Using Contact Paper and 2F Fish Tail Upcut (1/16")

Projects
1

I have a project where I would like to do the following on my X-Carve:

  1. Stain a piece of Poplar using Minwax Gel Stain.

  2. Once the stain is dry I plan to use Con-Tact Creative Covering Contact Paper https://hdsupplysolutions.com/shop/p/18-x-20-con-tact-creative-covering-contact-paper---white-p132387?gclid=CKDjpsOutMoCFYQ1aQodsd8BaA
    as a masking layer.

3a. Use a 2F Fish Tail Upcut (1/16") to cut my design outline through both the contact paper and barely into the poplar.

3b. Remove the now cut out “stencil shape” and cut the remaining depth.

  1. Paint the exposed design with black paint.

  2. Remove the contact paper and apply a clear coat to the entire piece.

My question is this: Will the end mill be able to cut through the contact paper without breaking? Many people including the description for the contact paper sold on the Inventables store recommends using a V-Bit to carve the design. Should I use a V-Bit to carve step 3a and then switch to the 1/16" end mill? What feeds and speeds should I use?

2

@ChristopherElledge

Yeah I dont see any problem with doing that I am curious why dont you just cut to your desired depth with the dorst cut I dont think you need to stop and remove the cut out piece it will just remove itself

My question for you is how thick is this paper? Is it just paper with adhesive backing?

I would worry that the strength of the adhesive could tear out wood fibers might want to look into using just simple blue masking tape

And for the .0625" bit I would to
20inch/min and .03125 depth of cut in the poplar

Also you might look into getting a 2 flute straight bit instead of the upcut sprial or even a downcut sprial might work better

The upcut sprial will work but it might mess up the finish that you hve already applied around the edges

3

I don’t think the end mill should not have any problem with the paper. Maybe if the glue reside built up on the bit it might case problems. But I don’t think regular contact paper is that sticky.
If it is then you may want to consider a V or Spiral bit.

As always do a test run with some scrap to see how well it works.
If it works really well you might be able to mill out the letters completely in the first pass, eliminating the “Stencil” phase.

Another concern would be the bit lifting the paper up at the edges of the cut. If that happens you might want to consider a Downcut bit of some kind.
Regular (Up cut) bits pull the chips up, this can also pull up and tear veneers, tapes and other thin coatings.
Down cut bits push the chips down. Which is good for venires and coatings but can have problems in high chip load situations.

4

Thanks for the tips. I decided to go ahead and prepare a scrap piece of poplar with the same stain treatment and now will be able to test each step before actually using it on the real piece. I will order some downcut bits for the future, but hopefully being able to test on the scrap piece will allow me to fix any issues I run into along the way.

1 Like
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I had absolutely no luck using contact paper as a mask. First and foremost, it didn’t adhere well and pulled up when being cut. And what did stay down did not cut cleanly. Could have been my feeds and speeds settings, or my v-bit not being sharp enough, but I’m not really sure. I know I’ve seen people use it before. If you don’t get results with contact paper, spend the money and get yourself a roll of Orafol Oramask 813. It is what they call a “rigid” paint mask. It adheres better than contact paper, but doesn’t tear your material when you remove it, nor does it leave a residue. It is specifically designed as a paint mask. It cuts beautifully with the right bit. My 90-degree amana v-bit leaves an amazing edge. My 60-degree timberline v-bit was so-so. I think if you are using straight bits, a downspiral may keep the edge of the masking cleaner. Let us know how your test goes.

7

Differences between upcut and down cut using contact paper:

DOWNCUT (perfect):

IMAG1079.jpg2688Ă—1520 978 KB

UPCUT (disaster):

IMAG1072.jpg2688Ă—1520 996 KB

4 Likes
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This is super helpful thank you!

9

Thank you for sharing that. I have had the exact same experience with the upcut bit with contact paper.

Do you have a good suggestion of a source for downcut bits? I am having difficulty finding a selection of downcut bits.

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I get my bits on amazon. search for cnc mill downcut or downspiral. Look at one of your bits to compare to make sure the bit pictured is down spiral. There is also something called compression which is down spiral at the tip and upcut the rest of the way. But I have not found a .125" compression. Only .25"