Franny
01-02-2007, 01:28 AM
Hi All,
I am waiting for a bonus from work to finish me .40 size Taube, so I thought I would take a bit of time and build that 1/2A Blazer I've had for a while. For those that aren’t familiar, the Blazer is an old Goldberg free flight kit from the late 60'-early 70's designed for .049. I built a couple as a kid, but never flew one. I have had great success with my 1/2A Viking (also a Goldberg free flight kit) which I electrified and converted to RC so I've been itching to try my hand at the Blazer. I just finished it today and I thought I would share some photos. I'll have to wait for a little warmer weather here in Denver to melt a bit of the snow before I can maiden it, but all checks out so I'm betting it will go well.
The construction was pretty simple and very "Goldberg". My biggest concerns were battery placement, servo placement, access to both, and most of all, balance. the balance is a bit complicated on these FF jobs because of the lifting stab, their short nose and long fuselage. The plans called for a balance point about 2/3s of the way back from the leading edge - super far back. The Viking's balance point is actually behind the point on the plans and still flies great! I believe the model compensates by changing it's speed which is the other factor in the balance. With a non-lifting stab, the speed doesn't affect the balance point, but with these guys, the balance is speed dependant and therefore, I think, a little less sensitive actually. At any rate, the fuselage is so small, that there are really only a few possible configurations for battery and servo placement and access. I am running an E-Flight 370 outrunner with a CC ESC and a three cell 900mAH lipo. This is the same power system on the Viking which is a tad thin on performance. It will get upgraded to a 400 motor and a 1350mAH lipo very soon.
Here are a couple photos of the construction including the horizontal stabilizer with its split elevators. As with the Viking, the hinge line for the two elevators are not co-linear so I had to run two control rods; one for the right and one for the left. I hinged the rudder on the original glue line of the fin with thin plastic, pinned hinges. I also beefed up the dihedral braces using thin ply instead of the specified balsa and using super thin ply to brace the leading and trailing edges. I also sheeted the very center of the wing to protect it from the rubber bands that are use to attach it to the platform. Other than that, it was pretty much as the plans directed.
It was great fun to build and I was able to use spare parts and covering I had laying around so there was no cost outlay. The kit came from Ebay for about $20. I saw one go recently for about $35 They are getting a bit more rare so they may get a little more expensive. The original price was $6.95 I think.
Let me know what you think!
Thanks,
Franny
I am waiting for a bonus from work to finish me .40 size Taube, so I thought I would take a bit of time and build that 1/2A Blazer I've had for a while. For those that aren’t familiar, the Blazer is an old Goldberg free flight kit from the late 60'-early 70's designed for .049. I built a couple as a kid, but never flew one. I have had great success with my 1/2A Viking (also a Goldberg free flight kit) which I electrified and converted to RC so I've been itching to try my hand at the Blazer. I just finished it today and I thought I would share some photos. I'll have to wait for a little warmer weather here in Denver to melt a bit of the snow before I can maiden it, but all checks out so I'm betting it will go well.
The construction was pretty simple and very "Goldberg". My biggest concerns were battery placement, servo placement, access to both, and most of all, balance. the balance is a bit complicated on these FF jobs because of the lifting stab, their short nose and long fuselage. The plans called for a balance point about 2/3s of the way back from the leading edge - super far back. The Viking's balance point is actually behind the point on the plans and still flies great! I believe the model compensates by changing it's speed which is the other factor in the balance. With a non-lifting stab, the speed doesn't affect the balance point, but with these guys, the balance is speed dependant and therefore, I think, a little less sensitive actually. At any rate, the fuselage is so small, that there are really only a few possible configurations for battery and servo placement and access. I am running an E-Flight 370 outrunner with a CC ESC and a three cell 900mAH lipo. This is the same power system on the Viking which is a tad thin on performance. It will get upgraded to a 400 motor and a 1350mAH lipo very soon.
Here are a couple photos of the construction including the horizontal stabilizer with its split elevators. As with the Viking, the hinge line for the two elevators are not co-linear so I had to run two control rods; one for the right and one for the left. I hinged the rudder on the original glue line of the fin with thin plastic, pinned hinges. I also beefed up the dihedral braces using thin ply instead of the specified balsa and using super thin ply to brace the leading and trailing edges. I also sheeted the very center of the wing to protect it from the rubber bands that are use to attach it to the platform. Other than that, it was pretty much as the plans directed.
It was great fun to build and I was able to use spare parts and covering I had laying around so there was no cost outlay. The kit came from Ebay for about $20. I saw one go recently for about $35 They are getting a bit more rare so they may get a little more expensive. The original price was $6.95 I think.
Let me know what you think!
Thanks,
Franny