How to Make Your Own Floats for Spearfishing

While some floats don’t ride well behind a boat when you are racing after tuna, these close cell floats get it done. They cost about $50-$100 depending on the size you make (30#-90# positive). They will not compress at depth, pop or get holes, and will not submerge when being towed. The obvious downside is traveling with them, and they look ghetto AF. However, the smaller and medium size ones do fit in a Sportube. I started making these when I lost a big bluefin after it sounded with all my gear. Never again! So if I see a monster bluefin this year and manage to get a good shot on it, I won’t be worried about losing my gear. Not necessarily pretty to look at but they work increable. I shared the benefits of these floats with Jon from @castandspear below.

DIY Float Process Step By Step

Type 1: Recommended for larger fish: 2 Part Foam Poured Floats

Materials Needed (Depending on the size, making more than one float is possible with these items)

1. 1/2" PVC Pipe 4' long

2. Closed cell 2 part foam 6 or 8 pounds more density

3. PVC Pipe 4", 6", 8", or 9" diameter 2' or 4' long or use PVC pipe jacket instead for desired size.

4. 1/4" Samson Rope Amsteel-Blue

5. 1/4" x 1" Washers

6. Circular bucket (Beach bucket, funnel, etc.)

Type 2: Recommend for smaller/medium size fish: Deep Water Floats

Materials Needed

1. 1/2" PVC Pipe cut down to 2' or 4' long

2. 11" Deep Water Floats or 14" Deep Water Floats

3. 1/4" Samson Rope Amsteel-Blue

4. 1/4" x 1" Stainless Steel Washers

Explaining Why with Jon from Cast and Spear

Making the Mold For 2 Part Foam Floats

Step 1: PVC pipe (#3 from materials list) will be the base of your entire mold. If you are using a pipe jacket instead of the solid pvc pipe, use duct tape to seal the jacket at the desired diameter. I will put the tape on the outside of the jacket and maybe a couple of smaller pieces on the inside.

Step 2: Drill a 1/2" hole in the center of the bottom of the circular bucket (#6 from materials list) that will be the nose section of the mold. This hole is for the 1/2" PVC pipe to fit into so that the line can pass through the middle of the float.

Step 3: Connect the "nose" bucket or funnel (#6) to the PVC pipe (#3) using duct tape to seal where the two ends meet. This is important to have it completely sealed in order to prevent foam from leaking out of the mold while expanding.

Step 4: Place the 1/2 PVC pipe (#1) through the middle of both PVC pipe (#3) and end bucket (#6) connecting it into the 1/2" hole located in the center. Seal off the connection point where the 1/2 PVC pipe and the end bucket connect in order to prevent foam from leaking out of the nose or blocking the center hole.

Step 5: The mold now should be complete, looking like a huge crayon with a 1/2 PVC pipe in the middle.

NOTES: Be sure to secure the mold upright. Also, the 1/2" PVC pipe needs to be located directly in the center of the of the mold. You may have to secure it in place during the curing process.

Pouring the Foam for the Float

Step 1: Spray mold release or use any cooking oil to reduce the likelihood of the foam sticking to the mold.

Step 2: Be sure that the air temperature is around 80 degrees. The cooler the air, the less expansion will occur once the 2 part foam is mixed.

Step 3: Pour both parts of foam into a bucket. Mix throughly.

Step 4: Pour 2 part of foam into your mold be carefully not to pour any foam into the center hole of the middle PVC pipe (#1). Ensure the mold stays upright and tap regularly on the side to reduce air pockets during the curing process.

Step 5: Once the foam has cured completely, take off the nose bucket or funnel (#6) off first. Then push on the end of the foam, and the float should slide right out the front-end of the mold.

NOTE: If for some reason the foam sticks to the PVC mold, you may have to cut the float out of the mold.

Assembling the Float

Step 1: Sand down any unwanted bumps or rough spots off of your float.

Step 2: Tie a Surgeon's Loop knot at one end then tie an Overhand knot just before the Surgeon's Loop knot.

Step 3: Slide a washer (#5) on the 1/4" Samson rope (#4) until it rest firmly against the Overhand knot.

Step 4: Feed your 1/4" Samson rope(#4) through the 1/2" PVC pipe (#1) in the middle of the float.

Step 5: With the rope passing through the middle of the float, slide a washer (#5) until is rest firmly against the float/PVC pipe.

Step 6: Tie an Overhand knot as close as possible against the washer.

Step 7: Tie another Surgeon's Loop knot at the end so that the 1/4" Samson rope is locked into place.