mercoledì 26 novembre 2014

How to build a very cheap DIY tungsten sharpener / grinder

First thing first: I'm not dead, busy like hell for sure, but still alive nonetheless (well almost..); I hope this quick post, even if it's not strictly inherent with motorbikes will reassure everybody.. :)
Oh, and as you should have noticed by now, considering that there isn't much information about this stuff on the web (well, at least I did not find much..), I have decided that this time I'm gonna do something a little bit out of the ordinary, writing this post in English so that maybe it can be of some use even for some fellow oversea...
For those not so skilled with languages there are still plenty of pictures and the video, it should be more than enough to have an idea about what we are talking about...

Ok, now onto tungsten sharpener.. there are quite a few on the market, more or less portable, but all of them not very cheap (or really expensive in some cases). 
Let me clarify from the start that you can live and weld and prosper good without one, but there are cases in which one can be really useful, or even making a difference, or almost necessary. For example if you work in/for the food and pharmaceutical industries, where most of the stainless steel piping is welded by automatic orbital TIG welding, the use of a tungsten grinder to prepare the electrode for the welding machine is almost necessary.

There are still cases however where it is not possible to use an orbital tig welder, and you have to perform the weld manually, you have the grinder available and you use it to sharpen your electrode, and this is where you get used to the electrical sharpener and start to notice the difference in some occasions and start to want to have one...

The problem is that sometimes it can be difficult to justify to yourself the expense of about 500€ for such a device (unless of course you have already spended more than 30k for an orbital tig welder, in which case that should be a not concern..)

Considering that the more portable versions of sharpeners do not seems much more that a sort of dremmel-like rotary tool, that's exactly where I started from to build mine..

First of all I bough a couple of diamond cutting disks for the dremmel:

not exactly cheap compared to other accessories for this tooling, scoring at about 25€, but still manageable, and will last a lifetime before you have to replace it..

Than I built this concoction out of a piece of tube:

The slots that you can see at the top are of different dimensions, to accommodate different sizes of electrodes. If you want to be super-accurate you can drill holes of the right size at different angles, to have the choice of the final electrode point angle, as in the professional sharpeners.
I'm a lazy ass and this is one of those project that you want to have finished quickly to start doing some work on "something real", so I just cut them with an angle grinder and a cutting disk and call it a day.

On the bottom I welded a thick steel plate

drilled, and tapped a hole in it...

... the exact same dimension of the thread that you can find in the dremmel if you unscrew the plastic cap at the top.

Then it's just a matter of putting the diamond cutting disk inside the adapter...

... and screwing it on top of the dremmel...

There you have it, a nice, functional, portable tungsten grinder for less than 100 bucks (including the cost of dremmel - you can save even more you you buy cheaper brands)

To use it you just select the appropriate size slot, turn on the rotary tool...

... and rest the electrode on the bottom of the slot, letting it touch the disk. You can change the electrode point angle by changing how far you push it inside the adapter (the farther, the smaller the angle) according to suite your own personal taste or the particular job at hand.

Here you can take a look at a couple of different sizes freshly sharpened electrodes:

I've found that the portability of this kind of devices is a sometimes overlooked characteristic, and I've started to always throw it in my welding bag when I'm called to perform some in-site welding, because there are cases in which you don't have a bench grinder, or a belt sander, or even an angle grinder available, and by having the tungsten sharpener in my bag I can always count on a good, freshly sharpened electrode when I need one.

Here you can see the video of the cheap do-it-yourself tungsten sharpener / grinder in action:

Edit: after some months of use, the steel adapter started to eat away the plastic screw of the dremmel, becoming a little loose, so to keep it into position, I drilled and tapped some more holes around the circumference of the adapter, putting set screws into them, to firmly secure it on top of the rotary tool: