Doug Foster
Active Member
I have recently completed building the fabulous Estes 1:100 S1B kit. I followed the youtube video by master builder James Duffy (rocket.aero) who is a tremendously valuable resource. His approach differs from the kit instructions significantly. In particular, all parts are painted prior to assembly which results in beautiful detail for display purposes.
The last step is the plastic fin attachment. This is done with plastic cement applied to a small tab at the top of the fin. Cement is also applied to the back of the fin which attaches to the already painted shroud. Upon inspection, one of the fins had detached from that back bond but was still attached by the tab. Further inspection found a couple other fins had loosened and while testing each one gently one completely fell off (tab bond failed as well). Suddenly this started looking like the Space Shuttle when the tiles were falling off at night in the hanger!
This led to a series of disastrous rework attempts. First I put a fillet of Tamiya extra thin cement along the back seam. This adversely reacted with the paint (the entire rocket is painted with Tamiya spray paint (for plastics). Next I tried a fillet with Zap a Gap CA glue. This had even a worse reaction with the paint. That resulted some black paint completely coming off. So I masked off the rocket and sprayed the small section where the paint had come off. Unfortunately I placed some of the masking tape over the decals and in the removal I destroyed one of the large United States decals and 2 of the SA-206 decals. This was an all time low for the project. I have no confidence that even the attached fins would survive lift off let alone a landing. This resulted in the grounding of the S1B and all launch schedules suspended.
Current recovery plan is as follows. I will attempt to remove the damaged decals-I see that using the micro set solution has been successful. I was able to locate replacement decals on eBay and those have been ordered (not a guarantee these are correct but they look correct). The fin that completely fell off was reattached using the same liquid cement on the tab but with a bit more glue. An experiment was performed over night where I used Gorilla dry clear wood glue as a fillet along the fin joint. This glue does not react with the paint. It appears to work on one fin and that method has been just applied to all 8 fins. It dries clear but you can see a haze on the black paint if you look closely. Will do some light stress testing on these.
So all of this leads me to some observations and questions:
1. There could be a difference between a "display build" and a "launch build". Kit instructions is gluing unpainted surfaces-but there is no way you get the beautiful paint detail if you painted after this model was built.
2. Don't ever use liquid cement on painted surfaces!
3. Don't ever put masking tape on a decal! (unless you have sealed the rocket with clear coat-which I have not tried yet and is another topic!)
4. Is there a reliable method of attaching fins to a pained tube?
5. The fins on this model, even when attached, appear extremely delicate. I can't believe they would survive a landing. Does anyone have experience with these fins structural integrity? Assuming a few break, are there exact replacements?
The last step is the plastic fin attachment. This is done with plastic cement applied to a small tab at the top of the fin. Cement is also applied to the back of the fin which attaches to the already painted shroud. Upon inspection, one of the fins had detached from that back bond but was still attached by the tab. Further inspection found a couple other fins had loosened and while testing each one gently one completely fell off (tab bond failed as well). Suddenly this started looking like the Space Shuttle when the tiles were falling off at night in the hanger!
This led to a series of disastrous rework attempts. First I put a fillet of Tamiya extra thin cement along the back seam. This adversely reacted with the paint (the entire rocket is painted with Tamiya spray paint (for plastics). Next I tried a fillet with Zap a Gap CA glue. This had even a worse reaction with the paint. That resulted some black paint completely coming off. So I masked off the rocket and sprayed the small section where the paint had come off. Unfortunately I placed some of the masking tape over the decals and in the removal I destroyed one of the large United States decals and 2 of the SA-206 decals. This was an all time low for the project. I have no confidence that even the attached fins would survive lift off let alone a landing. This resulted in the grounding of the S1B and all launch schedules suspended.
Current recovery plan is as follows. I will attempt to remove the damaged decals-I see that using the micro set solution has been successful. I was able to locate replacement decals on eBay and those have been ordered (not a guarantee these are correct but they look correct). The fin that completely fell off was reattached using the same liquid cement on the tab but with a bit more glue. An experiment was performed over night where I used Gorilla dry clear wood glue as a fillet along the fin joint. This glue does not react with the paint. It appears to work on one fin and that method has been just applied to all 8 fins. It dries clear but you can see a haze on the black paint if you look closely. Will do some light stress testing on these.
So all of this leads me to some observations and questions:
1. There could be a difference between a "display build" and a "launch build". Kit instructions is gluing unpainted surfaces-but there is no way you get the beautiful paint detail if you painted after this model was built.
2. Don't ever use liquid cement on painted surfaces!
3. Don't ever put masking tape on a decal! (unless you have sealed the rocket with clear coat-which I have not tried yet and is another topic!)
4. Is there a reliable method of attaching fins to a pained tube?
5. The fins on this model, even when attached, appear extremely delicate. I can't believe they would survive a landing. Does anyone have experience with these fins structural integrity? Assuming a few break, are there exact replacements?