Below are the materials and directions that we have settled on to make our ultrasoundable “LineBlock” ballistics gel central line/IV/arterial line trainers.

Materials we use:

Ballistics gel (one block makes 12 trainers)

Ballistics gel dye (optional, 2 cans per block of gel)

Baking pans (we bought 4 to be able to pour 4 trainers at a time)

⅛ inch outer OD tubing for artery tracks (one foot per baking pan)

¼ inch outer diameter (OD) silicone tubing for deep vein tracks (one foot per baking pan)

¾ inch OD latex tubing (2 feet per trainer)

Size 000 rubber stoppers (2 per trainer)

Size 2 rubber stoppers (2 per trainer)

18 gauge needles (4 per trainer)

Crock pot

Drill with bits

Expired central line kits

We buy expired Arrow central kits from esutures. You can search their expired stock. They usually cost $5-10 each.


Drill the baking pan(s) on each side where you want the tubing and/or channels. Use a drill bit that matches the outer diameter of the tubing or is slightly smaller.

We use 2 feet of the latex tubing for central lines so that a guidewire can be placed in either direction. For IV and arterial line placement, we use silicone tubing to create tracks. The silicone tubing doesn’t stay in the trainer. You’ll reuse the same stretch of silicone tubing to make each trainer. It’s heat resistant and easy to remove from the trainer after curing by stretching the tubing and then pulling it out.

Tear or cut up the amount of ballistics gel that you need into smaller pieces. We use ⅓ of the 16x6x6 inch block to make 4 trainers at a time.

Place the smaller pieces of gel in a crock pot. We recommend buying an inexpensive crock pot just for melting ballistics gel. You don’t want to use the one you cook in for this. There are other ways to melt the ballistics gel, but a crock pot is the best that we’ve found. If you accidentally overheat the ballistics gel (for example, in an oven), it will smoke. This hasn’t happened for us in the crock pot. We melt the ballistics gel on high in our crock pot for about 3 hours. Do this in a place with good ventilation. We do it either outside or in the garage with doors open. The ballistics gel makes fumes when it’s hot. Although it’s supposed to be non-toxic according to the manufacturer, we use gloves to handle it and avoid breathing in the fumes. After the ballistics gel is melted, you can add dye to it to make the trainer more opaque. You'll need 2 cans per large block of gel, so when melting 1/3 of the block for 4 trainers, we use 2/3 of a can.

Place the latex and/or silicone tubing in the baking pan(s), through the holes that you drilled on each side. Arrange the pans in a row and pour the ballistics gel in them.

Allow the gel to cool for about 3 hours. During this time, you can be melting the next batch of ballistics gel.

Remove the silicone tubing from the baking pans by stretching them and then pulling them out.

Remove the blocks from the baking pan(s).

Allow the blocks to cure overnight. Place plastic sheets between them if you stack them, otherwise they’ll stick together.

Place the size 2 stoppers in the latex tubing. Place the size 000 stoppers in the larger silicone track. We use capped 18 gauge needles (with the sharp tip cut off) in the small silicone artery tracks. The luer-lock end can be connected to an IV bag on an IV pole. With the IV pole elevated to maximum height, the pressure in the track will simulate arterial pressure. With the IV pole set at minimum height, it will simulate venous pressure. You can place an 18 gauge needle through the rubber stoppers of the latex tubing or the larger silicone track to pressurize them. Cut the sharp end of the needle off after pushing it through the stopper so it doesn't poke anyone.

After you use the trainers multiple times, you can heat up the surface with a heat gun to melt the tracks away. We have incidentally found that leaving the trainer in a hot car in the summer for a few hours also works!