|Topic Review (Newest First)|
|01-02-2020 03:57 PM|
|Broaner||Bingo. That was pretty much the exact verbatim summary of last time we tried to go through that process. I appreciate your effort on the topic though.|
|12-30-2019 06:20 PM|
Well I am finally going to abandon building high quality gearing. Talking with the engineer again about my plan it has a few flaws. The gear design itself is ok at best for a low torque application. Making the OD gear out of high quality material helps but not enough. He went through some calculations with me this morning on tooth strength and there isn’t a material that exists that would be strong enough to handle 1000+ lbft of torque for any period of time deemed ok. On a side note he compared the Eaton FSO-8406a to the NV5600 OD gear only. And the Eaton appears to be over 8 times stronger. This is due to the gear just being much larger. As small as the nv5600 gear is slight increases in size drastically increase strength.
Next one might ask why not make the nv gears bigger. Well this would be very costly due to the center distances of the shafts in relation to each other these would have to change which requires case changes and all other gears to change. Can it be done yes, but not with my pocket book.
So to steelhead he was right in it being in adequately designed especially for a diesel. Guess that’s why Chrysler abandoned it. I clearly had to high expectations for what a high quality material would do. It would help but not enough.
|12-04-2019 09:34 AM|
Originally Posted by justin time View Post
|12-03-2019 05:18 PM|
My plan (at least in my head) was to reverse engineer and have a cad file using faro technologies.
Wouldn't a multi axis cnc machine be able to make that happen?
|12-01-2019 08:47 PM|
|NCA||Yes a high quality material would last longer. However given the way the gear is shaped it couldn’t be billet. It would have to be two pieces. There just isn’t room to cut the teeth and have the plate part of the gear through the machining process. As to a spiral gear I don’t know what your talking about.|
|11-29-2019 05:41 PM|
Do you or the engineer your working with think just a plane billet gear would hold up better than stock? The reason I'm asking because I've heard it wouldn't.
Can you explain this spiral gear a little more your talking about?
|11-27-2019 10:21 PM|
I broke tranny #7 (I think lost count by now) twisted the plate right of the gear about 2800 miles, 4-5% grade, 22k gross about 50ish lbs boost @ 78 mph. Second or third time this has happened. Running for now without OD.
I sat down with the engineer last week. To see where things were at. The plate is a weak link he calculated at best may hold 1100-1500 Ftlbs torque with a marginal safety factor (hardly any). By splining the plate on it would drastically increase strength. So hopefully he’s not too far off from getting it engineered. I guess that why the factory design was for 400ftlbs of input torque on this gear. (550x.73= 401.5).
Other things that must be considered by making this gear stronger
1 will the pocket bearing be able to handle the increased radial load from the shafts trying to push apart?
2. Is the end of the main shaft (where the pocket bearing goes) going to hold up to the increased power?
3. If the answer is no on either of these the inside pocket on the main shaft must be made larger. To do this requires a larger input gear and smaller countershaft drive gear. This would make every gear a higher drive ratio (except 5th that’s direct).
4. Do I want to spend 3-4K just for two gears (6th mainshaft and 6th countershaft) when I am not sure the rest of the components will hold up? Not really
5 Why does a 48 overdrive seem to hold up? It is a 6 pinion planetary. The helix angle is 15 degrees, just guessing that’s about 1.5 tooth contact per pinion times 6 pinions makes 9 teeth in constant mesh. The ring gear contains everything so it is all balanced and not side loading any shafts. The nv5600 helix angle is much steeper and is 1.8 teeth in constant mesh. Also the reason the heavy truck transmissions have 2 countershafts. The the main shaft is in a neutral plane not forced to either side.
With that said I will be making a decision on what I am going to do depending on cost of high quality gearing.
|11-22-2019 06:14 PM|
|justin time||All of the info that I've researched says no, have to buy new gears.|
|11-19-2019 04:45 PM|
|Rx7man||Is there any source for early NV5600 synchros and parts yet?|
|11-19-2019 04:09 PM|
|Broaner||I don't know where to get the good stuff but I do know AT is absolute dog feces. Don't touch it with somebody elses 10' pole|
|11-16-2019 01:48 AM|
|Wombat Ranger||Manufacturer's ID stamps|
|11-14-2019 02:00 PM|
Originally Posted by Wombat Ranger View Post
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