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200,000 holes!

TwoWheeler

Aluminum
Joined
Jan 25, 2021
For an upcoming project, I need to make 200,000 2.5mm thru holes in an approximately 5' square piece of G10, .2in thick. (That's POINT 2 thick - ninja edit)

The weapon of choice is a Thermwood router and the software would be FeatureCAM.

Not being all that familiar with the material, and for the sake of starting somewhere, I told FeatureCAM the material was "plastic" and that I wanted 3000 RPM and it gave me 4.22IPM as a feed. I called a 3/32 drill bit and the software said .0938 peck in a chip break cycle.

Should I peck more? Less? Do those speeds/feeds sound like a reasonable starting point? (I will be given some material to experiment on).

Also, I'm thinking with that many holes, drill wear/breakage will be a factor. My first thought was to program the holes in sections/quadrants (and since the entire piece of material will be Swiss cheese-ed, it looks like it's going to involve moving whatever clamping contraption I can concoct). That would allow me to restart a section, rather than start from Hole one, all over again....especially when the drill breaks on hole number 199,999!

Given that I'm going to need to move clamps around, I'm pretty sold on the quadrant idea, but can I refine it further? I'm not sure if the Thermwood will allow you to search/start from a line number - if it does, could maybe I coordinate line numbers with holes, so that I can start somewhere in the vicinity of where the drill went south....or the power went out....or whatever.


Thoughts?
 
For an upcoming project, I need to make 200,000 2.5mm thru holes in an approximately 5' square piece of G10, 2in thick.

The weapon of choice is a Thermwood router and the software would be FeatureCAM.

Not being all that familiar with the material, and for the sake of starting somewhere, I told FeatureCAM the material was "plastic" and that I wanted 3000 RPM and it gave me 4.22IPM as a feed. I called a 3/32 drill bit and the software said .0938 peck in a chip break cycle.

Should I peck more? Less? Do those speeds/feeds sound like a reasonable starting point? (I will be given some material to experiment on).

Also, I'm thinking with that many holes, drill wear/breakage will be a factor. My first thought was to program the holes in sections/quadrants (and since the entire piece of material will be Swiss cheese-ed, it looks like it's going to involve moving whatever clamping contraption I can concoct). That would allow me to restart a section, rather than start from Hole one, all over again....especially when the drill breaks on hole number 199,999!

Given that I'm going to need to move clamps around, I'm pretty sold on the quadrant idea, but can I refine it further? I'm not sure if the Thermwood will allow you to search/start from a line number - if it does, could maybe I coordinate line numbers with holes, so that I can start somewhere in the vicinity of where the drill went south....or the power went out....or whatever.


Thoughts?

Does your router have a toolchanger?

Featurecam can do basic tool life management - switch to a different tool after x number of minutes.
 
Both your programming ideas are solid. G10/FR4 is a fiberglass laminate. It is going to be brutal on your drills. Even carbide.
I did a job out of it once, but that was years ago so I don't remember much.
 
200,000 holes, pecking 2" deep? In G-10? (It's got glass in it)

Rough guess is 3-1/2 months running 24/7, based on a minute a hole. Chip break wouldn't be sufficient, I don't think. You're gonna need a full retract to clear the chips.

I'd think a diamond gundrill, and compressed air thru the tool to clear chips, would be the only practical solution. Which probably requires a different spindle.
 
At 200k holes I would be contacting some drill manufacturers. OSG used to make some really good plastic tools for CFRP, but I'm sure you can find more options as well.

For that awful G10, you might want a dreamer or something unusual. This is going to take a lot of time, and burn up a lot of tooling. Having the right tool is going to pay off pretty quick. You need something specific for your application.

A good sales rep can find the right tool and give you all of the parameters you need to make it work.
 
Talk to manufacturers of circuit board drills- PCBA fabs are made from G10 or G10 like material. Fabs are still cut out with routers and there is still a fair amount of through hole board technology out there.
 
Sadly, no.

Well, I assume it has the ability to use more than one tool offset? (I know nothing about your machine, sorry)

As long as it can do multiple tool offsets and your post can handle manual toolchanges, the tool life feature in featurecam should still help you avoid splitting the hole pattern up.
 
Well, I assume it has the ability to use more than one tool offset? (I know nothing about your machine, sorry)

I don't know all that much about it, myself! The current operator is retiring, so I'll be taking it over.

I assume it does have the ability to use multiple work offsets, so that might be a very good way to break the pattern into manageable chunks and/or find a place to restart, should I need to.
 
Look, the water jet will leave relatively round holes, rather straight (cylindric). If you need them within tighter tolerance, a second operation might become necessary. I’m thinking of grinding laps you can do with the router, something fast on it like a Dremel with a corundum stone.
 
Hmmm! 2.5 mm holes 50 mm deep spaced with a web of about .9 mm. G10 (circuit boards) are normally drilled with short carbide drills. thin stuff ... 1.5 to 3 mm board.
50 mm is 20X dia so easily qualifies for a gun drill. G10 is pretty abrasive since it is glass fiber filled. My off the cuff thought is to countersink since gun drills like to get started straight ... or provide a drill bushing to get it started straight. Use air to cool and evacuate the dust. Trap the dust with a vacuum of some kind. Diamond coating may extend the life of the drill.
To put it mildly; a very interesting project.
 
I wondered about the 2" ... but.
Oh well! Orders of magnitude only count in paychecks ... right?
Modify my last post ... carbide drills and air to cool. Good luck!
 
Definitely contact multiple tool reps, and do sample parts to prove out their tools and parameters before chewing into the real part. You don't want to have to deburr that backside too much.
 
Easy peasy, get a diamond coated drill. a GOOD one.
In fact you're probably going to need 3-4 of them if I had to venture a guess depending on your speeds/feeds.
 








 
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