I keep breaking my bits- What can I do

Hello everyone,
I’m a proud owner of a new X carve. I’m having some issues finding the right bit for a detailed carve on red oak. I’m starting pretty basic by creating wooden name plates for some of my co-workers. I At first I tried a 1/16 bit to carve my details but it was not carving enough details needed. I then used a 1/32 drill bits, but I broke two bits during my cuts. Is it that the wood is too hard for the bit or do I need a stronger bit. Any help would be grateful.

If bits are breaking you are operating them outside their performance envelope.
Can you share more information regarding your feed/rpm/depth per cut?
Also a little information regarding the designs themselves in case we can suggest a good work flow/bit selection.

I have snapped a lot of bits in my day. It happens.

What helps is to find the right RPM so that the bit is clearing material at the right rate, make shallow passes and don’t try to move the bit along too fast.

Drill bits make poor end mills. Their tips are deigned to make contact at one point (the tip) and they are not designed to be moved along that tip. There is also a long lever moment between the tip that contacts the workpiece and where the shank fits into the collet. This makes the bit break at the collet or where the shank necks down to the bit’s diameter.

The link below is meant as an example. I am not recommending this specific part. This configuration makes for a strong shank, keeps the working parts short so as to not form a long lever, has decent chip clearing and can cut as it is moved along.

https://m.alibaba.com/guide/shop/1mm-two-flutes-flat-square-spiral-bit-milling-tools-carbide-cnc-endmill-router-bits-hrc60-d1-3-d6-50_6036907.html

The best way not to break a 1/32 bit is simply not to use a 1/32 bit. I have found that a tapered bit with a .5mm tip works great for fine detail on most project and it is much harder to break a tapered tool. You can also use a 30 degree Vbit for fine detail without worrying about breaking it.

I left the recommended settings to feed rate of 30 in/min, plunge rate of 12 in/min and the depth of 0.015 in. per pass. The total depth of the project was 0.04956. The dimensions of the logo was 2in x 3in I was not able to capture the details of the design with a 1/16 bit. I thought the recommended settings was good enough for it to operate a good flow. What is recommended.

I get that but Easel dont generate the recommended feeds based on bit diameter - it is a fixed value. If you enter a large or small diameter the feeds dont change to reflect that.

So for your particular usage I would try the following starting point when using 1/32":
Feed 15IPM
Plunge 5IPM
RPM 16K
Depth per pass 0.025"

For the kind of small work you want to do I echo Allens recommendation of a tapered end mill or V-bit.
The problem for most 1/32" end mills are they are not single flute and that they are rather long. Therefore they break easily.

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Ok, I tried both methods. I tried Allen’s recommendation first, but it did not come out as smooth as what I expected. Then I went and tried the setting your recommended and again I broke a bit. I’m afraid to use another bit. I’m thinking on trying a 30 degree engraving bit. It seems strong enough to give me a fine finish. Any other recommendation? I forgot to mention that I made a similar name plate prior to this and use the 1/32 bit and it came out fine with no issues at all. Don’t know if this was beginners luck but the wood I used was the same, red oak.

The logo was made with the tapered ball tip, the letters was made with a 1/16 bit.

If you have wide areas to cut, the very small tips of the tapered or vbit will not give a good finish. You will need to do a two stage cut, where you use a .125 endmill to cut everywhere it will fit and then use the tapered tool to finish the areas where the .125 was to large. This will give you a nice smooth cut with fine details.

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Allen, Haldor,
You guys are great. I appreciate all your advice. I was a little hesitant about using the same bits again and went with the 30 degree engraving bit. I gave it a try and it worked really good. I did go ahead and lowered the settings with your recommendation. Hopefully I will get better as time goes by and move on to tougher projects. Thanks for all your help.

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Great to hear the settings are working for you :slight_smile:
You may want to keep a “book” of some sorts with the bit/feed details for your own future reference as each machine is different :slight_smile:

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Your sign looks great! Very crisp corners and smooth bottoms to the cuts. Getting that combination is one of the harder things to do.

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Good idea, thanks

Not knocking Haldor, because he’s one of the smartest dudes on the forum, but in my personal experience with 1/32" bits, 0.025" DOC is a tad much. As a rule of thumb, when doing standard pocket clearing, I don’t exceed the bit radius for DOC. For 1/32" that’s a mere 0.015625". I’ve been able to run at 30 IPM (in soft woods like pine, anyway - I’d dial it back a little for oak) at that depth with no problems.

…if you wanted to give the 1/32" bit another go. Looks like you came out with great results using the engraving bit!

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