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Britannicus1
12-03-2020, 01:03 PM
I've had a go at engraving a plaque and I'm quite happy with the result - EXCEPT - I want to make more contrast between my engraved image and the plain plywood I cut this on.

I've tried a few experiments

1/ I first tried cutting with a masking film and then spray painted, but the pain bled along the groove

2/ Next I tried using a paint line along grooves - messy and unsatisfactory

3/ I did try spraying the whole surface black an cutting through - but this gave me a light line against dark and I'm looking for the reverse really

What treatments do you use to get a pleasing finish on your CNC work - I'm planning on working on light oak at the moment . any tips on how to get multiple colours into the finished product ?

27567

Voicecoil
12-03-2020, 04:43 PM
I

3/ I did try spraying the whole surface black an cutting through - but this gave me a light line against dark and I'm looking for the reverse really

27567

How about lightly spraying everything black, then skimming/sanding the surface to return the uncarved bits to the original colour? Alternatively laminate some thin light oak onto some dyed wood or dark coloured Valchromat and carve through.

NordicCnc
12-03-2020, 05:15 PM
I usually first surface the material, then I engrave 0.5-1mm too deep. After that I paint every thing, byt I try to focus on the engraved part. When the paint has dried I surface the material again, removing the 0.5-1mm. This will give you a nice contour to the engraved part.

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johngoodrich
12-03-2020, 08:07 PM
if you engrave the part using a mask, seal the engraved area with a shellac sealer first before painting it and it wont bleed

Britannicus1
13-03-2020, 10:52 AM
cheers sounds like good advice

Britannicus1
16-03-2020, 12:33 PM
if you engrave the part using a mask, seal the engraved area with a shellac sealer first before painting it and it wont bleed

Excellent advice - thanks a lot - made a world of difference - a little surface blurring, but a light sand and a coat of varnish will soon fax that

Before

27617

After

27618

Mickey_Smith
20-11-2020, 09:10 PM
Holy Cow!!
I love your work. Keep going

I normally prefer solid wood rather than plywood. There are numerous reasons for this. However, for newbies, plywood is good for practice. However, the plywood is engineered wood (https://sawauthority.com/plywood-vs-solid-wood/) and is made up of layers of sheets, due to which the grains change from layer to layer, making it splinter. For your next CNC work, Oak is great.

Don't forget to give a sealer to the bare wood. In the end, some boiled linseed oil or paste wax is great for finishing.
Make sure to apply the lighter color first than, the darker shade.
First, try painting in a newspaper and then go for a final paint on the wood.