Bondo Alternative: Epoxy Resin & Baby Powder.

[Knowone251]

So I hate using bondo, and have been constantly looking for replacements of any polyester based products in my shop. I have been using epoxy based wood fillers, which are great, but I wanted something thinner. After doing some searching I tried baby powder as a filler and found that it mixes well and sands easy.

 

[lharles]

Well, I don't know that I've ever wanted to make something smell like a baby's behind, but good info nevertheless. Good video!

 

[NormanF]

I was sure that the way you were mixing it you would have a lot of bubbles and pin holes to fill after you sanded it.

 

[Knowone251]

I was sure that the way you were mixing it you would have a lot of bubbles and pin holes to fill after you sanded it.

Ya, I was in a bit of a rush. At some point I'll get my degassing chamber set up. Although, there were not as many pinholes as I was expecting.

 

[Killtime]

I'm a wood putty and polyester resin man myself Cheap, affordable and tough.

 

[Knowone251]

I'm a wood putty and polyester resin man myself Cheap, affordable and tough.

I've heard good things about that mix, I just don't like polyester. But to each their own! From what I've read, most people believe that Bondo is just polyester resin and talc. You might want to give that a try, see how it compares to the wood putty mix. If you do, lets us know!

 

[Killtime]

The 405th call it "muddy". I used to make a runny mix but I hated the brittleness. Also become too hard to sand if you believe, I now do a 70/30 putty/resin cut. Have not really used it in a long time as I will usually just use the wood putty as is for detail/filler work.

 

[narutoishere]

I agree. Bondo overkills on smaller projects, and it takes "forever" to sand with a dremel. For plastic modelling, I use JB weld putty and nail-hole filler for small area fix. It is easy to sand with sandpaper, and is paintable.

 

[HMS Mike]

You can use baby powder and cyno as well.

 

[Quill]

Is there any reason that you can't use (or why it would be bad to use) fine sawdust instead of baby powder?

I've occasionally used epoxy-mixed sawdust for fixes and fills in carpentry-related items, but it never occurred to me to use it as a bondo substitute for props before. Feasible, or not?

Useful vid anyway, though, so many thanks.

 

[Killtime]

For filling in very fine details or holes, a small batch of resin and any powder to fill the hole will do I've found. Not sure about sawdust, it would have to be fine naturally but I would assume anything dust like can do the job.

 

[p0rtalman]

Talc (baby powder) is a commonly used filler for most types of resin, I buy it in bulk for mixing up my own bog and gel-coat.
Works great with 2 part epoxy (Araldite) to make a paste. Just don't mix up too much and leave it in the cup, it will set things on fire if you are not careful (I speak from experience on that one )

 

[joberg]

TFS that little trick (didn't know you could do that)..I use, sometimes, crazy glue and baking soda: very hard to sand:cry

 

[Darth Lars]

The only baby powder in the local convenience store/pharmacy has some moisturising agent in it also...

Did I mention that I mix metal powder with epoxy... If the bare metal takes gun blue or other chemical treatment, the metal putty does too. It is almost the same as cold-casting - I also use colloidal silica to prevent it from running. It looks grainy if the metal grains are too large, though.

 

[p0rtalman]

The only baby powder in the local convenience store/pharmacy has some moisturising agent in it also...

Did I mention that I mix metal powder with epoxy... If the bare metal takes gun blue or other chemical treatment, the metal putty does too. It is almost the same as cold-casting - I also use colloidal silica to prevent it from running. It looks grainy if the metal grains are too large, though.

Anywhere that sells moulding and casting supplies should have industrial Talc as well, cheaper than buying it as baby powder and its designed for these kind of uses.

 

[Killtime]

My Fibreglass supplier stocks talc in wicked large amounts, so as long as you ask around you should find it. I think it was 5kg for $10 for me.

 

[mikoyan99]

This may be playing with fire slightly, but has anyone tried using Jesmonite powder as a filler in other resin systems? To the best of my knowledge it's gypsum, but I don't know what else is in there. I have a tub of the powder left over, but none of the acrylic liquid. The resin i'm using is casting polyurethane. My gut feeling tells me it'll set ok, but reduce the longevity of the finished product - would be curious to hear if anyone alse has tried it though.
-Matt