Mass-Producing Lead Weights for Scout Use?

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Vitamin K
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Mass-Producing Lead Weights for Scout Use?

Post by Vitamin K »

Hello Derbytalkers,

So a new Scout year has begun, and it won't be too long before those little kits get passed around. I'm ruminating on workshop ideas for cubs and dads, and, right now, I'm thinking about ways to make the build process as Scout-centric as possible, without sacrificing build quality.

One issue at hand is adding ballast. Now, i think the simplest kid-centric way to add competitive ballast would be to use Tungsten cubes. That is, just let them hot-glue them into the car. Simple. Safe. And easy to change if there's a mistake. But tungsten's expensive, and a Scout is thrifty, right?

So I'm wondering if I can find a way to reliably and uniformly cast a large amount of lead cubes or cuboids that could then be glued into the car body by the scout. For dimensions, I'm thinking something like 3/8" x 3/8" x 3/8", or maybe 3/8" x 1/4" x 1/2". I might go so far as to paint or spray them with some kind of clear-coat to minimize lead contact with skin. Then I could provide a "bag of ballast" to anybody who wanted to use it to weight their car.

I've got a melting pot, and I can find lead to melt. The question would be how best to build a mold to pour into. I think wood would be an acceptable substrate, provided that I "pre-burned" the interior faces. However, I'm not so great on woodworking, and I need some help for how I'd make the appropriately sized depressions. My dad's got a router that I can borrow. Would I be able to build some kind of fence to accurately create a number of square-edged holes to pour into, or is this going to be an exceedingly difficult operation?

Another option might be to cut wooden bars and assemble them into a grid to hold the poured lead, but that opens up the possibility of having gaps in the wood to contend with.

Any thoughts, guys?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Darin McGrew »

If you make square molds, then the scouts will need to cut square holes. If you make round molds, then the scouts will need to drill round holes.

When we pour weight (recycled tire weights, which are mostly non-lead metal now), the hole needs to be undercut, otherwise the cooled weight falls out. So if you route straight-sided holes in a block, then the weight should fall out easily once it has cooled.

If you use the same bit to drill the molds as you use to drill the holes at the workshop, then the weight should fit into it easily.

If you make different size weights, then you can weight the car and the weight, selecting the weight that brings it up to 5oz, and glue the weight in only after you know that the weight is right.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Topspin.D »

I make weights 3 ways.
- One is exactly like Darin suggests. Drill holes in a 2x4 for the size of slug you want and fill the holes with molten lead... and bang out the slug after it cools off.
- Second method is to route a series of grooves usually 1/4"x1/4"X2" in a 2x4. This size slug works well for how I typically build which is to route or scroll saw 2 weight pockets (like when using tungsten cubes). These can also be glued into 3/8" drilled holes and epoxied in place for a car with a thicker body/
- Third method is to use damp sand (usually in a shoe box) to create a sand mold the shape I want and then pour the lead in that to shape it. I usually do two sizes of box shaped weights (sort of like the "Sweet Spot" tungsten weight a vendor used to sell).
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Vitamin K »

Topspin.D wrote:I make weights 3 ways.
- One is exactly like Darin suggests. Drill holes in a 2x4 for the size of slug you want and fill the holes with molten lead... and bang out the slug after it cools off.
- Second method is to route a series of grooves usually 1/4"x1/4"X2" in a 2x4. This size slug works well for how I typically build which is to route or scroll saw 2 weight pockets (like when using tungsten cubes). These can also be glued into 3/8" drilled holes and epoxied in place for a car with a thicker body/
- Third method is to use damp sand (usually in a shoe box) to create a sand mold the shape I want and then pour the lead in that to shape it. I usually do two sizes of box shaped weights (sort of like the "Sweet Spot" tungsten weight a vendor used to sell).
I tried the sand method, but I couldn't get the sand to hold the shape I wanted, effectively. Possibly needed wetter sand, but was warned about using to much water in the sand (steam explosions).

I think I'll try the routed groove method. It occurs to me that if I routed the groove to the depth and thickness I wanted, I could affix spacers in there to break up the slugs for the length I wanted before pouring.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by birddog »

I tell my scouts not to mess with lead. It is dangerous and not worth the risks associated with its contact.

Personally, I wouldn't touch the stuff if I didn't have to (I reload shotgun shells, so end up dealing with 25# bags of shot quite a bit). If I was forced to use lead for PWD, I wouldn't melt it. I'd open up some shotgun shells and pour the lead shot into whatever size hole I had for my car and glue the shot in place while using gloves and a mask to minimize contact.

Why take unnecessary risks to save a few dollars? Penny wise and pound foolish in my opinion.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by whodathunkit »

Vitamin K,
Did you forget about the stick on tire weights?
That could also be painted or clear coated before being passed out. ;)
http://www.derbytalk.com/viewtopic.php? ... hts#p77430
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Vitamin K »

birddog wrote:I tell my scouts not to mess with lead. It is dangerous and not worth the risks associated with its contact.
Well, the issue of lead safety has been chased around the bush a few times here, so I won't really go too far into it. I'd just point out that the real risk of lead exposure usually comes from ingesting it, usually in powdered form. Everything I've seen in regards to lead handling seems to suggest there's not a lot of risk handling it in solid form, especially if one washes their hands afterwards. Add to this the fact that I'd be handling all of the melting and shaping, and coating each ingot to further reduce risk.
birddog wrote:Personally, I wouldn't touch the stuff if I didn't have to (I reload shotgun shells, so end up dealing with 25# bags of shot quite a bit). If I was forced to use lead for PWD, I wouldn't melt it. I'd open up some shotgun shells and pour the lead shot into whatever size hole I had for my car and glue the shot in place while using gloves and a mask to minimize contact.
The problem with using shot is that spherical balls are actually quite inefficient in terms of space usage. I can't find the link I had in mind, but I want to say that the amount of air gaps between spheres is something like 30-40%. When you're losing that much effective density, you may as well just go with zinc, in my opinion.
birddog wrote:Why take unnecessary risks to save a few dollars? Penny wise and pound foolish in my opinion.
Well, if I drop 25 bucks a car on tungsten and we build four cars (even more if you count the kids' Awana cars), that's a hundred bucks there. So the cost savings isn't inconsequential.
whodathunkit wrote:Did you forget about the stick on tire weights?
That could also be painted or clear coated before being passed out. ;)
Those are zinc, so they wouldn't need to be coated. Not as dense a ballast, but definitely an option to consider. Might suggest those for parents who would prefer to avoid using lead.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by bracketracer »

If parents want to avoid lead, what about square steel rod?

As an example:
http://www.homedepot.com/p/Everbilt-1-4 ... /204273977

Cut into 1.5" lengths it would fit into the same space as 6 of the 1/4" tungsten cubes. A 1.5" piece of 1/4" square weighs about 15 grams so it's nearly half the weight of tungsten but it's much cheaper, lead free, and readily available.

A person could substitute 3/8" square for more weight or even round rod if they want to use drilled holes?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Vitamin K »

bracketracer wrote:If parents want to avoid lead, what about square steel rod?

As an example:
http://www.homedepot.com/p/Everbilt-1-4 ... /204273977

Cut into 1.5" lengths it would fit into the same space as 6 of the 1/4" tungsten cubes. A 1.5" piece of 1/4" square weighs about 15 grams so it's nearly half the weight of tungsten but it's much cheaper, lead free, and readily available.

A person could substitute 3/8" square for more weight or even round rod if they want to use drilled holes?
Not a bad idea. I'm assuming it would cut well with a blade like this?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by bracketracer »

You could just have your scout use a hacksaw and clean it up with a file?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by knotthed »

He didn't ask about the safety aspects of it, which I don't know anyone personally affected by it, paint chips or otherwise - so I will not comment on that.

Probably not worth building a mold for when you can buy it.

http://www.rotometals.com/product-p/lea ... 1pound.htm

If Tungsten was not an option, I would personally choose lead all day long over any other substitute.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Vitamin K »

knotthed wrote:He didn't ask about the safety aspects of it, which I don't know anyone personally affected by it, paint chips or otherwise - so I will not comment on that.

Probably not worth building a mold for when you can buy it.

http://www.rotometals.com/product-p/lea ... 1pound.htm

If Tungsten was not an option, I would personally choose lead all day long over any other substitute.
Nice idea there, though I wonder if I can find a local provider, since shipping on lead is a bear if you can't get USPS flat-rate.

How would you cut the lead bars? A hacksaw would cut them no problem, but that would generate lead dust, which is something I'm eager to avoid. Hammer and chisel could do it, but then you'd have irregular ends. Is there some way to shear them into small blocks with straight edges?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by whodathunkit »

Thought you might like this topic as well.
http://www.derbytalk.com/viewtopic.php? ... ods#p55091
What type of automobile can be spelled the same forwards & backwards?
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Re: Mass-Producing Lead Weights for Scout Use?

Post by birddog »

knotthed wrote:He didn't ask about the safety aspects of it, which I don't know anyone personally affected by it, paint chips or otherwise - so I will not comment on that.
The whole point of my post was that he should be concerned with the safety aspects of it. So much so, that the entire idea should be dropped in my view.

I know several folks personally affected by it. In the reloading world, melting your own lead and dropping shot is a great way to save money, but it comes at some risk with handling the lead. I personally know folks who do this and have discovered elevated lead levels in their blood. I also know they make special soap for washing of hands to mitigate exposure. My lead bill for a shooting year is probably over $1000 and I could probably save 50% by dropping my own shot, but I don't do it as $500/year savings isn't even worth the potential for health issues to me.

Given all the issues associated with health risks to lead exposure, why would you ever even consider risking SOMEBODY ELSES' child to this? As somebody who is supposed to be a PWD expert, you are opening yourself up to major liability in my view.

If you want to be competitive, use Tungsten. If you want to save money, use Zinc or steel or whatever else is known to be safe.
Vitamin K wrote:Well, if I drop 25 bucks a car on tungsten and we build four cars (even more if you count the kids' Awana cars), that's a hundred bucks there. So the cost savings isn't inconsequential.
As for the additional costs, you were doing this for OTHER SCOUTS who are only going to build 1 car. For a $18 investment, they can get 4 oz of tungsten that can be used year after year. Amortize that over 5 Scout years for 5 cars and you are talking about less than $4 per car, not $25 per car for the scout who wants to save money.

If you want to do this for your own kids, that is your call. I just don't think a PWD expert should be exposing kids outside their own family to lead.
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Re: Mass-Producing Lead Weights for Scout Use?

Post by Stan Pope »

A relatively easy and long lasting mold can be made from two 2' of 2"X1/4" structural steel angle iron.

1. Place together to form a T when viewed from an end;

2. Clamp together;

3. Near each end, drill 1/4" holes and bolt the T together;

4. At each corner of the top of the T, drill a 1/4" hole;

5. Drill 1-1/2" X 3/8" or 11/64" holes (or another size as you wish) from the top of the T along the seam between the two sections of angle, spaced on 1/2" centers (clamp the area being drilled, because the angle will flex and bind the drill bit otherwise);

6. Form legs for the mold using a 1/4" X 2-1/2" or 3" bolt and two nuts to attach a bolt to each corner of the T;

In use, fill the mold holes to various depths to produce weights ranging from 0.5 oz to 1.2 oz. Working alone I suspend one end of the mold from the ceiling so that it can be drifted under the melting pot pour hole. One hand guides the mold while the other hand controls the flow of the melt. To release the slugs, remove the two end bolts that hold the T together.
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