The price of Tungsten weights.

[RumRiverRat]

We all know how expensive tungsten weights are.

There is a very good reason why.

It is an incredibly difficult material to work with.

Incredibly dense and very hard.

I have been experimenting at work trying to machine some prototype weights in the hope of being able to produce them at a cost that would allow me to resell them.

My goal is to be able to sell at least 30% more weights for the same prevailing retail market price.

My conclusion has become it is not possible.

We machine a lot of Tungsten parts at work, so we end up with several 5 gallon buckets of fine tungsten chips every few days.

I asked the president of the company of I could have the buckets, since all we do is have a metal processor pick them up an he pays us a percentage of the money he gets.

So now I need to research how to melt tungsten and how well it molds.

If I can make it work, I plan on becoming a sponsor here and selling them.

Or it will fail miserably and I may have admit defeat.

[GooBack]

Google sintering.

Nothing wrong with admitting defeat now.

[Gordie]

Good luck RRR, but never admit defeat before you start as it it will lead you closer to defeat than success.

[CAMAN]

Tungsten comes as a powdered metal, that gets compressed and molded into shape and is considerably larger than finished size. That then gets placed into a sintering oven to a couple thousand degrees where it shrinks and becomes a solid. It is very difficult to machine unless you have diamond grinding wheels.

[Deitz Dittrich]

Good luck rat.. Keep us posted!

[HellaBass]

Definitely interested to see where this goes

[JP Z]

Just sell it in baggies as DIY kits. With no refunds of course.

On a serious note, I know one of the top lead workers in MN and they avoid it like the plague because of all the specialized equipment needed.

[Hester]

Diy kits.......that's funny.

[Ray Esboldt]

How about the tungsten pieces encased in some other material? Can you grind it into small pieces? Encased in plastic? Encased in lead - probably an issue in bonding the two materials or some other chemical reaction that I don't want to understand? Of course, if you do this you lose the best property of tungsten. It's feel while fishing it.

I hate to say it, but I love tungsten. Good luck with your project.

[CAMAN]

Yes you can mix it with some other material. Some manufacturers use tin and some use an epoxy or rubber. Yum made a line of tungsten weights (10+ years ago) that was a rubbery base with tungsten mixed in. You do lose a lot of the feel and density solid tungsten gives you. You will also have to figure out an economical way of turning your material into a fine powder.

Unfortunately you will probably never find an economical way to melt tungsten. With a melting point of about 6200 F. there are simply no "home sized" furnaces that will go that high.

Working with tungsten requires some highly specialized and crazy expensive equipment, which is probably the main reason only a few fishing companies market it.

BTW - If I may ask, what does your company make that they go through so much tungsten?

[RumRiverRat]

We make a rotor that is part of a mechanical gyroscope that is used to retrofit the Mk82 and Mk84 dumb bombs to make them slightly smarter.

All this technology is Vietnam Era,no longer used by the US instead it is exported to South Korea. Due to international arms export treaties the US is not allowed to sell current weapons technology to South Korea.

We use a basic 2 axis CNC Lathe to finish turn and bore the rotors, we remove a total of .030" from the bore and the outer diameter and .020 to .025" from the face of each part.

The rotor is tungsten because it is very dense, therefore very heavy for its size. Once another component called a rotor cup and rotor shaft assembly is pressed into the bore of the rotor a part called a drive cog engages the matching cogs on the rotor cup causing the gyroscope to "spin up" which activates the guidance system kit that is bolted on the Mk82 or 84 bomb.

This is nothing like the current GPS guidance used on JDAMs and other Precision Guided Munitions in the US Military's current inventoy.

I am waiting for a quote from our supplier, I used a 3D modeling program to design weights from 1/8oz to 2oz. The plan is to get rough blanks in and finish machine them like we currently do for the rotors.

If I buy in bulk 2000 or more blanks per size the material cost is not so prohibitive, based on the per blank price for rotors.

The key cost is the machine time involved.

We will see what happens.

[CAMAN]

Interesting, never would have guessed that answer. Thanks for sharing.

How do you plan on putting the hole in? Will the blanks have them already?

If you look at most standard carbide inserts for lathes and mills they normally come with no grinding or machining work done, only the high priced precision inserts get ground. So you can get decent finishes from sintering and include the hole. If that is what your supplier is able to do you shouldn't need any finishing processes other than paint.

[RK]

If you can figure out an economical production process, that'd be something.

I forced myself to pretend to be a skeptic about tungsten weights even though I knew better. Then finally tried them and went "Awww, shoot. These things are great..." I cringe every time a pike bites off a Texas rig...

[RumRiverRat]

The blanks will have a rough hole through them. Based on how the blanks for rotors look, Finish machining will be necessary.

I plan on clamping on the rough OD, the blanks will be .080"to .100" longer than needed. Finish turn the OD and ID so the are concentric.

Next Op would clamp on the finished OD, face off the excess material and put a spherical radius on the back side so the bait fits nicely.

The through hole will be bored with a custom made boring bar, it is a tool we currently use to bore a very small hole in a part that is made out of a double drawn Tool steel HRC 60.

[Cecil]

[Deitz Dittrich]

MmmmmMMmmmm Pancakes.

[RK]

MMmmmmmm.....bunnies

[Gordie]

Add bacon and MMMMMMMMMMMMMMMMMMMMMMMMMMMMMM

[tolle141]

What about melting the shavings in glass? Keep the feel and finding glass is pretty easy

[mww24]

Good luck RRR.

[Hawg]

Best of luck but this is justifying why they are so expensive. Tingsten is tough to work with because of the super high melting point and the equipment it take to machine it. I'll take a bunch if you do figure it out though.

[MN BassFisher]

This post has taken a turn and now made me hungry. But back to the OP - goodluck with that. If you get the process down, I'll order a handful!

[RumRiverRat]

I have sample blanks in my possession.

Just need to find a spare moment or 2 to machine them.

Have worked 17 days straight and all but 8 days so far this year.

18,000 total machine hours backlogged at work right now.

[fishinggeek]

I'll stick with getting the size and shape I want at the store. Sorry man but I have a feeling it's not going to pay out that much for how much time and work that is put into it.

[MyFishHasRabies]

Wow. When I read the OP, I never thought it would end with

I have sample blanks in my possession.

Props. Good luck. I'd like to know how they perform.