POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

[dkemppai]

So feeling pretty lazy tonight. Dropped one of the pins into the lathe to try hard turn a rim on it. Actually worked well. Bought the chinese CBN inserts a few years ago (knowing I'd need them eventually!), and finally used them. That stringy chip looks hot coming off of there.



I did spend some time indicating in the chuck, and indicating the part in the chuck. Not perfectly, maybe within a couple tenths. When I faced the outer edge of the rim, you could see the wobble that was indicated on the pin earlier. Now checking it for square, it's within about .00025" over 5 inches of length. So, I guess that error is 50 millionths per inch. Hmmm, I guess that means the pin was running eccentrically, but on parallel to the lathe spindle...


Next step will be to grind a honing plate. Someone had given me a nice heavy steel plate, that had a 1/2" grid machined into it. I ended up giving it to a buddy, but it turns out he hasn't used it so I'm snagging it back to grind a honing plate out of it. I'll probably machine or grind some radial slots in the bottom rim of this pin too, seems like cylinder squares often have that. I can see where it would be nice to collect any debris on the surface plate.

If this first pin turns out OK, I'll try it on the one with the pristine surface next...

 

[twhite]

So feeling pretty lazy tonight. Dropped one of the pins into the lathe to try hard turn a rim on it. Actually worked well. Bought the chinese CBN inserts a few years ago (knowing I'd need them eventually!), and finally used them. That stringy chip looks hot coming off of there.
View attachment 434080


I did spend some time indicating in the chuck, and indicating the part in the chuck. Not perfectly, maybe within a couple tenths. When I faced the outer edge of the rim, you could see the wobble that was indicated on the pin earlier. Now checking it for square, it's within about .00025" over 5 inches of length. So, I guess that error is 50 millionths per inch. Hmmm, I guess that means the pin was running eccentrically, but on parallel to the lathe spindle...
View attachment 434079

Next step will be to grind a honing plate. Someone had given me a nice heavy steel plate, that had a 1/2" grid machined into it. I ended up giving it to a buddy, but it turns out he hasn't used it so I'm snagging it back to grind a honing plate out of it. I'll probably machine or grind some radial slots in the bottom rim of this pin too, seems like cylinder squares often have that. I can see where it would be nice to collect any debris on the surface plate.

If this first pin turns out OK, I'll try it on the one with the pristine surface next...

Looking forward to see you get that dialed in.


Cutting oil is my blood.

 

[GoceKU]

Today, I got closer to powering my big man lathe. That draws big man horsepower, which requires big man components and big man wire.

While it all makes me feel big and manly, I cry big man tears because it can only come from my big man wallet.

I feel you pain, in the big garage i only have single phase power, anything with high power i need to run thick cables and they are very expensive. I did recently score some very nice thick multi strain cabling, a buddy just rent a store and i help him move. In the new place someone has loosely run power for a furnace that they took with them, also we found some more in the old shop. Having a good copper cable on hand is handy.

 

[dkemppai]

Looking forward to see you get that dialed in.

We'll see how it turns out. I think this pin will be more square than my surface plate is flat! Eventually I'd like to have that plate calibrated, but first I need to build a better stand for it, and check the temperature stability...

I've already seen that one of my 'precision' machinist squares is off. So, that will probably need to get fixed. Then anything else that isn't right. I also realized I could use the pin to square off v blocks for use with the surface grinder... ...Owning a surface plate gets expensive (time and $$$), really fast!

 

[GoceKU]

Today i had very little free time left so i decided to do some garage organizing. My air conditioning charging staff was all over so i go me a trolly and mounded the compressor that i use as a vacuum pump, my refrigerant tank and gauges in there box, i used some bailing wire to secure them. Then i arranged my sockets and attachments in the small garage. One ting i did different is to use a grease pencil and outline the tools. I need a lot more organasing both garages are a real mess.

 

[rwdenney]

We'll see how it turns out. I think this pin will be more square than my surface plate is flat! Eventually I'd like to have that plate calibrated, but first I need to build a better stand for it, and check the temperature stability...

I've already seen that one of my 'precision' machinist squares is off. So, that will probably need to get fixed. Then anything else that isn't right. I also realized I could use the pin to square off v blocks for use with the surface grinder... ...Owning a surface plate gets expensive (time and $$$), really fast!

Isn't that the truth! I bought my granite surface plate. Then I had to have surface gauge. Then there were more (and better) 1-2-3 blocks. Then there was the precision angle block (not the "precision" setup squares I had bought at Woodcraft). Then I needed dial test indicators instead of just dial indicators, etc. etc. etc. The tenth-reading mics (okay, I already had those up to 4"), the gauge blocks, then the gauge pins--it never ends.

The issue is this: a good surface plate allows us to make the jump from measuring in thousandths to measuring in tenths. Now, we can actually measure what we machine on a surface grinder, and not just its external mic-able dimensions. We end up having to upgrade everything else.

Woodworkers of high expertise work to the 64th--about .016". It takes years of commitment and practice working with wood to attain that accuracy on purpose. Hobby machinists start out chasing thousandths--an order of magnitude more precise than what woodworkers can attempt. And that's good enough for a lot of stuff. Serious machinists or those seeking Stefan Gotteswinter accuracy start seeking accuracy in tenths. That's when they start scanning Craigslist for surface grinders, taking Richard King's scraping classes, and upgrading their indicators, surface plates, and so on. Some go further, seeking accuracy in millionths (or microns). A micron is 40 millionths. Working to that level would require me to replace every single thing in my shop, though maybe I could (sort-of) get away with my Grade B gauge blocks. And I would have to buy an optical flat and learn how to make laps.

Rick "still chasing thousandths" Denney

 

[Nutfarmer]

We used to have a saying at work: machinists made parts to the thousandths of an inch. Tool and die worked to the tenth of a thousandth

 

[Dhal22]

Today i spent some time in the big garage working on cars. Couple small jobs on the little niva but most of the time i spent on the W210, Bumpers got back from paint the paint shop managed to brake on off the tabs between the lights. With the bumper and sideskirts mounted i checked all the systems and the A/C was the only one not working. I vacuum the system then i fill it with R134a, it seams to be working it's cold but demist the windscreen well.
View attachment 433768View attachment 433769

Cars again?

 

[Aaron David]

I spent my shop time sorting out tooling, that which I am keeping vs. that which will go with the old lathe when I sell it to my friend Brian.

Only issue is that there is very little space in my shop right now.

 

[Doug Gray]

Had a sweet little paying gig come thru my shop. Some simple turning down of hex nuts. they took about eight minutes each. The money per unit is great, but sadly the customer only needed four units.