My aleph-X heatsink now contains a M4 broken tap 
I read somewhere that there is a posibility to remove this by bathing the heatsink into an "alum" solution. What kind of acid is this and what is its formal name so I can search for it in the local market? Is it sulfuric acid maybe or something else? Anybody ever tried a similar solution to such a problem?
I read somewhere that there is a posibility to remove this by bathing the heatsink into an "alum" solution. What kind of acid is this and what is its formal name so I can search for it in the local market? Is it sulfuric acid maybe or something else? Anybody ever tried a similar solution to such a problem?
Can't you just leave it in and drill another hole? Sometimes all the effort that don't guarantee success is simply a waste of time. I broke #4 tap recently and spend and hour trying to remove it in vain.
M4 is not that small so you could try to drill it through and use easy out to take it out, but I don't think it's even possible.
How about using liquid nitrogen?
M4 is not that small so you could try to drill it through and use easy out to take it out, but I don't think it's even possible.
How about using liquid nitrogen?
panos29 said:My aleph-X heatsink now contains a M4 broken tap
I read somewhere that there is a posibility to remove this by bathing the heatsink into an "alum" solution. What kind of acid is this and what is its formal name so I can search for it in the local market? Is it sulfuric acid maybe or something else? Anybody ever tried a similar solution to such a problem?
It happens even to Peter it seems. Last time (implying that it happened more than once...) I drilled a small hole from the outside of the sink, went and got my most reliable sinker punch and my biggest hammer and beat the pore little tap through the hole with threads and everything. Worked perfectly for me and I filled the hole with a black bolt from the outside and nobody will ever know what I did.
Try at you own risk.
Prevention is better than cure
After twisting off several taps, I now make a a habit to liberally douse with oil and pull out the tap to clean the shavings.
One of my big fears was tapping to hold a circuit board and the transistors and breaking off on one of last holes. But since improving my technique it has been trouble free.
But the #4 taps are very easy to break.
George
After twisting off several taps, I now make a a habit to liberally douse with oil and pull out the tap to clean the shavings.
One of my big fears was tapping to hold a circuit board and the transistors and breaking off on one of last holes. But since improving my technique it has been trouble free.
But the #4 taps are very easy to break.
George
I asked this question and got some great responses as well as some great sympathy
There are some helpful ideas in this thread
mlloyd1
There are some helpful ideas in this thread
mlloyd1
panos29 said:My aleph-X heatsink now contains a M4 broken tap
Have not tried this in Al, but I once broke off a 2-56 tap in OFC (copper) and got it out with nitrol etch solution (dilute HNO3 and ethanol). The solution removed just enough of the surface to reduce the friction such that I could ge a tap extractor down the flutes of the tap and back the tap out.
Some of the machining fluids intended for steel are slightly corrosive to Al and are alleged to be usefull in the same manner after an overnight soak.
Don't have this sort of thing happen very often.... usually I just remake the part. If it's complicated or expenisve, often the damaged portion can be cut out and repaired with TIG or plasma torch.
If you don't have access to such things..... make friends with someone who does!
Cyclotronguy
Some of the machining fluids intended for steel are slightly corrosive to Al and are alleged to be usefull in the same manner after an overnight soak.
Don't have this sort of thing happen very often.... usually I just remake the part. If it's complicated or expenisve, often the damaged portion can be cut out and repaired with TIG or plasma torch.
If you don't have access to such things..... make friends with someone who does!
Cyclotronguy
Unfortunately tis is a blind hole ending right on a fin
I tried to drill through the broken tap with my dremel and a cobalt drill but he tap seems even harder than cobalt! Its a new type of tap bought last week that seems twisted like drills, a really super one with very quick taping but obviously it is a bit harder than it should . I tapped around 40 threads on that sink and the %$#@% last one did the wild thing to me! I really hate it, but i am sure you know that feeling very well! I will try some sulfuric acid on the rest of the tap this weekend and I will let you know. I guess after 40 or so threads I had to take some rest
before the next one....next time better luck.
Hey till! nice horny horns you got there in your ....U-lab! wish I could make a pair as well as you did!
I tried to drill through the broken tap with my dremel and a cobalt drill but he tap seems even harder than cobalt! Its a new type of tap bought last week that seems twisted like drills, a really super one with very quick taping but obviously it is a bit harder than it should . I tapped around 40 threads on that sink and the %$#@% last one did the wild thing to me! I really hate it, but i am sure you know that feeling very well! I will try some sulfuric acid on the rest of the tap this weekend and I will let you know. I guess after 40 or so threads I had to take some rest
before the next one....next time better luck. Hey till! nice horny horns you got there in your ....U-lab! wish I could make a pair as well as you did!
It happened to me once....
I knew at once that I could do nothing about it; the tap is a 1000 times harder than the aluminium heatsink, so if you try to go in, you will always end next to it in the alu.
Then I decided to take it with me to a friend of mine, who is a dentist!
He had the means (diamond thinnies...) to cut it out for me...
So my advice is: make sure you´ll have a dentist in your circle of friends (and also: don´t go there for tooth-ache but only for hifi).
Regards,
Lucas
I knew at once that I could do nothing about it; the tap is a 1000 times harder than the aluminium heatsink, so if you try to go in, you will always end next to it in the alu.
Then I decided to take it with me to a friend of mine, who is a dentist!
He had the means (diamond thinnies...) to cut it out for me...
So my advice is: make sure you´ll have a dentist in your circle of friends (and also: don´t go there for tooth-ache but only for hifi).
Regards,
Lucas
Panos:
If it's a blind hole, just grind it off and forget about it. When you close up the amp, neither you nor anybody else will see it. It's not so bad!
Just make sure that you use oil when you tap the replacement hole. ... and back it up after the clutch slips each time. Like Peter says, if you set the clutch on the drill correctly, it's almost impossible to break the tap.
If it's a blind hole, just grind it off and forget about it. When you close up the amp, neither you nor anybody else will see it. It's not so bad!
Just make sure that you use oil when you tap the replacement hole. ... and back it up after the clutch slips each time. Like Peter says, if you set the clutch on the drill correctly, it's almost impossible to break the tap.
My first move used to be hiding the evidence before my dad found out that I'd ruined another one of his taps. Its not that he wasn’t patient, I just managed, in spite of good instruction, to bust more than my share of bits and taps.
If you’ve got enough of the tap to grab onto with some tiny vise-grips, you might try heating the aluminum from the opposite side with a heat gun. Aluminum will expand at about twice the rate as steel, if not making the hole bigger, perhaps looser.
DO NOT try this with a butane torch gas burner or other flame source, might screw up the aluminum. I doubt that a hair dryer would get hot enough. Ten minutes in the oven at 450 degrees might work OK without goofing things (works for chocolate chip cookies). I haven’t tried this myself, but Peter's comment about the liquid nitrogen reminded me of some old physics experiments that would suggest that just such a thing would be possible.
If you’ve got enough of the tap to grab onto with some tiny vise-grips, you might try heating the aluminum from the opposite side with a heat gun. Aluminum will expand at about twice the rate as steel, if not making the hole bigger, perhaps looser.
DO NOT try this with a butane torch gas burner or other flame source, might screw up the aluminum. I doubt that a hair dryer would get hot enough. Ten minutes in the oven at 450 degrees might work OK without goofing things (works for chocolate chip cookies). I haven’t tried this myself, but Peter's comment about the liquid nitrogen reminded me of some old physics experiments that would suggest that just such a thing would be possible.
Re: Re: Re: Prevention is better than cure
"Especially when you do 250 holes and try to work fast
I used cordless drill gun with clutch and it took me only 2 hours or so."
Next time you get on a plane ask yourself how many broken taps does it contain,
and wheter the higher weight on one wing (in broken taps) may unbalance the plane.
I stopped using #4 taps, which is about the same as M3, in anything thicker than 1/8, and I no longer use battery powered drills to tap.
No matter how hard is the punch you use, the tap is always harder. I broke two punches ones trying to hammer out a tap from behind.
The only thing harder than that is an abrasive tip an mounted on a dremmel. once I broke a 3/8 tap into a 1/2 Al plate and I was able to dremmel that sucker out of there redrill and retap (very slowly) to 5/16. It took an hour and three dremmel abrasive tips.
"Especially when you do 250 holes and try to work fast
I used cordless drill gun with clutch and it took me only 2 hours or so."
Next time you get on a plane ask yourself how many broken taps does it contain,
and wheter the higher weight on one wing (in broken taps) may unbalance the plane.
I stopped using #4 taps, which is about the same as M3, in anything thicker than 1/8, and I no longer use battery powered drills to tap.
No matter how hard is the punch you use, the tap is always harder. I broke two punches ones trying to hammer out a tap from behind.
The only thing harder than that is an abrasive tip an mounted on a dremmel. once I broke a 3/8 tap into a 1/2 Al plate and I was able to dremmel that sucker out of there redrill and retap (very slowly) to 5/16. It took an hour and three dremmel abrasive tips.
Alum solution
Found this site that describes the ALUM process you referred too. If you go this way, you should try it some scrap sock to see what to expect in terms of etching or coloring the heat sink. You might have to bath tem both to get them to match.
http://www.metal-club.org/Remove.html
Heli-coils are great!
I hope if the airplanes I'm on in the future have ever needed airframe repairs that someone as detail oriented as Peter made the repairs.
Found this site that describes the ALUM process you referred too. If you go this way, you should try it some scrap sock to see what to expect in terms of etching or coloring the heat sink. You might have to bath tem both to get them to match.
http://www.metal-club.org/Remove.html
Heli-coils are great!
I hope if the airplanes I'm on in the future have ever needed airframe repairs that someone as detail oriented as Peter made the repairs.
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