I am trying to engrave/carve “wax seals” out of aluminum. I have been all over the forum for info, and have tried to run a few cuts with little success.
I am using Easel Pro. (Haven’t pulled the trigger on V-Carve Pro yet).
I am using a vacuum (not the shoe) to draw away chips and cool the bit.
I am using 30deg v-bits that I found on amazon.
“Titanium Coated Carbide PCB Engraving CNC Bit Router Tool 30 Degree 0.1mm Tip(J3.3001Tix10) by Autek”
These are the two settings I tried, pulling them from a few different posts.
The total depth of cut is supposed to be 1.5mm
Router speed 2 (approx 18000rpm)
1st try
Feed rate 500 mm/m 19.7 ipm
Plunge rate 127 mm/m 3 ipm
DOC .127 mm .005 inch
2nd try
Feed rate 700 mm/m 27.6 ipm
Plunge rate 176.2 mm/m 3 ipm
DOC .1 mm .00394 inch
I am not sure if the problem is the bit, or my settings.
Two things that are happening.
There is a burr left on the upper edge. In the picture, I have already sanded the surface, so the burr is gone.
The tip is snapping off, essentially shortening the bit so I don’t get the proper v-shape.
I am using a 30 degree bit, because a 60 deg will not give me enough depth at this size. I have already wrecked two bits, so I figured its time to ask advice. I don’t mind buying a more expensive, better quality bit, I just can’t afford trash them in the first plunge.
Darrin
Hey Darrin, slowing down the router may help prevent burning that tip off. It was counter-intuitive to me at first, but spinning the bit too fast or feeding too slow results in “rubbing” instead of “cutting”, which generates a ton of heat. I keep my router at the lowest speed. I also use some tapping fluid when engraving metal with that kind of bit.
With all that being said, I’ve never been able to keep the perfect point on a bit like that when using it in metal.
Try these:
feedrate 200mm/min
plunge 100mm/min
1mm stepdown
makita at 2
LUBE!!
but at 30deg it’s always going to be extremely finnicky…
also noteworthy, that’s not a true V-bit. As you can see it’s asymmetric. that’s an engraving bit.
They work, but you need to compensate when zeroing.
somewhat discussed here:
https://discuss.inventables.com/t/wavy-lines-when-engraving/36289/7
short version: zero the usual way and then go slightly up. Then re-zero the Z. How much depends on the specific bit. It’s better to start off slightly too high obviously and work your way down until you know the sweet spot for that bit.
Thanks @LukeWilson I will try to slow it down. I got the 18K from the bit information for a similar cutter on the AmanaTools website.
@anon68752607 Thanks for the links. I have read those articles and others. I am aware about the flat spot and the need to adjust the height for absolute accurracy. I didn’t bother with it on this cut, as the slight change in the letter due to the .1mm flat would actually help my design rather than hurt it.
I will try some cutting fluid next go around.
When you say 1mm step down, do you mean a full 1mm depth of cut?
I’ll try again this weekend. Maybe I will have to bite the bullet and try a $50 bit. I’ll have to keep my fingers crossed that I don’t snap the tip first time out.
Darrin
I’ve had good luck carving aluminum with this bit:
Freud 1/2" (Dia.) V Grooving Bit with 1/4" Shank (20-104) https://www.amazon.com/dp/B00004T7DZ/ref=cm_sw_r_cp_apa_i_XtnaBb9WG44JC
$18 is hard to beat
according to my cheat sheet thats how i did it. Because you’re working with a sharp tipped endmill you can go deeper and still have an acceptable engagement area. Maybe start at 0.5 if you’re not confident.
