Are hole drilling patterns available?

[dauntless]

I need to drill small holes through some core material on about 3/8" centers. The core comes in sheets up to 4' x 8' so I need a repeating pattern...anyone here know of a program to do that where I can define the spacing, boundaries and depth? TIA! Stan

[gc3]

http://www.vectric.com/

[zeykr]

If I'm not misunderstanding what you want to do, this should be pretty easy to do in aspire, vcarve pro or partworks with the vector copy command and the toolpath vector selector or template toolpath. Just a little time consuming on a 4x8 if holes are small.

If you want to supply size of material, size of hole, depth of hole, border inset etc, I'll see if I can make an example. I'm assuming a rectangular pattern?

[dauntless]

Thank you for the link, Gene, but I am not familiar with Vectric, so can't quite figure out your cryptic clue. I see they offer about 15 different software packages ranging from a few hundred dollars to a couple of thousand. Can you narrow the field any?

And thank you, Ken. I'm currently reading about the S_nest.sbp file, which looks like I can make work. Was just hoping to find an already-written short program. :)

[bleeth]

Stan: Since you own a Bot it came with a basic software package. Depending on age it is either Partwizard or partworks. You can draw your hole pattern there in a couple of miutes by placing one hole where you want it and then using the block copy tool to put it across the sheet.

[dauntless]

Ah...thanks Dave! I searched through the CDs that came with my 'bot, and sure enough there is a copy of Part Wizard v3.2b. I'll take a look at it.

In looking through the SbParts directory I also found sample_drill.sbp, which drills an array of using what appears on initial inspection to be the same three variables I mentioned at the outset. Thanks again, everyone!

[bleeth]

The design is easy. The tough part is the right tool, feed, and speed. When drilling a bunch of holes it will differ depending on your router/spindle, type of material, and how thick it is. You can build up a whole lot of heat when drilling holes fast with the wrong combination. Fires have started that way.
Post specifics for appropriate suggestions.

[srwtlc]

You could also use one of the 'Tools' apps called 'Drill Press'. In the control software, SB3, go to Tools/Drill Press or key in TD. You can do rows and columns or circular arrays.

[dauntless]

Thanks Dave. I use 1/8" and 1/4" 6 lb divinycell foam as core material in many of the products we make. To convert from wet layup to infusion, I need to be able to perforate the core to ensure proper air evacuation and resin flow, but my foam sheet supplier cannot perforate it to the specs recommended for this use, so I am looking to do it myself on the 'bot.

I was thinking to use an Onsrud 63-750 single edge upcut spiral o-flute. That tool has a 1/16" CED, 1/4" CEL and a 1/4" shank. I was planning to make the holes on 3/8" centers with a 1 ips plunge and move at maybe 2 isp. It would take a while to perf an entire sheet, but when I was done I can cut it and use as needed without having go through the perf drill every time. Thanks...Stan

[dauntless]

You could also use one of the 'Tools' apps called 'Drill Press'. In the control software, SB3, go to Tools/Drill Press or key in TD. You can do rows and columns or circular arrays.
BINGO!!! :D

Way to go, Steve...that's exactly what I was hoping to find. Thank you! :)

[bleeth]

punching divinycell those thicknesses is pretty easy but not sure an upcut is the answer as even that small a diameter might tend to lift the sheet a bit. Also with a 1/4" CEL and 1/4" sheet you can have a bit of an issue. If you are running a spindle you might want to use a drill bit and slow the spindle speed down.
Drill bit City can fix you up with longer CEL drill bits and they also have a collet adapter to go from a 1/4" collett to 1/8" for the bits.

http://drillcity.stores.yahoo.net/10fracpac.html

The drill press tool is lower limit on hole size at .125 but you can lay it out for the centers and just use your .0625 bit

[dauntless]

Thanks, Dave! I ended up getting a downcut o-flute with a CEL of 3/8" from another supplier to address the issues you raise. And I have an 8th inch adapter for the quarter-inch collet on my router, so will take a look at the Drill City items. I hope they can withstand 10k rpm, as that's as slow as my machine goes. Cheers! Stan

[dauntless]

I finally got around to using the "Drill Press" subroutine yesterday, and man was I pleased with the output. I needed to drill 3/32" holes on .5" centers in an 18" x 24" piece of .25" divinycell foam core, so just stepped through the worksheet and let 'er rip! Here's a detail photo. The larger holes you can see are .125" diameter on 4" centers in staggered rows...not good enough!

[bleeth]

Glad you're getting a system going that works for you Stan. Now Hit It!!

[Greybarn]

We do a lot of infusion in 3/4 and1 inch core. Our typical center to center distance is about 4inches. But the pattern is also dependent on the resin viscosity. Our normal infusion resin is about 150 cps. If you are anywhere close to that then you don't need anything tighter. Also the hole diameter does not need to be anything larger than 3/16".
Regards
Peter

[dauntless]

Thanks for the replies, guys. Peter, I use an infusion epoxy with a cps of 295 or 380, depending on which hardener I use. Don't know if that qualifies as close enough or not. I used .5 spacing on the advice of a friend in the aviation composites business. He also recommends very small holes...I use 3/32, but he is encouraging me to go down to 1/16 or less, as the holes are really only there to ensure an escape path for air. In any case, doing this with the shopbot and infusing the pieces sure beats drilling the holes by hand and wet layups... :D

[Greybarn]

With the viscosity in that range, then I would agree with the spacing that yruo firend has suggested is about right. We have recently been using a DOW resin that has a viscosity in the 350cps. That viscosity range needs a lot of infusion lines and passages to move the resin into the part.
Alternatively, you could increase the spacing, and use a vee bit to scratch a shallow (less than a 1/6" deep) groove into the surface with the intersections at each of the holes. If you offset the hole pattern, then you can get away with fewer holes. The trade-off is that you have to change bits.
I agree about the diameter of the hole. The only issue is that we have broken the bits when we have gone smaller than 1/8" diameter (but we are also drilling deeper too).
Regards
Peter

[dauntless]

With the viscosity in that range, then I would agree with the spacing that yruo firend has suggested is about right. We have recently been using a DOW resin that has a viscosity in the 350cps. That viscosity range needs a lot of infusion lines and passages to move the resin into the part.
Alternatively, you could increase the spacing, and use a vee bit to scratch a shallow (less than a 1/6" deep) groove into the surface with the intersections at each of the holes. If you offset the hole pattern, then you can get away with fewer holes. The trade-off is that you have to change bits.
I agree about the diameter of the hole. The only issue is that we have broken the bits when we have gone smaller than 1/2" diameter (but we are also drilling deeper too).
Regards
Peter

Those are really good suggestions, Peter, and I will do some experimenting with increased hole spacing. As it is I can do an entire 4x8 sheet in a little over an hour, and since I'm not building anything like the size of a boat, that works well for me. Thanks again!