"Help!" for: Fiberglassing, Resin, & Bondo

[Satchmo III]

I saw a video on youtube a while back and it said that you could put a layer of spray glue down first inside the helmet to help keep your fiberglass in place before you resin it. Does this have any affect on the rigidity of the fiberglass or it adhering to the helmet? I just dont know what the glue would due because its another layer between the cardstock and the resin.

I use mat when installing fiberglass. Instead of using an adhesive to keep the fiberglass in place I apply some resin to the helmet before placing the fiberglass piece. This helps the fiberglass stick to the helmet while I use a dabbing motion to apply more resin to the piece to saturate it.

I believe some people do use adhesives to hold fiberglass but I think it is extraneous and by putting resin in first you allow the fiberglass piece to absorb resin from the back and the front.

 

[Katsu]

The glue is not good for the fiberglass at all. It can soak into the fiberglass mat and take the place of the resin, which prevents the resin from actually soaking into the mat fully, which kills the strength of the stuff. It also is a layer between two layers of resin, which prevents them from bonding together like they do. It's very stupid to use glue, Satchmo's suggestion is worlds better. Just be careful when tapping down the mat, as you get resin on your (gloved) fingers, they will start fraying the fiberglass mat as it sticks to you.

 

[Bigbearwayne]

Can someone tell me the difference between bondo resin and bondo resin jelly? Also what one would you recommend?

 

[CoolC]

Can someone tell me the difference between bondo resin and bondo resin jelly? Also what one would you recommend?

I know most of in US use regular Bondo. The most popular brand is 3M. It is paste like and has the consistency of peanut butter. I've never heard of bondo jelly.

For our purpose, bondo paste is what you need. It should be easy to apply than jelly type. Then again I've never seen bondo in jelly format.

 

[Green Theorem]

What would be the best/most durable bondo to resin ratio for making rondo?

 

[CoolC]

What would be the best/most durable bondo to resin ratio for making rondo?

There is no scientific method or what ratio is the best. You just need to try it and see what works. I use about 40% bondo/60% resin. The trick is the rondo should have the consistency of liquid metal (think Terminator T2).

 

[MousieGuy]

I have a small emergency. Actually a big one.

I was resing my helmet at another location, and the inside of the helmet had not fully dried. Because I was outside, I could not smell it and it had been about 10 hours since I set it. When I wrapped it up in a plastic band then put it in a cardboard box in the back of the boot, it started to smell and soon I was getting eye irritation and headaches. The car trip was about 30 minutes long and there was 5 people in the car.

The smell is still in the car and I have been stressed and unable to sleep, I have not told my family that it was a problem yet because they are worse than me under stress. Can somebody tell me if this is a problem so I can break the bad news?

 

[Katsu]

You just need to air the car out. Unless resin leaked into the car, the fumes will disperse over a few days (gotta leave that boot open or cracked though)

Also, it shouldn't take more than 1 hour to become tacky, and then maybe 5 hours tops to become hard. You are in australia so winter is going on there. If the temperature drops below 60F (15.5C) you should consider not doing the resin at all. If it's around that temp, you can do it, but you need to add more hardener than the instructions say. I go for 2-5 drops more than the suggested amount, this means you have less time to work with it, but it won't get ruined by the cold weather.

 

[PhotogenicGuy]

Acetone works pretty darn well.

 

[Cereal Killl3r]

What it sounds like is the resin did not thermally react correctly. This can be due to too low a temp, or too thin a resin coat or a combination of both which has now left the helmet tacky and with a never ending resin odor. Cover the helmet with talc, baby powder or kitchen flour where ever you have applied resin and leave it as such for 24 hrs. This will draw the remaining moisture out of the resin and help rid the smell of the product. As far as your car having an overpowering smell of resin, leave the windows open for the day. Should the smell remain, that means you got some resin in the vehicle somewhere. At that point, I would suggest shampooing the area that the helmet was in.

Hope this helps you out,
Cereal/Dave.

 

[MousieGuy]

Thanks, It's a bit of a releif. Regarding the helmet, It's now fine. The car is aired out.
The day I was doing the resin, I did take that into note. It was about 18 celcius outside.
Anyway, It should be fine and thanks for the support.

When the helmet was finished, I put a primer on it to see where I needed to look out for for the next step, problem is that the helmet is really weak on the part next to the lights. Is there something I can do in the filler stage to make it stronger?

 

[Katsu]

You really need to fiberglass or rondo the inside of the helmet (preferably both)

Resin alone is just to act as a temporary stiffener since cardstock isn't very good at holding the weight of wet fiberglass or rondo.

 

[MousieGuy]

Okay, well. Sadly, I had to dump the resin after use when the MKEP spilled into the container. Now, I noticed that parts of the helmets inside were not completely dry and still sticky after the two days. Should I be concerned?

Also, I want to "Buff" it up a little with the fiberglass mat by using two layers. Problem is, I'm not sure what to do to make it stick, when I was using resin it just got everywhere but on the inside and afterwards, I tried to "Glue" it to the back and it just would not hold. Should I try something else?

 

[CoolC]

Okay, well. Sadly, I had to dump the resin after use when the MKEP spilled into the container. Now, I noticed that parts of the helmets inside were not completely dry and still sticky after the two days. Should I be concerned?

Also, I want to "Buff" it up a little with the fiberglass mat by using two layers. Problem is, I'm not sure what to do to make it stick, when I was using resin it just got everywhere but on the inside and afterwards, I tried to "Glue" it to the back and it just would not hold. Should I try something else?

If resin is mixed appropriately, it should harden without stickiness in 24 hours. If it is still sticky, more than likely you put too little hardener. Your only option to fix it is to mix another batch of resin with proper mixture and put a layer on top. Hopefully this will cause the first layer to harden.

I suggest that you do what Katsu said. If you have a hard time putting one layer of fiberglass, you are going to have a tougher time putting on the second layer. Pour rondo inside the helmet. It is possible to lay fiberglass in on the rondo while it is curing. But I recommend that you place the fiberglass once the rondo is cured.

 

[MousieGuy]

Hmm, Is there any way to do this without me purchasing more resin? Would my filler be enough to lay the fiberglass on? Or could I use some kind of adhesive?

 

[Katsu]

You need the resin.

There is what's called "hairy bondo", which is bondo with fiberglass mat mixed in, but it is still nowhere near as strong, nor as light as fiberglass with resin. All of the accepted methods of hardening involve the resin. Which is good because the resin is the cheapest of the tubs...

The fiberglass mat requires a more liquid material that can soak into it. Filler is more of a dry paste, it doesn't do much soaking in, unless it's clothing!

 

[MousieGuy]

I'll get more resin on Friday and give it a crack. Thanks for the help everyone.

I've primed the helmet, and I accidentally made it too thick. Is it suggested to sand it down then resin the inside?

 

[Katsu]

You shouldn't primer the helmet until after the first layer of bondo, really. You want to sand the whole thing to smooth the rough edges first, and then bondo it. The primer shows where you messed up with the bondo, but if it's on there, it can't hurt anyways, sand that stuff down! You should resin first, before anything else, making sure to mix enough hardener in. Then you want to harden the inside with fiberglass and/or rondo (I say and), then you start smoothing the outside (filler/primer)

If you haven't seen Cereal's videos, they're absolutely worth a gander. The first vid is where you are now:
http://www.405th.com/showthread.php...-Chief-**-A-Step-By-Step-Tutorial-(My-Way)-**

 

[NeoKeth]

Speaking of filler, I just started work in a plastic extrusion factory. We use tiny PVC beads to make our product. Has anyone tried using this as filler? Would the resin get hot enough to melt the PVC?

 

[Katsu]

Rondo can get really hot, hot enough to melt hot glue glue. Straight resin doesn't get too hot though. Trial and error, though, trial and error.