Trying Some Finer Details

Feeling somewhat confident with my feeds/speeds so far, I decided to try a design that is a little complicated.  Back to google, I found this .svg design -

That picture is actually the output from VCarve Pro's simulated tool path.  Prior to this simulation I had VCP set to use a 1/8" bit (same one in this entry).  With that bit, when I ran the simulation, I quickly found that most of the flower stems would not carve.  This was because they are smaller than the bit size.  Digging around in my bit stash again I found that I had a 1/16" version of the same bit.  After selecting it I re-ran the simulation and got he results shown above.  

The last two runs I did in my prior blog entry were at 100 and 75 imp.  Acknowledging that faster is more desirable, I was curious as to how slow I could go before I encountered issues.  So I decided to dial back even more to 50 imp.  Final settings:

• Dewalt router speed set to 1 (always is)
• DOC set to material thickness for one cut pass
• Feed set to 50 imp
• 1/16" up cut spiral 2 flute end mill

For my previous carves I had created a jig to help hold the record in place.  Up until this run the records had fit in the jig just fine.  This time, however, the record was slightly lager and did not completely set in the jig.  I really did not feel like re-jigging my jig so I decided to fudge things.  Since the design was on the left side of the record I would let the right side ride high.  This also resulted in the bottom ridding high also but I was game to see what was going to happen.

Well, what happened was unreputable proof that the material should be material should be securely secured (huh?) to the work surface with no vertical movement allowed.  As for the carve itself, it went very well.  I was extremely happy with the level of detail (e.g. thin pointy pieces of the record that did not break off) but that happened only where the material was not allowed to move up and down.

There were places where the material was not secured well and that resulted in small pointy pieces being broken or bent.  There was even on case where it broke between a cutout and the outside edge of the record.  

Overall, I was happy with the results.  I know what the problems are and feel confident moving in to my carve.

Fine Tuning The Musical Notes

As a follow-up to the My First Carve entry, I decided to ditch the v-bit.  When I bought my X-Carve I also purchased a variety of bits to go along with it.  While digging through my stash I realized I had this one -



Its a 1/8" single flute up cut end mill and is noted as being designed for soft plastics.  I really don't know if a vinyl record is considered hard or soft but I figured I would give it a try.

My first carve consisted of 3 separate musical note images.  I decided I would do my next test with only one of those items which would allow me to reuse the same record.

Instead of running at 200 I decided to dial back to 100 imp.  The first carve also had a DOC of .015 which resulted in many passes.  I got aggressive and decided to try the carve in one pass so I set my DOC to the material thickness and generated the gcode.

Since I was reusing the same record, I placed it so that that one musical note item would carve in an available spot on the record.  This time I made a greater effort of securing the material - I covered both the waste board and the back of the record with blue painters table and then used super glue to to adhere them together.

This run turned out MUCH better.  It cut through the material in the single pass without issue and left nice clean cut lines (my previous run of 200 imp caused rough gagged lines and non-circular curves).  There were a few spots where the shavings were stuck to the record but those came off with a slight brush of my finger (being v-e-r-y careful not to cut myself on the sharp edge).

This test carve was a success.  The slower 100 imp did not cause any melting and nothing was blobbed on the bit and I got smooth cuts.  Out of curiosity I did the same run except at 75 imp and got matching results.

My First Carve

As mentioned in the Purpose Of This Site page, my first carve was based on a forum post where GlennMDutcher stated what he used:

• Dewalt set to 6
• 200 IPM
• .015 DOC
• 11 degree bit

I did a quick search on the internet and found an .stl file I could start with.  I use VCarve Pro so I opened it up, set some material dimensions, imported the .stl, and generated some carve gcode.

Except for setting my Dewalt to a speed of 6 (I keep mine at 1 which could have been the reason for my poor results) I used all of his values for carve.  Here are my results -

In the first image you can see evidence of melting.  The bit had quickly built up a blob of vinyl, which was just above the surface of the material, and as it was spinning created so much heat that it caused the top-side melted edges.  Before the router moved to the second item to carve I paused the process and knocked the blob off with a pencil.  After restarting it never blobbed again.  But, as can be seen in the other 2 pictures, there was a very rough cut with some pieces being broken off. 

I did a poor job of securing the material and it was bouncing around quite a bit while the router was doing its thing.  Although I believe that bouncing contributed to pieces breaking, I do feel the aggressive speed of the router's movement also played a role.

Plans for next carve - try a different bit, secure the material better, and slow things down.

First Blog Post

Just to kick things off...be sure to read about the Purpose Of This Site to get a feel for what is here.