How do I finish? Gel, bodyfiller, other?

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#1

I am making a back for my NEV (neighborhood electric vehicle). I set it up with styrofoam and filled in the curves with expanding foam. Then I glassed the outside with 8oz fg and epoxy.

Now I need to make it smooth, but I’m scared that when it flexes, whatever I use will crack. I was planning on using bodyfiller, but will that crack?

Here are some pics.

I also am making this so that I can easily take it off and put it on when the weather is bad. So I wrapped the fg over the rollbars so I can fasten it down with something. The only thing I can thing of is drilling holes and tapping them and using regular bolts. There has to be something better (or cooler). Any suggestions?

Thanks

BTW - I AM planning on cutting out a window hole and putting some sort of lexan or plexiglass so I can see in my rear view. And I’m also going to glass the inside.

#2

body filler will crack if it gets thick, you can always put another layer of glass over the filler to prevent it from cracking. you could use Dzus fasteners to hold the panel in place, very quick removal and pretty cool

#3

IMO, you should use what you’re making as a mold. It will be heavy, and hard to get a smooth finish.
When you finish sanding and it’s smooth and glossy, wax it and lay up some fiberglass on the inside. At several layers, with a core in between. Pop it off, and you have a strong lightweight cover. Throw away all the heavy stuff that’s on there now.

#4

Are you saying - use THIS as a mould – or make a mould OFF this?

#5

Keep it simple, use that as the mold. No point in making a mold for 1 part.
Make the inside of it perfectly smooth and glossy, and lay up from the inside. When cured, pop it off and the side that faces out (where its appearance matters) will be nicely finished.

#6

Thank you.