A section of my mold is made from an 1/8" sheet of mirror. I need to bolt another section to it. I need to drill a 3/8" hole through the mirror. The mirror is attached to a piece of 3/4" MDF for support. the mold is still in pieces, and the hole can be drilled before or after the two are attached. Can anyone recommend:
Drill bit or abrasive bit?
Type of lubricant?
Drill press or hand held?
Drill speed?
Thank you.
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They have a odd looking bit, its spade shaped, comes in several sizes. Ace has them.
Slow n steady with a diamond dust abrasive bit... make a ring with hot glue around where you want your hole to be and once cooled - fill that little reservoir you just created with mineral oil. Then slowly drill/grind through it with that diamond stone.
I've never done it myself - but read it from one of the books I have that has tips on lots of little things like that...
I used to make lots of bongs and went through lots of drill bits and bottles. once made a 7 chambered aqua bong out of AZ ice tea bottles all linked with tubes. the spade bit is opposite of the diamond stone, low RPM for the spade and when it starts breaking through go slower, or finnish with a diamond bit in a dremel. carbide tiped mason bits work also but again the point where the hole starts getting close to the bit size is when it is most likely to crack.
practice a few times and I used to use wax to cool the bit, if it starts to smell stab it in a block of parafin.
and yes I was the bong man in youth (carrots potatos house hold items car parts, gas masks and anything else.)
if a baked 14yo can drill a bowl and a carb in a orangina bottle, with a cordless black&decker 7v drill with a 2.99bit, I think you can figure it out.
just dont push hard, with the spade bit, and go slow, you will get a feel for the glass grinding. the diamond bit used to finnishe it off works just like a sander. cylinder bit after the spade starts to go through.
if you have a drill press use that,
lube wax worked for me but water should work fine
spade bit rpm not much more than 200 once you get started then as low as 30-60 when the hole starts to get big. I dont recomend going through with the spade bit, it tends to crack the glass at the last mm and does not come out perfectly round anyway. I think the mason bits work better but they may need a nick from the diamond to get started (as in a center punch for steel), still finnish that with a cylinder diamond bit for dremel.
or you can just buy a diamond glass drilling bit from a stained glass supplier. I think harbor freight had some a few months back
ok im babbling
good luck
Thank you for your advice. I'll be at the POLYCON trade show next week, but when I get back I'll try it. Thanks again. :=)
Just a bit of advice to add to the rest...if you can, set the mirror on a pad of stiff styrofoam and set up a way to keep a trickle of water running over the place you're drilling. This will speed it up, I promise, as well as keep the diamond-coating on the bit from wearing off as quickly.
What kind of bit would be the best for drilling through a thick glass bottle?
What kind of bit would be the best for drilling through a thick glass bottle?
Here is how I used to make all kinds of lamps from whiskey bottles. You need a bit of plasticine which you roll out into a strip 3 or 4 inches long. Make a cicle out of it and press it onto the bottle. You now have a well about a 1/4 of an inch high for the liquid you are going to use to to keep the glass cool where you are drilling. I used to use varsol, mineral oil or even kerosene. I would fill up the well, slow down the drill press as slow as it would go and use a carbide bit I would use the size that I could find grommets for to make sure the hole wouldn't abrade the lamp cord but not so big that the stones in the bottle could leak out.... Practice a couple of times on old bottles first. You can make a perfect hole after a while once you get to used to the speed at which to do it. It goes pretty fast and hold the bottle with a thick glove just in case. Make sure that hole is big enough for the cord and the plastic grommet. You can't drill a bigger one after the first as the glass usually shatters if you try it so make sure you have the right size first. Then just drill a hole in the cap the right size for the electical pipe to just slip in. Use a standard lamp pipe bolt to hold it tight on the bottom inside the cap. I used to use NEW fish tank gravel to fill the bottle from the top to hide the cord and give it weight so it would be balanced which I funneled in after I had the cord through the bottle.... Hope this helps.
JUST GO UNDER 60RPM AND YOU'LL BE FINE
AND ALSO, IF YOU ARE DRILLING INTO A BOTTLE, GET THE BIT TO GO INTO THE GALSS AT THE SAME ANGLE, ALWAYS GO PERPENDICULAR (90 DEGREES FOR ALL YOU DUM REDNECKS) TO THE GLASS, IT WILL CRACK USUALLY IF YOU TRY TO DO AN ODD ANGLE, GOOD LUCK