Lab@Home Report: Flamethrower

Posted by HELiX

The full report’s done!

Link here: http://lab.helixated.com/flamethrower.html

And for lazy people, I’ll just copy the entire thing here… Lots of pics, so don’t mind the loading time.

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Overview

Flamethrowers are one of the most fascinating weapons ever created, probably due to the visual satisfaction it brings. Everybody loves a big flame, and that’s one of the main purposes of a flamethrower.

Basically, a combustible liquid is shot out at high velocities at a heat source (ie. candle) using the pneumatic airgun I made. The liquid will ignite and deflagrate in mid-air, travelling to its target and setting it on fire.

Disclaimer: This project is extremely, extremely dangerous. Do not try it at home, or anywhere else.

Construction

The design is fairly simple.

I pressurised the airgun to a mere 10 PSI (or possibly less), and stuff a ball of wet tissue down the barrel. This wet tissue protects the valve from the thinner and also, it pushes the thinner out, thus preventing any from flowing back.

The airgun will then be aimed at a lighted candle. The thinner, upon leaving the airgun, will ignite immediately when in contact with the flame of the candle. It continues it journey through the air while deflagrating until it reaches the target, which it will set fire to.

I had the experiment set up in the backyard. I got a cardboard soaked in water as the target placed about 2-3m away.

Testings

Shot 1:

About 30ml of thinner was used.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot1.avi
Right click, choose Save File As and watch it on your computer.

I also extracted the individual frames from the video for closer examination:

Shot 2:

Shot 2:

Slightly more thinner was used, about 40-50ml. Also, I placed a cardboard next to the chair with the candle to block out the wind from extinguishing the candle.

A larger flame was produced this time.

Also, if you listen in, you can hear my mom’s screams comments of “AIYOOO!”.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot2.avi
Right click, choose Save File As and watch it on your computer.

Individual frames extracted from video:

Failed Shot:

There’s also a failed shot which ended quite terribly. It’s actually the 2nd shot. Basically, 98% of the thinner shot out of the airgun missed the flame of the candle, and didn’t get ignited. It ended up splashing on the cardboard and all over the floor. The 2% that got ignited came flying behind, landing right into the pool of thinner, setting the backyard’s floor on fire. The fire spreaded really fast. Really got me very worried there.

As you would note, I have removed the audio from the video completely because… let’s just say, I wasn’t saying nice things at that point in time.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot3.avi
Right click, choose Save File As and watch it on your computer.

Individual frames extracted from video:

Aftermath

People learn from others’ mistakes, so should you.

Here’s a really stupid picture of me wrestling with fire…

…
…
…

But hey, I won in the end.

And also, fire extinguishers are important in households or you’ll end up doing something like this:

The floor was covered with soot at the end of the experiment. Really hard to clean off. Really.

Comments(0) 10:14 PM 1 January 2007

Lab@Home Update: Pneumatic Airgun

Posted by HELiX

Despite the success of the flamethrower, no, I’m not yet done with the airgun.

As you might have read, the airgun has an air leak at the 2″ End Cap above 60 PSI. After more than 3 days of gluing, applying epoxy and cement, I have finally capped up the air leak.

This is how awful it looks now:

It’s a copper patch that I applied all over the leaks. Really difficult to find the exact spots of the holes, so I had to redo and redo and redo…

My original aim was to pump the airgun to the maximum pressure the pump could handle - 100 PSI. So far, the copper patching manages to contain the air leak up till 80 PSI which is the highest pressure I attained with the air pump so far. It’s a foot pump rated at a 100 PSI limit, but after 80 PSI, I exerted all my weight onto the lever, but the piston wouldn’t go in further. As such, due to human physical limitation, I couldn’t pump above 80 PSI.

I’ll settle for 80 PSI I guess…

I’ll do the test shot at 80 PSI soon, but I can’t do it in my backyard as it’s really loud.

Also, I’ve worked on the projectiles.

I’m thinking of converting this into a projectile…

More details soon, but I’m pretty sure this will cause a hell lot of devastation!

Comments(0) 10:12 PM 1 January 2007

Lab@Home Update: FLAMETHROWER

Posted by HELiX

This experiment is extremely, extremely dangerous. Do NOT perform it UNDER adult supervision or you’re screwed.

—

YEAH. After painful week or two of waiting, the pneumatic gun is completed and it’s ultimate purpose has been recorded down on video.

Basically, using the pneumatic airgun I made a few days ago, I simply loaded it with thinner (the most accessible flammable liquid for me).

The design is fairly simple.

I pressurised the airgun to a mere 10 PSI (or possibly less), and stuff a ball of wet tissue down the barrel. This wet tissue protects the valve from the thinner and also, it pushes the thinner out, thus preventing any from flowing back.

The airgun will then be aimed at a lighted candle. The thinner, upon leaving the airgun, will ignite immediately when in contact with the flame of the candle. It continues it journey through the air while deflagrating until it reaches the target, which it will set fire to.

I did 3 shots before my Dad said enough and asked me to conclude the experiment.

I had the experiment set up in the backyard. I got a cardboard soaked in water as the target placed about 2-3m away.

Shot 1:

About 30ml of thinner was used.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot1.avi
Right click, choose Save File As and watch it on your computer.

I also extracted the individual frames from the video for closer examination:

Shot 2:

Slightly more thinner was used, about 40-50ml. Also, I placed a cardboard next to the chair with the candle to block out the wind from extinguishing the candle.

A larger flame was produced this time.

Also, if you listen in, you can hear my mom’s screams comments of “AIYOOO!”.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot2.avi
Right click, choose Save File As and watch it on your computer.

Individual frames extracted from video:

There’s also a failed shot which ended quite terribly. It’s actually the 2nd shot. Basically, 98% of the thinner shot out of the airgun missed the flame of the candle, and didn’t get ignited. It ended up splashing on the cardboard and all over the floor. The 2% that got ignited came flying behind, landing right into the pool of thinner, setting the backyard’s floor on fire. The fire spreaded really fast. Really got me very worried there.

As you would note, I have removed the audio from the video completely because… let’s just say, I wasn’t saying nice things at that point in time.

Or download here for smooth viewing: http://lab.helixated.com/flamethrower_img/shot3.avi
Right click, choose Save File As and watch it on your computer.

Individual frames extracted from video:

Here’s a really stupid picture of me wrestling with fire…

…
…
…
But hey, I won in the end.

The full report’s coming up! Stay tuned! =D

Comments(0) 12:07 AM 1 January 2007

193!

Posted by HELiX

After 4 years of being a geek…

I decided to wear contacts.

I decided to give sports a shot as a serious competitive interest. I’ve never been an athletic person, unless you consider cybersports, well, a sport.

But anyways, I decided to join bowling as my CCA in JC (on top of Astro which is a must). This might sound perfectly normal, but most people would just join club and societies along with performing arts at most. Also, I do not have any sports background.

Bowling, to me, was simply recreational and I liked it as a sport because of the aircon. Really.

Today was the trial for bowling. There was nearly 40 people who registered, and less than 15 would be selected. Kinda worried me, as I didn’t do any competitive bowling before and I wouldn’t know what kinda scores are good or bad.

We all had to pay $7 for 2 games and the rental of the shoes. Quite a few people had their own bowling shoes, which got me worried that they’re pro bowlers .____.

Ya, so, first round started off. There were 17 boys competing together, and the scores ended like this:

1st. Some guy - 154 pinfalls
2nd. Me - 152 pinfalls
3rd. Some guy - 150 pinfalls

Already, I was damn happy as it was one of my best on-form performances in bowling. The coach went around recording down the names of the better bowlers and I’m pretty sure mine was recorded as well.

Yup, so, the first round I had a good reason to believe that I got selected into the CCA already, but there was still a 2nd round, and it went awesome.

1st. Me - 193 pinfalls (MY RECORD. FAR, FAR, FAAAAR BETTER THAN ANY OF MY PREVIOUS ONES)
2nd. Some guy - 110+ or 130+. Can’t remember…
3rd. Some guy - In the 100s… you get the idea.

YEAH. ONE HUNDRED AND NINETY-THREE PINFALLS? CAN YOU BEAT THAT??

I started off pretty badly with a 9. And then, in the 2nd frame, I decided to play around with curl ball and I striked! From there, I decided to get back to serious bowling and it was no stopping from there.

The detailed score was something like:

9 X X / X X X 9 X 9

Yeeeessss. 6 unbelievable Strikes. 1 miserable Spare. And 3 Nines. I would’ve gotten a little over 200 if I did spare or strike the last frame, but I couldn’t concentrate.

Anyways, at the end of it, 7 of out the 17 boys got selected, basically all those who got above 100 pinfalls.

I tried to take a picture, but I couldn’t go up front and snap because it’d look really stupid and arrogant of me. So I got this at best:

If you stare hard enough, you can make out a few digits here and there. I’m the guy in the 2nd row, btw.

Yaaaay. ONE HUNDRED AND NINETY-THREE PINFALLS =D

Comments(0) 2:47 AM 1 January 2007

The Last Resort

Posted by HELiX

Ok, the glue didn’t work. I’ve result to doing this to cap up the leak:

Yessss. Cement.

Hopefully it’ll hold. If it fails, I gotta saw off the End Cap and redo everything…

ANd I’m gonna buy thinner or some flammable liquid tomorrow, and try out the flame cannon. Firing date should be tomorrow itself or over the weekend.

Comments(0) 10:45 PM 1 January 2007

Is it worth it?

Posted by HELiX

This might be a rant, but I seriously wonder…

Is my dedication to helping BP in the National Science Challenge this year worth it?

I’ve contacted the programme officer at Science Center. I’ve gotten him to send me the VCDs of the show for free. And today, one of the few days that I could return home early, I decided to spend the afternoon watching The Great Science Challenge 2004, recording down the questions and answers, while taking note of the format. I did that for four full hours and only covered four episodes. There’s still about 17 more to go. And also, I’ve decided to return to BP twice a week to train the team.

That’s the kind of effort I’d put in for any competitions. Difference is, I’m not the one joining this time.

Then I think… is it all worth it? I could be doing much better things with my free time.

Granted, I did it on a voluntary basis. I really wanted BP to win this time. Really. But what’s the point if the trainer/coach puts in more effort than the team itself?

Besides, I’m doing it for free. The past SQ trainers could probably cope with it because the team was much more interested in winning and they’re getting something out of it — being paid. No wait- they couldn’t cope with it. They had to blog about how screwed up the team was, although I would pick that team over the current one anytime.

Rong’en, Jim, Shaun, Dong Wei and even XJ now, all agreed to come back and train… so at the end of it, everyone might be wasting their time.

I’d like to apologise to whoever was around me when I got upset over the team. Whether was it because I became all weird, anti-social or too demanding. I won’t force or persuade y’all into the team anymore. It’s your decision now, whether or not you wanna join. And on top of that, you gotta make the distinction between joining to win or joining because you have/want to.

…

Yaaay, see? It might be moodswings or something, but I do write such blog entries too =X

Comments(0) 10:38 PM 1 January 2007

Airgun Leakage =(

Posted by HELiX

It’s horrible.

Sorry about the lack of updates on the airgun, because, beyond 60 PSI, the End Cap of the airgun produces a rather serious air leakage. I’m not settling for anything less than 90 PSI.

I reapplied glue previously around the small gaps, but I didn’t know where to concentrate on because the location of the air leak wass unknown. I pumped it up to 65 PSI today, and the air leak was so serious that I could feel the leak point.

Now, I reapplied the glue again, but chances are that it won’t work because the glue wouldn’t seep it too well. My Dad suggested cement, and although it might screw up the aesthetic factor of the airgun, I don’t have much choice.

Also, my neighbour came out today and saw me pumping the airgun. Yes, the same neighbour who came out when I did the test shot. She told me not to produce the same ‘boom’ (to quote her) sound again… which means that either I gotta make a silencer, or I gotta do further testings when she’s not around. I’m leaning towards the latter.

Hopefully, she isn’t in on friday and I can try the flame cannon =P

Comments(0) 3:21 PM 1 January 2007