be back later with the results and a picture or two.
Greg

 

[ogberi]

Cut and face some stubby aluminum cylinders, maybe 1/2" in diameter, drill holes in each end, secure magnets in the holes with superglue. If you're careful, you can get the heights identical on all three. The ally will help discourage swarf from sticking to the sides, but it will still hella grip on the ends. You can drill just deep enough that the magnets are flush, or recess them a few thou. Flush is easier to clean, recessed is more accurate dimension-wise.

 

[RJSakowski]

I made knobs for a couple of c-clamps. It is my first attempt at knurling and the first project on my new PM1228.
They got progressively better from right to left.
Fancy, Franko! Much more class than the Tee bar that I have on mine!

Bob

 

[RJSakowski]

Bit of a short story to start, but I finally got to go fishing on Lake Erie last Thursday for perch and possibly walleye. Bought $25 worth of emerald shiner minnows and some fat dew worms for my spinner rigs for the eyes. There were many other boaters spread all over the water. My sonar was marking hundreds of fish - some on bottom and some suspended 25 feet down in 50 foot of water. With thousands of dollars worth of lures and a dozen fishing methods, you would think I could choose one that would entice a fish to bite. For all my time and trouble, between my son and I, I caught one GOBY !

I have had days like that (much too recently for my comfort). That's why they call it fishing instead of catching. However, it is always good to be out on the water. Gotta love those lake perch too!

(How many shiners does $25 buy? I complain when I pay $6 for three dozen fatheads and they only give me six dozen.)

Bob

 

[jrstech]

Nice work jrstech!
It occurred to me looking at your pics that you could make up a stamp and die and stamp out some flex washers from steel packing strap to go between the adjusting and locking nuts. I doubt you would even need to harden the die since the metal cuts like butter and you are only making a handful. Handmade washers to go with hand made locking nuts

Thanks for the compliment. I started removing all the spring washers as my collection of tool holders grew. Once I install a tool bit and center it, I lock it down with a wrench. The spring washer allows a finger tight height adjustment so that it's easier to adjust to center without a wrench when changing cutting tools in the holder. Plus I don't need any more projects! LOL.

(How many shiners does $25 buy? I complain when I pay $6 for three dozen fatheads and they only give me six dozen.)

Bob, we get a scoop or approximately 3 or 4 dozen shiners for $6 - never counted them cause they won't hold still! Three scoops of minnows and a dozen fat earth worms, plus the governments tax = $25.

Referring back to some earlier posts discussing knurling and size charts to determine shaft sizes, I have never had a problem knurling any shaft size up to approx. 3 inches since I made my scissor style knurling tool some ten years ago, without checking a knurling size chart. I just recently had to replace my first set of knurls after knurling a 4 foot chin-up bar of 1.250 316 stainless for a gym.

Here's my new tool holder setup on my lathe as of this morning.

 

[chevydyl]

That's badass john, love it, I need some holders so I'm not always changing tools out and having to adjust heights