1. Wasting of valuable alcohol. Better to drink it.
Last time I used some motor oil.
2. I did. No problems so far.
3. I bought mine in closest hardware store for $2 or so. No any problem with them on aluminum.
4. If your hands are shacking because of p.1 it will not help.
5. I use taps with tips ground off. So far so good.
Making holes is not a rocket science BTW.
For the pros, this is what you want (I deliberately did not say what you need) :
Thread Solutions: Spiral Flute Cobalt Taps, Guhring 5592 Spiral Flute Machine Tap M3x0.5 Yellow ring Tap TiN
Expensive, but the spiral flute is ideal for swaf removal from deep blind holes. All you need in addition is a battery powered drill with a torque limiter, and very steady hands.
Patrick
Thread Solutions: Spiral Flute Cobalt Taps, Guhring 5592 Spiral Flute Machine Tap M3x0.5 Yellow ring Tap TiN
Expensive, but the spiral flute is ideal for swaf removal from deep blind holes. All you need in addition is a battery powered drill with a torque limiter, and very steady hands.
Patrick
1. Wasting of valuable alcohol. Better to drink it.
Last time I used some motor oil....
I use dish soap and water to lubricate cutting of aluminium.
"motor" oil has excellent low pressure lubricating properties.
Hypoid and vegetable oils are often designed to have good high pressure lubricating properties.
Cutting oils are designed to have ultra high pressure lubricating properties.
For cutting use a cutting oil.
I find that many cooking oils (olive, sunflower and rapeseed) makes an acceptable cutting oil for some grades of aluminium.
Hypoid and vegetable oils are often designed to have good high pressure lubricating properties.
Cutting oils are designed to have ultra high pressure lubricating properties.
For cutting use a cutting oil.
I find that many cooking oils (olive, sunflower and rapeseed) makes an acceptable cutting oil for some grades of aluminium.
I use dish soap and water to lubricate cutting of aluminium.
Which essentially is not too far from the industrial coolant
Fact remains though, that if you can spare a few cents for alcohol, you will get stronger and better looking threads, plus the tool life will increase.
In a tight spot, the dish soap water solution is sure better than any of the oil solutions though.
Magura
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You Sir, simply have to stop telling people about all the things you don't understand, and have no clue about in general.
Magura
Hello,
Lessons learned the hard way be and may not apply to you.
Drill ant tap the hole all the way through, no one will be looking down in between the fins.
Drill and tap a sample hole where it does not matter, just a test. I found some taps do not play with aluminum. No matter how careful you are the tap will break. Taps with two flutes cut less metal at a time and require less force to turn them. A tap broken off in the exact location where you need a thread is bad news.
DT
All Just for fun!
Try 4% milk for lube, not a joke.
Lessons learned the hard way be and may not apply to you.
Drill ant tap the hole all the way through, no one will be looking down in between the fins.
Drill and tap a sample hole where it does not matter, just a test. I found some taps do not play with aluminum. No matter how careful you are the tap will break. Taps with two flutes cut less metal at a time and require less force to turn them. A tap broken off in the exact location where you need a thread is bad news.
DT
All Just for fun!
Try 4% milk for lube, not a joke.
Just do not apply excessive force to the tap. If it doesn't go, remove it and clean. Aluminum and copper are tough metals and their swarf doesn't peel off like, for example, steel swarf. The same applies for drilling.
Which essentially is not too far from the industrial coolant
Fact remains though, that if you can spare a few cents for alcohol, you will get stronger and better looking threads, plus the tool life will increase.
In a tight spot, the dish soap water solution is sure better than any of the oil solutions though.
Magura
Hi Magura,
Which alcohol are you recommending, methyl, isopropyl, ethyl etc.?
David.
Plain ethanol is fine, but just about any type will work as far as I know, not that I have tested them all. Methanol I know for sure works as well, but is somewhat poisonous.
Magura
Naah, not quite so
Those materials has gotten a reputation for being tough to machine/drill/tap, but that is due to the methods and tools applied.
If the right tools and methods are used, both copper and aluminum are machining quite well, at least as well as steel.
Magura
EDIT: I just found a vid that actually shows how easy it is to machine copper, if done reasonably right.
http://www.youtube.com/watch?v=UX-avo5QZVc
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My experience has me agreeing with you 100%.
You Sir, simply have to stop telling people about all the things you don't understand, and have no clue about in general.
Magura
When I did my apprenticeship 28 years ago at a world famous English engineering company, they taught us to use paraffin for aluminium.
Works like a treat.
For tapping, there is no need to cool, since you are doing it at very low speed.
All you need to do is prevent sticking, or cold welding of aluminium to the cutting edge, which in turns becomes blunt and no longer cuts properly.
Patrick
Works like a treat.
For tapping, there is no need to cool, since you are doing it at very low speed.
All you need to do is prevent sticking, or cold welding of aluminium to the cutting edge, which in turns becomes blunt and no longer cuts properly.
Patrick
That is why I use thread cutting screws and, though it falls on deaf ears, recommend them.
Use the same lube (alcohol) on these as you would on the tap.
For the cost of 1 tap, you can buy 100 #4-40 x 1/4" tread cutting stainless steel screws. In my estimation, this is the best approach to small scale / limited experience building.
Jeez, you guys are crazy about aluminum tapping.
1. drill appropriate-sized pilot hole (mcmaster-carr or any other online reference works)
2. use tapping oil or acceptable substitute (WD-40 works fine)
3. back off a full turn every few turns down
4. done
If you are scared, just use a taper tap to start the tap (in a drill press is a good idea at the lowest speed) and then transition to a bottoming tap. So easy.
1. drill appropriate-sized pilot hole (mcmaster-carr or any other online reference works)
2. use tapping oil or acceptable substitute (WD-40 works fine)
3. back off a full turn every few turns down
4. done
If you are scared, just use a taper tap to start the tap (in a drill press is a good idea at the lowest speed) and then transition to a bottoming tap. So easy.
Not entirely, but how do you go about replacing mosfets then? My experience with self tappers, is that they sure don't work when put in the 2nd. time?
Magura
Self tapping screws do not allow the same level of pre-tensioning. Otherwise the entire world would be using them everywhere.
They are OK for tightening a cover of something, not for exerting pressure.
If you use a proper torque limiter with your battery powered drill, you will not break a tap.
And of course there are ways to remove the broken tap (depending on what facilities you have in access).
Patrick
They are OK for tightening a cover of something, not for exerting pressure.
If you use a proper torque limiter with your battery powered drill, you will not break a tap.
And of course there are ways to remove the broken tap (depending on what facilities you have in access).
Patrick
Not entirely, but how do you go about replacing mosfets then? My experience with self tappers, is that they sure don't work when put in the 2nd. time?
Magura
I have never had a problem taking them out and putting them back in (many times I've taken it out and put it in...
). It helps to treat them the same as 'real' screws and make sure you are threading them in straight and into the same, previously cut threads.
Using a hand screwdriver helps too, in first installing them and then re-installing them.
Give 'em a try
They can cut a tread of the same pitch and quality as a tap! How can this equal inferior results?
Thread cutting screws need to be harder and stronger than ordinary machine screws, to withstand the stress of tapping out the metal. This means they will most likely be more expensive, especially if you are using a large quantity. Machining and use of cheaper fasteners will be a cost saving for a large scale manufacturer.
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No doubt if you have CNC equipment or so and tools for them you can make holes and threads in one shot. But most DIYers have regular drill press (if any), regular bits and taps they can buy in nearest store. I used those regular tools to build three amps and two pre-amps - no problem. And I made all holes and threads (including blind holes with threads) without a super cutting oil, spiral taps or other fancy equipment. I'm not in a rush to make 100 holes/minute.
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