The Big Ugly Tool

[Reed Gray]

Well, I have talked about it a lot, now, here is how to make one. I will film another one about this tool and feature a master of it, probably later in the year. Just another scraper to me.

https://www.youtube.com/watch?v=orV-Oi5UsSo

robo hippy

[Dok Yager]

Love the DIY factor. Unique way to make a scraper.

[Thom Sturgill]

I was concerned about heating the metal to cherry red and looked it up. Asteg.com says the following:

... In addition, it will not anneal or lose its cutting edge as will H.S.S. when subjected to high-red heats generated during the cutting cycle.

Tantung G is recommended for general purpose machining of both ferrous and non-ferrous metal and general woodworking operations. For catalog items, Tantung G Hardness is 60 to 63 Rockwell C...


So no damage to the metal with the acetylene torch. I took a silversmithing course many years ago, and remember that silver solder comes in different heat ranges which were referred to as hard to soft. This is needed so that pieces can be built up in stages without de-soldering prior stages. We used acetylene, but NOT oxy-acetylene. Not quite as hot, but hot enough to silver solder. Also we applied the flux as a liquid if I remember correctly.

[Reed Gray]

Randal had a very old jar of flux that had dried out. Talked to the welding shop, and the paste/liquid form is water based, so crumbling up the chunks worked fine. Paste might be easier to spread.

robo hippy

[David Gilbert]

I watched the video and found it very interesting. At one point you make reference to how it will be ground back with use. What system do you use to sharpen the big ugly? Can you sharpen tantung with a CBN wheel.

Cheers,
David

[Reed Gray]

Tantung sharpens easily on standard aluminum oxide wheels, and CBN. I do relieve most of the heel on the bevel since the lower part is softer steel, and can load up your CBN wheels. I haven't had any problems with it loading as the Tantung will take most of the loading off, and a standard scraper does the rest.

robo hippy

[Jeramie Johnson]

Great video Reed. Thank you for doing this. Looks like I will have a couple more requests of my brother-in-law.

[Rob Grindler]

Two questions ,where can one buy tantung? And can you weld the tantung to the bar,with a mig welder or arc welder?

[Reed Gray]

Rob, I have a video on making the Big Ugly up on You Tube. You have to use silver solder ribbon rather than welding or brazing, which I am told is best for metals that are not similar. PM sent...

robo hippy

[Dwight Rutherford]

I am interested in a source for the tantung also. Thanks

[Bob Fogel]

What is silver content of the silver solder you used?

[Brice Rogers]

Bob,

When I silver solder things like bandsaw blades, dissimilar metals and things that cannot take the temperature of welding without severe distortion, I use an alloy from Harris of 45 percent silver. I bought it from a welding store. It is very very strong. Here is what Harris said on their website: " Safety-Silv® 45 Description: General Purpose Silver Brazing Alloy. Excellent general-purpose brazing alloy. Often specified in government use. Good ductilitiy and capillary flow. Color is silver to light yellow."

It flows like water when at the "liquidus" temperature. But hard silver solder come in silver concentrations from about 25 percent to about 56 percent and there are a dozen or more special alloys for unique applications.

The surfaces need to be very clean (e.g., no finger print oil) and fluxed. You only want to get the flux up to the melting temperature of the silver solder. In my case, that's about 1370 degrees F. Or roughly red in color. If you overheat it, you can burn the flux and interfere with the soldering process. If I were trying to make a big Ugly, I would probably take the silver solder wire and flatten it a bit with a hammer to make thin ribbons or a flattened serpentine. (SS can also be bought in ribbons). I'd flux the two metals and place the SS ribbons between the two pieces. Then heat the assembly until I see the solder flow. As soon as it flows, then remove the heat. That is what I do with SS scarf-joints on bandsaw blades and I have never had a scarf-joint failure. I have had better control and absolutely no flux burning doing that as compared to adding solder to the bare joint. Perhaps on the latter I have a poor technique.

On bandsaw blades I can silver solder with a propane torch. But if I was trying to do a Big Ugly, there is going to be a lot of heat conduction and dissipation - - I would need something hotter, like oxy-acetylene.

[Steve Nix]

I purchased my tantung g on eBay.

[Reed Gray]

I can't remember exactly, but 55% or 50 some thing.

robo hippy

[Bob Fogel]

Thank you for the very informative answer. I use oxyacetylene but need to order solder.


Bob,

When I silver solder things like bandsaw blades, dissimilar metals and things that cannot take the temperature of welding without severe distortion, I use an alloy from Harris of 45 percent silver. I bought it from a welding store. It is very very strong. Here is what Harris said on their website: " Safety-Silv® 45 Description: General Purpose Silver Brazing Alloy. Excellent general-purpose brazing alloy. Often specified in government use. Good ductilitiy and capillary flow. Color is silver to light yellow."

It flows like water when at the "liquidus" temperature. But hard silver solder come in silver concentrations from about 25 percent to about 56 percent and there are a dozen or more special alloys for unique applications.

The surfaces need to be very clean (e.g., no finger print oil) and fluxed. You only want to get the flux up to the melting temperature of the silver solder. In my case, that's about 1370 degrees F. Or roughly red in color. If you overheat it, you can burn the flux and interfere with the soldering process. If I were trying to make a big Ugly, I would probably take the silver solder wire and flatten it a bit with a hammer to make thin ribbons or a flattened serpentine. (SS can also be bought in ribbons). I'd flux the two metals and place the SS ribbons between the two pieces. Then heat the assembly until I see the solder flow. As soon as it flows, then remove the heat. That is what I do with SS scarf-joints on bandsaw blades and I have never had a scarf-joint failure. I have had better control and absolutely no flux burning doing that as compared to adding solder to the bare joint. Perhaps on the latter I have a poor technique.

On bandsaw blades I can silver solder with a propane torch. But if I was trying to do a Big Ugly, there is going to be a lot of heat conduction and dissipation - - I would need something hotter, like oxy-acetylene.

[Rick Markham]

Awesome video Reed! Good to see you! This looks like a cool project, thank you for taking the time to film and post this. I will definitely be trying this in the future.

[Mike Goetzke]

Don't know if this is where Robo gets his but found it on the internet: http://vrwesson.com/products/tantung

[Bob Bouis]

So I tried to make one of these. I don't have an acetylene torch, and I knew there was no way I'd get it with a copper sweating handheld, so I tried to do it with one of those $15 weed burning propane torches from harbor freight. Claims to put out 500,000 btu/hr so I figured it was worth a shot. 3/4"x1/4" bar stock. 45% silver solder. Brazing flux. 1/8"x3/4" tantung.

Did it work? Kind of. I built a small "forge" out of concrete blocks, clamped the bar in a vise, shoved the torch in front of it, and let her rip.

Unfortunately it was rather cool and windy outside and that dissipated the heat quickly. The long bar and the vise didn't help either. Ultimately I was only able to really heat the tantung bit, and not nearly as much as in the video. A dull red only. But did the solder flow? Yeah! Unfortunately my driveway is sloped and I failed to re-level it after moving the apparatus into place, so it flowed down and the solder is thicker on the end. It also didn't really make it all the way to the edge on one side. But the bit is pretty darn attached. I think, at least. It looks terrible, and there's little or no solder for the back 1/2" or so, but hopefully it'll work okay. I hit it with a hammer as hard as I dared (I don't think tantung is very tough) and it stayed on.

I think if I'd been using a 5/8" bar and had done a better job of prepping (no vise, cut the bar ahead of time, better kiln), it would have worked out fine. I was actually going to re do it but I ran out of propane (didn't start with much). Also, it cracked all the concrete blocks, so don't do this with blocks with sentimental value (or any other value).

356371

356372

[Reed Gray]

I can't tell you if it will work or not. They do say that you should use the thick 50+% silver solder ribbon. I did put one on with JB weld. The CBN grinding wheel didn't like that, and it eventually fell off.

robo hippy

[Bob Bouis]

Thanks for the input, Reed. Like I said, it seems to pretty stuck on there. Will it last? I consulted a guy who works on stuff like this for a living. He said "try it and see." He said the 45% solder should be fine, and that only requires a dull red glow rather than a hotter cherry red. But apparently you're supposed to get both pieces equally hot in order to get a reliable bond. I got the steel bar pretty hot, but it didn't glow much, at least not more than an inch or two in. Ah, well. I still have the other half of the tantung stick, plus I can remake this one if it comes apart. I should have just taken it to somebody, not that hard to do. It might work out, but I'll report back if it doesn't.

[Reed Gray]

I think with the original ones, they wanted the thicker ribbon to cover any potential voids. Two pretty dead flat surfaces should be fine. With a torch, you can heat it back up and then put it back on again.

robo hippy

[Bob Bouis]

Well, that was quick. I cut the bar and when I'd ground about 90% of the tang, the tantung just fell off. Not sure if it was the heat or the vibrations (or both) that did it.

Looking at the solder, it looks a bit thin, so I'm going to add some and redo it. It seems like nobody has a torch anymore, though. I guess I could take it to a muffler shop.