If there isn't alot of missing material or a large gap to be bridged, its pretty easy to fill a gash yourself with a heat gun or a torch if you're real careful. Ask around at local shops to see if any of em have plastic around from warranties or other broken boats. Heat up the boat slowly and extra plastic slowly until they get tacky. Then use a putty knife to squish it all together. Fill the gash with more material than you'd think you need, and be sure to overlap the area by about 25%. After it all cools down, use sandpaper or a knife to trim the area smooth. Just remember to take it slow and don't use too much heat or you'll just make it worse. Hope this helps.
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