Small Diameter + Longer Thread Nozzle

After some previous failures at making smaller diameter nozzles, our new solution involved inserting a disc with a small diameter hole between the bottle and the gasket inside the bottle cap.

Unfortunately we were having trouble with leaks when we had a 1.5mm – 2mm disc inserted in the cap. The cap just didn’t have enough thread to make a good seal.

This week George from Air Command posted a video (definitely worth watching) showing how to use different types of bottle caps as nozzles to increase the length of the thread dramatically. This is just what we needed :)

We scoured the house for empty bottles / pump packs and found one that had the same thread as a drink bottle. We decided to commandeer it for testing … luckily the normal drink bottle top fitted the pump pack so no need to waste the contents of the pump pack :)

Pump Pack Nozzle and Normal bottle cap

Pump Pack Nozzle and Normal bottle cap

Its obvious how much longer the thread is on the pump pack .. The pump mechanism was disassembled. Use a pair of long nose pliers to remove the white disk from inside the cap, then bend some of the tabs on the pump section and it will come apart quite easily. It already has a hole ready for the gardena nozzle.

Pump Pack Dissasembled

Pump Pack Disassembled

Here is  a close up of the difference in size of the nozzle and the normal bottle cap

Normal Bottle Cap + Longer thread Bottle Cap

Normal Bottle Cap + Longer thread Bottle Cap

Top View Comparison

Top View Comparison

You can see on the last pic there was a small 1mm ridge that was filed off to make the top of the green cap smooth. This will allow a nice mating with the Gardena launch adapter. The existing hole was just about perfect, we probably enlarged it 0.5mm and the gardena snaped in perfectly.

Next step is to make the reduced diameter disc. Scouring the $2 shop we found some cheap signs that stick to the back of cars. They are 1mm thick plastic which is slightly flexible. A 24mm disc was drawn on one and cut out. A 6mm hole (can vary based on what size reduced nozzle you want to make) was drilled in the centre and cleaned up.

Cap + Gardena 9mm nozzle + gasket + 6mm disc

Cap + Gardena 9mm nozzle + gasket + 6mm disc

We found that the disc needed to be inserted between the bottle and the gasket (see below), other way around caused leaks.

Reduced diameter disc fitted

Reduced diameter disc fitted

Here it is fitted on the bottle

Nozzle Fitted to the Bottle

Nozzle Fitted to the Bottle

Fitted ready to test

Fitted ready to test

The longer thread nozzle clips properly into the launcher and doesnt pop out as George advised us to look out for which is good. See below

We tested up to 80psi with air only on a 1.5L bottle with no leaks. Next test will be with water to see how the disc stands up to the pressure of the water rushing out.

Tags: ,

This entry was posted on Thursday, September 3rd, 2009 at 11:22 pm and is filed under Development. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

 
 

Comments are closed.