The Official Warp Mod Thread.

[cbmd]

Originally Posted by Luvmyhelis

… the stock boom is going away since mine is producing nasty harmonic resonant vibes that show up as tail vibes.

I tore down and rebuilt the tail three times. In this iteration I arrived at a point where the tail with blades mounted feels ok-ish up to 15K rpm, which corresponds to a head speed of 3125 rpm at a 4.8 head/tail ratio. Any more rpms and tail rod and fin start to vibrate. The margin between "no vibes" and "wouldn't fly with that" seems to be very narrow.

What I did to debug this so far:

• Spin up with only main shaft (no head) and main gear: vibe-free@100% throttle
• Add just the tail boom, no tail belt: still fine at 100%
• Add tail belt and tail shaft (verified to be straight): still fine at 100%

The first time around, the tail pulley was too tight between the plates and the plates were not parallel. Second time, it was better although not good enough yet. Third attempt with replacement parts and quite some effort yielded parallel plates and a tail pulley sized just right: no side-to-side play and not pushing on the inner bearing races.

• Add tail hub: still fine at 100%
• Adding the tail blade grips without blades: slight vibration starts at ~90%

With an unloaded motor, 100% throttle should give more rpm than the tail will ever have to cope with under normal flying cirumstances. So I put my tail grips, blades, chinese weights, screws &ct. on a scale and by mixing and matching parts I managed to get them statically balanced to within 0.01g.

As I said above, that leaves me with a current head speed limit of about 3125 vibe-free rpm, which seems a little low to me. Steps left: testing variations of tail belt tension and attempting dynamic balancing of the tail. Feels somewhat like grasping at straws, however. I'm not desperate enough to splurge money on a Skookum as a dedicated vibe analysis unit, yet.

In the days of tail struts, a tail resonance vibration sometimes could be fixed by connecting the struts or by changing the position of the boom clamps to shift the excitation frequency. How would I test if harmonic resonant vibrations of the tail boom cause my problem and what could I do eliminate them?

[Rob43]

The ingredients to resonance are mass and rigidity. You might find a sweet spot for rigidity in the boom with the tightness of the boom clamp. Even though you achieved static balance of the tail grips, they will cause excitations if the center of gravity of the grips are slightly different. I would think this could be evidence that they are not equidistant from the center of tail shaft. Several possible assignable causes for this...grips not seated fully in the outermost position - maybe a thrust bearing issue, or, perhaps a defect in one of the tail grips. Lastly, it could simply be the tail hub itself isn't symmetrical. You might want to consider hanging loose until the new boom is avaialable if you cannot track it through any of these issues. I most suspect the tail hub.

Just my thoughts from thinking through dynamic balance versus static balance.

[frito169]

Check your tail hub mine was bent.

[cbmd]

Thanks for the pointers. The two tail hubs I have are both perfectly on spec as far as I can measure them. The ends are equidistant from the shaft, on both the threads are both tapped to the same depth and when assembled with the tail grips, the screws head to head distance is the same as without the grips involved (indicates that outer bearings are properly seated.) Inner bearings are fully seated, too.

CoG of grips is a good point, I could try to swap just one with one of my other set. Increasing the tightness of the boom clamp is another good idea, I may have been too careful. Testing with really loose tail blades might be worth a shot, too. Although I assume that this would only come into play if they are really tightened down and ability to lead/lag on control input is involved. Lastly, if the vibration is induced at the tail, putting a small gel-like silicone pad on the upper part of the fin might help (changes mass and adds dampening). And yes, the .4mm walled new tail boom might also change the equation.

[Stevemech]

Maybe you could use the Protos boom until the thicker ones become avaiable in March?At least you could test the theory!
Steve

[weelee]

I had terrible vibes at 100% down to 90% then at 80% all was smooth. I loosened the tail belt first. Then i checked the tail hub. On the bench both grips moved smoothly but once on the heli one would move freely but the other was sticking. I thought this was stopping it from extending to the same distance as the other side. Cleaned it up and now i have almost no vibes up to 100% throttle.

[Kendo]

Originally Posted by weelee

I had terrible vibes at 100% down to 90% then at 80% all was smooth. I loosened the tail belt first. Then i checked the tail hub. On the bench both grips moved smoothly but once on the heli one would move freely but the other was sticking. I thought this was stopping it from extending to the same distance as the other side. Cleaned it up and now i have almost no vibes up to 100% throttle.

Cleaned up what how?

[weelee]

Cleaned the tail hub with a cloth added a small amount of thin oil, clean the bearings ID ring by threading a paper towel through them. Slid them on to the hub and moved them in and out to get the oil in there. Then screwed it back together. One thing, be very sparing with the thread lock. If any oozes out the end it causes a ridge that also stops the grip from moving out equal to the opposite side.

[cbmd]

Results from this day's bench-testing: Huge improvement. I can now run up with tail blades (no main blades) to 100% throttle with about as much vibration as I had before at 70%. I wish there was a better way to quantify that. At about 92% a metallic whining starts to creep in. Does not sound too bad, but not sure yet where it originates from, might be the tail shaft bearings. 100% gives me 15.200 rpm on the tail.

I settled on a medium tail belt tension, as it did not seem to have much influence on the vibe level. What did the trick was running the motor belt quite loose and increasing the tail boom clamp pressure quite a bit, now there is a 0.5mm gap still left between the clamp blocks. It seems that my remaining vibrations are actually induced by the motor.

[Luvmyhelis]

Originally Posted by cbmd

It seems that my remaining vibrations are actually induced by the motor.

exactly as I found earlier. And I double checked my motor balance today. Spot dead on.

[Luvmyhelis]

Also, I wanted to add something more to this thread.

I just pulled off the SDPI 12T pinion install and got it fully seated in today.

The 12T gear can either be used on any stock 3.17 shafted 450 motor or preferably the Scorp 2200 6s cans such as the 1630kv. It also worked perfectly on my newer Scorp 1360kv motor. Since all Scorpion 450 motors are a 4mm shaft inside the motor and neck down to a 3.17. The length of the 4mm shaft that engages the motor bearings is the same width in the new 1360kv version also. So by introducing one of the necked down main motor shafts into the 1360kv version, the 12T 3.17mm shaft gear now fits.

If you are doing the latter you will need a stock Scorp 3.17 2200 can motor shaft. And installing it in the motor is a cakewalk. Again, the shaft fits perfectly as it has a 4mm thick diameter inside the motor itself and will fit either motor before necking down into its 3.17 drive diameter.

The biggest pia here is getting the 12T gear as shipping rates rape you from SDPI if you are only ordering just one part. So before you do. Post up here in the Warp section and ask others if they want to group buy with you. Or ask if anyone else is ordering. Helihaven probably orders from them monthly. So pm him also.

The very first thing you will want to do is remove the tension roller assembly from your heli and remove the lower motor support shaft flanged bearing out of it. Mainly since the lower edge of the new 12T pinion will contact the flanged area if you don't. It is that close. I just briefly hit it with a butane fireplace starter on the mount around the bearing, and the bearing popped right out with little effort.

Next, take the new gear and remove roughly 3/16 off the bottom of it. The best reference I could say is to remove enough off the bottom of it so the angle cut on the bottom before the very bottom flat is all gone where it could contact the motor plate. This will give you enough room so that it moves in close enough to the mounting plate to give perfect belt alignment. If you look at the pic you will see I left it with some angle at the bottom and not perfectly flat. I still wanted the gear to have as much engagement on the insert they use inside it as possible.

Now, either break out a dremel, porting tool, or a round hand file and oval out the main motor shaft hole in the motor mount plate itself. What you want to do here is to cut it at an angle so the motor moves over towards the back left, away from the larger tension roller on the right hand side of the lower tension roller plate. Remove 3.5mm of material or enough that the motor will slide all the way over so the remaining virgin slot stops the outer motor bolt.

What I mean by this is to use the two motor mount holes that are farthest apart. As the two closer ones will allow the bolts to contact the 12T gear when you try and install it. By the time you cut 3.5mm out and elongate the main motor plate hole this L/R side of the plate will turn into one large oval right into the bolt slot. The thin area between the slot and main hole will be gone. Make absolutely sure you have enough room when the motor is pushed all the way over so the motor retaining clip on the motor shaft still clears the plate all the way around the shaft. And the forward right bolt hits the stop at the inside slot.

On both the Scorp motors, the 2200 can 450 version and the larger 1360kv. The motor wires will now be exiting out the right side of the motor where there is now room by the frame to route them forward if needed. Since the motor itself will be setting off to the left and back farther as you can see in the pics. The reason I cut the slot in the plate is to keep the actual motor mount plate holes in the carbonfibre body panels exactly the same! This mod requires no lengthening of those body slots to work properly.

If you don't slot the motor plate, these holes in the frame will need to be cut back almost a full 5mm, and the back ones are dangerously close to cutting through the upper frame area! You also loose some needed angularity of the motor tension roller in relationship to the pinion. So the belt isn't as secure around the 12T.

Now, take the modified 12T gear and lightly install it after the motor plate has been installed on the motor. (Again, slide the motor all the way to the left and back until the motor mount bolt hits the one remaining upper RH stop) and push the pinion down almost until it contacts the plate. All you need here is a 16th of an inch or so. Then contact tighten the grub screw on the 12T into place. This will be just snug. But not tight enough to seat it. Rock the main motor can back and forth while the .50mm allen driver holds the gear from rocking as it is still seated inside the grub screw. The movement of the gear against the main shaft will score it. This way you will know exactly where to dremel the cut in the shaft in a moment to anchor the gear! No guessing. And the cut doesn't need to be large. Just half a mil deep at most and 2mm wide. This will allow the grub screw to seat perfectly!

Now reinstall the tension roller assembly and motor. When you tip the Warp on its side to check the main belt you will see the belt is tracking right down dead center of the main, 12T and tension pulley.

So now you either have a 3.17mm shafted 6s 1630kv 450 motor installed into your Warp 360 with closer correct gearing. Or, you will like me have the new Scorp 1360kv motor with a 12T gear so you can run a stretch. On mine I will be running my favorite MsComposite 420s, and this mod limits head speeds to 2400 with this motor. Which is perfect!

https://www.helifreak.com/showthread...=493476&page=3 post 24.

[cbmd]

Originally Posted by Luvmyhelis

exactly as I found earlier. And I double checked my motor balance today. Spot dead on.

The Compass motor all by itself or when mounted on the plate (with or w/o pinion) seems to be balanced ok and runs without noticable vibes. The motor shaft is straight and true as far as i can measure and the counter bearing is aligned properly My working theory is that once the side-load from the belt comes into play, tolerances add up and the bearings become unhappy at moderate to high speed, creating a resonance.

I have no idea when Compass and/or the German distributor will ship the new motor can and still await warranty replacements of three faulty parts from my v1-kit, those are pending since Dec. 12, 2012. So I'd rather not hold my breath while waiting and instead go directly to the Scorpion HK-2520-1360Kv. I'd have to pull the Compass motor either way.

[lcc014]

Originally Posted by Luvmyhelis

Also, I wanted to add something more to this thread.

I just pulled off the SDPI 12T pinion install and got it fully seated in today.

The 12T gear can either be used on any stock 3.17 shafted 450 motor or preferably the Scorp 2200 6s cans such as the 1630kv. It also worked perfectly on my newer Scorp 1360kv motor. Since all Scorpion 450 motors are a 4mm shaft inside the motor and neck down to a 3.17. The length of the 4mm shaft that engages the motor bearings is the same width in the new 1360kv version also. So by introducing one of the necked down main motor shafts into the 1360kv version, the 12T 3.17mm shaft gear now fits.

If you are doing the latter you will need a stock Scorp 3.17 2200 can motor shaft. And installing it in the motor is a cakewalk. Again, the shaft fits perfectly as it has a 4mm thick diameter inside the motor itself and will fit either motor before necking down into its 3.17 drive diameter.

The biggest pia here is getting the 12T gear as shipping rates rape you from SDPI if you are only ordering just one part. So before you do. Post up here in the Warp section and ask others if they want to group buy with you. Or ask if anyone else is ordering. Helihaven probably orders from them monthly. So pm him also.

The very first thing you will want to do is remove the tension roller assembly from your heli and remove the lower motor support shaft flanged bearing out of it. Mainly since the lower edge of the new 12T pinion will contact the flanged area if you don't. It is that close. I just briefly hit it with a butane fireplace starter on the mount around the bearing, and the bearing popped right out with little effort.

Next, take the new gear and remove roughly 3/16 off the bottom of it. The best reference I could say is to remove enough off the bottom of it so the angle cut on the bottom before the very bottom flat is all gone where it could contact the motor plate. This will give you enough room so that it moves in close enough to the mounting plate to give perfect belt alignment. If you look at the pic you will see I left it with some angle at the bottom and not perfectly flat. I still wanted the gear to have as much engagement on the insert they use inside it as possible.

Now, either break out a dremel, porting tool, or a round hand file and oval out the main motor shaft hole in the motor mount plate itself. What you want to do here is to cut it at an angle so the motor moves over towards the back left, away from the larger tension roller on the right hand side of the lower tension roller plate. Remove 3.5mm of material or enough that the motor will slide all the way over so the remaining virgin slot stops the outer motor bolt.

What I mean by this is to use the two motor mount holes that are farthest apart. As the two closer ones will allow the bolts to contact the 12T gear when you try and install it. By the time you cut 3.5mm out and elongate the main motor plate hole this L/R side of the plate will turn into one large oval right into the bolt slot. The thin area between the slot and main hole will be gone. Make absolutely sure you have enough room when the motor is pushed all the way over so the motor retaining clip on the motor shaft still clears the plate all the way around the shaft. And the forward right bolt hits the stop at the inside slot.

On both the Scorp motors, the 2200 can 450 version and the larger 1360kv. The motor wires will now be exiting out the right side of the motor where there is now room by the frame to route them forward if needed. Since the motor itself will be setting off to the left and back farther as you can see in the pics. The reason I cut the slot in the plate is to keep the actual motor mount plate holes in the carbonfibre body panels exactly the same! This mod requires no lengthening of those body slots to work properly.

If you don't slot the motor plate, these holes in the frame will need to be cut back almost a full 5mm, and the back ones are dangerously close to cutting through the upper frame area! You also loose some needed angularity of the motor tension roller in relationship to the pinion. So the belt isn't as secure around the 12T.

Now, take the modified 12T gear and lightly install it after the motor plate has been installed on the motor. (Again, slide the motor all the way to the left and back until the motor mount bolt hits the one remaining upper RH stop) and push the pinion down almost until it contacts the plate. All you need here is a 16th of an inch or so. Then contact tighten the grub screw on the 12T into place. This will be just snug. But not tight enough to seat it. Rock the main motor can back and forth while the .50mm allen driver holds the gear from rocking as it is still seated inside the grub screw. The movement of the gear against the main shaft will score it. This way you will know exactly where to dremel the cut in the shaft in a moment to anchor the gear! No guessing. And the cut doesn't need to be large. Just half a mil deep at most and 2mm wide. This will allow the grub screw to seat perfectly!

Now reinstall the tension roller assembly and motor. When you tip the Warp on its side to check the main belt you will see the belt is tracking right down dead center of the main, 12T and tension pulley.

So now you either have a 3.17mm shafted 6s 1630kv 450 motor installed into your Warp 360 with closer correct gearing. Or, you will like me have the new Scorp 1360kv motor with a 12T gear so you can run a stretch. On mine I will be running my favorite MsComposite 420s, and this mod limits head speeds to 2400 with this motor. Which is perfect!

https://www.helifreak.com/showthread...=493476&page=3 post 24.

Great detail instruction with pictures. Many thanks.

[Stevemech]

Randy, it looks like you had to take alot of metal away on the motor mount,it looks alittle weak ,could just be the camera angle though?
Steve

[Luvmyhelis]

Originally Posted by Stevemech

Randy, it looks like you had to take alot of metal away on the motor mount,it looks alittle weak ,could just be the camera angle though?
Steve

The bridges left in the plate should be more than adequate. Although I carved out 2.5mm more than I instructed as needed on this on mine.