Tap burner, or extractors!!!!

[SydwazShawn]

Do any of you guys use those EDM style tap extractors, or burners for getting out taps? The ones I am talking about are like small table top machines. I am wondering if they work well and if there are any brands to get or not to get. I have a few Titanium parts that have been thrown to the side every now and again, and they might be salvageable if I can get the taps out clean.

 

Any help would be appreciated. Thanks, Shawn

[Greg_J]

Tap burners work well!

Speaking about the one I used, 1/4 and up to 3/4, no problem. It uses a deionized water and coolant mix, aluminum or copper electrodes. It'slike a straw for flushing. You adjust everything by hand and you'll need to watch that your centered on your tap so you don't burn your part. You have to play with the power settings, they have default values for certain sizes but you can tweek them to find what works, also when burning you can have problems burning your own swarf so make sure you have good flushing. When you find your sweet spot for the burn it will take only a minute or so to burn it out. Make sure you have a pick to gett the teeth out after your done burning, it's little to no effort.

 

Tap extractors are awsome, if you have a straight flute tap to work with, spiral flute won't work.

Also don't hit the tap with anything before you try to get it out or it will be inprinted into the threads and won't come out easy. Use tapping fluid if you have problems getting it out.

 

Greg

[SydwazShawn]

Do they make them for small sizes like 4-40? Also can they burn out blind holes.

[Greg_J]

I think any size electrode just it's harder to eyeball the location and you risk burning into your part.

[YoDoug®]

If you use the right size (a little undesize) electrode for burning a spiral flute tap you can usually get the tap out with a LH extractor then. Basically you want to burn a hole through the tap just a little smaller than the minor thread diameter. This always worked well for me in the past.

[SydwazShawn]

So you burn the center out, then there is an actual left hand extractor that is made for removing taps? I will have to do some more research on this it looks like.

 

Thanks, Shawn

[boneheaded]

The last place i worked before it closed we used disintrodes to burn out taps and drills. You get a chart for disintrode diameter, lbh-head vibrating settings, heat selection for taps from 0 to 1 1/2. q-head vibrating setting, drill size, disintrode diameter,heat selection for burning out drills from .040 to 1 1/2. Like someone mentioned above the hardest part of it is centering it so you dont burn your part. We only used copper disintrodes and the chart told you different size disintrodes depending on 2 flute, 3 flute and spiral for the same size tap because you are only burning out the center so the tap or drill will fall into pieces to be picked out. Yes you can do blind holes but as you burn your electrode gets shorter so you might have to do it twice after you check the depth of your first burn.

[MotorCityMinion]

We used em to burn out taps in engine blocks. 3.5 to 5." being the norm. They do work good.

[ktd]

We have a Sodick Cnc Hole Poper (small hole edm) It works wonders removing taps or broken screws. It will burn .007 - .118" dia. hole so it is purfect for small taps. If it a larger tap we just progam an aray of holes to burn the center of the taps out. Then we use a pick to remove the flutes from the threads. We have approx. a 99% success rate. The problems that we run into is that if people try to remove the tap with a chisel or punch before hand it make removing the flutes from the threads alot harder.

[Tap burner]

The tap burner works well to remove broken taps and bolts, the size of electrode should be half of the broken taps and bolts you want to remove, if you need, I could send you some pictures and video for reference.

[Newbeeee™]

^^^SHAMELESS PLUG

 

oh, welcome to the forum.

[Tinyfxds]

We had an old Milltronics VMC that we retrofitted with an EDM head.  It used brass electrodes that had a hole thru the trode for flushing and it spun as it burned thru the part.  The main reason we decided to retrofit this machine was to add wire start holes in our cavities but we quickly found out that it was great for removing taps as well.

[tiredtoolmaker]

On a different note, years ago, we tapped 10-32 holes in hundreds of thousands of titanium parts. Our now deceased NDT engineer came up with a mild acid mixture (customer approved) that dissolved the taps but had no effect on the titanium. We had a plastic vat that we lowered the parts in and several days later the taps were loose enough to remove with a pair of tweezers. This was a very inexpensive process.

[Gracjan aka Pullo]

I machine my taps out (HSS just to make sure ) on the same same machine the stuff is made. That is the fastest way . An example : M8 - I use a 6 mm end mill , revs about 4000 and now the most important thing , a small ramp motion of about 0.05mm/rev - feed maybe 200-400 mm/min . Should take about 3-6 min. If you are faster on the EDM + setup , EDM is the way to go

 

 

Gracjan

[Newbeeee™]

I machine my taps out (HSS just to make sure ) on the same same machine the stuff is made. That is the fastest way . An example : M8 - I use a 6 mm end mill , revs about 4000 and now the most important thing , a small ramp motion of about 0.05mm/rev - feed maybe 200-400 mm/min . Should take about 3-6 min. If you are faster on the EDM + setup , EDM is the way to go

 

 

Gracjan

We machine out but in handwheel mode.

2 flute carbide slot drill - 8 M/Min rpm and plunge with the tool offset from centre so it will allow the tap to fall 'inwards'.

Luckily we mostly cut ally and a bit of stainless...

[jlw™]

I'm going to look into tap burners. I've circle milled a butt load of broken taps.