Drilling into copper?
 

Ok I am 100% copper machining n00b. I have a die simulator and a cartridge heater, and I want to make a hole in the die sim to fit the heater into. This seems straightforward enough in theory, but I dont want to **** up the simulator and I only get the one chance. Can I do this with a regular drill? What precautions should I take? I have WD40 and a fairly beefy hand drill at my disposal right this minute.

If you try and go in with the 1/4" (I assume if it is like the cartrige I got) it may tend to wobble and over bore the hole. Make sure the bit is a tough one as it will want to snap off if it is a cheap brittle one. I would really suggest a drill press and a good vice or at least a good bolted down vice to keep it from moving. Keeping the drill nice and strait maybe a challenge.

Igot given a load of small drillbits by a freind who worked at a electronics machine factory (they made very high tec objects de computation) The one 1.5mm bit he gave me I drilled 20+ holes 9mm deep into a 10mm peice of Cu with a drillpress, when it snapped I brought four others from a toolshop, they all snapped on the first hole!. The moral of the story is "Buy a quality drillbit" (though 1/4 should be strong 'whatever')...

I'd use a centre/drilpress and vice/hold~down as well, cause it's the sligthest side movement that will 'grab' and snap the bit. Keep it cool with WD40, so it does'nt make the Cu grabby. With a 1/4 drillbit you should be OK unless you do something careless. Use a sharp bit so you don't 'bow' the die (if it's quite a small peice or near to the edge) and apply the pressure gently, let the drill do the work, not your elbow :D ...

Is a pilot hole required? Or maybe he should use a centredrill(the ones with a pointed tip)?

With only one shot, a pilot drill is a good idea. On a drill press, of course.

Bob

Another thing to remember when drilling Cu is that you should take a little material and back out... let the temp drop a little and maybe hit it with a quick shot of WD-40 ...then do a little more.

A drill press is a must if it requires a very accurate hole. A mill with a collet system would be better.

If it's vital and going to cost big $ to replace... get it done at a machine shop. At least that way they have the right equipment.

Hope that helps... :dome:

What about using a punch, to make a centering hole for the drill press? It's #rotor's idea, I think.

We have a machine shop at work. I am going to ask around today and see if I can find out (a) who normally uses it and (b) if they will drill the hole in exchange for a six pack of beer :)

I've met some machinists that will center punch. Start with an 1/8in bit then slowly work there way up to whatever size they finally want. Keep the copper cool with WD40 and make sure the copper is exiting the hole. You should get some nice long strips of copper if its coming out right.

I drill a fair few holes in copper with a hand-drill. You should be fine, just need a steady hand, and make sure that you clamp the piece securely before you start drilling.

Mark the hole with a centre punch, otherwise with a hand drill, the drill will "walk" across the surface, and the hole will end up being in the wrong place.

Always drill a pilot hole.

Use low revs on the drill, I find that drilling at quite low speed makes the hole cleaner, and cuts faster, also, allows you to control the drill better, to keep it on line.

As with drilling any hole in anything, make sure that the piece is clamped in such a way that you're drilling straight down into it. Then get your eye right over the line of the drill and make sure that its going in straight.

Had an even better idea:

Gonna send it to #rotor and let him do the drilling for me. I am a wuss...

I was going to offer to do it....looks like you already got #rotor to get it done. While it is possable to get a fairly accutate hole with a hand drill, it is far from being the prefered method. Drill presses are 100% more stable and rigid that your hand could ever hope to be. Mills are even nicer...much easier to locate the hole exactally where it needs to be.

goody... :)

http://3rotor.homelinux.com/SCM-BB/c...l_dscn5778.jpg

Good God, thats a nice chunck of copper. Good luck preventing secondary heat loss. :D

I dono exactly how he is going to be using it, but with a couple of pieces of those furnace tile stuff, should be a breeze to insulate it properly.... I'm putting it into AutoCAD here, as we speak... :)

http://3rotor.homelinux.com/SCM-BB/c...tor/cad_01.jpg

excellent news.

I didn't make the die simulator myself; it's from Andrew LaMont at Millennium thermal. You'll find a lot of similarity between mine and this one:

http://www.overclockers.com/tips263/index02.asp

#rotor I am thinking you have it all figured out by looking at the link you sent. I am interested to see what you do with the CAD drawings though I must admit.

How stiff are those furnace tiles? Can one (for example) tap socket A or Socket 478 mounting holes into one?

I was more concerned about the surface area on the top. Going to be hard to insulate it with such a thin die. Lot of area there to release heat.

No question it isn't ideal. I have it here at the house tho and I am going to just go with it. I am tired of talking about testing and I am getting started asap. I'll just have to insulate it as well as I can and take it from there.

Well it should be consistant if nothing else. I like the tabs for clip on coolers.

the stuff is used to make ceramic kiln's with. Very similar to the Shuttle tiles, I can imagine... extremely soft, almost like polystyrene. Very easy too work with..... I have no clue where to get some of it though....

here is what I'm doing with it in AutoCAD
http://3rotor.homelinux.com/SCM-BB/c...tor/cad_02.jpg

just playing with different configs...

oh wow, thats quite the chunk as jaydee said. Although I do wonder what the purpos of such a chunk is?


#Rotor, I would suggest sticking them 1/2" below the die, so that the heat has a good chance to spread around a little. become more uniform to the little 'die'

where did those heaters come from? can you dimention them out in inches? Im kinda interested.


Jon

got sent to me with the block.
looks like 150W at 32v elements, from the writings on the side.
http://3rotor.homelinux.com/SCM-BB/c...l_dscn5790.jpg
they are 2" (51mm) long and

1/4" thick.... (6mm)

If the block is properly insulated, I highly doubt it to make much difference where the elements are going to be located. it's basically going to be one big-ass chunk of very hot copper, with only one little thermal pathway out.... Reason I Keep the elements close to the core seat, is to eliminate as much lag between induced heat and resultant temp difference in the measurements. All the heat coming in through the wires, will eventually have to go out through the seat, no other way...

When the rig is in balance, it would be easy to quantify the amount of heat being moved through the seat, and at what temperature this occurs. and that's all the variables required, If I'm not mistaken... :)

Hmm. I've been told (by people that I generally consider reliable sources) that a place I drive by everyday on the way to work makes the tiles for the Shuttle. I couldn't tell you the name of the place right now if my life depended on it though.

I suppose I could try some contacts and see if I could get some scraps...

from the cad drawing the holes for heaters look pretty near to the socket lugs. Might be a good idea to have them low enough to not interfere. That's in the rare case I would use the socket lugs anyway.

And by my calculations the cartidge heaters are good for ~ 40W at 12VDC (if both used) and ~95W at 18V if both used. 24V a single heater is over 80V. I am looking at this power supply:

http://cgi.ebay.com/ws/eBayISAPI.dll...category=32720

or similar. Something that'll go 12-18V would be ideal, but even at 12V (and under 4A total) the die sim should work ok.

the reason I say put them lower, is that there will be 2 really big hot spots right over them, and if the top isnt properly insulated those hotspost will transfer a good chunk of heat to the air around them.


Jon

They are Ogden Mighty Watt cartridge heaters #MWFX22-X (special order) left over from a project I did about 10 years ago. 0.25" dia. x 2.0" lg, 150 watt, 32 Volt, 7 ohm

Watlow also makes cartridge heaters - FireRod series. The problem with both of these sources is their stock heaters are designed to operate on 120 V or 240 V. I'm looking back into it - I'll post any findings in the Testing & Benchmarking > The Heat Die thread... :)

I think this is going to work much better,

http://3rotor.homelinux.com/SCM-BB/c...tor/cad_03.jpg

No matter where you place the heaters, temp stability is going to take the same time, as it is needed to heat all that copper mass. The only way to get a faster response time is milling away a big portion of that. Given that fact, it's preferable to have the heaters lower to get a more even heat distribution.

more or less like so...... :)

http://3rotor.homelinux.com/SCM-BB/c...tor/cad_04.jpg