Overzised surfacing bit and bitsetter problem?

CNC Machines Shapeoko 5 Pro
1

So I’m looking into an oversized surfacing bit for quicker surfacing. I’m talking about 3" / 75mm.

To be precise, this beast: SpeTool 2+2 Flute ATS Coated Insert 3" Dia 1/2" Shank Flattening Bits

Now I realized that the bitsetter diameter is too small and will ‘disappear’ into the indent of the bit. See below:

71hjlXmb4zL.SL1500
71hjlXmb4zL.SL15001500×1500 237 KB

I saw there’s an option in Carbide Motion to (temporarily) disable the bitsetter for the facing operation.

So is the way forward simply this?

  1. connect to Shapeoko
  2. go to settings and disable bitsetter
  3. initialize the machine
  4. move bit to zero position
  5. hit Zero All
  6. run the surfacing toolpath

(7. enable bitsetter again)
(8. continue with other Toolpaths)

I also read somewhere about putting a larger disk over the bitsetter and subtracting the height of that disk from your Zero, but I don’t see any advantage of the bitsetter for only a surfacing toolpath anyway?

2

I think the idea of a larger disk is to leave it on for all tools & set your zero normally.
The height is arbitrary, and is only used as a reference to determine the difference in tool lengths.

FWIW, my bitsetter has been in a drawer for a couple years. I just output paths by tool & set my zero manually.

3

That makes total sense, hadn’t realized this yet!
.

So for every different Toolpath you have to set the Zero again. But this wouldn’t work particularly well when doing a precise roughing pass and associated finishing pass(es) after…?

4

For every Tool. If I have multiple paths with one tool & output them together.
Works great with roughing & finishing. I can set my Z within 0.001" by eye.
And if it’s critical, I will also touch off to the previously cut rough surface & check the dimension.

5

It’s funny, I never realized I might put too much value in the bitsetter…

Besides that, I got a bit crazy from the machine to move to that thing OVER and OVER again. :laughing:

6

One solution that I have come up with is to do the new machine setup with the bitsetter off center to a ¼ bit. Once this has been done when I zero the surfacing bit it will now touch off on that edge that has the cutters on it.

⅛ and ¼ bits have not had a problem with being off center.

7

Nice trick indeed. The bit doesn’t have to touch the bitsetter exactly in the middle I suppose, if the knob is not pressed down in an ‘angled’ way. You didn’t had any problems with cutting heights/toolpaths being off?

8

Interesting. I’m trying to understand this a little better. Are you saying you consistently set each bit exactly the same each time? I use so many bits (sometimes 5 in a project and maybe 8-10 on a regular basis), that I can’t imagine NOT using a bitsetter.

Could you explain your process a little more?

9

You might be right for a quick surfacing job.

If you disable BitSetter, you must reset your Z zero every time you change the tool. When you reenable the BitSetter, you must reset the Z zero again.

Just follow that, and you’re good.

3 Likes
10

FYI, on my Pro (not 5 Pro) I found a couple of years ago that disabling/enabling the BitSetter required me to actually power cycle the machine, not just re-initialize. I can’t remember the weird behavior I got if sanding power cycle but it was repeatable. This was also on older versions of CM.

I don’t know if the issue still exists as that power cycle is just ingrained in my process now.

I believe @gdon_2003 experienced similar issues on his 3.

11

Would be good to know, as power cycling the machine would be as time consuming as the machine going to the bitsetter back and forth. Can anyone chime in on that?

12

This could be something you could use:

uxcell 2Pcs Stainless Steel Disc, 3 5/32"(80mm) Dia 0.07"(1.8mm) Thick 304 Stainless Steel Flat Round Sheet Blank Round Circle Plate

13

I’ve not seen a problem from it.

It started out as me loosening the bit setter and sliding it over just a bit when I needed the surfacer. Then later I was cutting a large sheet and needed the clearance. So I reset it.

14

I finally realized that I could simply position the bit to the zero point (or use the probe) and with a thin 1/47" fender washer resting on the Bit Zero button, let it use that. Quick and certainly close enough. When done with the surfacing bit, stow the washer and re-zero as usual for normal bits.

3 Likes
15

And I finally realized I wrote ‘overzised’ in the subject line instead of ‘oversized’… :laughing:

This is the thing with translating Dutch to English, same as Zwitserland (Dutch) vs. Switzerland (English). It doesn’t always end well in your head! LOL

1 Like
16

We are here to communicate, not pick nits, and I very much appreciate the international character of this forum.

17

I just gotta say, @NancynBob , that is a fraction I have never seen in my whole life… :slight_smile: And I am not picking nits, just expressing appreciation for a new experience. :slight_smile: :slight_smile:

1 Like
18

It was for our old LaSalle.

Think Edith and Archie singing “Gee our old LaSalle ran great!”

Actually ¼" will do. Much easier to find.

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19

:slight_smile: Back in the day (before I saw the written lyrics) I thought it was “gee, we’re all old, sour and gray”…

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20

I use the McFly, I leave the bitsetter enabled (SO 5 Pro), run the program, after the tool is measured, I remove the bitsetter from its location while the machine is flattening the wasteboard. Depending on how you set up your toolpath, you should have plenty of time to remove it. You can also remove it after the tool is measured and before you turn on the router and hit enter.

Since the wasteboard surfacing only uses one bit, it’s not a big deal.

After I am done facing the wasteboard, I reinstall it.