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Showing posts from February, 2016

Bent laminations?

I saw a piece of scrap offset in my bin that got me wondering about whether to try cutting some thin slices of wood and laminating curved sections. I tried to bend the piece of scrap around an 11" diameter MDF circle I'd made previously and I was quite surprised just how flexible the piece of scrap was. The scrap was varying in thickness, but one outer edge was about 0.15 inches. The photos show how easily it bent, and this was just dry, no steam or water involved. I might try laminating a few layers out of curiosity. scrap and 11"MDF disk test bend

Banjolele rim #3 - glued up finally

After having all three layers done, I decided to try to get the middle layer (shallowest) to size using a router and template, then I would glue all three layers together and machine the outer two layers using the middle layer as a router follower bit against the middle layer. In short this turned out badly, as I broke the middle layer whilst trying to route the inside surface. Fortunately I was able to patch it up, and in the end the patch should be invisible, but I decided at that point that it was probably best to get the three layers glued together before I made an unrecoverable mess of things. glued and clamped I'm not 100% sure how I will shape it yet. Probably router plus jig for the outside and sanding drum for the inside. Part 2 is here

Banjo rim #2 - second layer, a change of tactic

I'm still experimenting with things really, and decided to try a different approach for the next segment layer. This time I thought I'd make a octagon using 45 degree scarf joints. There are a number of reasons why. I'd had difficulty with the mitred angles on the previous layer, and using scarf joints means half the number of angles to using equal angles each side of the block. Half the angles means the cumulative error is going to be less if anything is off (in theory). The wood I have is a not really as deep as I would like, and doing it this way means initially I only need to get one side and one face squared. The other face can be fixed after gluing the segments. I don't have to worry about the length or width of each segment providing they are above the minimum requirement. On the downside, the glue-up is tricker as I found out later. So here is how it works out in sketchup 11 inch segmented rim using 45 degree scarf joints First off, I trued up t

Bracket band Sketchup model #2

I was a bit nervous about 14 shoes being able to handle the tension, so I decided to re-model the bracket band with 18 shoes. This time I left a larder space between two of them to accommodate the neck, then evenly spaced the shoes around the remainder of the circumference. new bracket band model with 18 shoes For comparison, here is the old model. No idea why the colours are reversed, there's probably a logical explanation somewhere. old bracket band model with 14 evenly spaced shoes