Saturday, July 23, 2016
The launch lugs are short, shorter than I remember.
After they were lightly tacked down and the glue dried, a rod was used to make sure they were in line.
TIP: When gluing lugs and fins try using very little glue initially.
It doesn't take much glue to tack them on. If they dry and end up out of line, it's easier to remove the parts and try again.
The fins and body tube will be shot separately with primer/filler.
A strip of masking tape the length of the root edge was set down the fin position pencil lines.
After the primer/filler dried you can see some raised pore lines.
The was also some open pores. The open grain got a rub of CWF and smooth sanding.
The primer/filler helps to fill whats left of the nose cone molding seam. You won't see this until the primer/filler is sanded down.
Friday, July 22, 2016
Sure I should be excited, but maybe not.
Over 2,700 hits from Russia?
Typically the blog gets anywhere from 750 hits to 1,500 a day. It varies, weekends get more readers.
These have got to be some sort of robotic hits but I'm not seeing any questionable sources like "Vampirestats".
I've cracked the country of Moldova this month! Great, now I have homework. What's a Moldova?
EDIT: I just did a search. The first listing that came up was for Anatasia Date, a Moldovian Marriage site. Hooray! Rockets are finally a chick magnet with single Moldovian women!
The second listing: "Moldova, officially the Republic of Moldova, is a landlocked country in Eastern Europe, bordered by Romania to the west and Ukraine to the north, east, and south. The capital city is Chișinău."
See what you learn on a nerdy rocket blog?
One of the nose cones had "scars" on it.
It looks like some plastic flash was cut off at the factory.
It looked worse than it was and sanded smooth with 220 grit sandpaper. 400 Grit was used before any spray primer.
This was one of the first kits to use this style of card stock fin marking guide.
I did have trouble getting it over the BT-60 tubing. The center hole was slightly enlarged with some 220 grit.
TIP: The engine mount was glued in first before marking the fin lines. Sometimes it's easier to glue in the mount first. You avoid any trouble lining up the engine hook under the launch lugs as the glue is quickly setting up.
So the engine mount goes in first, then mark the tube for the launch lugs and fins.
Two guides are used. Set both the "flats" on a table and mark with pencil in the V notches. Line the launch lug line directly over the engine hook.
Extend the notches down the tube with an aluminum angle.
Thursday, July 21, 2016
Here's a great blog from Zurich, Switzerland -
VINTAGE ROCKETRY RETROSPECTION
"Incoherent reminiscences and images of building and flying A to N motor powered model rockets in Switzerland and elsewhere since 1975."
Lots of pictures and history. To check it out, CLICK HERE
I would think - the harder the wood, the harder it is for the laser to cut through it. The top cut was burnt and wide. The cut didn't go all the way through to the bottom.
I took some passes with a sharp knife to get through it.
I don't mind hard balsa fins, They'll hold up better on a hard landing.
With laser cutting there is no real need to gang sand fins to get them all the same shape.
Hand cut fins should be stacked and gang sanded to get them a consistent shape. With laser cutting, you draw one then copy and paste it two or three more times. It's the same fins profile over and over.
When sanding off the burnt edges at a 90 degree angle you can see the wedge angle of the laser cut.
I've read instructions where you are told you can leave the burnt edges as is. They say glue will still hold on the charred edge.
Not me. I remove it and square up fin edges with 220 grit on a sanding block.
Wednesday, July 20, 2016
I prefer doing 1 1/2 wraps of tape with two wraps over the engine hook.
Start the wrap halfway between the Q-tip tube and the engine hook.
The tube and engine hook are directly opposite each other.
Continue all the way around, over the Q-tip tube then back over the starting point.
Continue around over the hook a second time.
Mark the tape on the opposite side you started from. Lift the tape wrap and cut off the tape. Press the tape down - done!
The engine block is recessed about 3/4" inside the top of the engine mount tube. Sometimes a loose block can get glued in crooked when it hits the top bend of the engine hook.
TIP: Apply glue inside the tube and press the block in place with an engine casing. The casing will keep it straight all the way onto the engine hook bend.
Tuesday, July 19, 2016
After applying some CA glue to the inside top and bottom of the engine mount tube, the tube edges got some CA, too.
The edges will be squared off with some 400 grit on a sanding block.
Before applying CA to the inside tube, look ahead in the instructions. Be sure that nothing will be glued over the area that got sealed with the CA glue.
(The top two rings should be flipped, the one on the right should be on the left. It's the lower ring.)
Pencil lines were drawn through the centers.
The right sides get a punch for the Q-tip tube that'll be part of the replaceable Kevlar line.
The ring on the right got a small "divot" punch to go over the upper end of the engine hook..
The upper ring is set farther down and over the top end of the engine hook, again for more strength.
The red tube is a hollow plastic Q-tip tube. With the rings dry fitted I can cut the tube to size. It'll end up just a little longer than the space between the centering rings. The ends of the tube will stick out the holes on either side, about 1/16"
TIP: If you have a ruler that has the measurements starting even with the end, use it to check the ring depth three or four places rotating it around the tube. This will get the ring placement 90 degrees to the tube.