Model Rocket Building Blog 
Model Rocket Building Posts
Rocketry Product: Estes - Astron Sprint XL {Kit} (007224) [2013-]
Estes Sprint XL Background (2017-02-01)
The first K-49, BT-50 based Estes Sprint was introduced in 1970. It was advertised as "The First True Competition Model". To see the catalog page, CLICK HERE Very few models had boat tails back ... [Read More]
Estes Sprint XL #7224 Build, Part 2, Tail Cone (2017-02-02)You could cut through the nose and tail cone with a razor saw but I used my break-off blade knife. Repeated scoring and the plastic was separated. The tail cone needs the most work. When first ... [Read More]
Estes Sprint XL #7224 Build, Part 1, Parts (2017-02-03)Well, I screwed that up! This post should have gone up yesterday after the first "Background" post. Here it is, I'll fix the order later. I've wanted to build this one for a while. I picked up two ... [Read More]
Estes Sprint XL #7224 Build, Part 3, Tail Cone Fit (2017-02-03)First up you'll have to widen the low end hole. 200 grit was wrapped around an 18mm casing. Constantly check the fit of the BT-50 engine mount tube. The engine hook slot was widened with a small ... [Read More]
Estes Sprint XL #7224 Build, Part 4, Engine Mount & Kevlar (2017-02-04)Look close at the ends of the tail cone. There is a slightly raised molding lip. I used my sanding block with 220 grit to straighten out the sides. The engine block sits inside the end of the engine ... [Read More]
Estes Sprint XL #7224 Build, Part 5, Fin Shaping (2017-02-06)In the original Sprint kit you had a choice to either airfoil the fins or round the edges. These new instructions say to round just the leading edges. That didn't make much sense given the ... [Read More]
Estes Sprint XL #7224 Build, Part 6, Lugs and Primer Fill (2017-02-07)The launch lugs have to be cut in two. The original smaller Sprint had two lugs only 1/4" long. The lug ends were cut at an angle. This lug is simply cut in two. To get a straight cut, wrap some ... [Read More]
Estes Sprint XL #7224 Build, Part 7, Fin Gluing (2017-02-08)With the lugs glued on the fin marking guide is wrapped. Line up the LL line with the lugs already in place. The engine mount hasn't been glued in place yet. TIP : With the tail cone removed, extend ... [Read More]
Sprint XL and Long Tom Builds on Ebay (2017-02-08)For the next few days, both the finished Sprint XL and Long Tom builds are up for auction on Ebay! The Sprint XL is HERE , The Long Tom is HERE Stop by, make a bid and support the blog! [Read More]
Estes Sprint XL #7224 Build, Part 8, Decals (2017-02-09)The fin grain still showed on two fin sides after the first light white coat. I rubbed in some CWF with a fingertip. The coat was thin so there wouldn't be much sanding. These are all the decal you ... [Read More]
Estes Sprint XL #7224 Build, Finished (2017-02-10)An interesting, easier build. I missed the extra decals that were included in the original BT-50 based Sprint kit. On the right is the catalog version I put together years ago. The cleaner decor is ... [Read More]
Sponsored Ads
