TD has the clamps in his photo's I was talking about, one way that has helped me take out dents from balsa as well as other woods is use a 50/50% denatured alcohol and water mix the water puffes the balsa up and the alcohol helps it to evaporate quickly,also windex will work well also it softens the wood and will swell it up to remove dents I use both methods for removing dents and dings I sometimes get in balsa sheeting, swells them out great, then just a quick sand job to smooth things out.