Introduction: Lead Hammer Mold for Machine Shop
I found a small (about 350g) lead hammer somewhere sometime.
Didn't use it much at first, found its way to my home shop where it's now used almost every time I set something up to machine. Homing parts in the mill vice or lathe chuck, anything I need to tap & not hurt, tight end-mill in ER collet perfect job for the lead hammer.
Anyways... good things never last, the handle broke inside the lead - bugga.
Time for a quick project...
This hammer is not intended for heavy blows, use is for tapping & mild whacking.
WARNING!This project implies using hot liquid metal, wear appropriate eye protection/face shield & appropriate Protective clothing. Lead is also hazardous, wash your hands after & don't chew on it.
Ingredients: This is what I used, customize with what you can find or size to your need.
1x Piece of gal steel tube 60mmL x 33.8mmOD ~2.5mm wall thickness - the mold.
1x Piece of 50 x 50 x 10 or 12mm aluminum flat - the base.
1x M4 x 20mm 304SS screw.
1x Hose clamp SS.
1x Length of zinc plated 6.35mm mild steel rod 120mm - the handle shaft.
1x Length of strong plastic/wood 30mm x 120mm length. - the handle grip.
Step 1: Make the Mold Body.
1. Cut the tube slightly longer & square/flat the ends.
2. Bore the inside for a smooth finish.
3. Slit the tube length-ways into 2 equal halves with a hacksaw, 1 cut on the weld seam.
Mark the 2 halves as they must go together how they were cut.
4. File smooth the cut edges, check fit for minimal gap,
5. Put the 2 halves together they will be out of round, place horizontal in vice & squeeze to improve roundness.
5. Linish the 2 long edges with abrasive paper on a flat surface, check fit together with minimal gap.
6. Fit hose clamp(s) around the 2 halves & tighten, check everything goes together nice, now place end on in vice fitted with soft jaws & 1 slit at top, re-check is still aligned.
7. Center punch on one slit (about 60/40 position for this handle), drill a small pilot first , then the same size as handle rod, or undersize & enlarge . The hole should hold the handle firm else it will drop out of square. (it could be supported externally) You can also use aluminum foil to pack the hole if its loose.
! --> Make handle shaft first & check hole position so internals are away from ends.
Step 2: Make the Handle Shaft.
Using the vice, bend 1 end of the rod at about 25mm back on itself then bend back half way along the "U".
1. First make an "L" with 25mm at 1 end, then place the long section in vice with short section pointing up, hammer the short bit down onto the long section then press together in vice with soft jaws.
2. Using just 1 soft jaw, (see image) put the double "U" section into vice half way & bend the handle down.
!!! This bend must be smooth radius with no nicks, else the handle may fatigue break prematurely.
3. Thread the end of handle.
Step 3: Make the Handle Grip.
1. Using a piece of 30mm strong wood or plastic 120mm long, bore a hole the same size of the handle shaft ~30mm deep.
2. Using a smaller bit drill the hole deeper appropriate for the threaded section.
3. Thread the smaller hole using the handle shaft end.
4. Shape the handle, place a collar ring on the hole end if wood.
Step 4: Make the Base.
The base is a flat plate with pocket hole sized for a 'just loose fit' of the mold body, with side screw clamp.
1. Cut aluminum plate into a 50mm square, set in 4 jaw chuck & drill a hole in center 5mm deep, increase the hole with larger bits then machine the hole just larger than the 2 piece mold & smooth flat the hole base. [Or CNC the pocket with end mill]
2. Drill & tap an M4 thread in the side for the screw to clamp the mold.
If u don't have a lathe, maybe hole saw thru the base & screw on a bottom.
Step 5: Final.
Put mold together as shown in 1 of the images with handle shaft in place . Fit hose clamp at top & tighten, check ends & edges are aligned, place in base & apply force then tighten lock screw. Mold must be fully down into base & clamp screw 90deg. from mold seam. Check handle is square & held tight (al-foil can be used to tighten handle in hole).
It's now ready for casting.
It is not critical to have no gaps as lead will solidify quickly in the cold mold, but my machinist hat won't let me do a half-assed job.
The handle shaft will loosen inside the lead over time, just squeeze in a vice to tighten.
The head will also mushroom over time, just hammer it back into shape.
This instruction does not include molten lead pour, that's another story research it...