It’s been a hard design faze but we are now underway with the Doctors sonic.
Have been using various cnc programs as well as CAM programs, but mach3 is what I’m using on the Sieg mill, that I converted to a cnc for my home workshop to do small jobs like this, there are various CAM packages out there and they very in price, some cost as much as a small car.
As mentioned in a previous post I will be manufacturing some parts on the cnc mill
and others with a rapid prototyping printer.
The prongs will be manufactured from aircraft grade aluminium GR 2024-T5, this grade of aluminium is the same grade that I use to make the UAV’s jet engines and the same grade that I use to make my Rassilon custon Tennant Sonic’s with, oh and the Baker kit sonic.
The prongs that you see been cnc milled, in the above pic was from a sheet of 6.50mm (¼”) plate that had to be milled down to a thickness of approximately 5mm, as the prong on the doctors sonic are 5mm thk.
I used a 2mm end mill that has a cutting depth of up to 8mm, I used a feed rate of 400 mm/min with a spindle speed of 2400 rpm and a passing depth cut of 0.3mm or 300 microns (0.0039”)
I do intend on making two (2) sonic with some extra machined parts just in case accidents happen on the way, the plan is to make one complete part per month or more with the cnc, with other parts on the rapid prototyping printer been made quicker.
Once the parts had been cnc milled the next step was to mill the slot on the top section of the prongs, as to the workshop manufacturing drawings, that I have been doing over the last 3 month, the drawings call for a 3mm slot 1mm or 1000 microns deep.
The prongs still need to have a small hole drill at the back end of the prongs, but I will do this later on, as well as a 1mm hole at the front of the prongs, this will allow me to install a 1mm pin that holds the halo in place.
Next item on the workshop manufacturing drawings was the halo, and for this item I used hollow brass bar, the circular groove in the inside of the halo is 3mm x 3mm deep and the end mill used in cutting this was a 3mm cutter.
I had to come up with a jig to hold this all in place, and here it is, as you can see in the pic this was a very lazy way of doing the inner slots and most of the milling work.
There are 4 circular slots located on the centre flange section of the brass halo, for this I will use the cnc mill , I could have use the 4th axis, but setup is a painfull job for just a hadfull of parts, and the way I have it worked out will make it possible to and also quicker to setup next time to make the same type of halo, as the jig will have the X,0 Y,0 make located on the jig for future reference.
