Hullo, I just finsihed repairing a similar sounding instrument although this one had a scale length of 18 & 1/16". An arched back and made of multiple pieces. All the staves were loose and it was quite a job to get them all back together. I didn't use a mold as the curvature of the pieces was still intact. After removing them I reattached them all to the neck and heel blocks. Had to make some new black inlay strips in between and increased their width by about 8 to 10 thousanths. This took care of some wood shrinkage that had occurred. I then used cheesecloth attached to the inside of the back and coated it with hide glue. This acts as a pretty good bracing and strengthening system as was used on the old bowl back mandos.When I got it up and runnig it was wonderful. Put it in Mandola tuning and it sounded great. If you have more questions email me through my website at : http://www.kudzupatch.net