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rmuell01
10-31-2012, 01:03 PM
Is there anything special about manufacturer Brass Drifts? Harder Brass (if there is such a thing), or type of Brass used? I've made some when I needed them. I was looking through some tool catalogs and I realized it's a tool I've never purchased?

thoughts?

Dr Stan
10-31-2012, 04:44 PM
There are different hardness-es of brass and it all depends on the alloy. Consult Machinery's or a good metallurgy text for particulars. Probably a good web site or two about the topic.

As to drifts, I assume you mean drill drifts. I've never seen a brass one, but that does not preclude their existence. On the other hand I've seen and used plenty of brass punches.

Peter N
10-31-2012, 05:06 PM
I understood perfectly what you meant Rob, been using Brass and Copper drifts all my working life. Never used a Brass punch though :D

It doesn't really matter what Brass you use, as long as it's softer than the object you're using it on, and it will work harden a little bit as well.
We've always used Brass & Copper drifts for tapping inserts and cores and core-pins out of and into plastic mould tools. Despite the fact that the steels are mostly 'hard' (anywhere between 35-55Rc) you can still bruise the fine surfaces a little using anything remotely hard, even mild steel. So brass drifts are perfect for the job.

Fasttrack
10-31-2012, 05:57 PM
As to drifts, I assume you mean drill drifts. I've never seen a brass one, but that does not preclude their existence. On the other hand I've seen and used plenty of brass punches.


I understood perfectly what you meant Rob, been using Brass and Copper drifts all my working life. Never used a Brass punch though

I assume he meant "drift punch".

e.g. http://www.sears.com/mayhew-3-pc-brass-drift-punch-set/p-00946515000P

Although I never understood how these "punches" picked up the name "drift". A drift punch is tapered and used for alignment. In my head, the only time a "drift punch" isn't a "drift punch" is when the term is preceded by "brass" :confused: :p Brass "drift punches" ought to be called brass pin punches...

e.g. a "real" drift punch: http://www.piehtoolco.com/contents/en-us/d1162.html

Peter N
10-31-2012, 06:53 PM
They look a bit fancy, we usually just hacksaw about a 3" length off from some 1/2" dia brass/copper bar and then hammer away. If we need it smaller then the end gets turned down a bit.
I'll get a picture of some well-used ones tomorrow:)

ikdor
11-01-2012, 03:25 AM
I suspect that the people that understand why they need a brass drift, are smart enough to find some brass stock. So I guess very few are sold :p

Igor

wierdscience
11-01-2012, 08:49 AM
I suspect that the people that understand why they need a brass drift, are smart enough to find some brass stock. So I guess very few are sold :p

Igor

Oddly enough until recently I was buying import Brass punch sets and using them for brass stock because they were cheaper.

They machined like Silicon Bronze though a bit tougher than 360 Brass.

Black_Moons
11-01-2012, 10:52 AM
Hate to hijack, but exactly how do you use a drift punch for aligning things?

rmuell01
11-01-2012, 11:03 AM
The English language is such fun. drifts, punch, drift punch, 1st definition, 2nd definition. In this case, it was meant to not deform the item I was trying to get out of the friggin hole.

glad to know there is a difference. Even the link to "Pieh tool" says "the traditional sense of the term" when they are referring to punches/drifts. So I'm going with the 1st definition of the term and not the 2nd definition which can be obscure.

and seeing that everyone understood, that means I'm communicating in a correct way.;)

LKeithR
11-01-2012, 12:26 PM
Hate to hijack, but exactly how do you use a drift punch for aligning things?

I assume what he's describing is what you would do when you line up the holes in two drilled plates with a tapered pin or bar. A tapered drift punch works in the same way.

By the way, I see you're in Mission--I'm just over in Langley--we should do coffee some day...

Fasttrack
11-01-2012, 12:36 PM
Hate to hijack, but exactly how do you use a drift punch for aligning things?

By conventional definition, a "drift punch" is a tapered "punch". For instance, I use them on a regular basis to install augers; the auger is a hollow pipe with flighting welded on it. They are connected to pulleys or each other by a solid rod that slips into the hollow pipe and is held in place by pins/bolts. You normally have to beat the pins in and sometimes the holes don't quite line up (e.g. the shaft needs to be rotated to match the holes in the pipe). This is a nontrivial task when you've used the BFH to get the pin in there. The solution? A drift punch! You poke the narrow end through both holes and then hammer away. The tapered nature of the punch naturally aligns the holes.

This works for two plates that don't quite line up and is also useful for expanding existing holes when smithing. (My soon-to-be-father-in-law is a farrier and blacksmith). Back when bridges and everything else were riveted, the rivet man would always have a drift punch with him (or her!) to align the holes before placing the rivet.

Black_Moons
11-01-2012, 12:58 PM
Ah, So my question becomes, Lets say you have two 1/4" plates, you just drilled a nice 1/4" hole through both. its not very well aligned so you jam the drift punch in and hammer(?) it some.

Is it designed to expand the first 1/4" hole so that the 1/4" thickness part of the drift reachs the bottom of the first hole and top of the 2nd hole? (Ie, so the plates are effectively aligned by a tapered pin in a tapered hole)

Or is it designed to just align the holes as best you can, with the 1/4" thickness part of the drift resting on the top of the 1st hole? (ie, the holes would still be out of alignment some, depending on how much it tapers down from 1/4" thickness along 1/4" of depth)

Or do you then pry on it, to align the last bit of the hole?

(Assuming cold mild steel, Not smithing)

Fasttrack
11-01-2012, 01:15 PM
Ah, So my question becomes, Lets say you have two 1/4" plates, you just drilled a nice 1/4" hole through both. its not very well aligned so you jam the drift punch in and hammer(?) it some.

Is it designed to expand the first 1/4" hole so that the 1/4" thickness part of the drift reachs the bottom of the first hole and top of the 2nd hole? (Ie, so the plates are effectively aligned by a tapered pin in a tapered hole)

Or is it designed to just align the holes as best you can, with the 1/4" thickness part of the drift resting on the top of the 1st hole? (ie, the holes would still be out of alignment some, depending on how much it tapers down from 1/4" thickness along 1/4" of depth)

Or do you then pry on it, to align the last bit of the hole?

(Assuming cold mild steel, Not smithing)

Let me preface this by saying that drifts are not used for precision alignment! This is for rough alignment to get a bolt, rivet, etc in place. I would classify this as a mechanic's or fabricator's tool rather than a machinist's tool.

Drift punches come in a range of sizes so the taper is fairly gradual. Combined with the fact that bolt holes have some clearance anyway, you normally only need to tap the drift in place. As you describe it: the 1/4" thickness part of the drift is resting on the 1st hole and the holes are still slightly mis-aligned (the idea is that the actual hole size for a 1/4" bolt is larger than 1/4" so you have some wiggle room). If the material is soft or if you really beat it, you will deform the metal and the result is a tapered first hole. Depending on the application, this may be acceptable. For instance, I can recall bolting stiffeners to grain bins where the drift punch was used to "align" the bolt holes. By "align" I mean one might have to beat the snot out of the drift punch to expand the sheet metal in a sort of oblong shape to get the bolt through.

Also, I often use the punch to pry but this is not a good technique. The punch was not designed to be used as a lever - they can bend!

Again, these typically only find use in "rough" work.