x30ffx's bondo adventure, pt.2 (I got questions!)

[x30ffx]

Hello guys,
after being out of commission for a whole week being sick, I'm slowly getting back into the groove.

I have but many questions:

Most importantly,

This is what most of the back top of my piece looks like. It's hideous; the bondo edges peel up and it's very hard to sand down. The primer does not cover it up, but agglutinates at the edges. Ideally, it should be absolutely smooth and flat. How can I do that?


how do I get rid of that huge resin drop? it's hard to sand off and I'm afraid to chip it off with a screwdriver. Is it safe? (photo is left side up)


The primer is leaving some holes here and there, what's going on here? should I stand further away as I spray it? (I think i need to refer to volpin's painting book)

Thanks for answering my past questions! cheers to more answers

 

[eiros]

what kind of bondo are you using? also are you adding enough hardener to it? also to get rid of the resin spot i would use the sanding drum on a dremel or even a mouse sander/handsander

 

[FlyinPhil]

Sorry to be the bearer of bad news, but you've got lots more sanding to do! You layed your bondo on a little too thickly, so it's going to take some elbow grease to sand it down! Ideally you want your bondo to go on less than 1-2mm thick. If it is clumping as you lay it on, that means it is hardening too fast and you should make another small batch. Sanding is the only thing that will make it flat.

Sanding will also take down that resin drop, it will just take some effort. I'd recommend using 80 grit for that, as well as on bondo clumps or areas that need lots of material removed. Then work your way up to 320 grit before painting.

As for the primer leaving holes... primer doesn't fill holes. High build primer will fill small scratches ( by that, I mean scratches left by 200+ grit sandpaper), but it will not fill any more than that. You need to fill and smooth those holes with bondo if you want a smooth surface in that area.

 

[Meatwad]

Phil is right, you have to sand it smooth. Start with an 80 grit paper to knock a lot of the imperfections down. Once all your left with are small pits, and i mean very small pits, you can use spot putty and sand that down with a higher grit sand paper. I wouldn't reconnect applying anymore bondo until you have a mostly smooth surface.

Just to give you an idea, i spent 4-5 hours sanding resin imperfections on 1 bicep before it was ready for paint. I spent another 5-6 hours sanding and applying bondo to my grenadier shoulder and it still needs a decent amount of work. This process is one of the most important parts of this whole process. This is what makes your armor look like armor and not folded paper. Take your time. Work in small areas.

Also, watch this video: https://youtu.be/CcotY9s5Zjw

Dave is amazing. A lot if what i learned about bondo and pepakura i learned from him. He is very good at what he does and does a wonderful job explaining the processes.

Hopefully this helps you.

 

[x30ffx]

Phil is right, you have to sand it smooth. Start with an 80 grit paper to knock a lot of the imperfections down. Once all your left with are small pits, and i mean very small pits, you can use spot putty and sand that down with a higher grit sand paper. I wouldn't reconnect applying anymore bondo until you have a mostly smooth surface.

Just to give you an idea, i spent 4-5 hours sanding resin imperfections on 1 bicep before it was ready for paint. I spent another 5-6 hours sanding and applying bondo to my grenadier shoulder and it still needs a decent amount of work. This process is one of the most important parts of this whole process. This is what makes your armor look like armor and not folded paper. Take your time. Work in small areas.

Also, watch this video: https://youtu.be/CcotY9s5Zjw

Dave is amazing. A lot if what i learned about bondo and pepakura i learned from him. He is very good at what he does and does a wonderful job explaining the processes.

Hopefully this helps you.

Cereal Killer's stuff is always amazing. I can't even imagine what I would do without him as well! I'll keep at the sanding. I'm going to try it!

- - - Updated - - -

Sorry to be the bearer of bad news, but you've got lots more sanding to do! You layed your bondo on a little too thickly, so it's going to take some elbow grease to sand it down! Ideally you want your bondo to go on less than 1-2mm thick. If it is clumping as you lay it on, that means it is hardening too fast and you should make another small batch. Sanding is the only thing that will make it flat.

Sanding will also take down that resin drop, it will just take some effort. I'd recommend using 80 grit for that, as well as on bondo clumps or areas that need lots of material removed. Then work your way up to 320 grit before painting.

As for the primer leaving holes... primer doesn't fill holes. High build primer will fill small scratches ( by that, I mean scratches left by 200+ grit sandpaper), but it will not fill any more than that. You need to fill and smooth those holes with bondo if you want a smooth surface in that area.

Looks like I'll be burning through a lot more 80 grit! The top front is actually smooth to my liking, but i need to fix the back center left, and right. I'll keep sanding!