MarkII
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I don't just clone FSI models.
From time to time in the past few years I have also built the occasional clone of an Estes Mini Brute. In 1971 Estes Industries began to sell the 13mm diameter, 1.75" long mini T motors. They replaced the Series III "shorty" motors. When standard-length 18mm paper cases were used, black powder rocket motors at the lower impulse levels were only partially filled, and some were as much as half empty. This unused casing was dead, inert mass that low-thrust A motors and fractional A motors had to lift along with the rocket. The shorty Series III engines were the first attempt by Estes to reduce this excess mass. To cut down on weight, they literally cut down the engine; Series III engines were rammed by Mabel into standard casings (presumably because that was what the motor-making machine was designed to handle), and then the casing was shortened by 1". This did help, but rockets designed for Series III engines still had to use, at minimum, a BT-20 body tube. Eventually, though, Estes was able to take advantage of much stronger paper casings to create engines at the low end of the impulse scale that had much thinner walls and much less inert mass. These were the "T" series of "mini motors" that are still very popular today. One of the consequences was that that the company could design rockets using the much smaller BT-5 tube. This created many new design opportunities. The company dubbed their new line of small rockets "Mini Brutes."
When the first few kits were designed, Estes was still using the "K series" to catalog their kits. They designated the first few with numbers starting with "TK-". Some, such as the Beta, the original mini Star Blazer, Midget and Birdie, were simply small K-series kits that were redesigned to use the new motors. When the company transitioned to using a four-digit all-numerical kit numbering system, the Mini Brutes were all assigned numbers in the 08xx series. Even today, if you see any Estes kit bearing a number starting with "08--" you can be certain that it is designed to use mini T motors. Estes reuses the numbers of discontinued kits for new mini motor powered models in order to maintain this numbering pattern.
Here and in the next few posts are photos of some of my "Mini Brute Mania" builds. To begin with, a group shot of five of them. In the front row, a clone of the celebrated Mosquito (now back in production!) and a Screamer. These were two of the first three MB kits that Estes introduced in 1971. In the back row, from left to right are a Super Flea, Javelin, Mini Bertha and Hornet. The Mini Bertha was third kit introduced at the debut in 1971. The Super Flea and Javelin were packaged together in a combination kit. The Hornet has a couple of interesting features. First, at 10.5" long, it was one of the smallest payload rockets ever produced. In addition, it uses the BT-30 body tube, one of the last Estes kits to ever to use that size.
From time to time in the past few years I have also built the occasional clone of an Estes Mini Brute. In 1971 Estes Industries began to sell the 13mm diameter, 1.75" long mini T motors. They replaced the Series III "shorty" motors. When standard-length 18mm paper cases were used, black powder rocket motors at the lower impulse levels were only partially filled, and some were as much as half empty. This unused casing was dead, inert mass that low-thrust A motors and fractional A motors had to lift along with the rocket. The shorty Series III engines were the first attempt by Estes to reduce this excess mass. To cut down on weight, they literally cut down the engine; Series III engines were rammed by Mabel into standard casings (presumably because that was what the motor-making machine was designed to handle), and then the casing was shortened by 1". This did help, but rockets designed for Series III engines still had to use, at minimum, a BT-20 body tube. Eventually, though, Estes was able to take advantage of much stronger paper casings to create engines at the low end of the impulse scale that had much thinner walls and much less inert mass. These were the "T" series of "mini motors" that are still very popular today. One of the consequences was that that the company could design rockets using the much smaller BT-5 tube. This created many new design opportunities. The company dubbed their new line of small rockets "Mini Brutes."
When the first few kits were designed, Estes was still using the "K series" to catalog their kits. They designated the first few with numbers starting with "TK-". Some, such as the Beta, the original mini Star Blazer, Midget and Birdie, were simply small K-series kits that were redesigned to use the new motors. When the company transitioned to using a four-digit all-numerical kit numbering system, the Mini Brutes were all assigned numbers in the 08xx series. Even today, if you see any Estes kit bearing a number starting with "08--" you can be certain that it is designed to use mini T motors. Estes reuses the numbers of discontinued kits for new mini motor powered models in order to maintain this numbering pattern.
Here and in the next few posts are photos of some of my "Mini Brute Mania" builds. To begin with, a group shot of five of them. In the front row, a clone of the celebrated Mosquito (now back in production!) and a Screamer. These were two of the first three MB kits that Estes introduced in 1971. In the back row, from left to right are a Super Flea, Javelin, Mini Bertha and Hornet. The Mini Bertha was third kit introduced at the debut in 1971. The Super Flea and Javelin were packaged together in a combination kit. The Hornet has a couple of interesting features. First, at 10.5" long, it was one of the smallest payload rockets ever produced. In addition, it uses the BT-30 body tube, one of the last Estes kits to ever to use that size.
Redacting for the Gallery versions are OK.
