Servo saver mod

[Nelsonisms]

Is that Napa like the auto part stores? I tried Googling that part number and came up with nothing.

However, I did learn that the binary representation of 407004 is 1100011010111011100.

[Hydros27]

I had no luck searching that number either. I just measured some o rings when I saw the post. That is the part number of an air conditioning o ring NAPA Auto Parts stocks for us at work. The number on the package is: 407004/A37069. There is no brand name on the package. Our NAPA salesman uses the first half of that part number when he restocks the cabinet so they should be able to help you at a NAPA store. Hope that helps.

[Go for it]

Originally Posted by Hydros27

I had no luck searching that number either. I just measured some o rings when I saw the post. That is the part number of an air conditioning o ring NAPA Auto Parts stocks for us at work. The number on the package is: 407004/A37069. There is no brand name on the package. Our NAPA salesman uses the first half of that part number when he restocks the cabinet so they should be able to help you at a NAPA store. Hope that helps.

I found some red silicone o rings at Oringsandmore. They are the same as the ones we use on the ball links, just bigger.
After mesuring the horns(sorry for the ASA measures but Oringsandmore is an American company) I got:

Horns foot = 7/32

So to be on the safe side( they are only 3.25 for 100) I ordered 3 sizes.

# 08 = 3/16'' or 1/32'' smaller then the horn foot
# 07 = 5/32'' or 1/16" smaller
# 06 = 1/8" or 3/32" smaller

I'll let you know which one I feel is the best. If some of you can't get them I can send you some for the price of postage. We'll see when I get them.

[Nelsonisms]

I found the links for those. Here they are for reference...

# 08 = 3/16'' or 1/32'' smaller then the horn foot
# 07 = 5/32'' or 1/16" smaller
# 06 = 1/8" or 3/32" smaller

I think you're right that one of those should work perfectly. And you'll have 297 o-rings to spare.

[JohnTC02]

Just done this mod to my 150, put 8 flights on it and all is fine without any o-rings fitted. To me the horns are quite stiff to turn over the splines so I'm not convinced the o-rings are needed.

Having said that I'm only sport flying but I still think it would be ok for 3d.

[gabeoravitz]

Originally Posted by JohnTC02

Just done this mod to my 150, put 8 flights on it and all is fine without any o-rings fitted. To me the horns are quite stiff to turn over the splines so I'm not convinced the o-rings are needed.

Having said that I'm only sport flying but I still think it would be ok for 3d.

That's great. It's possible they'll loosen over time though.

[gabeoravitz]

Originally Posted by mdecker79

What plugs are you using for your servos? Did they fall apart and you put on new connectors? The wires are different colors then the stock plugs.

Yep. I pulled the plugs out and the wires ripped out like they were made of paper. They are entirely too fragile. At least on my first batch 150. I would like to think they've been improved by now.

[_Kyle_]

Originally Posted by gabeoravitz

Yep. I pulled the plugs out and the wires ripped out like they were made of paper. They are entirely too fragile. At least on my first batch 150. I would like to think they've been improved by now.

When you take them out be careful because this can happen.. I use a Small Flathead Screwdriver and pop them out.. Won't hurt the wires or even touch them.:thumbup

https://www.helifreak.com/attachment...2&d=1392224049

[SP4772]

I saw that picture somewhere.... I feel that the entire heli is quite small and fragile. U can't just work on it without a good light and quality tools. Changing servo gears will be a surgeon operation!

[gabeoravitz]

Originally Posted by SP4772

I saw that picture somewhere.... I feel that the entire heli is quite small and fragile. U can't just work on it without a good light and quality tools. Changing servo gears will be a surgeon operation!

It's actually pretty easy, I thought.

[Zareph]

Would this be applicable to a V911, or is it too light-weight or something?

Cheers,
- Zareph

[Miracle Boy]

Originally Posted by Dipweed

I got 5.1mm OD plastic is just not that dimensionaly stable. It maybe by design 5mm+ 0.5 mm?
Using plastic caliper 3 measures. Mic may give a better reading (don't have).

5.1mm interesting. I measured around the collar at either side of the width of the servo horn. Did you measure across the collar in line with the length of the horn?

Cheers!!

[gabeoravitz]

Originally Posted by Zareph

Would this be applicable to a V911, or is it too light-weight or something?

Cheers,
- Zareph

Any heli that has rotary servos, this can apply. If the V911 strips servos in crashes, it's worth a try. I'm not sure if the lower head speed of a small FP heli is going to have that problem or not. I've never had a V911 so I can't say.

[Nelsonisms]

So I scoured my LHS high and low on the "dark side" (rc cars) and couldn't find any o-rings anywhere close to this size. Home Depot was a no go. Same with Lowes. So I'm tapped out with finding a local source. I did however find some little sealing o-rings on a couple of my spent e-cig cartomizers that I'm going to try. If those don't work out I guess I'll order some from ORingsAndMore. @Go For It: Definitely let us know which ones worked out the best once you give them a try. Anyways I'm still waiting on the heli since the old postman is taking his sweet time.

[gabeoravitz]

Originally Posted by Nelsonisms

So I scoured my LHS high and low on the "dark side" (rc cars) and couldn't find any o-rings anywhere close to this size. Home Depot was a no go. Same with Lowes. So I'm tapped out with finding a local source. I did however find some little sealing o-rings on a couple of my spent e-cig cartomizers that I'm going to try. If those don't work out I guess I'll order some from ORingsAndMore. @Go For It: Definitely let us know which ones worked out the best once you give them a try. Anyways I'm still waiting on the heli since the old postman is taking his sweet time.

I believe this is what mine are (I found them in a box of random stuff). I used to have this heli. I sliced these in half to make them thinner.

http://www.bladehelis.com/Products/D...ProdID=BLH1608

[Nelsonisms]

Originally Posted by gabeoravitz

I believe this is what mine are (I found them in a box of random stuff). I used to have this heli. I sliced these in half to make them thinner.

http://www.bladehelis.com/Products/D...ProdID=BLH1608

Hmm...it just so happens I might have some stock 450X dampeners laying around. I use Lynx ultra dampeners in mine so the stockers are unused. I'll give that a shot too. Thanks.

[DPW]

Truth
I don't like splitting the servo arm
but
Servo Horn Set HSP15003 $4.99
Its a low $ deal so I will get a set and split the arm.
I will use a single edge razor blade (thinner the better). Externally glue the split arm together (flexible glue).
O ring stuff
O ring is a little to much and seems like a split arm should have a O ring grove or glue the O ring in place.
Question?
Has anyone flown with only the split servo arm?.

[Nelsonisms]

It seems to me that gluing with a pliable glue would work great until that first crash. If the glue broke free you'd then be putting glue on top of glue. As long as the o-rings are small and just tight enough to apply a little pressure I doubt they would slip around too much and would be easy to re-seat in the event of a crash that tweaked the arm on the spline.

JohnTC02 reported in post #25 that he had done it without o-rings and it worked fine for him. The thought here is that they may loosen up over time, so the o-rings are to keep a constant tension over time.

[kimthepilot]

I drilled some holes in my servo arms, in an effort to weaken them just enough to break in a crash. You get 6 servo arms for the price of one set of servo gears, so hopefully this works!

[gabeoravitz]

Originally Posted by Dipweed

Truth
I don't like splitting the servo arm
but
Servo Horn Set HSP15003 $4.99
Its a low $ deal so I will get a set and split the arm.
I will use a single edge razor blade (thinner the better). Externally glue the split arm together (flexible glue).
Question?
Have you split the arm and flown it with out the O ring stuff. O ring is a little to much and seems like a split arm should have a O ring grove or glue the O ring in place.
Again
Has anyone flown with only the split servo arm?.

I have flown it without the o-rings. It works. It's just really lose and it got to the point that when I started doing hard 3D, it would slip in flight. It doesn't cause a crash automatically as long as you are quick enough to make up for the lost of pitch in either direction. The FBL system still keeps it stable, it just if it slips in flight, it needs more pitch in one direction or another on the stick.

I like the idea of a flexible glue on the split though.