Dial Indicator Attachment

[wizard69]

First thanks to Doug for this great post!

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.

I'm not a fan of knurled nuts/screws at all.

Like you I prefer something else, there are actually lots of ideas here each with its disadvantages and advantages.

For industry work we often use "Shear Lok" press on knobs. Of course this means buying the press on knobs.

When I need to make a knob I do prefer a flutted design myself or maybe better described as lobes. The big problem here is the sharp edges which have to be blended in. Add a few holes around the perimeter of Tommy bars when you over tighten things and need little extra leverage to unscrew.

Sometime the big knob doesn't work well so a stud with Tommy bar can be a good choice. I call this the C-Clamp look.

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.

I like fairly heavy blending and often use course Scotch Brite wheels on a right angle die grinder.

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

Sometimes when crude will do welding a bar across the top of a cap screw can produce a rugged and quick solution.

In any event I'm liking all these ideas. This has been a great thread already.

[wizard69]

Thank You Very Much, Marv

Really thank you! I may not go this route but alternative ideas are what keeps the idea factory working.

[rossbotics]

This will be a great place for you to learn how to run your Lathe Ralphxyz

[NortonDommi]

Excellent presentation. Thanks

[rossbotics]

Thank You Norton

[HamishH]

What a great help in the all mill set-ups. No need to find a convenient flat spot on the machinate affix a magnetic base holding the indicator. Thanks

[metric_taper]

Attachment 17856

Doug, did you do any special fixturing to machine the slot on the Swing Arm? My method would be to put in a 8" milling vise with parallels supporting the edges. I'm concerned that clamping pressure may warp the center of the part when the end mill breaks through on the final pass, and cuts the slot wider in the middle of the part. I've no experience with O1 flat stock, only O1 drill rod. I assume there is little stresses internal, but don't know for sure.

For heat treat was there any special treatment to reduce warpage of the long slot? I have a heat treat furnace (a Paragon kiln). I'm thinking I would put it on a fire brick so it's supported along it's length. And do a temper to 400F.

Thanks

[rossbotics]

Hi Taper
That's what I did I used two 1/2" X 1" X 8" hardened parallels on there edge and spaced them up on parallels from the bottom of the mill vise, and spaced up the swing arm as well, this way equal pressure was applied throughout the swing arm for milling the slot, worked great.

O-1 tool steel is not difficult to heat treat at all, beings you have a furnace just heat it up to around 1500 deg, and quench her in oil then clean it up nice and shinny and reheat it until it turns to a straw color and quench it once more, it's now tempered, here's a link to all the specs, http://buffaloprecision.com/data_sheets/DSO1TSbpp.pdf

[metric_taper]

Hi Taper
That's what I did I used two 1/2" X 1" X 8" hardened parallels on there edge and spaced them up on parallels from the bottom of the mill vise, and spaced up the swing arm as well, this way equal pressure was applied throughout the swing arm for milling the slot, worked great.

O-1 tool steel is not difficult to heat treat at all, beings you have a furnace just heat it up to around 1500 deg, and quench her in oil then clean it up nice and shinny and reheat it until it turns to a straw color and quench it once more, it's now tempered, here's a link to all the specs, http://buffaloprecision.com/data_sheets/DSO1TSbpp.pdf

I've made lathe form tools from O-1 drill rod. As well shafts for needle bearings to run on, and sand blast nozzles (which I don't temper). I did have one mishap, I made a replacement bandsaw blade tension bolt for my 4x6 import saw. The original bolt stripped out. I thought, "I don't need to temper this", well it didn't take to long for the shaft just above the threads to fail. Snapped right off. It did teach me that tempering was a required process if you don't want it to shatter like glass.

So what is your method of cleaning up the burnt oil residue? I've found removal to be a PITA to get a clean surface.

[rossbotics]

I've made lathe form tools from O-1 drill rod. As well shafts for needle bearings to run on, and sand blast nozzles (which I don't temper). I did have one mishap, I made a replacement bandsaw blade tension bolt for my 4x6 import saw. The original bolt stripped out. I thought, "I don't need to temper this", well it didn't take to long for the shaft just above the threads to fail. Snapped right off. It did teach me that tempering was a required process if you don't want it to shatter like glass.

So what is your method of cleaning up the burnt oil residue? I've found removal to be a PITA to get a clean surface.

After it's cooled down I just wipe it off and go to the grinder where I have a wire wheel and get the crud off, I then take some 220 grit by hand and clean it up, heat it back up to a straw color and quench her once more, I have two surface plates of different sizes and only use them for inspection Etc. go down to your local granite shop and get you one of there drops, they gave me mine, I got two pieces of that stuff there about 14" X 16"just for laying down full sheets of wet dry 600-800-1000 and do polishing or whatever on, this stuff is incredibly flat, you can use this plate like a lap with a piece of 600 wet dry, or you can grind it all over like I did, this is the best way, If you find your slot closed a little bit from the heat treating you can put it back in the mill with the same parallel setup and with a 1/4" carbide end mill and clean the slot up.

Hope this helps