All Rocketry Blogs

Model Rocket Building: MX-774 Kitbash Part 1 Parts (2010-07-24)

At present, Michael's Craft Store is clearing out the Estes kits and engines. I'd already built a Estes Bull Pup 12D, but it was a little tough to pass up the clearance price. The plans for a sport ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 2 Engine Mount (2010-07-25)

This is the finished engine mount built as directed in the Estes instructions from Step 1. Mr. Wilfong's Kitbash instruction drawing shows the BT -20 engine mount tube as 4 3/4" long, but he doesn't ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 3 Fin Fitting (2010-07-26)

I know - enough with the Micro Maxx rockets - let's build something with a little more power! I decided to go with 3/32" thick fins. 1/16" balsa seemed a little thin. This is a sport scale model so ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 4 Fin Profiling (2010-07-27)

Here's technique loosely borrowed from guitar repairmen when they level frets on a fingerboard. They'll mark over the tops of all the frets with a Sharpie pen before leveling them flat. When sanding ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 5 Engine Mount Install (2010-07-27)

After a couple of dry fits I found the upper centering ring would be about 2 1/4" from the rear of the main body tube. To insure the ring would have glue around it, a dowel was marked at 2", 1/4" ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 6 Seam Filling (2010-07-28)

Some builder is going to read this and say: "He's doing what?" I've gone back and forth over the years on the best way to fill body tube seams. Thirty years ago I used white wall spackle, back when ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 7 Fin Trailing Edges (2010-07-28)

The MX-774 has four flat bottomed fins that stand flat and square. Sometimes you won't know if the trailing fin sides are square until the model is finished. You stand your finished rocket on a ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 8 Sanding Tube Seams (2010-07-30)

Here I'm sanding down the filler already dried in the body tube seams. Sand down the length of the tube, up and down, against the seam direction. Don't sand in a circle or along with the seam, you ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 9 Rounding Fins (2010-07-30)

I don't know if the Centuri MX-774 kit used 1/16" balsa, I would assume it did. Mr. Wilfong's kitbash instructions suggested using 1/16" balsa. I decided to go with 3/32" thick stock. The trailing ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 9 Filling Fins (2010-07-31)

I brushed Carpenter's Wood Filler onto the fins earlier today. My filler is starting to dry out a bit and get thick. You'll learn the proper consistency after a few tries. After applying, most of ... [Read More]

Model Rocket Building: MX-774 Kitbash Post 10 Tying Shock Cord (2010-08-01)

Many already know this technique, but for some who may not know it: Since Kevlar was used in rocket building, zippers have occurred. If the rocket is traveling too fast at ejection (too short or too ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 11 Fin Patterns, Tunnels and Servo Pods (2010-08-01)

To answer some detail questions, I used a combination of Mr. Wilfong's Kitbash and the old Centuri instructions. In upscaling this model, I had to multiply everything by a factor of 1.456 to get the ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 12 Servo Pods (2010-08-02)

All the Servo Pods had to have "wedge cut" ends. I found it easier to make the wedge on the open side first. Look closely at the picture, you can see the side opposite the blade already had the ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 13 Fin Position Marking (2010-08-02)

I cut the fin postitioning guide from the Estes Bull Pup kit instructions. Look how poorly it fit. There is almost a 1/16" gap where the guide ends should match up. I decided to make my own guide. I ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 14 Fins On (2010-08-03)

Here's the fins, in place viewed from the rear. I used the fin alignment guide I made in an earlier post. And the view from the side: Here's the side tunnels. One goes on each side, at the top ... [Read More]

Model Rocket Building: MX-774 Kitbash White Spray On Part 15 (2010-08-04)

After gray primer and sanding, I applied the white spray. Overall, the finish is coming along well. I'll have to do a little sanding to take off a few raised spatters before masking for the black ... [Read More]

Model Rocket Building: MX-774 Kitbash Masking Part 16 (2010-08-08)

This is a tough mask. Roll patterns are never easy, this one had it's own challenges. I wanted to be sure the horizontal mask lines were at 90 degrees to the line of the body tube. I cut some ... [Read More]

Model Rocket Building: MX-774 Kitbash Painting Part 17 (2010-08-08)

Here's that mask, almost ready for paint. I still have to add some cut up grocery bag pieces between the fins, but wanted to show it before all is covered up. Scotch tape wouldn't stay down and roll ... [Read More]

Model Rocket Building: MX-774 Kitbash Tape Trim Part 18 (2010-08-09)

I didn't feel like masking the ring on the upper body tube so I did a 1/4" wide wrap of black electrical tape. Electrical tape is an easy trim material for bands and stripes. When applying it, try ... [Read More]

Model Rocket Building: MX-774 Kitbash Part 19 Finished! (2010-08-09)

Did you ever have one of those builds you just want to put a fork in? I probably could have spent more time getting the masks cleaner or actually painting on the black band and small squares on the ... [Read More]

Model Rocket Building: MX-774 Kitbash Fix! Post 20 (2010-08-09)

After reading Mr. Wilfong's Kitbash instructions, I realized I made a mistake! Nothing major, I cut the upper band to 1/4" width. It should have been 3/8" wide. Here's how I cut tape strips. I lay ... [Read More]

Model Rocket Building: Model Profile - MX-774 Kitbash (2013-01-27)

  Semroc has just released a new MX-774 kit. If you have a Estes Bullpup kit sitting around - The plans for a sport scale MX-774 by A. Roger Wilfong are at: www.spacemodeling.org/JimZ/ ... [Read More]