Nelson drive washer
08-19-2003, 10:22 PM
#1
Senior Member
Thread Starter
My Feedback: (9)
Join Date: Jan 2002
Location: Indianapolis,
IN
Posts: 1,752
Likes: 0
Received 0 Likes
on
0 Posts
Nelson drive washer
I have been flying the CAPS standard class this year and have every intention of flying 428 next season. I recently bought a used Nelson to get used to. I didn't get any info with it so I'm not sure how to "clock" the drive washer so that the balance slot is in the right place. I heard a few discussing it at the CAPS Classic but didn't pay much attention then since I didn't have a Nelson at the time. How do I do it per the instructions that come with the engine and is there a preferred method?
Thanks,,,basmntdweller
Thanks,,,basmntdweller
08-20-2003, 01:13 AM
#2
Senior Member
My Feedback: (5)
Drive Hub Slot
B, here's what I do,,,
I remove the plug which makes it easy to turn the crank. I then remove the backplate and center up the crank hole with the crank case hole. Now, center the "slot" at the 12 o'clock position or inline with the carb hole. Very carefully now tighten down the prop at the 6 & 12 o'clock position,,, install backplate and plug.
Add a few drops of after run oil to loosen up the engine. Prop it a few times,,, where the props stops due to the up swing on the compression stroke,,, make a mark on the case where the slot is! This will be your "reference mark" for future prop changes and the counter balance drive hub setting.
With the engine mounted on the side,,, the prop will stop at the 3 & 9 o'clock position when the engine is shut off
BV
I remove the plug which makes it easy to turn the crank. I then remove the backplate and center up the crank hole with the crank case hole. Now, center the "slot" at the 12 o'clock position or inline with the carb hole. Very carefully now tighten down the prop at the 6 & 12 o'clock position,,, install backplate and plug.
Add a few drops of after run oil to loosen up the engine. Prop it a few times,,, where the props stops due to the up swing on the compression stroke,,, make a mark on the case where the slot is! This will be your "reference mark" for future prop changes and the counter balance drive hub setting.
With the engine mounted on the side,,, the prop will stop at the 3 & 9 o'clock position when the engine is shut off
BV
08-20-2003, 01:41 AM
#3
My Feedback: (1)
Join Date: Dec 2001
Location: Waseca,
MN
Posts: 8,456
Likes: 0
Received 0 Likes
on
0 Posts
Nelson drive washer
Bill and I get the same result, but I do it a little different.
As Bill does, its easiest if you set it with the plug OUT.
1. Make sure you are at TDC.
2. When you are sure you are at top dead center, put the balanced thrust washer on the Crank with the notch at exactly 10 o'clock (to the head). Which means when you look at it from head on its actually at about 7-8 o'clock.
3. Hold the washer in place (with the head at TDC), and install the prop horizontal to the ground. I actually over rotate the prop a hair to about 8 and 2 oclock from the front.
4. tighten the prop to the washer holding everything in place. After it is tight, turn the prop over a couple times with the plug OUT to make sure your alignments are corrrect. Theres a little room for slop here, but not much.
If you are ever out of balance, your holder should be able to tell, because the plane will vibrate. If this happens shut down immediately, as this is very bad for receiver crystals and servos.
Hope to see you Rockford. I'll be there with a green plane or two.
As Bill does, its easiest if you set it with the plug OUT.
1. Make sure you are at TDC.
2. When you are sure you are at top dead center, put the balanced thrust washer on the Crank with the notch at exactly 10 o'clock (to the head). Which means when you look at it from head on its actually at about 7-8 o'clock.
3. Hold the washer in place (with the head at TDC), and install the prop horizontal to the ground. I actually over rotate the prop a hair to about 8 and 2 oclock from the front.
4. tighten the prop to the washer holding everything in place. After it is tight, turn the prop over a couple times with the plug OUT to make sure your alignments are corrrect. Theres a little room for slop here, but not much.
If you are ever out of balance, your holder should be able to tell, because the plane will vibrate. If this happens shut down immediately, as this is very bad for receiver crystals and servos.
Hope to see you Rockford. I'll be there with a green plane or two.
08-20-2003, 02:15 AM
#4
Senior Member
Thread Starter
My Feedback: (9)
Join Date: Jan 2002
Location: Indianapolis,
IN
Posts: 1,752
Likes: 0
Received 0 Likes
on
0 Posts
Nelson drive washer
Thanks guys, I'm going to fly tomorrow for the first time with the nelson.
Unfortunately, I don't think I will get to go to Rockford. My wife finally made up her mind when she wanted to go on vacation and that race weekend falls on the end of our vacation week. If I thought there was any way to fit that in to the vacation I'd try like hell. I got nasty looks last year when I brought one of my helis to fly off the water. A full race weekend would not go over well as a finish to our vacation! I thought it might work out since her brother and sister-in-law live just up the road in Beloit but she want to go south to Lake Cumberland in KY.
Maybe next time,,,basmntdweller
Unfortunately, I don't think I will get to go to Rockford. My wife finally made up her mind when she wanted to go on vacation and that race weekend falls on the end of our vacation week. If I thought there was any way to fit that in to the vacation I'd try like hell. I got nasty looks last year when I brought one of my helis to fly off the water. A full race weekend would not go over well as a finish to our vacation! I thought it might work out since her brother and sister-in-law live just up the road in Beloit but she want to go south to Lake Cumberland in KY.
Maybe next time,,,basmntdweller
08-20-2003, 10:46 AM
#5
Senior Member
Join Date: Dec 2001
Location: Brantford, ON, CANADA
Posts: 3,305
Likes: 0
Received 0 Likes
on
0 Posts
Nelson drive washer
This is the easiest way to set the balanced drive washer on both the Q500 and the Q40 engines. You do not have to take the plug out or force the piston to TDC.
Slip the drive washer on, turn the crankshaft (Anticlockwise) by hand until it bumps against compression. Align the slot halfway between the beam mounting lug and the venturi. That is it.
I will now let you all into a real secret that is even easier than the above. This applies to both Q500 and Q40. Make a mark on the FRONT of the drive washer, (In line with the slot of course). Make a mark on the crankshaft in line with the centre of the window. When putting on the prop driver just align the two marks.
You heard it here first!!
Ed S
Slip the drive washer on, turn the crankshaft (Anticlockwise) by hand until it bumps against compression. Align the slot halfway between the beam mounting lug and the venturi. That is it.
I will now let you all into a real secret that is even easier than the above. This applies to both Q500 and Q40. Make a mark on the FRONT of the drive washer, (In line with the slot of course). Make a mark on the crankshaft in line with the centre of the window. When putting on the prop driver just align the two marks.
You heard it here first!!
Ed S
08-20-2003, 04:00 PM
#6
Senior Member
My Feedback: (7)
He said it!
Whoa, Ed's modifying his cranks! No wonder he's so fast!
For QM40, I always plan my paint scheme so there's a visible spot (for example, the point where two stripes converge) just behind the spinner backplate, exactly on the top centerline of the fuselage. This provides a handy reference point for alignment of the counterbalanced spinner.
First, I align the spinner backplate with the crankshaft using the peer-down-the-venturi method described in gory detail by Dave, Ed, et al., above, and tighten the prop nut to hold it there. (Propeller alignment isn't important yet.)
When I'm satisfied that the spinner is correctly aligned on the crankshaft, I turn the spinner & prop (with glow plug removed) until the piston is at TDC. Note that when the piston is at TDC, it's possible to "click" the crankshaft back and forth a degree or two because of the play in the connecting rod.
Using the paint stripe as a reference point, I scribe two little marks in the edge of the spinner backplate, about 1/8" apart. One or the other of these scribe marks will line up with the paint stripe at TDC, depending on whether I "click" one way or the other. When I can "click" back and forth and they both align, I know it's exactly right.
The spinner backplate locks on to the crankshaft pretty well, so when I change props I usually don't have to realign it. But if I do, I know all I have to do is remove the glow plug, find TDC, line up the little marks with the paint stripe, and tighten the prop nut. After that I hold the backplate steady, loosen the prop nut just enough to free up the prop, and position the prop blades at about 1:00 and 7:00 clock positions when viewed from the front. This way it will always stop with the blades horizontal for landing.
Yes, Ed, I am modifying my spinner backplates. That's why I'm so fast!
For QM40, I always plan my paint scheme so there's a visible spot (for example, the point where two stripes converge) just behind the spinner backplate, exactly on the top centerline of the fuselage. This provides a handy reference point for alignment of the counterbalanced spinner.
First, I align the spinner backplate with the crankshaft using the peer-down-the-venturi method described in gory detail by Dave, Ed, et al., above, and tighten the prop nut to hold it there. (Propeller alignment isn't important yet.)
When I'm satisfied that the spinner is correctly aligned on the crankshaft, I turn the spinner & prop (with glow plug removed) until the piston is at TDC. Note that when the piston is at TDC, it's possible to "click" the crankshaft back and forth a degree or two because of the play in the connecting rod.
Using the paint stripe as a reference point, I scribe two little marks in the edge of the spinner backplate, about 1/8" apart. One or the other of these scribe marks will line up with the paint stripe at TDC, depending on whether I "click" one way or the other. When I can "click" back and forth and they both align, I know it's exactly right.
The spinner backplate locks on to the crankshaft pretty well, so when I change props I usually don't have to realign it. But if I do, I know all I have to do is remove the glow plug, find TDC, line up the little marks with the paint stripe, and tighten the prop nut. After that I hold the backplate steady, loosen the prop nut just enough to free up the prop, and position the prop blades at about 1:00 and 7:00 clock positions when viewed from the front. This way it will always stop with the blades horizontal for landing.
Yes, Ed, I am modifying my spinner backplates. That's why I'm so fast!
