Optional material for bulb construction???


Ok there is a huge push here and I am sure in other places for products that are friendly to Mother Nature. Alberta has banned the use of lead sinkers and wieghts for fishing. And after thinking about it for a bit the question can up.

Is there a optional material that could be used in making keel bulbs besides lead? One that would be friendly to the enviroment.

Has anyone tried other materials and to what success?



you could use other lighter metals, but they would be much harder to shape and cast.

if i rember correclty they banned lead sinkers and stuff because water foul where digesting them. something to do with the birds needing small stones to help break up food.

Lead is only hazardous if it is inhaled, (in a solid form, or vapor) or absorbed through the skin. The body has a hard time breaking it down and it stays inside for a long time.

Working with lead can be safe if the proper precautions are taken. Wear gloves and wash well after working with any hazardous material.
When melting lead, wear a respirator or at the very least do it outside and stand upwind.

Dan is correct about the birds eating the fishing sinkers. That is why it was banned.

Other options are:
Uranium. Heavier than lead, and only slightly radioactive. (Good luck getting any)
Steel. Not sure how you are going to cast or work with it.
Tin. Much like lead, but not as dense.
Antimony. Hmmm…that should kill you in short order.

Lead is starting to look like the best bet after all. Once the keel bulb is formed and painted, the only real environmental or health hazard is dropping it on you foot.

Peter R.

Visit www.climatemodels.com


To prevent harming mother nature/ the environment you can stop using lead, but you can also start protecting the environment against your lead.
First you can melt your lead in a closed environment with good air cleaning abilities. But to protect the fish against it, you can seal your bulb with epoxy.
I found on www.myrc.org in the library subject: “Beautiful Bulbs by D. W. Hoffman”

After you have smoothed the bulb with your file, and wet sanded it with #180 wet/dry, go ahead and attach it to the fin. After the epoxy or whatever you use to attach it cures, clean the bulb thoroughly with acetone. Now, before touching it with your dirty fingers, clamp the fin in a vise so the ‘pointy’ end of the bulb is down. Mix up some finishing (SANDABLE) epoxy, and apply it liberally to the bulb. Get your hot air gun (or wife’s hair dryer) and heat the bulb 'til the epoxy gets real runny. It will flow evenly and the excess will drip off the end of the bulb (don’t forget to put something beneath the point to catch the runoff).

After the finishing epoxy cures, there will be a little drop on the point - just sand it to the desired sharpness and watch out - needle sharp bulbs HURT.

You now have a finish that is incredibly smooth, and will stand up to lots of abuse. If you want to paint it, sand with #400 wet/dry, clean the sanding residue off with acetone (I like this stuff!!), then paint as you see fit.

Good luck Folkert

Jeff -

At least here in the States, lead shot has been replaced by steel shot for waterfowl hunting. Visit a “good” local gun/sporting goods store (not WalMart etc.) and buy the shot in bulk - 10 lbs is minimum at my shop.

Get a paper cup and accurate set of small scales and fill cup with steel shot to desired weight. I had to make my bulb mold slighty larger, but not by much, since we are talking grams and ounces here. Then use polyester or epoxy resin and begin mixing steel shot into the resin until all is mixed well.

The steel shot has some other metal in it to remain soft so it can be worked and shaped after. Just not as easy as lead.

If you want soft metal like lead - visit your local tire store and ask for free removed lead wheel weights ! As note, once encapsulated, it is “Earth Friendly” and I sure would like to see the bird that can eat/swallow a 4 lb. chunk of lead ! [:D]

Copper is not a bad substitute for lead. It is easy to melt and the density is only modestly lower than lead.

The Density of Lead is 9.4 Mg/cubic meter. Copper is 8.9 Mg/cubic meter or 95% the density of lead.

Steel alloys (BTW) are 7.4 - 7.9 Mg/m^3 and are very hard to melt, so they are not a great option.

The only other high density material that comes close to Lead is Nickle (same density as copper) but Nickle is also very hard to melt and is much more expensive than copper.

  • Will

Will Gorgen

Why not just use Iridium, the density of Iridium is 22.16 g/cc which is heaps heavier than Lead, which has a density of 11.37g/cc, i dont think its bad for the environment cause its an element that is either the most dense or the 2nd most dense material known to man.
Iridium is not attacked by any of the acids nor by aqua regia, but is attacked by molten salts, such as NaCl and NaCN. It is the most corrosion-resistant metal known to man.
the only problem might be the cost & that its hard to work with.
I got this information off http://www.scescape.net/~woods/elements/iridium.html
Regards Rob

Edit: Put where i got the information in

Something Is Nothing and Nothing Is Something!


<blockquote id=“quote”><font size=“1” face=“Verdana, Arial, Helvetica” id=“quote”>quote:<hr height=“1” noshade id=“quote”>ANYBODY TRIED TUNGSTEN?<hr height=“1” noshade id=“quote”></blockquote id=“quote”></font id=“quote”>
At almost a 4000 degree melting point, I think it may be hard for the average modeler to work with. :slight_smile:
Get out those propane torches!

Peter R.

Visit www.climatemodels.com


Ok great work one and all. Some intersting alternatives to useing lead. Everything from copper to tungsten was suggested.
I should have added that I did not think a fish or fowl would swallow a lead bulb. Mind you some of the Muskies caught on Lake of the Woods (Kenora Ontario) could have.

And I agree if the lead is coated after it “may not” be a hazard. And from the days of shooting Black powder firearms and pouring lead balls One must be very careful of the fumes.

So at least now we do have a few alternative items a person could use.



tungsten can also be worked and shaped with a lathe machine.if you can get a blank or a spent sabot round, you can turn it on a lathe machine and form a bulb

Why not use gold… :slight_smile: it’s quite heavy and it won’t oxidate so it’ll stay shiny forever.

…However, i think lead is the best option. Just seal it from the environment with paint or with epoxy as mentioned above. (i used epoxy and it looks perfect)

A tungsten welding rod placed inside a lead bulb would make the bulb much smaller for the same weight. Spent uranium (the stuff they use to make tank projecticles) is actually available and heavier than lead. Very dangerous is a bulb with liquid mercury inside, weight goes to the low side when the boat heels, but if you let the mercury out into the water very bad things happen. All of these are illegal under current racing rules.

What about using pewter (aka white metal, lead free solder and silver solder) You can use the same equiptment to cast the pewter but since the pewter will oxidize, you’ll need to seal it. You’ll also need a sightly bigger bulb.

Dump the keel, Sail multihulls! he he…sorry

Luff 'em & leave 'em.

point two cents worth- Lead shot already encased in resin is already sealed off from the environment. Like with a Soling which has a plastic skin