Machinists Corner

[Duuuuuuuude]

Originally Posted by xjman

Yeah that works really well for centering if you are cutting from a completely raw part, but if you buy something already turned to the diameter you are looking for not so much.

You can still find center with some calipers.

[CREEPERBOB]

It is still easier to "touch off" with a tool like you fabbed, on a part then subtract 1/2 of the tool used and then half of the work O.D. to find center. This works on a lathe as well as a mill.

Originally Posted by Duuuuuuuude

You can still find center with some calipers.

[landon4]

Originally Posted by rlockwood

if you're doing production work, and perhaps someone else is footing the bill for equipment... invest in a coaxial indicator. No more mirror, just set the spindle running at about 100rpm, and jog around until there is no more movement indicated on the gage. Its much, much faster.

Well I don't do production work the parts I work on are downhole exploratory tool for baker Hughes and they average between 6-9 weeks just on a vertical mill not including all the other processes they go through, but I do have a co-ax indicator for sweeping in bores as a co-ax will not work on our setups when the parts are blanks, but they would once we put some bores in them here's a few pics of our work.

[landon4]

Also just to note all those parts I run in the previous pics are 6al titanium with a dia of 4.75" and range from about 6-12' for the longest part which has 5 operations on a vertical mill.

[4xFord]

Originally Posted by landon4

Also just to note all those parts I run in the previous pics are 6al titanium with a dia of 4.75" and range from about 6-12' for the longest part which has 5 operations on a vertical mill.

And also note that I saw the CNC working over said 12ft Ti pieces and it was unreal.

[landon4]

Yeah that 12' piece of ti is a $130,000 tool when it is done.

[Duuuuuuuude]

Originally Posted by CREEPERBOB

It is still easier to "touch off" with a tool like you fabbed, on a part then subtract 1/2 of the tool used and then half of the work O.D. to find center. This works on a lathe as well as a mill.

True, but my method is a little different, and still uses the tool I made.

Also, that is a damn impressive chunk of metal up there! ^^^^^^^

[CREEPERBOB]

No kidding, and Titanium to boot. Did you notice the roller's beside it to steady it during working it?
Titanium has a beautiful color to it, I'm fixin' to make some links out of it for my super.

Originally Posted by Duuuuuuuude

True, but my method is a little different, and still uses the tool I made.

Also, that is a damn impressive chunk of metal up there! ^^^^^^^

[rlockwood]

Originally Posted by landon4

Well I don't do production work the parts I work on are downhole exploratory tool for baker Hughes and they average between 6-9 weeks just on a vertical mill not including all the other processes they go through, but I do have a co-ax indicator for sweeping in bores as a co-ax will not work on our setups when the parts are blanks, but they would once we put some bores in them here's a few pics of our work.

Those look fun.

[C*H*U*D]

Originally Posted by rlockwood

Those look fun.

Those look big!

[xjman]

Nothing I cut really looks nifty. Just a tube with holes in it, sometimes I mill a clover shaped profile in one of the faces. Do you guys work at places that allow you to work on "government jobs" or production stuff?

Where I am if you tried to work on your own project you would be in a nice little bit of trouble.

[rlockwood]

Originally Posted by xjman

Nothing I cut really looks nifty. Just a tube with holes in it, sometimes I mill a clover shaped profile in one of the faces. Do you guys work at places that allow you to work on "government jobs" or production stuff?

Where I am if you tried to work on your own project you would be in a nice little bit of trouble.

Provided its not on the clock, its good to go.. But its definately a "take extra care not to damage anything" scenario.

My dad has a small machine shop with 4 VMC's, and I used to do all of my after-hours work there. Eventually I got so used to the organization and machine centers here that it became cumbersome to do anything at his place..

[landon4]

I can usually mess around with my projects at lunchtime and break and there ok with that. I make some ti links for myself and a couple buddies and I've turned down axle tubes and a few other little things. Here's a couple pics of some other parts one is a blank before any work all it has done is the gun drills going through the part from end to end, another is some pretty cool pocket work and then a couple bores with some grooves and chamfers in them.

[mtdriver]

Those are impressive landon! Compared to what I do it looks quite intimidating.

I run a Mazak Nexus 700D-II VMC and a Nexus 250 Quick Turn lathe. The lathe runs nothing but production for our own products, maybe a customer job once a month. The VMC runs a little of both. Mostly basic stuff on each of em. We dont have any Cad Cam software so keeping customer parts simple earns us money. Nobody would pay what we would have to charge to program on the controller, even though theyre conversational and do a lot of stuff for you, still takes time to do anything complex.

We also have an older Mazak Super Turbo MK II laser that I run. That cuts 70% of our own parts and 30% customer jobs depending on how sales are doing.

The owner of the shop could care less what I use his machines for, as long as I dont break them and show him what I make. So far I have never had to pay for any of the things Ive made at work. He thinks my 'toy trucks' are awesome.

[xjman]

That is really nice work. What do you have mounting it besides the rollers?

I'd post up some pictures of what I make but I don't really feel like having the military beating down my door because I posted a picture. Simply put I make drive couplings for turbine powered equipment. Generators, pumps, etcetera. Some of the parts I make will exceed 100k rpm.

Because of that the tolerances are wicked tight .0005 on hole size and .001 on location.

On a side note kenemetal boring bars won't hold a half thousand tolerance for anything.

Sent from my Galaxy Nexus using Tapatalk 2

[landon4]

Thanks guys it is nice work, especially to run as some tools have 3-4 hour cycle times. As far as holding the parts we have a tail stock at one end, and the part slides through a 4th axis chuck like a rotary table I will try to get some pics of it when I go back to work. We deal with some close tolerances the bore in the pics are +.002 -.000 and we have a lot of reamed holes that are+.0005-.000 but a lot of it is +\-.005 we just have to deal with lots of cutter comp tools and h offsets. Then theres the always double check because a mistake in one of the bores with one of the grooving tools could be very costly to fix easily getting around the $10,000 mark as sometimes they would have to e-beam weld the parts.

[rlockwood]

Originally Posted by xjman

That is really nice work. What do you have mounting it besides the rollers?

I'd post up some pictures of what I make but I don't really feel like having the military beating down my door because I posted a picture. Simply put I make drive couplings for turbine powered equipment. Generators, pumps, etcetera. Some of the parts I make will exceed 100k rpm.

Because of that the tolerances are wicked tight .0005 on hole size and .001 on location.

On a side note kenemetal boring bars won't hold a half thousand tolerance for anything.

Sent from my Galaxy Nexus using Tapatalk 2

we have alot of +/-.0002 bores, and have good luck leaving them a few tenths under, and honing them to size..

[landon4]

Yeah we try to keep our bores about 3 tenths in and we usually don't have any trouble holding that and then our deburr dept. will polish them to nominal size.

[OllllO Fanatic]

Just out of curiousity how easy... or hard is it to build a small cnc setup for my self. I have always thought it looked pretty cool, but never knew a lot about it. If I have understood correctly I would need to learn a cad type of program. And if so is solid works one of them? And how expensive is it to first off build a setup, and two to buy the block of what ever metal and turn it into something cool? Sorry if these are dumb questions, jsut want to learn. I would want to create rc parts, large and small if it was reasonable. If not is there any one who would or could help me with a project?

[rlockwood]

Originally Posted by OllllO Fanatic

Just out of curiousity how easy... or hard is it to build a small cnc setup for my self. I have always thought it looked pretty cool, but never knew a lot about it. If I have understood correctly I would need to learn a cad type of program. And if so is solid works one of them? And how expensive is it to first off build a setup, and two to buy the block of what ever metal and turn it into something cool? Sorry if these are dumb questions, jsut want to learn. I would want to create rc parts, large and small if it was reasonable. If not is there any one who would or could help me with a project?

Its a topic that requires a LOT of research, as the options are pretty endless. Benchtop mills (taig, sherline, grizzly, sieg, etc) are typically a good fit for R/C stuff. I believe a "CNC Ready" taig can be had for under $2000. DIY Routers are another good route (pardon the pun) and open up your options outside of R/C stuff, as their work area is typically much larger.. Check out cnczone and practicalmachinist.. both are good resources for getting started.

Also, dont expect to simply make something in solidworks and have the machine cut it out for you. Its not a 3D printer, there is more to it than that