2015 POTD Thread Archive

[BillWood]

Started working on a rotary jig - Harold Hall's manual rotary table made me realise that I dont necessarily need a wormscrew/wormwheel - I haven't yet got the skill to make those.

http://www.projectsinmetal.com/a-simple-rotary-table-without-a-worm-drive/



Photos tell the story - should be finished tomorrow.
Bill

Ha !

Famous last words. Other stuff got in the way

See attached picture - Lathe finish is curved circumference nice and smooth - and mill finish is horizontal annulus - a bit ragged.

am getting far better finish on lathe than when using rotary jig on mill.

Is that to be expected ? I guess these things are only meant used for rounding ends and cutting slots and shoulders rather than giving a fine finish on a circular workpiece ?

Anybody ever built and used a similar manual rotary table. (ie this one http://www.projectsinmetal.com/a-simple-rotary-table-without-a-worm-drive/)

I can sort of feel the teeth hitting the workpiece - and I dont get that same feel when using screw feeds on the table - I think that is logical.

You also feel the power of the machine - if you are not careful it can grab the workpiece, if it grabs whilst using the normal screw feeds when the workpiece is clamped to the mill table there is only a finite amount of backlash - if it grabs on a rotary manual feed there can be big jerk before you have it under control.

if you dont concentrate when you start the cut you can find yourself starting or getting caught in an accidental climb cut and that seems to be a bit more serious as the round workpiece basically becomes a wheel driven by a 2hp 4 tooth cog. Could be dangerous. Need to pay close attention and think about directions when starting to cut.

Bill

 

[brino]

Need to learn heaps.

Every journey starts with a step.....and there is no better way to learn.
-brino

 

[Billh50]

Billwood,
If you ever get a chance to add gas to that mig you will find it a lot easier and better welds. Just keep trying different feed rate til you hit the right one. It took me a few tries to hit the right feed rates depending on the amp setting. once I found the right rates I marked the dial area for the different settings. Also I think the gas makes a big difference.

 

[ogberi]

Very first welds at home in the shed

Weldcorp Gasless MIG 100 amp

Need to learn heaps.

Gasless welding tends to spatter quite a bit. That little can of stuff you dip the torch tip into helps keep it from sticking to the copper tip.

I have found that I need to crank up the wire speed to 7-9 on my little flux core welder (lincoln weldpak) to get decent welds. The metal also needs to be clean. A quick once-over with a wire wheel on reasonably clean metal, a flap wheel or sanding disc on crunky stuff.

And practice, practice, practice. Just remember to wear long sleeves to prevent a nasty sunburn.

 

[chevydyl]

You can also buy anti spatter in a spray can for might welding, spray it on the stuff you don't want the spatter to stick to, works ok. By the standards I weld to today, it's tig only, and I mostly weld machined parts, my own and a local machine shops parts that get sent out of state to the end customer

 

[jrstech]

Since moving my mill motor controls to the more ergonomic right side of the mill, I only have one more improvement to make. The motor brake knob. I had to stretch each time I wanted to use it. So I stretched the lever instead!






Much easier to reach and use. I like it!

 

[sanddan]

I like it John. Having the brake handle right next to the for/rev switch makes me nervous. I'd hate to hit the switch when I meant the brake when tightening the drawbar.

Anymore pic's of your mill?

 

[omni_dilletante]

I purchased a South Bend 10R not fully understanding how odd the smaller spindle was. Took some time but found a set of 2A collets and closer on eBay. Problem was that the closer was about 2" too short to work.

Managed to finish the extension today.

First time attempting single point internal threading. Was fortunate the lathe came with a number of boring bars already ground for threading. Anxious about failing to stop the tool in the groove at the back of the thread, but it went pretty good.

Attempted to take the extension off for a picture but it would not budge. I will take that as a good sign.

 

[T Bredehoft]

I keep being reminded that we fix things, use our brains to figure out what needs done, and do it. S0 many people wouldn't know where to start. I applaud your inventiveness. (Not that its unusual here, but is unusual in the real world.)

 

[sanddan]

Did you thread all the way through the extension?

Your fit up looks great by the way. I have yet to try an internal single point thread, lots to learn.