Im wanting to install insert holes in my waste board. Is it best to use the drill toolpath or the pocket tool path. My waste board is 3/4" MDF. I want to make 3/8" holes 4 inches apart. I was able to use Linear array to get the holes aligned just never used the Drill toolpath. Does it still do multiple passes as per the tool layout or does it just drill straight through the material?
The Drill path only makes sense if you have a bit the same diameter as the hole you want. Otherwise, Pocket.
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C3D added the drill path but drilling on a CNC is problematic. I would agree with Michael Hotchin that a pocket tool path would work better.
Just curious, why are you making dog holes in your spoilboard?
I have a Shapeoko 3 XXL and made my spoilboard with 1/4-20 Tee Nuts. I use cam clamps and L brackets to line up material. You did not say what type of machine you have but I have a document I created for the SO3 but is applicable for all machines.
spoilboard_considerations.pdf (1.3 MB)
Here is my how to for making L brackets in CC.
The problem with using threaded inserts on a wasteboard is eventually you have to replace the wasteboard. The time of installation and the expense of the inserts will be eventually lost. My approach is to use a 1/2” underlayment with an array of inserts with another 1/2” wasteboard with a matching array of holes. That way the holes can either be used for dowels for repeatable alignment, or the underlying inserts can be used. The wasteboard can be resurfaced many more times since there’s no inserts to crash into and it’s replaced quickly and easily.
My wasteboard solution
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As previously mentioned the drilling toolpath is only useful when the size of the hole matches the diameter of the tool. The advantage is you get options for pecking as you generally don’t want to drill all the way through most material in one pass. Drilling on a CNC is significantly limited because most of them aren’t designed for it and even plunge endmills aren’t really designed for drilling. You can use regular drill bits provided you have the collets to fit them, but slower rotation is needed for larger holes and you’ll often run into the limits of your machine. My machine has a limit of 8,000 rpm so the largest drill bit I can get away with drilling wood is about 3/16. For most holes your best bet is an undersized endmill and a pocketing toolpath.
I just did this a month ago on my machine. Wooden cam clamps with blind pocket holes.
Between double sided tape for the smaller parts that need holding the cam clamps all wood give me more piece of mind that WHEN the end mill goes sideways I won’t hit metal only something it will cut.
And it’s really fast to setup jobs and repeat things because everything can be indicated with a built in 90 degree wood stop on X and Y zero.
I recently replaced my spoilboard. I use the blue painters tape and super glue a lot for small projects with an L bracket to initially set the piece square to the spoilboard/router. After setting the project in place I remove the L bracket and replace it when the job finishes to keep the originally square set up of the L bracket. The sticky tape tends to get on my router bits and is a pain to remove. The blue painters tape some times gets on the bit but it is easy to remove. You might want to try the super glue and painters tape. I use Titebond Medium super glue and it has never failed me. With the super glue it has to set up but I just place the material before I get started and while getting the machine connected to the laptop and setting up the X Y and Z zeros the glue has time to set up. I could use the super glue accelerator but that is just more things I dont really need.
Since I replaced the spoilboard and on the last few projects I set the Bottom of stock in job setup to avoid cutting into the spoilboard so much. So far it as worked. However the first time I surfaced a piece I forgot and set the top of material in setup and when I moved the router over to the x and y position I also hit the zero + 6mm position and the bit came down on the work. So I reinitialized and used the BitZero to set the Z zero on top of the stock. Live and Learn. I have used the Z+6MM in the past where I always set the top of the project. Change is hard to remember sometimes.
When using the tape and superglue method what I will do is zero .025mm above the tape and then use the paper method to touch off on the top of the stock and rezero the Z making note of the difference which I use as the stock height in CAD. That way I cut perfectly through the material without gumming up the endmill with the tape. It takes a little longer, but works perfectly every time, especially with material that isn’t perfectly uniform in thickness.
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For tape residue, I use a bit of WD40 on a rag to clean. While cutting, I do not see an issue.
They really are not dog holes but 3/8" holes for threaded inserts. Im using short 5/16 threaded inserts in my waste board. These work great for both side clamps and hold down clamps. Also a great grid pattern for making sure things are square. Seems to work great for me. I can still resurface several times.
The problem with using threaded inserts for making things square is there will almost certainly be errors produced as the inserts themselves probably won’t be perfectly square and threads can’t do precision registration. It may be whatever error you get is well within what you’d consider acceptable for the work you are doing and that’s fine, but it’s something to be aware of in case you are having problems with getting something perfectly square and you don’t know why. This can also be verified with things like L brackets that can be checked with the spindle for square and will remain so as long as they remained secured to the wasteboard, but may not be so if they are removed and then replaced. I know lots of people simply leave their L brackets on all the time or machine pockets for them and this solution is perfectly fine for that. In my case I wanted something more flexible, so I use holes perfectly sized to fit 8mm metal dowels when I need the most precision or 8mm (~5/16") wooden dowels when I don’t.
Either way the intersection produced can be established as a macro to zero your X/Y. In the Run menu there’s a Quick Action button. On the resulting box there’s a User tab you can use to set up and repeat this operation. I have one set up for my most commonly used intersection in my wasteboard. You may or may not already know of this, but it’s quite handy for what you’re wanting to do.
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