duragg Posted July 8, 2012 Share Posted July 8, 2012 Playing with Android apps today and found this cool vibration analyzer: Vibration analyzer Also found this neat spread sheet to calculate various frequencies: Spectrum estimator WARNING: download this spreadsheet at your own risk, it gave me no problems. Ever since I rebuilt me engine, tranny, diffy, etc I have had annoying vibration probably related to the Solid front diff mount and driveshaft or Halfy imbalance. Just for fun I am going to see if I can isolate the vibration frequency. Should be able to see a peak before or after the final drive ratio. Just a fun toy for a stinking hot sunday in Phoenix. Tj Quote Link to comment Share on other sites More sharing options...
duragg Posted July 9, 2012 Author Share Posted July 9, 2012 I used the Spectrum estimator to calculate for my Frontier and indeed the Vibration Analyzer correctly pinpointed my out of round tires on the truck with a big spike right at 13hz at 70mph as expected. But in the Z it was too hard to find a good place to pickup the vibrations and I think the vibes I have are too high frequency for the accelerometer in the HTC Thunderbolt. Looks like it only goes up to around 30Hz and +/- 2g. I wasn't able to go fast enough to get a pronounced vibration without exceeding the range of the device. Some other smart phones might have up to 100HZ in the accelerometer. Still a handy doo-hickie Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 21, 2012 Share Posted July 21, 2012 Android... argh... Now I got to buy an Android Tablet or something so I have this back. I worked with 'reed boxes' for years and this sounds as accurate as those were. You're dead nuts correct: a few calculations and you can know EXACTLY where to look! REALLY want to say thanks for this little tidbit. Now, to see if I can justify it for work so I don't have to pay! How cheap is THAT!?!?!?... Quote Link to comment Share on other sites More sharing options...
duragg Posted July 21, 2012 Author Share Posted July 21, 2012 The limitation is the Hz range of only 32Hz on my device although the HTC docs say 100Hz. Not sure if it is software or hardware. I was flying a Mooney with a bad vibration recently and used this App. It identified a peak at 20.25Hz which is half crankshaft speed. Unfortunately the 1x crank was off the scale. It also has no data logging. It also is free. Let me know what you find. There may be an iPhone comparable? Quote Link to comment Share on other sites More sharing options...
duragg Posted July 24, 2012 Author Share Posted July 24, 2012 Ever since I put in the 4.375 R200 with the solid front diff mount I have had a wicked vibration, starts around 45mph and by 85mph it is just plain scary. Increasing in a linear fashion. I finally got my R/T mount with Energy bushing and will install in place of the (hideous) billet aluminum mount. Taking driveshaft to the shop for balance and new u-joints. Ya, I could do it myself, but for $100 bucks I think I will let a Pro have the pleasure. Quote Link to comment Share on other sites More sharing options...
duragg Posted July 24, 2012 Author Share Posted July 24, 2012 Driveshaft shop said my Driveshaft was "wasted" and the caps and joints just fell out once the clips were removed. There was material worn out from the inner race where the cap should be pressed in so the bearing cannot do its job if the cap is spinning. They offered to just make me a brand-new D/S with standard Spicer joints for $175 bucks so I just went for that. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.