Dishes are done... almost

Well, it may have taken me something like 15-20 hours of fiddling around trying to work out all the new equipment and develop some skill at using it, but I think I have worked out how to make a sanding dish - or at least a way of making a half decent version of one. I tried a few different methods - this is what I ended up using. I think it works best for me.

First of all I plotted out BillM's calculation of the given radius onto 30mm wide x 20 mm thick MDF strips. From that I used nails to plot out the curve, taking into account the width of my steel rule. I also cut the heads off the nails to try and keep it closer to accurate.



Most importantly, I introduced some form of dust management. If you are going to attempt to make dishes, this is a must. To give you some idea, I changed the bag in my standard household vaccum four times today. My shed is trashed from the previous efforts an I fixing up the old vaccum cleaner was well worth the effort.

Below you can see how the steel rule (flexible) is held up by the nails. I use a bearing bit in the router, usinging the steel rule as the guide. When I push the bearing against the ruler it in turn pushes against the nails plotting the curve. Below, you can also see my hightech dust management system in place.



Here you can see how the bearing runs on the ruler... the ruler is pushed back against the nails.



I got carried away and forgot to take some pictures through the process. I will get some detailed photos tomorrow when I make the 15 foot dish. Below is the 30 foot radius dish. I am really happy, some light sanding and I will be home and hosed.



Time taken : 4 hours
Tools used : Router, vaccum cleaner, pencils, rulers, screws, drill, jigsaw, eye/ear/dust protection, etcetera - all of it.
AU$'s spent : Nil