Proline help please

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dixontj93060

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I have used the high-temp Proline for a number of years, but as I reflect back, each time use was on a high-performance minimum diameter rocket that was painted with high-temp paint or on a black body like Profusion or CF so tiny imperfections were never really seen. I am just about finished with a modified RW G3 and as can be seen in the attachment, it has a red body. The fillets are decent, but certainly not perfect. I'd like to do some minor sanding, but have some trepidation as on previous builds I know if I screw up the fillet will turn silver-gray. My inclination is just to be extremely careful and use a Dremel with a grind stone, but my question is, what are my options here? Can you sand these fillets and then recover? For instance will they "shine up" after brushing with epoxy resin or applying a clear coat of some kind? Or are they instead gray forever and you'd have to paint them black to fix them? I would expect those that build fiberglass rockets more than I do, like CJ or Griffin, know the answer on this. I'd appreciate any help you may be able to give. Thx.

IMG_2206.jpg
 
Sand them down then, apply another coating of it.
It's a metalized epoxy which gives you the shiny speckles of metal when sanded.


JD
 
Sand them down then, apply another coating of it.
It's a metalized epoxy which gives you the shiny speckles of metal when sanded.


JD

I don't know about that? It isn't bad now. Just a few edges to clean up. Another coat may leave it looking worse.
 
What if you lay a test bead on some scrap, sand it, then try clear coating it? I wonder if the clearcoat would bring the black back???
All the fillets I have with 4500 have been painted, or I'd do it myself.

Adrian
 
Hey Tim....

I can tell by looking, they settled in "flat" after you smoothed with tool. I also know how anal you can get with your finished product. When you sand these they will turn silver gray & nothing will make them black again other than re-coating with either dyed black epoxy or more Pro-line or painting black[but that's rookie BS]. Sooooo.... knowing you and the above....simplest best solution I can offer is.

Tape them off again, so you don't scratch tubes or fins.
Sand till you happy with result. If tape scuffed or damaged replace.
Use original tool and re-pull with fresh epoxy.
Results will be stunning.
Yes I have done this when wanting "perfect" fillets [Proline] It's really not that bad doing it a second times, goes really fast & is worth it.

PS if it's only tiny touch up here and there, I have done that and used a sharpie to "blacken'' the touched up area's then clear coat hides the whole she-bang
 
Hey Tim....

I can tell by looking, they settled in "flat" after you smoothed with tool. I also know how anal you can get with your finished product. When you sand these they will turn silver gray & nothing will make them black again other than re-coating with either dyed black epoxy or more Pro-line or painting black[but that's rookie BS]. Sooooo.... knowing you and the above....simplest best solution I can offer is.

Tape them off again, so you don't scratch tubes or fins.
Sand till you happy with result. If tape scuffed or damaged replace.
Use original tool and re-pull with fresh epoxy.
Results will be stunning.
Yes I have done this when wanting "perfect" fillets [Proline] It's really not that bad doing it a second times, goes really fast & is worth it.

PS if it's only tiny touch up here and there, I have done that and used a sharpie to "blacken'' the touched up area's then clear coat hides the whole she-bang

Well, OK, the expert has spoken... And pretty much what JD said too... I'm assuming the second time around maybe a slightly bigger radius and wait a bit longer before pulling the fillets so they won't flatten/sag, right?
 
Well, OK, the expert has spoken... And pretty much what JD said too... I'm assuming the second time around maybe a slightly bigger radius and wait a bit longer before pulling the fillets so they won't flatten/sag, right?

Yeeeuuuup...

except...... I bet if you place your tool on fillets and view from aft end, there will still be plenty of clearance & no need for a larger tool/radius.

Just use same and do over. Also sagging should not be a problem since you're just coating them.... however when doing "new fillets" I always let epoxy sit 10-15 minutes after laying in V-groove to stiffen up a bit, before pulling them out. Keeping in mind how long you wait is totally ambient temperature related.
 
Well, here's were I'm coming out on this... I did some touchup/cleanup with 150 grit to remove any epoxy drips from assembling the fin can and/or applying the Proline 4500 fillets. I then used 220 grit and sanded down the whole booster along with the fins and fillets. Then cleaned well with acetone. After getting it cleaned up and looking at the fillets, I didn't really see that it was any grayer than how CF typically looks after sanding--just the dull gray-black. I also still feel pretty comfortable with the fillet shape and they do look better after sanding off all the stray edges. Soooo... I decided to try Adrian's step and apply some clear coat before moving into applying another layer of Proline. Two quick coats of Future in one spot just to test. This picture is taken after the Future dried (it is not wet). Personally, I think this looks fine. Fillets are black. This is not a showcase rocket anyway. It is really going to be a workhorse rocket; heck, it only cost $99 on the Hump Day special. What do you say? I think I'm going to call it done (well, not done; I'll clean up with ammonia and put a full coat on properly, but you know what I mean.)

IMG_2245.jpg
 
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Nice work. Fly it.

One nice thing about the future finish is that you can easily strip it and start over, or simply recoat any time. Just be sure to let it dry in as dust free an environment as possible, since it's a dirt magnet while drying (ask me how I know).
 
One nice thing about the future finish is that you can easily strip it and start over, or simply recoat any time. Just be sure to let it dry in as dust free an environment as possible, since it's a dirt magnet while drying (ask me how I know).

Yes, I'm a long time Future addict. :)
 
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