Inlay Issue

Tried doing a test inlay tonight with a 1/16" bit … set up the pocket as a hole (pocket) and the inlay as a part in Estlcam… ran at a pretty slow speed… pocket is too small… used the same bit for both… not sure what I am doing wrong.

My best guess would be that your bit isn’t exactly 1/16th. You may want to measure it precisely to make sure.

Could also be deflexion of the Z axis.

Could also be because your CNC is not perfectly squared and you made your parts at different places of the bed.

Also, you didn’t precise what tolerance you accounted for. You need to make the inlay a bit smaller than the pocket in any case,

How much of a difference did you get exactly?

I will need to check the bit. I am just trying to learn - trial and error…

I didn’t realize I needed a tolerance or to make the inlay smaller.

What is the best method for doing something like this?

I would just scale down the inlay or scale up the pocket by a few percent, should do the trick

I checked the bit I used and it measures 1.65mm which I don’t think matches what I had in Estlcam. I’m not sure where I should start to toubleshoot … scaling or modifying the tool measurement in Estlcam or both. I just ran a 1.5" square pocket and that is with me adjusting the bit to 1.65mm as measured with my digital calipers. The pocket only measures 1.489 so I am not exactly sure what I am doing wrong… should I be adding some finishing parameters?

Could an improper step over cause this issue ?

I don’t have all of the functions of Estlcam down … looking at it the tool is set up as in the screen print.

Maybe check your spindle to make sure it’s square to the table.
I set my endmill shape to 180 degrees for regular end mills.

So I made a change to the end mill to be 180 degrees and the square is still measuring 1.48…

I will try the other test you suggest but not sure how I will adjust if its not square with the table. I have the 500w Amazon spindle that I am using. So I’ll have to make a remix of that thing for it to fit.

Are my expectations wrong… if I pocket a 2" hole it should be 2" right?

On that thingiverse thing… how do you use it? You certainly do not turn on the spindle do you?

If you are going for super accurate, are you doing a roughing and finishing pass? With just a roughing pass you get the bit moving around from all the torque if you leave a little material and come back with a finishing pass you should get tighter tolerances.

You do need to leave some sort of gap though. How big depends on you end use and your adhesive.

I am merely trying to learn how to do a simple inlay. I have not set anything for a finishing path. Should I be?

Sorry but this stuff is so greek to me I am having a hard time “getting it”.

Correct, do not power the trammel bar up. Manually turn it, if it touches the table and you turn it 180 degrees and does not touch the spindle is crooked. Some paper shims is all it should take. Check it along the X and Y. A finish pass would probably help as well.

I completely understand, I’m here to help. Adjust your bit diameter, use .5-.75mm finishing pass and see if anything is better.

You should be using a finishing pass, almost always, unless dimensions do not matter very much.

In my 2.5D tutorial you will see I use finishing passes there (they are easier to do now than the 2 path method I used in there).

So something like this?

So I assume it will do the rough cut and then go back and do this .75 finishing work correct?

Does it pause for any user input, etc?

If you are using a 1/16 you need to half that finishing pass.

It is just another tool pas, no pause.

I have a video of it. You might really want to work though my 2.5D and see how I cut things. It really might clarify things for you. It has everything except tool changes.

I’ll check out the 2.5 —

When you say have that finishing path… meaning half of .75 ?

One last question… in Estlcam when the gcode is generated it looks like this at the top…

;Project 1.5 inch square
;Created by Estlcam version 10 build 10.017
;Machining time about 00:28:20 hours

M03 S24000
G00 X0.0000 Y0.0000 Z0.0000 F2100
G00 Z2.0000 F480

I always have to edit the 3rd line changing G00 to G92… is there anyway in Estlcam to just have it generate G92 all of the time. will save me several steps in prepping the file for the SD card.

Well, just finished this past round with the finishing path at .75 and I am now even more confused…

the x dimension is 1.47 and the y dimension is 1.45. where as before I added the finishing path it was square at 1.48

Why would you edit that. g0=go to these coordinates, meaning if you are not there go there. G92 is reset coordinates. If you want that you should reset the arduino.

Your cut is now undersized pretty equally, maybe you should put the bit back to 1/16". By making it larger in the CAM you are making a smaller cut, to truly test that you would do an inside and outside cut, one will get too big, one will get to small.

Good luck, I will be back this evening.

Depending on what you are doing you will need to use the overcut feature on the corners or manually trim them with a chisel or something.

The measurements are off all the way around… not 2" so it’s not a corner issue.

It looks like it could be as simple as a path location issue (outside, on, or inside contour cut on the inlay part).

Are you selecting outside border of the inlay piece? and the inside of the line for the pocket?

For the piece that gets placed inside, since it is too large, you could tell it to cut on the line (or even inside) to bring that cut in closer to the dimensions of the pocket.