# Looking for bit recommendations.



## DanT (Oct 22, 2012)

We run a cnc router mostly 2D cutting plastics. We don't have much experience with wood on the router. For the plastics we usually use a 1/4" spiral down cut bit. We have a project coming up that will require us to cut a lot of 5/8" plywood sign blanks. If someone could help me with selecting a bit that works best with plywood hopefully with one pass and at a production speed I would be grateful.


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## Quillman (Aug 16, 2010)

You could get through it in one pass if you have the power.
Would look at 5/8" shanked x 5/8 CD x 1" compression solid carbide spirals.
Would start with Onsrud.
Product speeds and running >1 shift/cutter? Then polycrystaline Diamond of which there are at least
a dozen sources world wide.


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## DanT (Oct 22, 2012)

Great thanks for the reply I will try that. I use Onsrud bits now. My router is 5hp but the largest collet I have is 1/2". I'll have to look at getting a larger one.


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## Cherryville Chuck (Sep 28, 2010)

If you go on ebay and do an advanced search for a seller named "Onsrudcutter2010" you will find some items that Onsrud has been selling at discounts. He has, a couple of times now, had 2 different 1/2" PCD bits for sale at about $45. I don't think they are recommended for general woodworking but at those prices it might be worth a try. I don't know if any are for sale right now but they may come up again. You may see some other bits there that might also be suitable. 

Fred (Onsrudcutter2010) is also a member of this forum but I haven't seen him post lately. I have bought numerous items off ebay from him and he is very knowledgeable about which bits are best for a particular job including feed speeds and cutting depths and he is very good about answering queries on same.


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## fixtureman (Jul 5, 2012)

You can use a .25 compression bit remember the larger the bit the more power you will need. I like Centurion bits good people there.


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## Quillman (Aug 16, 2010)

A single pass in 5/8 ply with a 1/4" bit?


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## DanT (Oct 22, 2012)

We have been using a .25 in two passes. It works ok but rather slow and we still break a bit on occasion.


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## GaryW (Dec 12, 2012)

*Change your cut depth per pass*

Change your cut depth per pass, .25 is a lot to force out. I use a .25 shaft mortsening bit, 1/4" cutting up spiral. The up spiral cut gets the dust up up and away, into the vacuum draft. I used to use .25, but have lower it to less then .200.
I have stopped breaking bits, especialuly on curves going across the grain.
Yes it may add one or two extral passes but it saves on the cost of bits. Are the few extra minutes of pass time worth the cost of bits. Two minutes aginst $40.


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