cnc wood lathe

[javeria]

Hi All,

here is a pic of the wood lathe I have done- while the mechanicals were simple the programing and configuration of the lathe seems a bit too much - though I am still trying

here are the hurdles

1. What would be the right program for CAM lazy turn? JR had fooled sheetcam to work for it any ideas how

2. As the tool and tool profile and the machine co-ordinat is fixed, can I start machining by just referrring to the maachine co-ordinate system, ie., if I home the machine the machine knows that the centre of the lathe is right at a particular distance from the limit switch and then just begin the cutting,

3. where to start - its a bit scary with the 8 inch blade turning at more than 2k rpm.

4. the tail stock end is fixed (it gets hot and digs in)- do i use some thing like a revolving centre on the tail stock?

thanks all in advance -

if need to move to the zone just give me a hint and I will take this thread away, Just that wanted to stay with buddies on the MM forum!

RGDS
IRfan

[Kobus_Joubert]

Hi Irfan, I am green with envy. I run a LIVE CENTRE on mine ...works well.
This setup if ideal for Vectric Aspire. You take any picture of a turned leg...get the profile..set up your workpiece in Aspire and use the 2 rail sweep to put that profile on the workpiece.
I would Zero on the flat piece of the stock. Vectric generate G-Code and Y travel along the piece and X does the profile...just make sure your first cut does not dig deep into the workpiece.....edge it in slowly I would suggest...When you generate cutting path, keep Z=0....only X and y works here

PS I like those rails...looks like they are becoming more and more affordable...what did you pay for them and the sliding bearings/ blocks ?

[javeria]

Hi Kobus, have to get a live centre now, those linear elements were cannibalized from the older cnc router (ball screw)

planning to get the machine configured with the centre axis as part Z zero - hope to get all working this weekend.

will keep you folks updated on this

RGDS
IRfan

[jehayes]

Irfan:

I love it! What an idea! Please show us some turned items when you have them.

Joe #53

[Atifeh]

Hello Irfan,

Since you are fluent with ArtCAM, I will describe the procedure which you are familiar with.

Draw your profile in a CAD programme.
Draw a center axis and mirror the profile.
Draw a rectangle, enveloping the whole profiles.
Close the lower profile with a line.

In ArtCAM, select the lower profile. The rest is self explanatory in the below figure.

11361

There are a few things that should be considered:
Use the Raster tool clearance strategy. You would want the X axis travel paths to be parallel in nature, with the designated stepover.
The stepover is determined by the tool diameter. Actually the tool diameter has nothing to do with the turning process, except that it determines how much Y axis travel (feed) will be considered on each pass, and the offset of the finish path, relative to the actual size of the profile.
The start and finish depths should be zero (actually, you do not have a third axis).

This toolpath will remove chips layer by layer, and in the last and finishing path, it will have a continuous travel to yield a smooth surface. It should be noted that the tool diameter that was selected before will define an offset, half of the tool diameter. You have to adjust it with your saw disk thickness.

The above picture is valid for circular section stocks. However, most of the time the stock has a square cross section. If you touch the X axis, tangent to the face of the bar, chip removal of the four corners will exert excessive pressure that would be disastrous. You should move the envelope rectangle around the patters by 1.414 outwards. In this case the closed profile will differ in shape and will look like this. If you use rectangular stock then the calculations will differ.

11362

In my opinion a 200mm circular saw, is potentially dangerous.
Any miscalculation in the X axis travel vs. the feed amount might bend the disk, or in worst case, if it is carbide tipped, the tips will fly under axial load.

Hope this helps.

[javeria]

Atifeh - thank you - I am using lazy Turn from Artsoft - its free and easy!

do you think using artcam is more advantageous?

AH