Bondo help (not curing properly)

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Shinnentai
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Bondo help (not curing properly)

Post by Shinnentai »

Had my first experiences with Bondo (the two-part body filler kind) recently. What is the normal curing cycle for Bondo? Are there any conditions that might significantly inhibit curing (cold, humidity, etc)?

I laid the first few applications the day before yesterday. It set up within the first half hour, but now two days later although hard, it's still a little fumey and tacky to the touch. The very first application I did I know was undermixed, but I've been careful since to put in a good amount of hardener and mix very thoroughly. The instructions and everything else I've read suggests that it should be fully cured in under two hours, but that doesn't appear to be what I'm getting.

Any idea what I might be doing wrong?

What happens if one uses a little less hardener than normal? A little more? Would that just mean slower/faster curing, or would it affect it in larger ways?
"Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized."
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Johnnycrash
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Re: Bondo help (not curing properly)

Post by Johnnycrash »

Shinnentai wrote:Any idea what I might be doing wrong?
You did nothing wrong. Bondo is like that. Give it a swipe with the sandpaper, and you will find it is perfectly fine under that tacky surface.
What happens if one uses a little less hardener than normal? A little more? Would that just mean slower/faster curing, or would it affect it in larger ways?
A little less hardener, and it will cure a little slower, giving you a tad more working time. It does not affect the bondo. Unless you put to little in, of course.

As long as the bondo is firm, you are ready to go. And it will smell almost forever. It's just the way it is.
John Fleming
I know that's not what the instructions say, but the kit's wrong anyway.
Bomech1
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Post by Bomech1 »

You didn't clearify your application but take my word AVES!
Brian
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Johnnycrash
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Post by Johnnycrash »

Brian Oakley wrote:You didn't clearify your application but take my word AVES!
Yes, AVES is great... at about 15x the cost. When you need to fill a hole, or a large area, cheap harware store bondo is the best bet. It sets up fast, can be applied repeatedly, and will take a fine surface finish. A 1 gallon can?? $18.00 CDN.
John Fleming
I know that's not what the instructions say, but the kit's wrong anyway.
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Mr. Badwrench
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Post by Mr. Badwrench »

The only time I've had problems with Bondo not setting up properly was when I didn't mix in enough catalyst. I guage the mixing ratio by color, if it isn't red enough I add more catalyst. I usually mix it pretty hot, to where it loses it's workability within five minutes or so. I haven't had any problems with tackiness that way.
I speak of the pompatous of plastic.
Shinnentai
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Post by Shinnentai »

Thanks for the replies all! Glad to be reassured.

Started doing some file shaping, and that got rid of the tackyness.

I've been itching to give Aves a go, but I can't afford it for this project. It's a wee bit on the large side, and that puts bondo in a position of superior economy. Truth is, If I could afford to buy that much Aves right now, I'd buy one of Coby's mini-G's instead (I really want one, but I haven't got the spare $50).

I'm hesitant to go into detail at this point, other than that I'm trying to develop a cheap & relatively simple way of creating large, realisticly detailed 1:1 subjects. I'm skinning bondo over a core of wadded aluminum foil, which will then be carved to shape/detail rather than sculpted.
"Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized."
-Ly Tin Wheedle
shrugger
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Post by shrugger »

Bondo is great stuff.
If it's mixed to a nice light pink color Then its just about right.
And if you'll be using a bunch of it like Alex here
http://www.alexkung.com/scale/serenity/cmain.htm
Then its allot easier on the wallet.
"Some people juggle Geese"
-Wash
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Maschinen Krueger
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Post by Maschinen Krueger »

I always mix the Bondo hot. I put more hardener than I should. YOu can alwyas buy another tube pf hardener.

Bondo can also be used for small stuff too:

http://www.starshipmodeler.net/cgi-bin/ ... hp?t=30886

The fast setting time is what does it for me. Sometimes I'm not mixing up more than a teaspoon of the stuff to patch up small marks or pin holes. Use a good surfaces like Mr 500 or an automotive laq. primer to fill in the surface.
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