Archive for July, 2010

 

Horizontal & Vertical Launcher Upgrade

Since we have been concentrating on water rocket cars for the last 6 months, our vertical water rockets have been collecting dust in the garage. So this weekend we have upgraded to launcher so it can be used for horizontal as well as vertical water rockets. This way we can launch the water rocket car as well as our vertical water rockets on the same launch day.

To achieve this we have  added an extra splash guard on two hinges which are fixed in the horizontal position by 2 bolts. We will replace the nuts with wingnuts to allow easier removal.

Extra Splash Guard on hinges

The extra splash guard has a slot cut out for the launch string to feed through in horizontal launch mode.

Splash Guard slot

Here is the launcher in the horizontal launch mode with its height adjustable gardena quick connect.

Launcher in Horizontal launch Mode

A support rod was cut and bored through the centre to allow a bolt to fit in it. A correct sized nut was then countersunk and apoxied into the top of the support rod.

Support Rod with nut embeded

The support rod clips onto the launcher when not in use

Support Rod stored while not in use

When the two botls are undone from the bottom of the launcher and the splash guard is moved to the vertical position, the support rod fits into a 22mm countersunk hole in the underside of the splash guard. A screw then holds it solidly in place. Here is the launcher in vertical launch mode.

Launcher in Vertical Launch Mode

The launch string is moved to  accommodate the vertical launch through a 90 degree bend.

Launch string moved for vertical launch

It takes only a couple of minutes to swap from one launch mode to the other. The 20Litre water container is used in both modes and keeps the launcher firmly in place.

Posted by on July 19th, 2010 Comments Off

High Pressure Air Hose – Upgrade (100th Post)

This weekend we have upgraded the air hose on our launcher to the new 290psi (working pressure) air hose.  The air hose had Nitto connectors so we have continued to use these where a connector is needed.

First step was to remove the old coiled air hose and install a Female Nitto quick release to the Air pump hose. The air pump hose has an internal diameter of 8mm, so getting the 10mm barbed section down the middle of the air hose took a little while. Here is the pump with its Nitto quick release installed.

Air Pump with Nitto Quick Release - Closeup

and another pic of the pump

Air Pump with Nitto Quick Release

The Nylex High Pressure Air hose is 15m long and the male end clicks straight into the quick release on the pump.

Pump and Air Hose connected

The next part was to install a male Nitto connector to the abort section of the launcher.

For this we used a small section of the Nylex hose and one of the male Nitto connectors. As the Nylex hose has an internal diameter of 10mm this was relatively easy. The other end of the Nylex hose connects to the abort T piece which has a 12mm barbed section. This took a bit longer to get on, but some hot water and a few expletives later and it was on.

Abort section with Male Nitto connector

The male Nitto connector on the abort section clicks into the female quick release of the 15m air hose.

15m Air hose and Abort section connected

The Gardena quick release is still used to connect to the launcher itself. We will probably upgrade this in the near future now we know the 10mm hose will fit over a 12mm barb. We will also be replacing the plastic release valve with a metal one and increasing the length of hose from the release valve to the launcher.

The Gardena uses standard 12mm fittings, whereas the air hose use a standard 10mm fittings, so there needs to be a conversion at some point. Here is a pic of the pump and abort section all connected.

New Airhose - all connected

A quick test today up to 100psi showed no leaks, we will do a higher pressure test prior to the next launch day.

Also a small milestone, its  our 100th posting on the HHWRSA website and our 2 year anniversary of HHWRSA :)

Posted by on July 18th, 2010 Comments Off

Water Rocket Car MkXI – Launch Day

Even though it was a cold and slightly rainy winters day here, we were very keen to try out the Green Hornet with its new configuration, so we had a lunch day on Sunday afternoon.

The new rear end fins and low traction wheels were designed to make the water rocket car act more like a rocket for stability rather than a car, ie: The rear fins straighten the back of the rocket car. This means the rear fins need to overcome the friction of the rear wheels to effectively straighten the rear of the car.

Sounds good in theory .. time to try it out.

New Rear End of Water Rocket Car

Here is the video of the launch day. We managed only 2 launches due to the rain. We also had a father and his son on motorbikes stop to watch our second launch, that’s the noise you can hear in the background.

Results
Well we had partial success in that the launches were pretty straight, especially the first one, until there was any r/c steering input, as soon as the front steered, the rear of the car had no grip to follow and just fishtailed or did a 180 degree turn.  Obvious really after thinking about it, just like doing a handbrake turn in a normal car, …. On both runs we hit the gutter, we haven’t done this for a long time, even the r/c steering couldn’t control the cars direction when fishtailing.

Positives from the tests were the rear fins look to be working but we will need to put rubber back on the rear wheels, so we will see if there is enough force generated by the fins to straighten the car under thrust with the old wheels on.

The launcher updates worked great. The lightened chassis did work well as the car definitely accelerated quicker than the last revision.

We will keep working on it :)

Posted by on July 13th, 2010 Comments Off

Website Back online

The HHWRSA website has been down the last 2 days, but we are back online again. This was caused by engineers at my ISP deciding what they thought was best for me and removing my static IP address and giving me a dynamic one.

Seven (7) calls in eleven (11) hours to the ISP’s customer service failed to convince them that I was indeed entitled to a static address, ended with me no closer to getting back online and a customer service manager not willing to help any further until Monday.

An email at midnight Saturday night to the ISP’s CEO and Managing Director and I had a call Sunday morning when I awoke with my static address restored and apologies for the inconvenience.

Credit where credit is due though to the management of the ISP, they certainly fixed my problem quick smart once it was escalated to them and provided follow up to make sure I was all back online, on a Sunday !

However it shouldnt have needed to get that far in the first place if the customer service reps, engineers, customer service supervisors and customer service managers did what they were supposed to do, listen to their customers and provide good customer service.

Posted by on July 12th, 2010 Comments Off