+1 on pig fat being the best lubricant for aluminum.
Also for punching and shearing, it makes cutting edges perform much better.
I have aluminum sheet custom rolled for me in special no-waste sizes (they are multiples of chassis sizes) and laminators use it; aluminum sheets slightly smell of it but I wash them in a lye solution anyway to slightly pickle surface for better paint adhesion so no big deal.
For those concerned: they use rendered fat which of course does not rot, it only slowly oxidizes in contact with oxygen.
That said, much respect for Country to Country Cultural/Religious differences 🙂
Also being a History lover, much aware of the Sepoy Mutiny of 1857
Also for punching and shearing, it makes cutting edges perform much better.
I have aluminum sheet custom rolled for me in special no-waste sizes (they are multiples of chassis sizes) and laminators use it; aluminum sheets slightly smell of it but I wash them in a lye solution anyway to slightly pickle surface for better paint adhesion so no big deal.
For those concerned: they use rendered fat which of course does not rot, it only slowly oxidizes in contact with oxygen.
That said, much respect for Country to Country Cultural/Religious differences 🙂
Also being a History lover, much aware of the Sepoy Mutiny of 1857
I've read that nothing beat whale oil as a cutting lubricant, and apparently the smell ensued that you had the bus to yourself on the way home. I just use anything oily to hand, usually sewing machine oil or ROCOL tapping lub. Soap is supposed to be good on stainless steel.
Unfortunately there was a run on whale oil in the American Midwest at the beginning of the pandemic
Blaser, Carborundum Universal (part of St. Gobain), and Grindwell Norton, among others, make a vast variety of cutting and EDM oils.
Also, our temperature, which hovers around 40 degrees here for 9 out of 12 months, has to be borne in mind.
And really, for occasional use or jobs, not needed...or find a competent machine shop.
Also, our temperature, which hovers around 40 degrees here for 9 out of 12 months, has to be borne in mind.
And really, for occasional use or jobs, not needed...or find a competent machine shop.
Sure did! https://www.diyaudio.com/community/...lu-and-broke-my-bits-help.380745/post-6885167
Thanks for checking back in
Once you have extracted the broken bit, I‘d recommend to either
- get the hole done with a cnc-miiling-machine (expensive, but precise)
- really really make sure you have the panel and the drill (3/4“ you said) very tight.
i had this too, but neither a drillpress or a cnc. Adjusted the hole with a lime and continued. It was a major PITA, and the hole isn’t round but roundoid…
edit:I see you got it! Great!
Thanks folks! For me this hobby is just as much about learning how to do things the right way as it is listening to the finished gear.
Drill press is not required, but useful and safer. Both for you and the work.
Quality of the bit matters. Speed, cutting fluid, pressure. If you visit the machinist sites, you will find out a lot more about drilling than is obvious.
A step bit is designed to use in a starter hole.
FWIW, I never succeeded in doing anything but destroy small bits on a Drill DR. and larger bits I can do better by hand. Buy those 1/8 bits in the short length in 10 packs from machinist supply houses. Use those junk bits from the big box store for drilling sheetrock and studs. Just because it says HHS or is some fancy color does not mean it is any good.
Quality of the bit matters. Speed, cutting fluid, pressure. If you visit the machinist sites, you will find out a lot more about drilling than is obvious.
A step bit is designed to use in a starter hole.
FWIW, I never succeeded in doing anything but destroy small bits on a Drill DR. and larger bits I can do better by hand. Buy those 1/8 bits in the short length in 10 packs from machinist supply houses. Use those junk bits from the big box store for drilling sheetrock and studs. Just because it says HHS or is some fancy color does not mean it is any good.
Oh, one more thing, stainless steel can also be sticky to machine, so if you need to, just bear the above tips in mind: secure clamping, drill press, relieve the pressure, fluid, and go at a reasonable feed rate.
Here's a set of $25 center drills (#1 to #5) at the best tool vendor in USA, MSC Direct:
https://www.mscdirect.com/webapp/wcs/stores/servlet/product/details/77426872
https://www.mscdirect.com/webapp/wcs/stores/servlet/product/details/77426872
Heres a photo of the finished product
Now that I've figured out how to get through the front panels, I'll be adding a matching switch and LED to the power amp. Maybe an attenuator in the DAC too so I can run my whole rig with two boxes.
Now that I've figured out how to get through the front panels, I'll be adding a matching switch and LED to the power amp. Maybe an attenuator in the DAC too so I can run my whole rig with two boxes.
there are many types of aluminium, some are better machineable than others. there are special drill bits for aluminium, they have a larger top angle than the steel ones approx 116 degrees instead of the usual 90. the typical cutting speed for aluminium is up to 60m/sec. the less machineable material behaves like butter, and it leaves a chip behind the bit attaching to the material. in had the best success with cobalt type drill bits. always use cutting fluid.
Just sharing what I have learned, heat is enemy of any cutting tools.
I have used HSS drill bits to drill Aluminium(14mm) and Steel Plate(around 7mm) with drill bit still sharp.
1. Peck drill and keep spraying water into the hole, I have a small spray bottle.
2. Keep clearing the chips and keep checking the tip of drill bit to make sure Aluminium has not welded to bit due to heat.
3. Drill bit should be straight. Use a guide or drill press.
I have used HSS drill bits to drill Aluminium(14mm) and Steel Plate(around 7mm) with drill bit still sharp.
1. Peck drill and keep spraying water into the hole, I have a small spray bottle.
2. Keep clearing the chips and keep checking the tip of drill bit to make sure Aluminium has not welded to bit due to heat.
3. Drill bit should be straight. Use a guide or drill press.
TiCN coating on a quality bit, lubricated/cooled works very well in aluminum, even the unusual 1000 series “pure” aluminum alloys, which are really gummy, like OFC, to drill. (But OFC should use a flood of motor oil- really messy)
Straight acetone is a good coolant for aluminum, but a popular “cocktail” of the old timers is ATF and acetone blend.
I have a bottle of stinky “dark thread cutting oil” sold for black iron pipe threading that is the easy go-to. Available at the box store.
And peck drilling is the way to go. Get cheap acid brushes so you can clear all the chips and apply oil at once after each peck. If you feel the work getting got, take a break and resume after it has cooled.
Straight acetone is a good coolant for aluminum, but a popular “cocktail” of the old timers is ATF and acetone blend.
I have a bottle of stinky “dark thread cutting oil” sold for black iron pipe threading that is the easy go-to. Available at the box store.
And peck drilling is the way to go. Get cheap acid brushes so you can clear all the chips and apply oil at once after each peck. If you feel the work getting got, take a break and resume after it has cooled.
