Drilling Out Aluminium Pop Rivets

[castlemaine]

I've been trying to drill out Al pop rivets to replace some press studs for the storm cover.
Half way there but my drill bit tends to spin rather than bite straight into the rivet, so it seems to take some time to get a rivet drilled out.
I am using an all round drill bit. Am I better off using a metal bit or something else or is there a trick to this? I was told to keep the drill bit wet with WD40 (Fact or Fallacy?).
Cheers8-)

[alcam2001]

Not sure if you mean that the rivett is spinning or that the bit is jammed and the chuck is spinning on the bit.

Anyway..... try hard to use a bit the same size as the rivet - only go up a 1/2mm if you really have to and be very careful not to enlarge the hole (unless that is not a problem). Remember 3mm rivets are about 3.2mm and are actually 1/8" (nearly always) - so get a 1/8 bit for them, or a 3.5mm one, with a regular metal drill tip. Also, easier to use a proper rivet hole bit - can work both ends, shorter and less likely to break in the hole due to less protruding bit, and the chuck is holding the bit shaft, not the twist part of the bit.

When drilling out the old rivet, do as above - and push hard at medium speed straight away. the longer/gentler you go on, the more likely to enlarge the hole, slip the bit onto something you dont want scratches on, spin the rivet without getting the head off, and blunten the bit (a signifcant factor if you are drilling out thousands of them - though not a problem for a bimi !!). Whe the head is off, it is usually better to use a punch to push the rest of the bit out, since continued drilling could cause other problems or encounter a metal bullet in the rivet. Careful not to

If you do get a spinning rivet, then you just need to push really hard to get it to lock for long enough to rip the head off.

I use silicon grease, cutting oil or wd40 for drilling holes in metal (or hardwood) but I have not tried those for drilling rivets out - seems getting something slippery into the mix could just make some new problems - including spinning the rivet. No doubt other people use them effectively.

Alum rivets are so soft that they should not cause you any problems when you get it sorted.

Good luck !

[trueblue]

a 1/8 rivet is always 1/8"

never seen a 3mm rivet..............

[oldboot]

I've had plenty of practice drilling out rivets.

Remember blind rivets are neither metric nor imperial fractional sized......if they are standard and compliant ( most are) the correct size coresponds to number drills....from memory a so called 3/16 or more correctly #6 rivet coresponds to a #30 drill (don't trust me look on the box) some rivets you will get away with imperial fractional drills.

One of the big problems with drilling out aluminium rivets is the steel mandrel that remains inside....if there is somewhere to drive the mandrel too.....use a pin punch and drive the mandrel out before you start drilling.

some times you have to drill a bit before you can drive the mandrel out.

Rivets will often spin anyway especialy if the havn't poped off properly.

diving them a smack on the head with a hammer backed up with a dolly can work.

sometimes you just have to butcher it out by tilting the drill.

sometimes you can get a screwdriver under the rivet to hold it while drilling

somtimes after drilling you can cut the head off with a sharp wood chisel ( not your best) and drive the rest out the other side with a pin punch or have another go at drilling.

remaking stuff that has been riveted together can be a real fiddle, especially if the rivet is in a blind channel or into solid.....you may have to be persistent, inventive and carefull not to butcer the job.
Sometimes you just have to make a mess and go up a size.

Now.....remember if you are using aluminium rivets with a steel mandrel, in a marine situation, it is wise to drive the steel mandrel out of the rivet after you pop it off.....then fill the hollow ith sicaflex or similar......this will reduce the corrosion problems due to the steel.

If you are realy fussy....put some duralac on the rivet before you put it in.

cheers

[Roughasguts]

Trouble is if you drive the steel mandrel out of an aluminium rivet, the rivet will not hold as tight will get loose and then pull out.

On the other hand if you leave the mandrel in, the aluminium will corode get soft the mandrel will fall out and then so will the rivet.

cheers

[Popper52]

Hi,
if you are drilling out a 1/8" rivet use a No.30 drill bit,(number drill) you can get these as a double-ended drill bit for abou $2.50- $3.00 a pop from local hardware/Bunning? whatever.
If you put a small centrepunch mark on the outside of the rivet , half on the rivet and half on the material the rivet is in, it will help to stop it spinning (sometimes)
Hope this helps,
Rog.

[PinHead]

simple..just drill it at a slight angle..never fails.
don't use WD40 or anything else. Bit at slight angle..high speed...that is why they are called high speed twist bits.

[greenie61]

Rotate the drill on a slight angle (slow drill speed) when you first start to remove the head of the rivet only, Do this slowly so as the press stud doesn't spin & mark the boat then just push it in straight to remove the rest.

Rivet size should be 73-AS 4-4 to 4-6 depending on grip range. Do not use any larger rivet or the female wont fit & clip on.

Been doing it this way for 30 years.

Mark

[castlemaine]

And I thought a pop rivet was a pop rivet ;D

Sorry I didn't make it clearer, the press-stud and rivet is not spinning but I've been holding the drill directly into the rivet, but the drill bit takes a while to bite, I'll will give it a go at an angle, as suggested.

Been doing it to apply duralac on the new ones to reduce corrosion.

Cheers8-)

[ric]

And I thought a pop rivet was a pop rivet ;D

Sorry I didn't make it clearer, the press-stud and rivet is not spinning but I've been holding the drill directly into the rivet, but the drill bit takes a while to bite, I'll will give it a go at an angle, as suggested.

Been doing it to apply duralac on the new ones to reduce corrosion.

Cheers8-)

there is some excellent advice here but i think its as simple as getting a decent drill bit. check the drill is spinning clockwise and that the drill bit cuts clockwise too. - maybe just buy a new drill bit that is sharp.

Ric

[STUIE63]

the proper name for the double ended drill bits to suit rivets is Tupoint and they are available in 1/8" #30 #20 #11 gauge sizes . having the right name will help when trying to buy a new drill bit .

[oldboot]

The double ended jobbers of whatever brand name are great stuff, the cutting angles are different and they are harder, they make a cleaner hole and all being well a pretty clean exit on the other side.

But no matter what drill you use, if the mandrel spins, or the very tip of the drill is not 100% progress stops, no amount of jiggleing or twisting or side drilling will help. so ya have to try something different.

If you are doing a rework in the same holes ya realy want to go down the centre of the rivet as clean as possible so you don't enlarge the hole.....driving out the mandrel first is definitely the go.

I used to build equipment cases and I have built cases that took over 500 rivets ( thank god for air riveters), when you stuff up or have to rework a case to make alterations, replace broken catches corners and handles ya get pretty damn good at removing rivets ( a handle has 10 rivets, catches likewise have 10 and corners have up to 6

If you have to replace catches handles and corners on a large case that is a lot of rivets to replace..and ya cant afford too many oversize holes or the case goes together poorly.

most rivets come out pretty easy.....but ya always get the odd mongrel rivet that don't want to come out.

I have not seen a rivet come lose because of the mandrel being removed.....in fact if the rivet is poped off at ideal depth the mandrel will drop out.

BTW... all rivets aint "pop" rivets.....only the "Cherry" brand.

There is quite a bit of variation between brands.
Some of the brands the rivets are a close tolerance fit into a number drill hole and they will not go in easily in a fractional drill hole, others go thru a fractional hole quite well and there is some variation in material depth that the rivet will pop off in, between different brands.

cheers

[Mudlicker]

the proper name for the double ended drill bits to suit rivets is Tupoint and they are available in 1/8" #30 #20 #11 gauge sizes . having the right name will help when trying to buy a new drill bit .
Nice work Buddy , thought i would see u answer this one ;)

[mitchdemeanor]

Cant say i've ever had a severe problem with drilling rivets. No "special" bits are really required, just a good 1/8 hss bit should do the trick for a 3.2mm rivet or a 5/32 for a 4mm, should be the only sizes i would imagine you would encounter.

If you are still having problems maybe try some screw wax on the drill bit, i often use this when i'm drilling thicker aluminium as it will still give you cutting power while at the same time preventing the drill bit from overheating

[Getout]

I work with rivets and I NEVER drill them out. There is too much risk of enlarging the hole. Best way is to use an oversize drill bit to partially drill and spin off the head, then use a pin punch to punch the stem thru. If the head spins without breaking off, use a sharp cold chisel to knock the head off and then punch thru.

[fairpractice]

hi "getout" is spot-on. reduce the "head" with LARGE drill and punch out. good luck.