# CNC routing thin wood question



## Electro Modder (Jul 30, 2012)

Hello, I have a quick question that I cannot seem to find any information about. (sorry if this is in the wrong forum btw)
Basically, I have purchased a mini (300x400mm) CNC router and am trying to cut thin, 3mm sheet wood (hardboard). I tried using this bit: Belin Single Flute Upward Spiral - Routing Cutters at 15000 - 20000rpm but it didn't work despite that they say it works with "woods". It just struggled and then stopped spinning even when not going all the way through. It HAS successfully cut thin, 2mm plasticard/styrene in the past with no problems whatsoever. So basically, does anybody know what the problem might be? I am thinking that it could either be the wood lifting up because it isn't clamped well, or maybe because the bit is an upward flute... If so, do I just need to buy a different type of bit for this purpose? Help would be much appreciated, thanks in advance.


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## RMCE (Jul 30, 2012)

*3mm sheet board problem*

I would try a left hand 2 flute cutter. This will push instead of pull the material toward the table


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## Phil P (Jul 25, 2010)

Hi EM and welcome to the forum

Several things come to mind; as RMCE says the material maybe lifting, so you'll need to look at how you are holding the work in place. For very thin materials you may need to look ate using double-sided tape onto a sacrificial MDF spoil board (which will need to be surfaced before use). The other things which come to mind are excessive feed speed and possibly lack of dust extraction. What spindle speed are you using, and what ir=s the feed rate? A 3mm cutter will feed a lot slower than a 20mm one, so maybe some experimentation is required. Again the use of a 1-flute spiral will restrict your feed speed over using a 2- or even a 3-flute cutter (you won't need a 3-flute design - they're designed to clear chips in 20 to 50 metre/min feed speed industrial kit). If you are not using an extractor please consider hooking-up your shop vac to the CNC - clean bits run cooler and the air flow from the vac also cools the bit

BTW guys, do you think you could at least edit your profiles to put in a First Name? It's much friendlier "chatting" with a "name" rather than N/a. Thanks

Regards

Phil


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## jw2170 (Jan 24, 2008)

Electro Modder said:


> Hello, I have a quick question that I cannot seem to find any information about. (sorry if this is in the wrong forum btw)
> Basically, I have purchased a mini (300x400mm) CNC router and am trying to cut thin, 3mm sheet wood (hardboard). I tried using this bit: Belin Single Flute Upward Spiral - Routing Cutters at 15000 - 20000rpm but it didn't work despite that they say it works with "woods". It just struggled and then stopped spinning even when not going all the way through. It HAS successfully cut thin, 2mm plasticard/styrene in the past with no problems whatsoever. So basically, does anybody know what the problem might be? I am thinking that it could either be the wood lifting up because it isn't clamped well, or maybe because the bit is an upward flute... If so, do I just need to buy a different type of bit for this purpose? Help would be much appreciated, thanks in advance.


Welcome to the forum.


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## Electro Modder (Jul 30, 2012)

Thanks guys, I have tried even using it with 18000rpm at as slow as 200mm/min feed rate. Is this still too slow? It was moving painfully slowly even at that speed! I tried sucking up the excess wood dust with my vacuum cleaner as it was going... but it literally cuts about a 10mm line before it fails anyway, there is hardly anything to suck up! Maybe I'm just not sucking it up quickly enough though... thanks again for the replies!
EM


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## Phil P (Jul 25, 2010)

Hi James

The spindle speed isn't too bad, faster would be better (say 24,000 rpm?). What happens if you try upping the traverse to about 1m or 1.5m/min, but with a depth of cut of 0.2mm? I'm beginning to wonder if the spindle is running in reverse or if the cutter is blunt.

Regards

Phil


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## Electro Modder (Jul 30, 2012)

Unfortunately the spindle can only go up to 20000rpm max, so I have to compromise with a low feed rate. The spindle is turning clockwise, and the cutter still seems to be sharp around the flute. It's barely been used!


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