Slim Jim

[gstours]

As time permits,  lead could be gold,  butt only after some finished 👀 looks as applied.
   These jigs are kinda expensive after catching the bottom a few times.   Now there is no worries.🐟
The mold is the key.   Thanks again Dave.

[Gfish]

Cool!
I've gone to old spark plugs in place of 2-3oz. weights and auto tire balancing lead weights. The tire weights seem to be all over on the roadsides.

[gstours]

Thanks mr G for the offer.   I'll take all you can send.  USPS flat rate box 📦,  I'll pay for the shipping.
   More jigs are planned.   Just saying.

[gstours]

When pouring lead into the mold,  firstly the wire eyes should be connected, and another assist heavier wire added or without antimony thin jigs could flex under the anticipation of hoisting " the big one "
   My lead is scavenged from where ever,  cleaner is better.    Butt the rocks don't care 🤷‍♂️.

[Bryan Young]

I would recommend cooling the lead as slow as possible not to temper it so the jig will bend instead of crack under heavy pressure.

[gstours]

Thanks for your reply,  as these are thin,  and in a silicone mold I try to get them out or at least crack the mold to release some heat to the mold fairly quickly,  although smaller mass means less heat retention I believe.
  Pouring lead is kinda fun,  and here's another variation to mr, jimmy.........he weighed in at 240 grams.

[jurelometer]

I would recommend cooling the lead as slow as possible not to temper it so the jig will bend instead of crack under heavy pressure.

Hey. Bryan,

If you have a reference for that, I would be interested in reading it.

I thought that pure lead does not respond to any kind of heat treatment or quenching.  It will always be soft. Remelts of old sinkers, trolling balls, or dive belt weights are most likely to be "pure" lead, as unalloyed  lead is cheaper. Remelts of old wheel weights will contain alloys of various proportions that harden the weight, as pure lead is too soft to hold the clamp tight to the rim for very long.

I got a bunch of good information (and some misinformation  ) from the bullet making crowd.  For casting bullets, using some antimony, and back in the day arsenic (eek!) was the key to controlling  hardness.   These alloys would take a few weeks to fully harden (age hardening), but get there faster if the bullets were cooled rapidly (via quenching). 

Too much antimony in the alloy will make the metal brittle, but since the lures are not being fired out of a high velocity rifle, breakage or cracking has never been a problem for me except when tearing off a sprue on a very thin jig after pouring.  The better comercially made flatfalls use a very hard lead alloy in order to keep the shape and not lose paint as readily.

I mix harder alloys for most of my jigs.  I think it makes a better product, but it is a bit trickier to get good looking pours (not that the fish care )

-J

[gstours]

Thanks again Brian n Dave for your thoughts 💭.   I must say that this is as diatary as I've poured so far.
   By adding a heavy wire (rod?) in the mold was firstly pouring test.  It seemed to stiffen it enough to try as is.   It's def bendable with the hands,  butt it's done now,  soon to be soaked.
  That's why the Jim name,  it's kinda a combination bottom fish, salmon, cod, slack tide shallow halibut jig for when this could be used.    Salmon colors could be more citrus,  mabee with scales?
   My lead is a mixture of what I can find,  not pure lead, lots of skimming necessary before the blue.
The inner wire could be stiffer,  that, is next year.     I gotta go.   

[Ron Jones]

If brittleness is a concern, lead can be tempered with results similar to steel, that is slightly less hardness than quenching but significantly more toughness. A very fortunate coincidence that has been discovered recently is that baking powder coat (400 ish degrees for at least 10 minutes) is about perfect for tempering.

There are literally hundreds of bullet powder coating videos on the YTube.
The Man

[jurelometer]

If brittleness is a concern, lead can be tempered with results similar to steel, that is slightly less hardness than quenching but significantly more toughness. A very fortunate coincidence that has been discovered recently is that baking powder coat (400 ish degrees for at least 10 minutes) is about perfect for tempering.

There are literally hundreds of bullet powder coating videos on the YTube.
The Man

Good point about toughness vs hardness.  Not a good idea to lump the two together.  For casting lures with lead alloy, I pretty much only need to track hardness though.  A very thin soft lure can tear, but once hardened  (via alloying) to hold the shape and be dent resistant, I have not had any issues with toughness.

Pretty sure those bullets are not pure lead.  Alloying with antimony allows the lead  to respond to heat treatment. And there has to be a significant amount of antimony.  Old wheel weights have antimony, but they skimp a quite bit.  And the antimony tends to separate and float up when pot temperatures get in the higher range, so the typical home caster using salvaged source often accidentally removes most of the antimony when fluxing and removing the dross.  I expect that the typical home fishing lure maker is not going to see much difference in hardness or toughness based on how the part was cooled or reheated.

Assuming that there is still enough antimony to respond to heat treatment,  the bullet heat treating  tables that I have seen use 400F which is compatible with many powder coating paints. But the times on the tables start at one hour, which is about 5x too long for coating and will fry the powder. Curious if only 10 to 12 minutes will do anything (isn't tempering a gradual process?), especially on a larger saltwater lure, as the internal temps are not going to get that high that fast.

The bullet casting guys are making small simple shapes that are easy to pour well, but they are more interested in hitting  a narrower range of hardness for a batch of bullets to be used with a specific gun/ load.

If you are making lures and using  commercially produced molds sold to consumers, you will most likely be working with a nice fat simple shape that will pour easily with pure lead or a variety of alloys from salvaged sources.  Hardness won't matter that much other than helping to paint stay on. Easy Peasy.

If you design your own lures and get into thinner or more complex shapes, the alloys become more important, and will affect mold design and the final product performance. Using the wrong percentages can make it difficult to get a successful pour, especially a really nice clean, smooth, fully filled shape that will impress your friends.  We need enough hardness to keep the lure from bending or getting dented, but we don't have to be as exact on hardness like the bullet guys.   The  alloying metals are also less dense than the lead, so the alloy can change lure performance if you go too far.

Gary's jigs are big enough that even though the shape is on the flatter side, the cross section is thick enough that  it is possible to use "pure" lead.  The rebar technique is a good idea.

I don't cast bullets, but I have been messing with lure/mold design and mixing up different alloys. Pretty interesting stuff...

-J