Alex.Schweig's blog View Details
Posted by Alex.Schweig | Apr 25, 2011 @ 06:03 PM | 10,175 Views
Juan Fernando and I went up north to search for slopes sites on Saturday, and had a great time. Both these sites are 2 hours away from the city of Lima. One was a huge sand dune about 100 meters high and very steep, but the wind direction was not too good. The next site is a low ridge with a very good DS zone and the locals say wind is at least 15mph every afternoon !

At the second site, the Trinity F3F wouldn't penetrate at all, due to lack of ballast and the 30mph lift.

F3F Site Search (5 min 23 sec)

Posted by Alex.Schweig | Mar 20, 2011 @ 01:40 PM | 10,359 Views
My new acro chevron wing.

I like to do lots of close in, high agility acro. This 48" wing excels at it. Does inside and outside maneuvers quite nicely, retains energy well...

It's a copy of a Combat Wings XR, but made of high-density EPS due to the complete lack of EPP in Peru. Still quite durable since the LE and mid-section are glassed.

I need to start shooting some video!
Posted by Alex.Schweig | Mar 11, 2011 @ 11:20 PM | 11,184 Views
Today I got a small box in the mail.

It was, of course, my new Iwata HP-C airbrush.

Upon opening the box I discovered a sleek black case with gold lettering on it. Nestled inside was a very nicely polished HP-C.

Also included was a factory test of the airbrush's performance. I was amazed at the precision and fineness of the lines.

I quickly inspected the airbrush. Every piece is perfectly machined. The only minor defect was that the 0.3mm needle was lightly hooked (bent) at the tip. I quickly rectified this by rolling the needle on a piece of plate glass. It's amazing how thin the needle is! The Badger 150's (only airbrush I've used up to now) needle seems like a pig beside the HP-C's slim steel one.

This seems to be a great airbrush. I can't wait to start using it!

Thanks to George Voss for selling me this amazing little machine.
Posted by Alex.Schweig | Apr 17, 2010 @ 09:32 PM | 12,653 Views
I made a couple of these for a friend (upon request) and he tried them out today. Very nice sound and incredibly stiff, yet much nicer to use than metal picks.

I'm also thinking these would make cool earrings.

Dremel sanding drum for size reference.

Posted by Alex.Schweig | Apr 16, 2010 @ 07:12 PM | 12,379 Views
These are some carbon fiber earrings I made for my girlfriend's birthday.

The plate is (3k) carbon fiber and the hooks are silver. I'm also making a small mold for earrings in a flat spiral shape (impossible to cut by hand out of CF plate) for my sister, who has a connection with the symbolism of spirals.

When taking these to a fashion handicrafts store (specializes in strange stuff - out of the ordinary - zippers as earrings, little cloth cubes, lots of pop culture stuff... etc) for the hooks to be attached, the owner loved the concept of carbon fiber accessories and immediately asked me for my e-mail. It seems I'll be making some more of these.

Posted by Alex.Schweig | Jan 21, 2010 @ 11:00 PM | 15,814 Views
Overview of VARTM and Objectives

The acronym VARTM stands for Vacuum Assisted Resin Transfer Molding, or, in short, resin infusion molding.

The theory behind resin infusion is that dry laminates can be placed in a mold, allowing unlimited setup time, then liquid resin is inserted in the laminate by means of vacuum pressure.

The primary benefit of infusion is, of course, the unlimited setup time of the dry materials inside the mold. As there is no hand lamination involved, infusion is also "cleaner" and more "shop friendly" than other techniques.

Lastly, but most importantly, the use of VARTM allows the composite engineer to specify the resin/fiber ratio in the laminate. A volume of resin can be calculated to perfectly match the reinforcements used, providing lighter, stronger parts with fiber/resin ratios as high as 70/30.

{In the field of advanced composites, lamination techniques can be ranked as follows:
-Hand Lamination (fiber/resin ratio usually 50/50 or worse)
-Hand Lamination, then Vacuum Bagging (fiber/resin ratio of 50/50 or 60/40)
-VARTM or Resin Infusion (fiber/resin ratio of 60/40 and up to 70/30)

Now that we have a very basic "theory" of VARTM well understood, let's continue to the design specifications for this exercise.

Purpose of the exercise: Learn basic infusion techniques through the molding of a flat laminate in a specially constructed mold. Compare the properties of the three laminates that will be...Continue Reading
Posted by Alex.Schweig | Nov 20, 2009 @ 08:28 PM | 13,234 Views
In this exercise, I will make a sheet of roughly 5" x 3.2" carbon fiber servo horn material.

To save on materials, and because I only have 12 inches of 3.5 inch wide carbon fiber woven cloth, the middle plies will be composed of 4oz fiberglass cloth.

The flat tool is a 6.5" long, 4" wide piece of plate glass. The corners have been rounded and the surface has been polished. It will be waxed a total of twelve times, buffing between coats. PVA will not be used.

The vacuum bag will not be sealed directly to the flat tool, to avoid using sealant tape. Instead, an envelope bag will be used. The bottom of the bag will be carefully lined with two layers of paper towels to prevent any epoxy from contacting the bag surface.

The bagging schedule is as follows
-Flat tool
-Carbon fiber (5" x 3.5")
-4oz glass (0-90-0 weave orientation)
-4oz glass (45 or bias)
-4oz glass (0-90-0)
-4oz glass (45 or bias)
-Carbon fiber (5" x 3.5")
-Peel ply

Now, on to the required materials list:
-Flat tool
-Laminating epoxy (EZ-LAM 60 will be used)
-Clean working surface, wax paper or PE plastic
-Small acid brush and small square squeegee
-Measuring/mixing cup (medicine dose cups work well)
-Carbon fiber woven cloth
-4oz fiberglass cloth
-Rotary cutter or appropriate scissors
-Carnauba wax
-Very clean rags for waxing and buffing
-Vacuum system (EZ-VAC) and assorted accesories
-Peel ply and breather felt
-Cheap white vinegar and isopropyl alcohol for cleaning

Here are most of the materials laid out.
Posted by Alex.Schweig | Oct 24, 2009 @ 09:12 AM | 29,821 Views
Part One - Introduction and Materials List

Polyester tooling gelcoat is a thick, colored gel-coat for mold making. It is strong, and very economical compared to epoxy gelcoat. It is also quite strong, and scratch-resistant (although not nearly as much as epoxy surface coat or real industrial polyester tooling).

Here is a small instructable on making your own polyester gelcoat. Here in Peru, Tekno, the largest chemical company in the country, makes some really good quality polyester resin, sold pure for $4 a kilo. It is not "prepared": the user must mix in cobalt to form half of the catalyst (it will not cure if MEKP is not added - cobalted resin will not cure alone). Additionally, the user can mix in styrene monomer to thin the resin for laminating, as it is quite viscous in its pure form. For a gelcoat, we prefer to leave the resin unthinned.

To start off, here is the materials list:
-Pure polyester resin (1kg)
-Cobalt concentrate
-Measuring cups
-Mixing rods
-Storage cup w/ lid
-Cheap pantyhose or paint strainer (both work well)
-Aerosil/Cab-O-Sil/fumed silica/colloidal silica thixotropic agent
-Colored ochre powder (100g ?)

Each material will de described in detail in the next post, with photos for reference.
Posted by Alex.Schweig | Oct 08, 2009 @ 01:42 PM | 16,063 Views
1) Get some cheap polyester resin, and make sure it has already got cobalt in it by pouring a bit on a piece of wood and mixing in a drop of MEKP catalyst.

If it cures, then it's got cobalt pre-mixed in it. If it doesn't, you need to either get cobalt and mix it in to the right proportion, or get pre-cobalted resin.

2) Get talcum powder. Not baby powder, get real talcum powder as a filler. This can be found in composite supply stores, and sold by the 1/2 or complete gallon.

Measure out 1/16 gallon of polyester resin. Mix it with talcum until you have a homogenous mix that has the consistency of Bondo.

Whenever you want to use it, just scoop some out with your putty knife, mix with a drop of MEKP per teaspoon of putty, mix well, and apply!

NOTE: Please test your putty before actually using it on anything significant. By testing, you can get accustomed to the working time, or find a putty/MEKP ratio that suits you better

Posted by Alex.Schweig | Aug 02, 2009 @ 09:24 AM | 12,690 Views
Here's a little technique for filling pinholes. I learned this while repairing my Feroz.

Step 1: Get 1/32 gallon contact primer. It's gray or white stuff that does not need hardener, you just thin it and spray it, brush it on or pour it. It dries very fast and is quite inexpensive. It's sold as COMBO primer here by Sherwin-Williams.

Step 2: Get talcum powder. Don't use baby talcum because it's got all sorts of nasty stuff in it. Get real powdered talcum.

This recipe makes 1/32 gallon of pinhole putty.

Put your primer in a 1/16 or similar jar. Put in a nice handful of talcum and mix with a stick or a 4-40 rod.

Mix well and remember to scrape the bottom and sides. When it's all nice and mixed, add another handful. Mix. Add another handful. Mix well.

The final consistency should be about that of peanut butter: it does not level out and spikes will stay up.

Now you have an extremely useful pinhole filler. Use the tip of a knife to grab a spot of filler and push it into the pinhole. Grab another spot of filler and scrape it over the pinhole. This stuff should dry in 5 to 10 minutes depending on how much talcum you added.

It can be then dry sanded with 220 grit. Once you sand it, the pinhole has dissappeared

Warning: this is not structural putty! It will crumble if you use if for anything other than filling pinholes. Use Bondo for fillets and structural stuff.
Posted by Alex.Schweig | Jul 30, 2009 @ 11:45 AM | 12,894 Views
Video filmed at Parque Ghandi: July 29, 2009.

This is a bit of crazy flying filmed in 10 mph wind...

The plane (Rivington Hawk) is way too heavy for the wind conditions!

The paraglider guys are on tandem sails and still they can barely fly....

Pilot is the owner of the plane. He used to be the national dirtbike champion. He flies his planes like dirtbikes
Aka- one pointers, crash landings, landing on people, crashing into the road 80 meters below, etc

Observe the end of the video very carefully!!!

Parque Ghandi: July 29, 2009 (1 min 18 sec)

Posted by Alex.Schweig | Jul 27, 2009 @ 11:11 PM | 13,038 Views
Today was a national holiday starting at 12:00, so I took a break from working on the JART and went to fly at Ghandi with some friends.

I didn't have any operational planes, but one of the guys there owes me a few favors (I pick up his planes when he crashes them into the slope, which is about every time he flies something )

He let me fly his battered little Rivington Hawk.

It's a fun little plane, but the C.G. was a bit off and it would tend to spiral when doing stall turns.

Next in line was the ASW-21. This is a very beautiful plane, but this guy treats his planes like , and the wings and tail were all banged up. As usual, the guy just slapped a battery pack into it and a bit of lead and thought the C.G. was good to go. It spiraled right after launch.

Down she went. I picked her up, the guy moved everything forward and secured it with tape.

On the second flight the lead ballast got loose and went back through the tail boom, hitting the balsa rudder and breaking it from the inside

The change in C.G. brought it down. Then it was my turn to fly it and I enjoyed it very much, although I would have changed the trim settings if I could.

The plane later mid-aired with a chinese "thermo-fox", resulting in a broken nose, bent steel wing joiner and a couple of chips in the gel coat.

These videos show some of my flying, but not nearly at my best, as these planes are not mine and are trimmed badly and not balanced at all.


PS- I'll try to get some decent video of the Samurai this weekend!

Parque Ghandi: July 27, 2009 (1) (0 min 40 sec)

Parque Ghandi: July 27, 2009 (2) (0 min 8 sec)

Parque Ghandi: July 27, 2009 (3) (1 min 23 sec)

Parque Ghandi: July 27, 2009 (4) (0 min 46 sec)

Parque Ghandi: July 27, 2009 (5) (1 min 8 sec)

Parque Ghandi: July 27, 2009 (6) (0 min 50 sec)

Posted by Alex.Schweig | Jul 27, 2009 @ 10:30 AM | 12,921 Views
Snoring is positive encouragement when building.

Here's my favorite snoring machine

Today I woke up to him snoring a few inches from my face

He's on top of my mom's favorite couch pillows. Photo taken 5 mins ago.

I give you: Hugo the Snug Pug
Posted by Alex.Schweig | Jul 19, 2009 @ 03:38 AM | 13,156 Views
A short collection of clips of me landing a friend's Spirit Elite in way too much wind!

As can be seen, I was doing closed turns and intentionally stalling while turning to bleed off speed.

The final landing was quite nice

30 mins later, the owner of the plane tries to land it himself and smashes it against a brick wall on the far side of the slope.


Spirit Elite Landing (0 min 50 sec)

Spirit Elite Landing Part 2 (0 min 12 sec)
...Continue Reading
Posted by Alex.Schweig | Jul 06, 2009 @ 12:48 PM | 12,835 Views
Posted by Alex.Schweig | Jun 27, 2009 @ 09:25 AM | 12,969 Views
Spanish A1: 98/100 (#) = 7/7 (MYP)

Humanities OPP (Peruvian Program): 100/100 (#) = 7/7 (MYP)

Science (Thermochemistry and Elements): 5/7 (MYP)

Math Extended 9E: 6/7 (MYP)

English A1 9: 5/7 (MYP)

Posted by Alex.Schweig | Jun 19, 2009 @ 04:54 PM | 12,795 Views
Exam Schedule is as follow. Will post grades at the end of the week.

-Tuesday June 23: Math 9 Extended (Numbers and Sequences, Real Numbers, Radicals, Exponent Laws, Line Segments, Quadratic Equations, Trigonometry, Statistics, Probability, Polynomials, Algebra, Quadratic Relationships, Relations and Functions... etc...) , Spanish A2 (Advanced)

-Wednesday June 24: Humanities OPP, Digital Media Production

-Thursday June 25: English A2, Science (Thermochemistry & Environmental Science)

Posted by Alex.Schweig | Jun 18, 2009 @ 05:01 PM | 13,026 Views
We're slopers.

We're the funniest, craziest, coolest crowd there is.

We're adrenaline junkies, speed freaks, scale maniacs, toy builders, composite freaks, and cliff dwellers.

We're rebellious, fun, entertaining, helpful, playful, talented and patient.

We like our toys long and pointy

We also like them nice and shiny.

We like to go fast. We love to do insane aerobatics mere feet from ourselves.

We like to feel the rush of the wind in our ears.

We are made for the wind. The wind is made for us.

and his summary of a sloper in hardly enough words.
Posted by Alex.Schweig | Jun 09, 2009 @ 09:12 PM | 12,669 Views
Exams are in 2 weeks!!!!

Don't expect much updates on the JART during this time

My birthday, June 24, is the day of my Math Extended and Physics exam
You can imagine how I feel about that