Dial Indicator Attachment

[mklotz]

Also doing part off work on my 10X20 bench lathe was impossible, until I procured a 2" plate that it is now bolted too. It used to "walk" on the floor with very light parting operations. It never came with a mounting stand. Then 25 years ago, I purchased a stand from harbor freight intended for their 12x32 lathe. It was 2 sheet metal rectangle boxes with a sheet metal web between. I trimmed the web to length for my shorter lathe. But with any parting cut, the lathe would go into harmonic oscillation. I played with the cutter. Procured other cutters. Never could get a problem free parting to be realized. The 2" thick steel plate fixed this. If I would have made a weldment stand, and bolted it to the floor, that would have fixed this as well.
Steve

Parting off is often problematic for small lathe users. Some suggestions...

Make the tool dead sharp with sufficient relief

Ensure the tool is perpendicular to the lathe axis and on center

Use a lubricant - kerosene for aluminum, sulfurated cutting oil for steel, nothing for brass or cast iron

An improvised lubricant feeder like my...

http://www.homemadetools.net/forum/p...ff-oiler-27738

can provide a steady supply of lubricant

Keep the speed on the low side

If you grind the tip of the tool so that the right corner projects just slightly more than the left, then the burr that exists when the workpiece falls off will be on the stock and not the workpiece. Drive the tool in a tiny bit more and the burr will be cut off the stock.

[mklotz]

Some more thoughts on thumbscrews.

Knurled screws are attractive but can be uncomfortable if they must be gripped tightly to do their job. If only for occasional, delicate adjustments, like a micrometer barrel, they're fine but for frequent adjustments requiring a firm grip (e.g. the handles on a threading die stock) they can be uncomfortable.

One solution is to run a file over the knurls after they've been formed. This will knock the tops off the little pyramids that form the knurl and make it more comfortable to handle.

For beefier stuff I prefer fluting. It provides a firm grip and is much easier on the hands. An example is my tripod quick release handle...

http://www.homemadetools.net/forum/t...-release-27215

[Ralphxyz]

Marv, re: "grind the tip of the tool so that the right corner projects just slightly more than the left, then the burr that exists when the workpiece falls off will be on the stock and not the workpiece"

Why not just the opposite then there is no burr to remove?
Ralph

[metric_taper]

Parting off is often problematic for small lathe users. Some suggestions...
<snip>

I recall Tee-Nut saying that the parting operation should sound like bacon frying. When the machine don't dance on the floor, you can really hear that.

[desbromilow]

Ralph,

it's generally accepted that the piece you've just parted off will be difficult to rechuck, so making that piece not have the pip is good practise - the remaining stock (still in the chuck) can then be refaced and the pip from the parting removed.

there is generally a pip because of the angled grind of the parting tool (causing the chip to curl), or due to the piece breaking away once the diameter is reduced enough

Des

Marv, re: "grind the tip of the tool so that the right corner projects just slightly more than the left, then the burr that exists when the workpiece falls off will be on the stock and not the workpiece"

Why not just the opposite then there is no burr to remove?
Ralph

[mklotz]

Marv, re: "grind the tip of the tool so that the right corner projects just slightly more than the left, then the burr that exists when the workpiece falls off will be on the stock and not the workpiece"

Why not just the opposite then there is no burr to remove?

Let me try to explain a bit more clearly, Ralph.

When parting there is almost always a burr generated when the part is freed from the parent material, even with a squarely ground tool. As the cut approaches the center the remaining material gets thinner and thinner, thus weaker and weaker. At some point before the cut is completed, the material is so weak that it fractures before the cut can be completed, thus leaving the burr, material that didn't have a chance to be cut before the fracture occurred.

If the burr is on the part, it can be awkward to remove, perhaps necessitating rechucking. If the burr is left on the stock, it can be removed easily by simply turning the tool a bit farther until it cuts to center.

By grinding the tool with a right-hand leading edge, the part will be cut loose before the remaining stock at the stock side of the cut gets weak enough to fracture, thus assuring that the burr is left on the stock.

[Jon]

Congratulations rossbotics - your Dial Indicator Attachment is the Homemade Tool of the Week!

Another strong week, with a rare two-in-a-row win for rossbotics after last week's Tilting Dividing Fixture Homemade Tool of the Week by rossbotics. rossbotics joins three other tool builders who have also won Homemade Tool of the Week in back-to-back weeks:

Brendon - Marking Gauge on 7/17/15 followed by Dovetailing Bench on 7/24/15.

mklotz - Bench Block Enhancements on 5/27/16 followed by Model Cement Mixer on 6/3/16.

tonyfoale - Horizontal Milling Machine on 12/23/16 followed by Drum Brake Grinder on 12/30/16.

Like the Superbowl, nobody has ever won three in a row.


Some nice picks from this week: a Shop Air Cleaner by mr95gst, a Powered X-Axis by bobs409, a Tube Notching Method by Tuomas, a Clamp Plate Forming Tool by KustomsbyKent, and a Hardware Storage Unit by bobs409. There were three good builds by Frank S - Alignment and Distance Tool, Backhoe Receiver Hitch, and a Drill Bit Extension. And, we also saw a nice Rotating Tail Stock Chuck by jjr2001, who is rapidly climbing the Top Builders List with 118 total homemade tools.


rossbotics - you'll be receiving a $25 online gift card, in your choice of Amazon, PayPal, or bitcoin. Please PM me your current email address and gift card choice and I'll get it sent over right away.

That's win #15 for rossbotics! Here are all of your wins:

Height and Square Gauge by rossbotics

tags: gauge, square, dial indicator, height gauge

Filing Machine by rossbotics

tags: file, gunsmithing, motor

Slitting Saw Arbor by rossbotics

tags: machining, arbor, slitting saw

Threading Insert Tool Holder by rossbotics

tags: lathe, tool holder, threading

Toolmaker's Vise by rossbotics

tags: vise, machining

Indexing Fixture by rossbotics

tags: gears, indexing unit, fixture

Gear Cutter Arbor by rossbotics

tags: arbor, gears, cutting tool

Direct Indexing Sharpening Fixture by rossbotics

tags: sharpening, fixture

Tool Post Grinder by rossbotics

tags: grinder, pulley, tool post

End Mill Sharpening Fixture by rossbotics

tags: fixture

Dial Making Fixture by rossbotics

tags: fixture

Brass Hammer by rossbotics

tags: hammer, machining

Universal Grinding Fixture by rossbotics

tags: grinding, fixture

Tilting Dividing Fixture by rossbotics

tags: indexing unit, fixture

Dial Indicator Attachment by rossbotics

tags: milling, dial indicator

[Ralphxyz]

I understand, I was thinking the fall off piece is just waste, the part left on the lathe was the work piece.

Of course I am brand brand new to machining so I have not even done a project on my lathe yet.

Ralph

[mklotz]

Congratulations, Doug; very well deserved.

[rossbotics]

Thank You Very Much, Marv