want to cast some lead fishing weights with wooden molds

[cwsmith]

Mistake made in my entry. The 'wood' was an actual fabrication of the part we would cast. That was placed in a empty casting box and surrounded by wet casting sand. After the sand was set or cured, the box was opened, the wood modle removed, and then it would go to the floor where the molten iron was poured. My apology for the misleading mistake.

[LCHIEN]

I got a tiny ladle made for bullets.

The sinker molds are 50-60 bucks and I'd have to buy two for the sizes I go through a lot.

I'm thinking about a mold extension to make two sizes with one mold set, convertible.

If the wooden ones work I will buy some aluminum bar stock and make some permanent ones. I am imagining the wood ones will char and wear out after some use.

The economics is poor, lead weights are getting expensive but this is probably an exercise to see it I can do it. So far a $20 pot and a $12 ladle.
But I recently spent $20 bucks for 50 lead weights on eBay.

[Black walnut]

Sinker molds are available. Plenty of different types of sinkers. With that tiny pot you would need a ladle to pour.

wood molds, LOL. THAT'S JUST NUTS!

[dbhost]

I've never done casting, but I recall my Dad did. If I remember right the molds were some kind of sand... I remember he had a lead bulldog he said he casted in high school metal shop class. Of course he went to high school in the 1950s... I know a couple of guys that melt and cast their own 50cal bullets for black powder using old car wheel weights... If I recall lead has a pretty low melting point.

[LCHIEN]

What general shape do you envision using on the next derby cars? Can you cast bumpers, or drivers, or other? Looks interesting.

I had a dumb thought - low temp plastic for 3D printing - for making lost plastic moulds.

Not for detail pieces but for cast in place lead weighting for more streamlining. Higher density. Now I drill cylindrical holes and put in spherical or disc or egg shaped weights.

lost plastic is that like lost wax molds? Making a mold from a mold? I'll have to look up how that works.

[leehljp]

What general shape do you envision using on the next derby cars? Can you cast bumpers, or drivers, or other? Looks interesting.

I had a dumb thought - low temp plastic for 3D printing - for making lost plastic moulds.

[cwsmith]

Interesting... I didn't know they made a soldering pot for hobbyist.

When I was 14 or 15 I used to help my Dad in his plumbing business. Back then we used to use sectional cast iron pipe for sewer lines. One end was flanged and you placed two pieces together, put a hemp-like rope packing inside the flanged section, tamped it in and then using another rope-like wrap which had a steel opening to pour molten lead into the flange to seal the two sections together. We alway used a tank-top burner and bowel to melt sticks of lead; then, using a stone ladel would pour molten lead into the pipe flange.

Later when I worked at Ingersoll-Rand's Painted Post facility we had a huge foundry division that produced most of our castings. At that time I met a couple of brother's, both engineers at that foundry. We were in Toastmasters at the time and I got to know one of them quite well. They'd been casting metal since they were kids, taught my their father who was in the foundry business in Pennsylvania and in the 'old country'. At the foundry we used treated wood models which we would then place in a box and compact the casting sand around to make the mold for the pour. I wish I knew more about the actual process, although I did spend some time there photographing some operations.

Also, in model railroading (a hobby I once had when my son was a little guy) there was an element of casting that some of the more advanced hobbyist used. As I recall it was labeled as 'lost-wax casting". IIRC, you made a model of the part you wanted out of wax, then forming a mold around it with sand or plaster. When you pour the molten metal into the mold, it melts the away the wax and you have your part.

Not sure how helpful this info might be to you, but I thought it worth mentioning, as it might give you a path to explore.

CWS

[LCHIEN]

I guess a 3D printed mold won't work too well with molten lead...

There are some people making lead casting molds of wood.

I have a solder pot, some surplus lead. and some wood.



Could be useful in the next Pine wood derby car.