Bit selection, degrees and vendors

1

What type of bits are you using, degrees and vendor.

2

Iā€™ve managed to find one of the Amana kits for a halfway decent deal. I got it from ToolsToday and was amazed by how fast they shipped things out. Normally things from Amazon Prime take a week and a half minimum where I live, and the bits were here in 3 days.

They basically only carry Amana though so youā€™ll want to be careful about breaking them as they are a little more expensive. This is the kit I went with.

3

Hi Michael - it completely depends on what you are cutting. Here is my ā€œshort listā€ of bits I recommend:

From my bits video :

Budget Bits ($):
Small Diameter Bit Set - http://ebay.us/owuT6W
1/32", 2 Flute, Up Cut End Mills - http://ebay.us/A7qv3f
1/16", 2 Flute, Up Cut End Mills - http://ebay.us/nZ5Ccv
1/8", 2 Flute, Up Cut End Mills - http://ebay.us/b4fNK7
1/8", 2 Flute, Down Cut End Mills - http://ebay.us/QHmoDh
1/8", 1 Flute Up Cut End Mill2 - http://ebay.us/et4DGC
1/4", 2 Flute, Up Cut End Mill - http://ebay.us/W48DLF
1/4", 2 Flute, Down Cut End Mill - http://ebay.us/ueEQml

Higher End Bits ($$$):
1/4", 2 Flute, Up Cut End Mill - https://www.toolstoday.com/v-13780-46315-k.html
1/4", 2 Flute, Down Cut End Mill - https://www.toolstoday.com/v-13781-46415-k.html
1/4", 1 Flute, Up Cut End Mill - https://www.toolstoday.com/v-13351-51404-k.html
1/4", 1 Flute, Down Cut End Mill - https://www.toolstoday.com/v-13979-51504-k.html
1/8", 1 Flute Up Cut End Mill - https://www.toolstoday.com/v-13375-51410-k.html
1/8", 1 Flute Down Cut End Mill - https://www.toolstoday.com/v-13977-51510-k.html
1/8", 2 Flute, Up Cut End Mill - https://www.toolstoday.com/v-14140-46127-k.html
1/8", 2 Flute, Down Cut End Mill - https://www.toolstoday.com/v-14107-46227-k.html
60 Degree V-Bit - https://www.toolstoday.com/v-5705-45705.html
90 Degree V-Bit - https://www.toolstoday.com/v-5704-45704.html

Hope it helps.

-Tom

4

Thanks so much for your for your time with this information

5

The list is very helpful; could we dive deeper into ā€˜bestā€™ choices?

I want to make 3d bas relief images on flat backgrounds. The completed backgrounds will be 1/4" white oak, cut from 3/4" stock. If itā€™s wiser to make the bas reliefs thinner than 1/2", I can taper or rabbet the panel backs to fit the required dadoes. They will serve as panels in a larger frame (each about 13" high, 9" wide). The first images will have fairly simple surfaces (smooth plaques, not feathers or twisty flames). If it goes well, the later images will be an animal (finer details).

  • Since the top surface will be completely removed, upcut bits make sense for the initial rough cuts. 1/4" 2- flute seems to be the most common; is it my best choice?
  • Oak is a hard wood. Is a tool coating useful? Do folks replace bits after some number of hours, or just when cuts no longer look good? (The wood isnā€™t cheap, I want to minimize losses).
  • Feed/speed charts seem to focus on what a tool can tolerate. But even if the bit can handle a speed, burning isnā€™t helpful. What feeds/speeds are best? (I have GWizard, but still new in using it, too).
  • For fine cuts, 1/4" ball nose seems popular, but even on the simple images my design shows tool marks near base of the 3d image. So is a tapered ball nose best here? What diameter?
  • The flat base will be ~1/4" thick (so Iā€™m removing 1/2" of oak). Milling that with 1/4" bit would be tedious, so I tried a design with a 2" spoilboard surfacing bit. That couldnā€™t reach some areas, and (with oak) itā€™s a little scary. Would most users apply a 1/2" mill? Other?

Finally, about designing: There are lots of videos about putting 3d images down in ā€˜scooped outā€™ circles. Can anyone recommend tutorials for what Iā€™m trying to do? (Iā€™m struggling to understand how VectricPro sets heights for 3d image and its base (not the underside).

6

I will take a shot at answering some of your questions based on my experiences.

Yes*

*are you using the makita or a spindle? If makita, yes. If a spindle, depends on your collet size. For ER11, sill most likely 1/4ā€ is your work horse. If ER20, 1/2ā€ 2 flute becomes your work horse.

In my experience, burning is most likely with too high a RPM (speed) and too low IPM(feed rate). Since I use Fusion 360, I set a chip load and F360 pick a feed rate based on the bit profile RPM.

Generally, setting feeds n speeds that the machine can handle as close to optimum for bit and material per manufacturer is what I go for. Again very generally, that means I drop chip load from ideal to something less as long as I can keep it above .001 (forget units inch per tooth??). Anything less than that and rubbing happens which will burn pretty quick.

I like 1/8ā€ tapered ball nose. Also, tool marks are a function of stepover. The smaller the step over the smaller the tool marks. You can get good surface finish with a 1/4ā€ ball nose with a 10% step over.

What we trade is sanding time for machine time. For instance, I did this with a .25mm tapered ball nose. I forget how long it took, but I seem to recall a hour at this size.

If the using a makita, please go watch the makita bursting into flames videos when using a 1ā€ surfacing bit and read post of issues here like Fire safety. . Second, surfacing bits do not plunge cut well even on a spindle that could handle a 2ā€ bit. If you manage to overcome all that, it is likely to burn oak even at optima feed rates.

Hope you find some use in my experiences.

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7

Thank you!

After posting, I saw a video that used a 3/4" bowl bit, which seems a lot safer.
I have a spindle with an ER 20 collet, but I hadnā€™t thought of using a 1/2" bit for roughing.

Today I worked on lettering in poplar. (Itā€™s a box used in dog training, so mistakes are very acceptable!) There are two surfaces for the lettering, so two Vectric files (and two .ngc files). It took an hour to figure out why the two surfaces differed. I tried varying depth of cuts, re-zeroed the bit, but nothing made them similar until I realized that for one of them I told Vectric it was a two-flute 60 degree V-bit, and the other I told it the bit was a single-flute 60 degree V-bit (which it actually was). The difference was unintentional, but the cuts were very different. Dunno why, but Iā€™ve now been warned that mistakes on the bit geometry make quite a difference.

The poplar experience also taught me that chip-out can be a problem. Some letters are so close that the fine space between them can (partly) split out. That will matter if I try to pour epoxy into them for contrast. It would also probably matter in the appearance of a carving in an open-grained wood (like oak).

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8

David - I use a 1.5" fly cutter routinely with my Makita. I donā€™t push it hard ā€“ I take light passes on the order of 1-2mm or <0.1" DOC. My router gets significantly hotter when I use a 3/4" bowl bit and clear large pockets. I think itā€™s a matter of how long you use the router and how hard you are pushing it (as Mitch mentioned). I will say the the Makita gets a lot hotter than I remember my Dewalt getting, but it might just be my imagination.

In any case, a VFD with a spindle addresses that issue, at a much greater expense.

-Tom

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