Hey!
I am playing around with my machine and wanted to try some 3d carving.
Everyone is talking about ball nose bits, so I ordered one.
But now I am really confused, because most people talk about 1/8" ball nose bits.
Mine looks like this:
So my questions are:
Is this a suitable ballnose bit for this project?
I am trying to carve from a 2" x 2" pine piece of wood.
Does the finishing pass really take 15 minutes at 150 ipm @ 16.000 rpm?
Can I use the same bit for roughing pass as well? Just checked again. When I use a 1/8 bit roughing takes 5 minutes.
If the cutting end of the bit is flat then it is an End Mill, if the cutting end is rounded then it is a ball nose, When someone refers to a 1/8 ball nose it is a tool with a 1/8 inch cutting diameter and a rounded end.
A 1/8 Endmill and a 1/8 ball nose both have a 1/8 inch cutting diameter.
Here is a good explanation of the different cutting tools
Seems to look like a ballnose from your pic. I use mainly .25" and .125" ballnose bits for most of my creative work, like you’ve shown above. if yours has a .04" width, that’s… really small, 1/25"? Looks bigger than that in the pic to me.
To answer your questions:
Is this a suitable ballnose bit for this project? : Yes
I am trying to carve from a 2" x 2" pine piece of wood. Sounds good.
Does the finishing pass really take 15 minutes at 150 ipm @ 16.000 rpm? : Maybe? Entirely depends on your stepover and bit size. To get a nice finish I usually set mine to a 10% bit width for stepover. For a .125" bit, that will take twice as long as a .25" bit.
Can I use the same bit for roughing pass as well? Just checked again. When I use a 1/8 bit roughing takes 5 minutes. : Yes, I often use the same bit for both passes. But I’ll also use a .25" endmill (flat tip) for the rough, then switch out to a .125" ballnose for the finish.
The link is pointing to a tapered bit. That will do a great job for your detail pass and a horrible job for the rough pass.
If you are using a tapered bit you need to be sure you have told the CAM software that you are using a tapered tool, it works much differently than an endmill or ball nose.
Looks like a tapered bit. The tapered bit is preferred by some because you get a smaller tip but a stronger bit overall.
As Allen said, you need to tell your software you are using a tapered bit. In that link, there is a column in the table that says the taper degree per side. You’ll need that for your CAM software.
Ah thank you so much. Think I slowly got it. I even ordered a ball nose before, but I cannot find it anymore
Just ordered 6 more. Even found the settings for the tapered bit now.
@AK_Eric why do you do the roughing pass slower than the finishing pass? In theory I would have thought it should be the other way around
nononono : You need to tell your CAM software the exact bit size, or chaos will ensue. that’s a super tiny bit, completely overkill for something like this, the cut would take forever.
Per what AsslenMassey said: Rough passes remove large quantities of wood, thus, you generally need to cut slower so as to not stress the machine\snap bits. Finish passes only remove a tiny amount per pass, so you can run it much faster.
Fore example, on my rough-passes, I used a .25" endmill (flat tip), with a .125" stepover (.5 bit width) and .125" cut depth (.5 bit width).
For finish, I’ll use a .125" ballnose (round tip) with a .0125" stepover (10% bit width) : I’m removing far less material, so I can run it a lot faster.
However, the values I’ve listed I’ve spent hours\days tuning per wood type, per bit-type, on my machine. The value you use could be very different.
Thank you for all your help.
By this few answers I already learned so much!
So although it didn’t come out correct…here is what I just did:
Roughing pass took around 10 minutes (1/8" end mill).
Finishing pass took around 7 minutes, but I stopped after 2 (1mm tapered ball nose )
Unfortunately my finishing was moved a little bit (by around 1 cm).
But at the top right you can at least see that he made some really nice smooth edges.
I am really happy with the result. Unfortunately I cannot try it again right now, because its half past ten here and I have to cut in a small house where several people live
Have to try it again tomorrow.
Thank you so much for all your help!
Due to the default lower max speed rate for Z vs X/Y, and also acceleration value is less = any contouring Z-motion will take longer compared to pure X/Y.
Stepover is also set lower for finishing pass.
Yep: I doubled my z to 40ipm in the firmware, really helped my times out. I tried going faster, but the stepper started skipping on the retracts, causing progressively deeper cuts. Need more power!
Hm usually I carved small stuff at 30 ipm and 16k rpm.
Thought this was so fast that I should turn the rpm a little bit higher.
I do not have an x-carve. I have an ooznest ox from openbuilds and use a Kress 1050 FM-E.
But I fell in love with the community and the easel software.
Please don’t ban me
