Pager testing Aeronutz style
Generally Speaking 1 Aug 04
MK04S 13 Ohms, direct drive, vac formed prop, Dia 30mm, 8.5 to 9 thou thick tip width = 3mm. 3.3v = 118mA 0.75g of thrust, stall curent = 220mA. 4.7v = 185mA and 1.0g thrust, bottom left photo
As below but leading edge cut back to give 3mm wide tip. 3.3v = 1.0g thrust at 132mA. 4.7v = 1.5g at 195mA
MK04S 13 Ohms, direct drive, vac formed prop, Dia 35mm, 8.5 to 9 thou thick tip width = 5mm. 3.3v = 140mA 1g of thrust, stall curent = 220mA. 4.7v = 215mA and 1.5g thrust
As above but tips cut down to 4mm (left photo below). 3.3v = 0.50g thrust at 133mA. 4.7v = 0.9g at 192mA (too fine a pitch, maybe the blades are twisting)
Didel Pager Motors
MK07 10 Dia 7mm long case 10 Ohms. 2.8g The force of putting the prop on danages the motor brushes? In a crash this would bugger it up right good! ? With a FliteHook grey prop direct drive it does 4.5g thrust at 3.28v supply direct from the transformer. 185mA current, Stall current 316mA (158) 1mm shaft
MKO6 Dia 6mm x 11mm long case. 11 Ohms Orange KP gears, gears not very well meshed, Balnaced Grey prop from Flitehook = (4.7v = 5g and 188mA) 135mA at 2.25g thrust 3.28v direct supply. Same but French Carbon version of U80 = 3.5g thrust, 176mA and 2.89v. Same but std U80 balanced 4g thrust 187mA
Mk06 Dia 6mm x 11mm long case 12 Ohms direct drive using DIY plastic cup prop Dia 56mm x 5mm wide 3.3v = 230mA 1.5g thrust max. 4.7v = 2g thurst 350mA (stalled current = 400ma) Cut down prop to 50mm x 5mm wide 3.3v = 240mA 1g thrsut (4.75v = 1.75g thrust 340mA) weighs 2g complete
Nick Leichty's pager with Gasparin wood Co2 prop. 3.3v supply = 275mA and 4g static thrust , 4v supply = 350mA and 5.25g static thrust total weight about 2.75g, 4.5 Ohn dia 6mm pager 12mm long case
MK04S 13 Ohms, geared using didel 9t and 36t = 4:1. 3.28v = 100mA and 1.75g stall current 3.28v = 230mA (over geared) using grey flitehook prop. U80 std prop150mA 3g thrust (4.7v = 5.5g and 230mA)
MK04S 13 Ohms, 30 and 9 T didel. 3.333 : 1 gearing. Prop whizzes along so shoudl be better for slightly fast plane. 3.28v = 2.25g thrust 135mA. 4.7v = 3g thrust and 187mA Grey flitehook prop, poor meshing gears, brass tube bearing. direct to the transmormer.
MK04S 11.5 Ohms, 30 and 9 T didel. 3.333 : 1 gearing. Prop is slow reving. DIY plastic cup prop. Gears are well meshed. Tip angle 20 degrees, cut down in dia. to 78mm so it does not flex as much. 3.3v = 178mA and 2g thrust. Cut prop down to 67mm dia. 3.3v = 155mA 1.75g thrust faster reving now. Width of the blades cut down 1.6mm at the LE for the last 30 per cent of the blade 3.3v = 175mA (!) and 1.75g thurst (4.75v = 265mA and 2.5g thrust)
Blades cut down along lenght 67mm dia still 3.3v = 157mA and 1.75g thrust. Cut down to Dia 56 mm 3.3v = 145mA 1.75g thrust. Width of balde cut down to 5mm wide 3.3v = 130mA 1.5g thrust motor gears and prop now weigh 2g complete. (4.7v = 220mA 2.5g thrust) 3.28v = 2.25g thrust 135mA. 4.7v = 4g thrust and 187mA Grey flitehook prop, poor meshing gears, brass tube bearing. direct to the transmormer. 3.125g thrust at 3.99v
MK04S 13.2 Ohms, 30 and 9 T didel. 3.333 : 1 gearing. Prop is Flitehook grey plastic with tips twisted to 20degrees as Peter Frostic idea. 3.28v = 2.25g thrust 170mA. 4.7v = 3.25g thrust and 270mA Good meshing gears, brass tube bearing. 1mm s/s shaft, nylon thrust washer, direct to the transmormer. Balanced prop
Pager Manufacture unknow 1mm shaft Dia 6 x 15mm long 8 Ohms 3.28v supply from transformer does 295mA and 3.5g of thrust.
Iron Core mini motors
Potensky servo motor 7 Ohms Iron core approx 2.75g weight, stall current at 3.28v = 370mA , direct drive with grey Flitehook prop.3.28v = 260mA at 4g thrust 4.7v = 5.5g thrust and 370mA
Wes Tech / Falcon Models, 3 - 015, 1mm shaft, 4.2 Ohms. Stall current at 3.3v = 600mA
Weight = 2.4g,
Direct drive with U80, 3.3v = 6g thrust @ 480mA , 4.7v = 8g @ 700mA
Direct drive with Orange GWS balanced 3.3v = 6g @ 350mA 4.7v = 9.5g @ 525mA fast reving
Direct drive with Grey Flitehook prop. 3.3v = 370mA @ 5.5g 4.7v = 9g @ 550mA fast reving
Direct drive with small black Carbon fibre taperd prop and rough side facing forwards
3.3v = 5.5g @ 445mA, 4.7v = 8.5g @ 650mA
Peter Frostick suggests increasing the pitch of the grey plastic Potensky props from Flitehook.
This is done by gently warming the hub end of the prop blade with a soldering iron and twisting the blade with long nose plyers. Try and keep the blade 90 degrees to the prop shaft.
A simple jig can be used to check the angle of the blade tips. Push the prop onto a peice of steel wire and hold it vertical in a (brass) tube. Set the angle with a template. Balance every prop. even new standard ones. At our levels of power an out of balance prop makes a noticeable difference of thrust and vibration levels. Balance props on a pin, scrape off some plastic from the TE of the blade. Bernard and Mark some times enlarge the prop hole to make it easier to push the prop onto the motor, this force can be quiet high for a little plane
Easier to do than get into focus!
80 x 2 = 160 80 x 2.5 = 200 80 x 3 = 240 80 x 3.5 = 280
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