Wednesday, September 29, 2010

Long Time No See

So I haven't updated this in a while.

But I got good stuff. I built myself a computer from used parts and new parts that I bought in Taiwan! :D

Gigabyte GA-G31M-G2L Mobo
2.0 GHz Pentium Duo
80 GB + 1 TB HDD's
DVD-RW Burner

Back in US, I stuck it in a cardboard box and hooked everything together to make sure it all worked.

The initial setup of the computer when I came back from Taiwan:
Chyeaa. Ghetto.

For the record, we own a Macbook Pro and an upgrade disk so yea. Closer view of the cardboard box setup I had running. Airflow went straight up.

Even closer view of the box computer.

So then I stuck it in an old case and then I hooked it up to the sound system we have in our house with an RCA cable I cut and soldered to a 1/8-inch jack cable. I also hooked up the TV to it. My dad and I also built a nice "floating" desk to go with the new computer and monitor/TV combination.

Full view of computer with TV with sound system. Little center speakers on the floor under the TV. :D

Desktop view. With card reader jutting out unaesthetically. :P I can get those Wiimotes to work as pointers for the computer too! DarwiinRemote.

Underneath the desk. This desk came from the top of an old cabinet that my dad and I ripped off. We bought the supports and non-OEM screws from Home Depot and spent like several hours trying to get everything right. Ended up we had to prop it up on wooden blocks, which you can see in the top left corner. Still kinda rickety but good enough for non-heavy use.

I also got a used chemical ice pack from a friend, so I decided to have a little fun and try to recrystallize the ammonium nitrate in the water in the ice pack. I first did it by pouring some in a metal cup and putting the cup under a halogen lamp for like an hour. It worked - stuff boiled off and I got nice crystals. But it took way too long and wasted too much energy. So I made alcohol stoves from Altoids tins. :D

The base for the alcohol stove also acts as a carry case! :D

Grille for holding whatever you're heating, and the altoids stove on the right.

Little holes drilled in the side of the base so that air can go in and burn the alcohol. It'll make sense by the next next picture.

So we open the altoids tin with two rolls of gauze inside for absorbing and wicking off alcohol to burn...

So this is the stove fully set up, with that metal cup on top. The holes in the base draw in air which mixes with the alcohol in the gauze-roll wicks. That is lit through the hole on the lid and the flames reach up and heat the cup. :D Simple and effective. The grille was made from a computer fan grille with 4 bolts and nuts. Pretty simple.

Crystallized ammonium nitrate. Too wet to be used for anything, mostly proof of concept. You can see a few drops of liquid on the sides there near the top.

And that was what I did over the summer.

Tuesday, March 23, 2010

Nerf Gun Converted into Airsoft Gun

Hey, since my last post I got the Nerf Recon CS-6 for a few months now. Upon rediscovering the fun of shooting airsoft guns, I wanted a more powerful one than the cheapo pistol I had from Taiwan, so I "modified" my nerf gun a bit.

Actually, my nerf gun wasn't modified. This conversion was more of an attachment than a modification. (I did, though, modify the nerf gun to shoot farther. Standard air restrictor removal and penny spring mod. Shoots 50 feet with streamline darts).

Here's how it works.

I took a nerf dart and cut off the head. Now it's a nerf tube.

I took a steel airsoft barrel from an airsoft tank that I took apart quite some time ago and
1. Attached a circuit hook-up wire across one end with masking tape
2. Put a small line of masking tape on the inside on the same end of the barrel, making a full circle. (you can see it a bit inside the barrel here)

I stuffed the steel barrel into the nerf tube and the modification is now complete.

The small wire on the barrel end serves to keep the BB in the barrel when aiming and loading (muzzle-loaded), so it doesn't fall out the end into the nerf gun itself.
The small lining of tape serves to hold the BB in the barrel when loaded, so it doesn't slide out when the gun points down.

By simply stuffing the above modified dart into the barrel of the nerf gun, the nerf gun was thus converted into an airsoft gun.

Using a simple setup with a stool, measuring tape, a laser pointer, and a shopping bag, I used kinematics to find that the crude approximate speed of the gun is around 277.788714 fps (feet per second). This is using 0.12g low-end BB's. If a 0.20g standard BB was used, the speed would have theoretically been (using conservation of energy) around 215.174213 fps. Which is pretty close to some mid-to-high-end spring-powered airsoft guns. Dang.

What I did was put the gun on the stool and made sure it was level by eye. I used the laser pointer to line up the gun with a paper shopping bag 10 ft away. By firing the gun and finding the height difference from launch to bag puncture, I could find

1. the time it took to get there.
2. using the time found, calculate the speed it had over 10 ft.

Which came out to the wonderful number you see above.

When I have more time, I'm going to make a better setup for better speed calculation - using bubble levels and a stiffer bag for better measurement.

Sunday, January 24, 2010

Hey, BSoD!

I returned to my PC partition and started playing around with various games. One download came up as a virus on the scanner so I deleted it. Unfortunately, something went wrong. Several more virus alerts came up as well as strange IE8 ads so I closed down the ads and deleted the viruses. So I thought, "Hm, I better turn off the new BCM94321MC Apple Airport Card I installed in my laptop for Wireless-N in the Mac Partition," and did so. About 3/4 of a second after I hit the wireless switch, the laptop freaked out and went BSoD on me. Rebooting had no effect.

Several options:
1. AntiVirus Boot CD scan -- in progress.
2. Uninstall custom BIOS needed for new wireless card and replace with authentic - maybe.

It may be that the new wireless card's driver is interfering with something -- dunno what. The two different BSoD errors I got on two separate reboots seem to be pointing to a driver problem. Oh well. I gotta remove the viruses first. So far, scanning for 2 hours came up with 7 alerts (some of which are kinda dubious).