[av8or1]

Ok I just called the local store. And yup, they have it in stock. So much for doing my part to shelter in place and order everything online. Gonna pop down there tomorrow to pick one up I think...assuming that they will accept cancellation of the online order and refund my card. TBD.

[DavidR8]

Ok they just called. And yup, they have it in stock. So much for doing my part to shelter in place and order everything online. Gonna pop down there tomorrow to pick one up I think...

I'm definitely curious to see how this works out for you.

[BillE.Dee]

I do have one of those lil 3 inch bench grinders by HF and use it all the time for tungsten sharpening - DEDICATED. The motor won't produce a lot of power but enough to do the job.
I did notice that the wheels do NOT fare very well to the tungsten but I picked up an extra set of wheels for that machine. I took off one of the wheels and installed a "polishing" wheel for final touch up and it also does not fare very well against the tungsten. The retaining nut on the left side is LEFT HANDED. Just get an extra set of wheels,,,you'll be good to go for a year or so on one set.

[av8or1]

Thank you for the feedback BillE. Although your configuration was admittedly not clear to me.

The approach that I will take to this involves a slight modification to the configuration in which the HF min-grinder comes out-of-the-box. Specifically, it has an 80 grit grinding stone and a cotton buffing wheel. My initial plan is to remove this grinding stone and replace it with a 3" diamond grinding wheel that I sourced from Amazon. I chose 150 grit but there are others available. I'll attempt to use the existing cotton buffing wheel, but if it won't hold up then I'll investigate other options. Not sure what Oscar uses, but he did mention that he uses this mini-grinder to buff/polish his tungstens.

The possible issues that exist with the plan are:

1) Some of the reviews of the diamond grinding wheel indicate that it is not 3" but rather 3.09". This difference causes it to not fit the mini-grinder. It wasn't clear if the inability to fit was because the cover won't fit back on once the diamond wheel is installed or if the diamond wheel won't even fit into the housing. That is TBD.
2) The other point of contention was in regard to the arbor size. The mini-grinder manual states quite clearly that its arbor size is 1/2". The aperture of the diamond wheel is also listed as 1/2". However there have been reports that the diamond wheel's aperture is actually a little larger than 1/2" and thus you need a bushing to make it work. That is also TBD.

So those are the two issues that I'll be investigating. I'll report back when I know more. I called HF this morning to cancel the online order of the grinder. The rep stated that it might ship prior to the cancellation being processed. Wha-? Why is everything SO slow with HF? However she said that I could refuse it if that happens. 'Problem with that is that I live on acreage so the delivery companies leave our stuff in the delivery box, ergo, no opportunity to refuse anything really. I'll cross that bridge when-and-if it comes 'round. Anyway the point being that I am headed to the local HF this afternoon to pick up a mini-grinder in person. Thus I should have an answer to these questions tonight. TBD.

And of course this will be a grinder that is dedicated to sharpening tungstens exclusively. I know enough about TIG welding to know that such a provision is a must if you want to have contaminant-free (or as close as possible to that anyway) tungstens after sharpening.

Thanks!

[av8or1]

Alright so the grinder business is taking on a life of its own...wouldn't ya know it. I should have a report ready by tonight, presuming that family stuff doesn't intercede...

In the meantime I'd like to pose a question: Oscar made mention of using an Aluminum Oxide wheel on his grinder to sharpen his tungstens. My question is whether or not that would contaminate the tungsten if you were welding anything other than aluminum?

I suppose that the question I have is why opt for an aluminum oxide wheel over a diamond one?

Thanks!

[Oscar]

Check PM's.

[av8or1]

Alright, so as I mentioned this endeavor to source a relatively inexpensive means of grinding tungstens took a deeper dive than I had anticipated. However in the end such effort would produce a good result: I found a solution that will serve me well. Or at least it seems like it will to these still-new-to-TIG eyes. And sense.

But I'm getting ahead of myself a bit. First, know that this solution will run you right around $60, give or take a few. Given some of the options I looked into, this was a much more favorable result for me. Granted, I did spend more than that in order to test and arrive at the end-solution, but I anticipated that. The good news for the remainder of you is that if you follow this approach, it'll just run you the $60. I was the test pilot on this one, thus the additional cost (which was not much).

And with that, I'll commence the report of what I developed. For some of you this may be a bit of a yawn-fest, but for someone who is just starting out in the TIG world, this will likely be of benefit. So here we go...

[av8or1]

So what was the additional cost you ask? Well in the end I purchased two grinders. But as usual I'm getting ahead of myself. This was the first one:

grinder 1.jpg (44.41 KiB) Viewed 1898 times

It is the Harbor Freight Chicago Electric 3 In. Mini Tool Grinder With Buffing Wheel. SKU #94071. This was the grinder that I had originally planned on using. Note that by the time I snapped the above picture I had removed the side walls of the wheel housing. Ergo, it doesn't come in the configuration shown above out-of-the-box. On the whole, it met expectations, though somehow it was "just smaller" than I had anticipated. As in "way smaller". Don't know how that happened but ... anyway. So I powered it up to verify operation. It was relatively quiet. The shaft however was a tad concentric and thus the rotation was not uniform about the lateral axis. Both the stone wheel and the buffer wheel had lateral movement which contributed to a slight vibration and a tad of noise. However given the cost and source this was not unexpected. Thus I'd have to say that, again, this product lived up to my expectation.

The first thing I did was to remove the stone grinding wheel:

grinder 2.jpg (67.88 KiB) Viewed 1898 times

It appeared to be of ok-to-decent quality. Thus no complaint there.

[av8or1]

The second thing I noticed about this grinder was that the actual arbor is not 1/2" as stated in the product listing. If you attempt to mount a wheel with a 1/2" aperture onto it, it will be noticeably loose. And of course it will not spin in that configuration. However I noticed that both the grinding stone wheel and the buffing wheel both had a bushing installed. Those bushings were plastic and appear thusly:

grinder 8.jpg (54.25 KiB) Viewed 1898 times

grinder 7.jpg (38.98 KiB) Viewed 1898 times

I was kinda disappointed in that, if to speak openly. For that reason, I didn't bother to measure the diameter of the actual arbor; I chose to just move on. I reminded myself that this was/is a tinsy-sized grinder, "so what do you expect"? That didn't help, but it sounded good.

[av8or1]

I then compared the stone wheel to the diamond wheel. There is a width difference:

grinder 3.jpg (40.89 KiB) Viewed 1898 times

And as one of the reviews for this diamond wheel indicated, it is a tad larger in diameter than the stone wheel that comes with the grinder:

grinder 4.jpg (67.23 KiB) Viewed 1898 times

[av8or1]

So I decided to see just how much bigger. First, the stone wheel came in at 2.945":

grinder 5.jpg (56.36 KiB) Viewed 1908 times

While the diamond wheel measured at almost exactly what the review stated (which was 3.09") but just smidge-tad-itty-bit smaller at 3.074":

grinder 6.jpg (61.67 KiB) Viewed 1908 times

This difference did augment the grinder's overall noise signature with that of the diamond wheel cutting into the housing. However once it found its way, that noise subsided.

Generally speaking I was not impressed with how this was going, but ... considering the cost it was on-par with my "realistic-ized expectations".

[av8or1]

That said, I decided to press ahead with the investigation. I installed the bushing from the stone wheel into the diamond wheel:

grinder 9.jpg (209.84 KiB) Viewed 1907 times

Since the diamond variant is narrower than the stone one, that resulted in a bit of stick-out of this bushing:

grinder 10.jpg (31.33 KiB) Viewed 1907 times

Which was disappointing too, but I knew from having taken a look at the outer flange that due to the shape of that flange, this stick-out wouldn't be an issue. And sure enough, it wasn't. Wiping the eyebrow on that one.

[av8or1]

Here is how the pieces-parts fit together then, from left-to-right in the picture and from inner-to-outer on the grinder:

grinder 11.jpg (61.01 KiB) Viewed 1905 times

Spacer -> inner flange -> bushing/wheel -> outer flange -> retaining nut (10 mm)

Ok. Hmmmmmm...I had everything assembled. I took a step back and looked at the result thus far. Something wasn't appealing about it to me. However I decided to set that aside for a minute and verify that it would run with the diamond wheel. I powered it and sure enough, it ran just fine, with no additional noise or vibration than that which I experienced when running with the stone wheel. So I powered it down and took another look.

That's when it dawned on me...

There was/is almost no space between the diamond wheel (or the stone one for that matter) and the housing. Thus it would not be possible to place your tungsten on the top of the wheel when you attempted to grind it. And the distance between the top and bottom of the opening in the housing wasn't all that big. "Huh. Hadn't thought about that 'til now" I said to myself. So what did that leave then? Well, you'd be required to place your tungsten at an awkward angle, either high or low in order to grind it; choose your poison. Thus:

grinder 12.jpg (209.42 KiB) Viewed 1905 times

[av8or1]

And since you need to put your tungsten into a drill if you take this approach to sharpening it, that would mean that you'd need to assume an awkward position indeed. I suppose that if you rotated the grinder 90-degrees backward about the lateral axis (ergo away from you) and mounted it like that, then it might be possible...yeah.

So that was it for me. I'd had enough by this point. This approach was simply not able to bear fruit; at least for me it wasn't. Disappointing, definitely, but hey, it happens. Keep at it, right?

Well then. Having arrived at that decision, I decided to consider other options. As I mentioned several posts ago, I cancelled my online order of this grinder (and BTW it shipped before HF cancelled it, so I'll have the joy of returning it to the store ... yay!) and proceeded to just pick one up locally. Anyway, while doing that I had taken a quick peek at the other grinder offerings that HF had on-hand. Most of them appeared to have "more room" between the wheel and the housing. I didn't think much of it at the time, but after seeing this result, it was on my mind now.

And with that I returned to the local HF store to take a closer look. As it turned out, there was a 5" grinder that was the identical price of the 3" critter. Thus:

grinder 13.jpg (75.72 KiB) Viewed 1902 times

grinder 14.jpg (66.08 KiB) Viewed 1902 times

The 5" offering had a larger gap between the wheel that comes with it and the housing. Not significantly larger mind you, but larger such that you could fit a tungsten between the two. For that reason as well as the identical price, I decided to take a punt on it.

[av8or1]

So this particular grinder product is titled CENTRAL MACHINERY 5 In. Bench Grinder, SKU #94186. Because Oscar had mentioned that he uses an aluminum oxide grinding wheel and there was a 5" one displayed just above the display model, I decided to take a punt on that too and bring one of those home as well:

grinder 15.jpg (202.4 KiB) Viewed 1900 times

Heck why not? I had a coupon but it wasn't applicable to any Central Machinery product, so I wouldn't be able to use it otherwise.

Anyway, the 5" is larger, obviously, but somehow it was the size I had envisioned for the 3". Funny that. Anyway:

grinder 16.jpg (63.44 KiB) Viewed 1900 times

[av8or1]

The retaining nut for the 5" grinder was of a respectable size and more to my liking at 17 mm:

grinder 17.jpg (228.62 KiB) Viewed 1898 times

And unlike the 3" grinder, the arbor on the 5" variant was indeed 1/2". Thus no bushing needed. That too fell into the preferences column for me:

grinder 18.jpg (224.95 KiB) Viewed 1898 times

[av8or1]

I had considered purchasing a larger diamond wheel for this new grinder. 'Even did a 2-minute Internet search for them. However it occurred to me that there wouldn't be any reason that the 3" diamond wheel wouldn't run on the 5" grinder. With that I immediately thought "so why bother? Just run the 3" one." And as fortune would so have it, that would be a good choice. Well, good for me anyway.

So I removed the diamond wheel from the mini-me 3" grinder, removed the plastic bushing, re-installed that onto the stone wheel and returned the 3" grinder to the configuration it came in. I then mounted the diamond wheel onto the 5" grinder - and it was oddly refreshing that no bushing was needed - and secured it with the retaining nut. I reinstalled the housing side wall/cover and this was the result:

grinder 19.jpg (49.76 KiB) Viewed 1896 times

grinder 20.jpg (210.18 KiB) Viewed 1896 times

Which admittedly looked rather strange upon first glance. However when I considered that there would be way-ample room to fit your tungsten in-between the wheel and the housing, thus eliminating the awkward angle with which you'd need to hold the drill...well suddenly that picture seemed much more attractive to me.

And so I decided to give it a test run...

[av8or1]

Pictures of the gap between the diamond wheel and the housing, as well as the more favorable drill-holding angle:

grinder 21.jpg (206.05 KiB) Viewed 1895 times

grinder 22.jpg (61.05 KiB) Viewed 1895 times

[av8or1]

The result was, to my inexperienced TIG eyes anyway, exactly what I would expected to have seen once a tungsten was properly sharpened. The 1/16" rod:

grinder 23.jpg (61.59 KiB) Viewed 1894 times

And the 3/32":

grinder 24.jpg (61.6 KiB) Viewed 1894 times

They were sharp enough to pierce my skin when attempting to take the above pictures, I didn't see any weird grain patterns and in fact those patterns matched what I had seen depicted as being the goal when doing this sharpening thing. For those reasons, I viewed this as a success. I attempted to take even closer pictures to offer for consideration, but the focus on the camera phone wouldn't cooperate, so...

[av8or1]

And so there you have it. That is my report. And this is the means by which I will sharpen my tungstens. It is inexpensive, simple to configure and (seemingly) will last quite a while prior to needing replacement. Therefore, based on my quite limited TIG experience, I give this my recommendation. I might not have done much TIG stuff yet, but I do know fabrication and metal, having done lots of MIG and stick over the years. So there's that.

Anyway, open to feedback.

Thanks!

[DavidR8]

Thanks for the detailed write-up.
Looks like a good solution if not slightly annoying to achieve.


Sent from my iPhone using Tapatalk

[cj737]

The picture of your 3/32 tungsten shows a rather thin, elongated tip. Be aware, if you use that tungsten on higher amp welds you run the risk of that tip severing and becoming embedded in the weld. A major no-no for important welds.

This is a result of too flat a grind angle which is common with handheld grinding. A good and simple remedy is to fab up a small plate that allows you to align the tungsten to the wheel at your desired angled for consistency. It will also avoid grinding beyond the tapered shoulder. (Happens when you push in too far).

Grinding tungsten is an obsession to get them “just how you want” reliably. A bit of upfront effort and you can produce a setup to yield the results you seek.

[av8or1]

Thank y'all for the feedback.

I agree with ya CJ, the angle that I produced on the 3/32" was too shallow. However that was neither intentional nor random. I was experimenting with different angles of holding the drill in order to see what would be required to produce either a shallow or steeper angle. The first of my grinds on both rods were indeed steeper in angle. I then wanted to see what I needed to do to produce a shallower one if I was planning on attempting a lower-amperage TIG weld. And I was able to figure that out. As it just-so-happened, that is where I decided to stop, thus the picture.

The main objective of this endeavor wasn't to become experienced with how to grind tungstens. That is the next step. Rather this "research" was aimed at merely developing a means by which I could do it at all. And do it inexpensively. That much was accomplished, so thumbs up.

As for your suggestion of creating a plate to get a desired angle consistently, that's a terrific idea! I'll have to look into that, thanks!

[Poland308]

When I don’t have a fancy grinder to use, I tend to grind so that the distance from the tip to the end of the grind is about 3 times the diameter of the tungsten.

[Oscar]

Not sure what Oscar uses, but he did mention that he uses this mini-grinder to buff/polish his tungstens.

This is the grinder I use:

https://www.harborfreight.com/bench-gri ... 43533.html


So what I do, is for sharpening new 1/16" tungstens and touching up larger tungstens I use this, as well as polishing all tungstens. For getting the initial grind on 3/32"+ tungstens, I use a 6" bench grinder with a standard (rough-ish) aluminum oxide wheel to remove material fast.