Little CNC lathe

[Tin Falcon]

well after taking the needed Sunday afternoon nap I got some more done. I made the t-nuts then enlisted the assistance of the apprentice and we did the tooling plate well sort of it is on and will function a couple of holes are misplaced and I t will likely need some more later. the A2Z tool post borrowed from the grizzly is now mounted. the chuck is a bit stiff I think old sticky oil so need to open that up to clean .
And of coarse there is still the spindle sensor and spindle control to deal with later. but the next thing on the agenda is program and run a part or two.
Tin

 

[vlmarshall]

congrats! Tooling plate, eh? Are you using pallet tooling?


Which spindle control are you using?

 

[Tin Falcon]

well I needed some way of attaching a tool post I guess I could have made a plug or something to go in the hole for the accessory compound that I do not have . otherwise it just has 1/4' wide T slots . the A2Z I have mount to the little grizzly with a 10mm bolt so I made a plate that I could tap for the 10 mm bolt. then mounted the qctp. eventually I will ad other holes to move the tool post if needed and at least put a hole for a rear tool post. also I needed to raise the tool post
As far as spindle control that is problem down the road a bit. The motor is a 110 DC that has a rectifier bridge to convert wall AC to dc that is it. So I am thinking I can use either hook up the PWM from a tread mill or used share the control board off the mill. The G540 has built in spindle control capability just need to wire it up. may need a relay also not sure as the mill has a built in switch in the variable resistor.
tin

 

[Tin Falcon]

here is a photo

of the current status
Tin

 

[Tin Falcon]

yesterday did some initial trails.

well yesterday tried some basic turning under cnc control.
After some software adjustments and a little operator headspace adjustment. thew a few chips.
I also discovered that to hold a mere 1/2 piece of round stock the steel part of the two piece jaws interfere with the spindle nose threads bottom line is the factory chuck does not hold a peice of 1/2 stock . so am in the process of making another set of soft jaws that are a bit longer . I wated to make a set anyway but did not want to be forced into it. Oh well.
Tin

 

[vlmarshall]

Ah that's too bad. :-\

 

[1hand]

*Just wired pins 6-9 for the motor wires.[

Ok awake now I think. I realized while taking my shower, last night very late, that the wiring just pins 6-9 effectively eliminates the current set resitor that I built into the male db-9 connector attached to the project box. SOOO make a new cable is first order of business before going forward. I did notice that the z axis motor did not seem to be running as smooth as the x. Well no magic smoke released. another duh.
Tin

Yeah, maybe I should pay a bit more attention when I read other peoples posts and threads. I even read this before I ordered wire, and the light bulb still didn't come on. :wall:

 

[Tin Falcon]

not much going on this weekend . Should be getting outside stuff done. so a trip to the hardware store to pick up fasteners for a fix up job.Also a set of #61 -80 drill bits. Then to walmart to get my glasses fixed. Then in a point of weakness broke down and bought one of these. It is a XBox 360 controler

I have been thinking about these for a while but kept holidng of on spending the bucks.
this will be used for a Mach 3 jog pendant. I installed it and got it running . now just need to decide how I want to assigned all those buttons. I also need to fgure aout if it can be set up differently for the lathe and mill or I need a one configuration for both machine thing. I guess there would be advantages and disadvantages either way.
The plug in was downloaded from the Mach 3 site

Tin

 

[Tin Falcon]

Well figured about time for another update. Things a bit crazy at work the last few weeks . and having to deal with some home and minor health issues as well.
The xbox controller was easy to configure and there are lots of ways to configure/customize the buttons to run mach. Had some fun moving the tool around with the joy sticks. I need to take time and tune up true up the soft jaws I made.
the x-box controller is probably not the best pendant for mach 3 but they are readily available and reasonably priced. If you are luck you may even be able to get one at a yard sale or flea market.
Tin

 

[90LX_Notch]

Geez Tin, that must be some hardware store to carry a #61 -80 drill set. I wish something like that was around here.

 

[Tin Falcon]

I am fortunate there are still a few good ones around here.
Tin

 

[skeeter]

Hi, Tin . I was curious how your cnc project was coming along?
Best Regards
Skeeter ;D

 

[Tin Falcon]

Skeeter:
the cnc build is mostly complete the little machine moves under computer control or the control of the x-box 360 controller. There is more work to be done in the form of a rpm pickup this will allow threading and constant velocity mode. I may also hook up spindle control and eventually coolant control. Right now I need to work out the kinks in the chuck so it will run true. That and adjust operator head space. I have run a cnc lathe for a year full time so I should be familiar right. But I have never really programed one. I am a seat of the pants manual machinist that goes by feel . yes there is theory behind it but i am used to chucking a piece in the lathe turn on the spindle crank it up til it sounds right then feed in by hand and swish off the chips. if it does not sound right i adjust on the fly.The only way to learn to program is to do it but there is a fear that i will make a mistake and crash something. So I need to take it step by step and learn to machine by the numbers. I downloaded a program that should help me and others to learn g-code and machining by the numbers it is called AutoEditNC 3.0 it is a free tutorial designed for high School trade school ad college students. it teaches and debugs g-code to filter out the mistakes before it goes to the machine. There is also a companion program . Mfg Calc to help with speeds and feeds. link here http://www.betatechnical.com/autonc.htmAnd I have though about getting the license for cambam.
A good athlete say a baseball player can place the ball anywhere he desires in the infield with a good throw. And a physics student or engineer can do the math that calculates the force and trajectory to place that same ball on target. That is the same thing, or not. While we are talking the same task and result we are also talking two completely different skill sets.
So just need to move from this computer to the other one an press on.
Tin

 

[skeeter]

Thanks, Tin. Sounds like our machining experience is similar. I haven't run a cnc lathe but have run cnc verticle machining centers Mazaks. Done same thing by sight and sound. All of my machining has been manual machines even edm machines. I have also programed and run cnc edm machines sinker type. I think if a person has some manual machining experience they make the best cnc operators my opinion. Have you ever used poly crystaline diamond tools in a lathe ? The surface finish is very nice with these tools. They WILL NOT take intermited cuts tho. Maybe you could use some machinable wax to get feel of your lathe first ?
skeeter ;D

 

[Tin Falcon]

Have never used diamond tools . I know they are great for consistent finishing but expensive. I have definitely considered the machinable wax but have not taken the plunge. As apprehensive as I am to jump into cnc I know my manual background will serve me well. I have a bit of college behind me as well almost 3 associates degrees and more credits than needed for a bachelors just not the right squares filled in the score card.
Tin

 

[skeeter]

Hi, Tin . I have got some collage too almost an associates degree. Maybe more if or when I test out of some other subjects. The majority of my experience has been through hands on work. I have had the honor of working with some old school machinists, toolmakers, engineers, welders, ECT. Still got a lot to learn .
Best Regards
Terry ; ;D

 

[Tin Falcon]

Well finally got the soft jaw issue sorted out . Bored a step to hold a bushing while holding a button cell in the internal bore. then held the bushing in the step and bored through and true. I used the Mach 3 wizard to generate the g code. So nothing hard or fancy . I do need to get used to speeds and feeds by the numbers . Just so used to going by feel maybe I can move forward now. still a lot to learn . But first chips are a start and no major crashes.

And another lesson learned. the motors were getting a bit "warm" quick touch test. I was a little concerned this was not a long machining session. Sooo a little research I find my motors are rated at a 80 degee c temp rise (144f) and the manual warns do not touch energized motors they can burn. I did not realize these puppies get that hot!! my shop is about 75 plus 140 looks like i could boil water.
Tin

 

[willburrrr2003]

Tin,

I had a problem with my motors getting too hot a couple weeks ago, found that my motor current was set to high. Also found that the setup for my controller recommends only setting current to 70% of calculated max current. I did this and the motors have run a lot cooler since then, and I have not had any issues also, does your driver have an idle current reduction setting? I know Mach3 has a function built in for controlling this if your hardware will support it.

I also know what you mean about having to learn on the fly how to setup, and program a cnc lathe, still learning to do the same here and way different than just being an operator... only had one major crash into the spindle, and thank god my drive belt was loos or I would have broken something Have had a couple instances where I issued the wrong command and trashed a practice part too :big: I'll chock that up to operator head space and timing hehe



Regards,


Will R.

 

[Tin Falcon]

Like I said in my x2 mill thread this thread is like a Star Trek series a continuing mission to explore . my current project, or more appropriately b sub project is adding a an optical spindle sensor to the little lathe.
I need to start taking photos . it is more work than I anticipated but if I intend to thread on the lathe I need a spindle sensor.
Tin

 

[DICKEYBIRD]

Tin,

Just found this thread again, thanks. I went through a similar process with my little hodge-podge CNC lathe. Lotsa fun!

Do you already have your speed sensor/indexer? I got one of these from Arturo and it works great. Cheap & plays well with Mach! I'm saving my pennies for one of his speed controller boards so I can control the KBIC-120/treadmill motor via Mach.

http://www.cnc4pc.com/Store/osc/product_info.php?cPath=25&products_id=129