An alternative to the ultimate bucking bar?

I can't help be a bit envious when I look at the "new" tungsten bucking bars. They look great for tight spots and somewhere I read about a guy that only used that one bar for his entire RV10. My favorite bucking bar cost $5 used at Oshkosh, so I admit I'm frugal. I "flipped the canoe" this week so I figure I'm getting close to done with my riveting and $150 offends my Scottish heritage, especially considering 5,000 RVs have been completed without a tungsten bar.

However, I was pondering the matter and I wondered if there wasn't an even better cheap solution. In one of my other lives I reload and most of the bullets I buy are "jacketed." They're lead core with a copper jacket. Why couldn't someone come up with a lead core bucking bar with a steel jacket. I'd guess somewhere around 1/8 to 3/16" steel jacket would take the beating and the lead core could give the mass. It might take 2 different shapes - one for tight areas that may have the mass offset and one for the other 98% of the rivets. About the only drawback I can see is you'd have to put a warning label on the bars sold in California.

Anyone out there know how to form steel?

Me like!! Maybe you just run down to the metal yard and buy a small section of square tubing. Weld a plate on one end, fill with lead, weld up the other end, a little grinding and done. Seems too easy, there must be a reason this won't work.

Here is one reason which is not not related either price of the bucking bar or rivets itself but your healty. Propably not a big deal if you build one plane but in a long run this may become a issue.

Ergonomic field assessment of bucking bard during riveting tasks:

http://www.nexgenergo.com/ergocenter/trends/Wichita_308-0776.pdf

It is my understanding that tungsten is about twice as heavy by volume as lead and much more so than steel. So, while you might be able to spike a steel bar, you would still fall way short of a tungsten bar. The tungsten bar is about the price of one squeezer yoke; how many of those do you have? I doubt you would have any trouble selling the tungsten bar when you are finished building.

Health and weight

Tungsten weighs 19.25 grams per cubic centimeter while lead weighs 11.34 grams per cubic centimeter (both at room temperature, which is all I care about). So tungsten is about 60% heavier than lead by volume - a fact that I didn't know until moments ago. I'm not sure how practical the difference is if one had a carefully designed (shaped) bar. I'd imagine the business end could be appropriately small and the handle larger to make up for the missing mass.

As for repetitive use injuries, I'd want to see more data before I got excited about this. It's questionable to me if building one airplane over a period of 2 or 3 years (or more) is going to result in this sort of injury. If you rivet daily for several hours at a stretch, there's little doubt there's a risk but spreading out 15,000 +/- rivets over 700-1,000 days seems to reduce the risk a lot, or even eliminate it. Generally, I've only had a few days where riveting took an appreciable part of my time (riveting the wings and again the forward fuselage before flipping the canoe are the main exceptions). Even being a repeat offender doesn't seem to be much of a risk from what I can see. Of course, I only practice occupational therapy on the internet but my daughter who is trained in the profession has never raised the issue and she's raised plenty of other issues that I wish she'd left alone!

In any event, if I understand the article correctly, the greater the mass of the bucking bar, the lower the risk of injury. The lead-steel bar should be an improvement over a plain steel bar, which seems to have acceptable risks to me.

I never thought of looking for some steel channel to use but I think I'll see what I can find. My bullet casting equipment may have a new use. If I find anything that looks promising I'll post my progress and results here.

Penny wise and Pound foolish!

All this info about the alternatives, makes me want to purchase a
"new" tungsten bucking bar.
Maybe I'll just lend it to you Don......and you give it back when I start my -10.

I'm a giant cheapskate, but if I weren't nearly done I'd spend the $150. Having one tiny little super-heavy bar would be so cool.

R-10?

Bob Martin said:

All this info about the alternatives, makes me want to purchase a
"new" tungsten bucking bar.
Maybe I'll just lend it to you Don......and you give it back when I start my -10.

Click to expand...

By all means I'd be glad to borrow your bucking bar until you need it Bob. When do you plan on starting the 10? Might I suggest using my basement for your shop and then the bucking bar will be right there when you need it and it'll save all those long drives to Louisa.

tungsten bar

Don- I'll send you one for 100.00- use it for 1 month- if you don't love it- send it back- I'll refund your money! I promise- you'll LOVE it! I'll bet you'll think of selling your other bars on ebay to offset the cost. [email protected]