Advice on Bondo-Hair; Practice Piece Ahead **semi-pic-heavy**

[ShadowCharizard]

So I found this Bondo-Hair in the store, and I figured that it'd be more useful than regular Bondo. More durability / strength and whatnot. However, it didn't occur to me that the Bondo would actually have fibreglass strands mixed into it, therefore being more difficult to work with. I don't really like working with it or how it looks. It's not supposed to have this many holes and look this rough, right? I feel like I'm using it incorrectly. How many of you have dealt with Bondo-Hair?

I began sanding half of the helmet to see how much of a difference it would make.

Thank god this is just a practice piece...!

 

[ShadowCharizard]

Bump

Guess I'd ought to learn when this board is most active before I go posting threads all willy-nilly.

 

[Frozensnot]

Yeah...that stuff you used probably should have been used on the inside of the helmet. Use it as you would like slushing rondo and you have a pretty stirdy inside! You have a lot of sanding to do, but now you know not to use it on the outside!

And always have patience, we dont ignore people intentionally. Some Threads seem to dissapear off in the vast space of the internet.

 

[ShadowCharizard]

Sanding...lol yeah right. Now that I know this Bondo-Hair isn't meant to replace proper Bondo, I'd rather not waste my time working on this helmet any further. I've rondo'd with this stuff, and it is good, but a little brittle for my liking. Maybe I should glue down the fibreglass cloth, then slosh with hairy rondo? I dunno...

Do any other users have experience with this super-strong Bondo? I'm still very open to tips.

 

[Katsu]

We spoke about this last month. I am glad you experimented, but sorry it turned out badly, probably shouldn't experiment on the WHOLE helmet next time!

Hairy bondo is brittle because the bondo doesn't soak into the fiberglass, and there's not a cohesive fiberglass pattern in the hairy bondo. It's the woven nature of fiberglass, and the resin soaking into it, that make it so strong, and you get neither of those with hairy bondo. If you want to keep using it, I'd only use it on the inside as rondo stock. Don't glue down the fiberglass though, just use a dab of resin to hold it down. Glue is just another chemical being added to the mix, and it might not do anything, but it easily can reduce the strength of the fiberglass, since the glue is soaking into the cloth instead of resin which then is just sitting on top. If you want a good mix pattern, I like to push the layered hybrid method. Mix your hairy bondo with resin and slosh it inside the helmet. Once it dries, lay two layers of fiberglass and resin OVER the rondo (when looking inside the helmet, this means the fiberglass would be the closest material to your face). The fiberglass will reinforce the rondo, but you'll still get the sanding and gap filling benefits of rondo covering the inside of the helmet first.

 

[ShadowCharizard]

Hm, some great tips there. It's nice to know that the hairy bondo wasn't a complete waste of my time and money. I never thought of putting fibreglass over rondo for that extra support. I was never planning on using (or even painting) this practice helmet, anyway. I couldn't imagine my devastation if I used this stuff on a proper pep...!

And for others who may also be reading this for advice, the spray glue I have does not affect the efficiency of the fibreglass resin. It's a great way to keep the fibreglass down when adding resin!

 

[Admiral Tiberius]

Hope it didn't set you too much back, bondo isn't exactly the cheapest stuff around. Glad to hear you aren't totally devastated haha.