Phenolic drilling
Posted: Tue May 10, 2016 9:59 pmWhen making the mounting blocks for the aileron and rudder and others, I first used a Dremel end mill and made a flat spot so the drill wouldn't walk, then #40 pilot hole the whole way through.
Next I used a Forstner drill and drilled down only about 1/4 inch. Only going down 1/4" will keep the drill centered later in the drilling sequence. Since the phenolic is very hard I, I wanted to remove as much material as possible for the Forstner drill so I next up drilled the hole in steps to 9/32, which is the largest drill I could use in my drill press, without moving the table down which would lose the center position.
Finally, I completed the hole with the 1" Forstner bit, running dry but using my shop vac to keep it clean to reduce heat build up.
To make a perfect fit for the rudder pedals (and other parts requiring phenolic blocks) I used a 3/4 sanding drum to slightly enlarge the hole, trial fitting frequently to get the perfect fit. It took less than 30 seconds per hole to remove enough material.
Next I used a Forstner drill and drilled down only about 1/4 inch. Only going down 1/4" will keep the drill centered later in the drilling sequence. Since the phenolic is very hard I, I wanted to remove as much material as possible for the Forstner drill so I next up drilled the hole in steps to 9/32, which is the largest drill I could use in my drill press, without moving the table down which would lose the center position.
Finally, I completed the hole with the 1" Forstner bit, running dry but using my shop vac to keep it clean to reduce heat build up.
To make a perfect fit for the rudder pedals (and other parts requiring phenolic blocks) I used a 3/4 sanding drum to slightly enlarge the hole, trial fitting frequently to get the perfect fit. It took less than 30 seconds per hole to remove enough material.