steve wrote:It probably wouldn't hurt, but I don't. You won't sand the fiberglass, just the epoxy.
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Don't let it scare you - it's not hard to do at all. I think fiberglass work is much easier than the wood work on the teardrops. I really think anyone that can construct a teardrop can do fiberglass work - we just like to make people think we're magic.
Here is the next installment of SAMAS (the Steve'n'Andrew Mutual Appreciation Society)....
Sanding fiberglass does seem to scare some people, but it shouldn't - all fiberglass dusts are inert and only rank as a 'nuisance' in industrial safety legislation here. In contrast many hardwoods (including in plywoods) are bad, bad news - the dust from them is carcinogenic and respiratory protection must be worn. In this case the common assumption that 'man-made' is dangerous and 'natural' is safe is the exact opposite of the truth.
Contact with 'wet' epoxy resin is not good - it can trigger a skin reaction and can lead to epoxy sensitivity, though this is only likely if you use it daily. However gloves should be worn at all times - medical-type vinyl or latex gloves are ideal.
Don't let any of this put you off - these risks are minimal compared to the likely hearing damage from using regular domestic power tools and don't get me started on the risks of using a table saw......
Getting a smooth surface by sanding is a tricky one, and maybe I did overplay the difficulties. However it is my experience that there is a huge range in what different people think is sanding - for some it's harder than scrubbing the deck on a medieval warship (though, generally, without the whipping...) and for others it's less work than dusting furniture.
Here's my twopennyworth:
- Always do whatever you can at any stage to make like easier later - don't slap on epoxy and cloth and then walk away - look for any defects before the epoxy cures and smooth out any runs or drips.
- Apply filler carefully. Get a wide spreader (just a piece of plastic) and work the filler to get it as smooth as possible before it sets - again don't walk away from the job before you're done.
- Use a filler of appropriate hardness. If you chuck some silica into epoxy resin, you'll get a filler that's not as easy to sand as cast iron..... Follow Steve's recommendations on fillers!
- Pick the right time to sand. If you sand too soon (before the resin has cured enough), you'll find your sandpaper clogs really quickly - if so, stop sanding and try again tomorrow. This is a more likely problem in a cool climate.
- Get good sandpaper - aluminium (sorry, aluminum) oxide is the minimum.
- Choose your sanding 'block' to suit what you're trying to do - if you want to make something flat, you need a hard 'block' so that you only sand the high spots. If you're trying to get a gloss finish, then you need a soft 'block' to make contact over all the surface of the block. And, yes, needing to use a variety of backing blocks does mean that trying to combine the terms 'power sander' and 'good finish' in one sentence is a non-starter....
Or
- Decide that you are flexible in your attitude to surface finish, so that what you've done so far is just right. Moving the target is often much easier than any other method......
Andrew
