Working with the 10mm aluminum front plates from the DIY chassis. I'm trying to drill holes for a push power button, led, and attenuator.
I typically measure and start with a center punch, and then use stepped bits to open up a hole. Here's an example of a 1/2" hole I made in a panel today, to prove I'm not a complete doofus.
However, with the 10mm front panel, my bits are immediately becoming dull and sometimes breaking off. I was finally able to open the hole up to 1/8", but I can't get my stepped bit to catch in the hole. Right now I'm left with what feels like an ugly and expensive mistake, as well as a number of trashed bits.
I'm stuck and feeling a little discouraged. Surely there must be a way to drill through these front panels?
Should I be using a drill press and forstner bits? What am I missing here?
I typically measure and start with a center punch, and then use stepped bits to open up a hole. Here's an example of a 1/2" hole I made in a panel today, to prove I'm not a complete doofus.
However, with the 10mm front panel, my bits are immediately becoming dull and sometimes breaking off. I was finally able to open the hole up to 1/8", but I can't get my stepped bit to catch in the hole. Right now I'm left with what feels like an ugly and expensive mistake, as well as a number of trashed bits.
I'm stuck and feeling a little discouraged. Surely there must be a way to drill through these front panels?
Should I be using a drill press and forstner bits? What am I missing here?
With 10 mm thick alloy, a drill press is a must, along with a Drill Doctor bit sharpener. I use the slowest speed on my drill press along with thick cutting oil, I also sharpen each bit before I start. With most front panels, I use a drill press vise with rubber jaw inserts to hold the work and not damage the panel. C clamps to hold the vise to the drill press. You want the panel clamped for no movement while drilling.
Your photo of the two holes next to each other causes issues, you may want to send it out and have it CNC machined, drilling it is no longer an option, unless you use a hole saw with the larger hole as the center.
Your photo of the two holes next to each other causes issues, you may want to send it out and have it CNC machined, drilling it is no longer an option, unless you use a hole saw with the larger hole as the center.
This hole is intended to eventually broaden to 3/4" -- I was hoping to simply absorb the smaller hole in the final aperture. You're saying I can't do this?
If you use a 3/4" drill bit centered on the larger hole, when the bit starts to cut where the second hole is, the bit will chatter and either brake and/or cut an oblong hole. Either way, the bit will be dull on one part off the cutting surface. The drill bit will not like cutting into the second hole, lots of oil and feeding the bit with little force you MAY get away with it.
If you've never had to drill through something like this, get a thinner piece to practice with. The beginning of the cut on the second hole is the moment of truth. I usually "bounce" the bit into the second hole, gently , to get the cut started.
This is while using the procedure listed in my first post.
If you've never had to drill through something like this, get a thinner piece to practice with. The beginning of the cut on the second hole is the moment of truth. I usually "bounce" the bit into the second hole, gently , to get the cut started.
This is while using the procedure listed in my first post.
Use a hammer and punch to remove the broken bit, remember it was a stepped bit so drive it out the correct way. You can't drill the hardened broken bit.
As said, you need to remove it as that is what's causing your bits to dull. Try drilling a small hole from the other side and then punching it out.
Ok, this is all very helpful. Thanks everyone. My game plan will be:
-Knock out the caught bit with a hardened finish nail
If that all goes wrong then I can order a fresh front panel and I'll commit myself to back panel controls
Feeling frustrated tonight but I think I have a path forward. Fresh cup of coffee tomorrow morning should help
-Knock out the caught bit with a hardened finish nail
- pick up a drill press and figure out a secure clamping scheme
- pick up a bit sharpener
If that all goes wrong then I can order a fresh front panel and I'll commit myself to back panel controls
Feeling frustrated tonight but I think I have a path forward. Fresh cup of coffee tomorrow morning should help
Last edited:
You must also use lubricant when drilling aluminium, otherwise it gums up and sticks to your drill bit, as you've seen - the bit is not necessarily dull, it's just covered in galled aluminium. The usual lube choices are kerosene or wax, but really any light oil will make a huge difference. You should be able to get a bottle of cutting oil for a couple dollars at your local hardware joint.
Yes you need a sharp bit, but just buy a sharp bit. You don't need a sharpener unless you are doing production quantities.
Drill presses are excellent and I use mine for basically everything drilling-related, but the lube is more important than having a press. A press will not prevent the aluminium from galling, grabbing and breaking the bit.
When using a large twist-drill, you want a pilot hole that is slightly larger than the webbing at the centre of your large drill, but not much larger than that. If you grow the hole in many steps (e.g. 1/8, 3/8, 1/2), then the larger drill will want to wander. Do just 1/8 then 1/2".
Yes you need a sharp bit, but just buy a sharp bit. You don't need a sharpener unless you are doing production quantities.
Drill presses are excellent and I use mine for basically everything drilling-related, but the lube is more important than having a press. A press will not prevent the aluminium from galling, grabbing and breaking the bit.
When using a large twist-drill, you want a pilot hole that is slightly larger than the webbing at the centre of your large drill, but not much larger than that. If you grow the hole in many steps (e.g. 1/8, 3/8, 1/2), then the larger drill will want to wander. Do just 1/8 then 1/2".
Boelube was recommended to me--it works very well with 10mm Al and standard high speed steel bits
I think this is the first thread on this site where all of the contributors offer good advice and not the sometimes silly opinions.
Normally when you are drilling a hole with a bit diameter much smaller than the metal thickness this is considered deep drilling. When you deep drill you have to drill to a depth of about 1/2 of the drill diameter and then withdraw the bit to clear the chips.
With aluminum as mentioned a lubricant must be used to keep the aluminum from sticking to the drill bit. The classic lubricant was lard dissolved in kerosene. The best modern version is sold as “Tap Magic” for aluminum.
The other technique is to use a special center drill. It is a short tip on a stout body. It works well to drill pilot holes in thick material. Pretty much mandatory in using a lathe on long material. Works well for what you want for a pilot hole. Not to be confused with the very similar bit used to drill for properly countersinking flat head machine screws.
https://www.amazon.com/Anytime-Tool...ocphy=9005918&hvtargid=pla-524119198454&psc=1
Normally when you are drilling a hole with a bit diameter much smaller than the metal thickness this is considered deep drilling. When you deep drill you have to drill to a depth of about 1/2 of the drill diameter and then withdraw the bit to clear the chips.
With aluminum as mentioned a lubricant must be used to keep the aluminum from sticking to the drill bit. The classic lubricant was lard dissolved in kerosene. The best modern version is sold as “Tap Magic” for aluminum.
The other technique is to use a special center drill. It is a short tip on a stout body. It works well to drill pilot holes in thick material. Pretty much mandatory in using a lathe on long material. Works well for what you want for a pilot hole. Not to be confused with the very similar bit used to drill for properly countersinking flat head machine screws.
https://www.amazon.com/Anytime-Tool...ocphy=9005918&hvtargid=pla-524119198454&psc=1
So true. I can drill a 32mm hole 90mm deep in aluminium in about 5 seconds with a lubricant that is 95% water. If I stop the lubricant things go bad within a second or two...
A centre-drill is good for getting an accurate hole-location (no bit-wander when starting) but it is not a pilot hole. Centre-drills are, funnily enough, designed to give you a conical hole into which a lathe-centre can be inserted, to support long items with the tailstock.
A pilot hole needs to go all the way through, clearing out all the material that would otherwise be crushed and pushed aside by the web of the larger drill, instead of being cleanly cut by the leading chisel edges. Do a google image search for "web of twist drill" to get an idea of what I mean.
Obviously you very much need to use lube and preferably a drill press for making the pilot hole too 🙂 as it is more-risky in terms of drill-breakage than the larger hole, having a greater aspect-ratio.
Also: slower is nearly always better. You want a clean continuous chip being formed, which can require a fair bit of pressure - this is where a press really shines.
A pilot hole needs to go all the way through, clearing out all the material that would otherwise be crushed and pushed aside by the web of the larger drill, instead of being cleanly cut by the leading chisel edges. Do a google image search for "web of twist drill" to get an idea of what I mean.
Obviously you very much need to use lube and preferably a drill press for making the pilot hole too 🙂 as it is more-risky in terms of drill-breakage than the larger hole, having a greater aspect-ratio.
Also: slower is nearly always better. You want a clean continuous chip being formed, which can require a fair bit of pressure - this is where a press really shines.
Looks like I'll be the first to point out that making a case out of 10mm plate is not a good idea, even just the front panel. Which switches even accommodate 10mm wall thickness?
You can through drill with a center drill bit. That is what the smaller diameter bits do well. But you do need to clear the chips.
Fix everything in place and use some lubricant. Use HSS bits and you should be fine. Two blades bits are better for milling/drilling softer materials like aluminum and copper than four blades one.
Four blade bits are called milling cutters here!
1. What are you trying with a 10 mm front panel?
2. Use a drill press, and after every mm or so, go back slightly, it will not allow the bit to stick. Use any thin lube oil in an emergency.
HSS bits are suitable, carbide and carbon steel not needed.
And sharpen the bits to the correct angle for aluminum if you are OCD.
1. What are you trying with a 10 mm front panel?
2. Use a drill press, and after every mm or so, go back slightly, it will not allow the bit to stick. Use any thin lube oil in an emergency.
HSS bits are suitable, carbide and carbon steel not needed.
And sharpen the bits to the correct angle for aluminum if you are OCD.