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Must watch video hd gear mod

It really is that simple. Dry assembled to check meshing and I found make the bearing pack the same thickness as the housing depth do not install a shim before the first bearing (unless you took off too much material) install shims in-between spacers or 3rd bearing only to the depth of the housing... the remainder of space between the last bearing and the retaining clip groove needs to be shimmed to eliminate pinion play. Then protect with a Pro Mod Steve boot !
 
I just did what BHB did BUT one tooth at a time as I did not have his killer set up with the drill and it works great. Really youdon't need his set up as once I did 2 pinions I have been trouble free for months and as good as the gears look plan to be trouble free for months to come.
 
Thanks for the update but YOU have my pinions. Are you going to forward them to Castle Rock Machine or are you going to send both the pinions and personal check back directly to me? I would prefer the latter. Please advise ASAP.

Chuck Schipper
 
Thanks for the update but YOU have my pinions. Are you going to forward them to Castle Rock Machine or are you going to send both the pinions and personal check back directly to me? I would prefer the latter. Please advise ASAP.

Chuck Schipper

Hey Chuck ill make sure they are sent today "thumbsup I'll be returning the check as well because of the delay.
 
Cool your on youtube just saw your videos other night, David Downs is my youtube i got yeti xl and accidently had signal lost and ran into pond 8ft deep and was submerged 24hrs whoopie not bad for two days lol never done this in my 10yrs of messing with them
 
Hey guys I'll be testing out this BHB PINION BUSHING CONCEPT.
It's a oilite bushing that's impregnated with graphite for extra lubercation.
This will eliminate fragile pinion bearings and the need for a HD pinion modification.



Long term testing is motion!
 
I don't think it will hold for too long. Consider what will happen at the contact between pinion's steel (which is constantly pushed back by the crown) and the correspondent part of bushing, made from brass. I gave this a lot of thoughts (even what it will happen if using cage or needle bearings https://www.bocabearings.com/products/hk1512-20188, but I think there will be the same problem) and I believe you will have pure grinding on that point. Try at least to install a shim between pinion and bushing. I really hope this will work, as those lame bearings are barely doing their job.

Sent from my Sony Xperia Z5
 
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I've actually thought about altering the bushings shorter so a bearing would be used in between the bushing & pinion haunch. The bearing would be protected yet reduce friction that you speak of.
That is one of the issues that I had with the washer idea.. if the screws retain the washer the pinion must create friction?
Thanks for the positive criticism ! It's definitely a key attribute for US to resolve issues!



I don't think it will hold for too long. Consider what will happen at the contact between pinion's steel (which is constantly pushed back by the crown) and the correspondent part of bushing, made from brass. I gave this a lot of thoughts (even what it will happen if using cage or needle bearings https://www.bocabearings.com/products/hk1512-20188, but I think there will be the same problem) and I believe you will have pure grinding on that point. Try at least to install a shim between pinion and bushing. I really hope this will work, as those lame bearings are barely doing their job.

Sent from my Sony Xperia Z5
 
When I first put the new gears in I thought the pinion was too close to the ring gear but didn't know what to do so i ran em notchy. Both failed and pushed pinion out. Looking at the vid and whats involved I have a friend who is a machinist and I am going to let him play with the next set. Thanks for all your HARD work and helping all of us.

Well Steve it's been almost 10 months without a issue! I'm glad that you took minute to listen to what I was trying to say! You've been a great help to the community Pro Mod !
 
This is the sequence that I use for shim placement.

ON A BHB MODIFIED PINION

The Three bearings Must be exactly the same length as the (stock) Two bearings plus spacer BECAUSE that is the depth of the housing. If all of the shims are used within the bearing pack then when the pinion retaining screws snug down they will pinch the bearing pack and cause drag !!!!
Add the remaining shims on the OUTSIDE of the outer bearing filling in the void to the back of the c clip. This allows the remaining shims to fix the pinion in place. The last 4 shims are basically the amount taken off by the BHB pinion mod.

Which ever mod you choose make sure that the pinion pack is the same length as the factory specs"thumbsup"





And yes this is the original modified HD pinion with over 500+ runs and to honer it I'm installing it in my BOMBER XL




It looks like the 18x15x0.2mm are the shim for the differential. If you needed them would you ever need 0.1mm or 0.3mm shims? I can't seem to find this size except in the Axial 18x15x0.2mm shims.

BarHarborBasher, are these the shim you were talking about?

Thanks!






Those are the ones"thumbsup"

The bulkhead and rear axle have about .3 amount of horizontal lash... With the rear diff cover off push the diff tight to both sides wile turning the driveshaft... Shim the side that allows the smoothness feeling.


They slid over the output for simple adjust "thumbsup"




Note: the size difference between the pinion shims and the diff shims
 
The oillite bushing fits superb. Almost a pressed fit into the housing and a vacuum like fit around the pinion. I'm going to machine these up so that the HD gear pinion mod will be a thing of the past. I will be bench testing this weekend and taking temperatures and seeing how it performs under friction. I really have high expectations for this modification. It's lubrication coefficienticy say that it's able to lubricate under 850 pounds of bearing weight while performing it's assigned task.
 
That looks promising BHB! What machining are you having to do to it to prevent the need for pinion modification?


Sent from my iPhone using Tapatalk
 
That looks promising BHB! What machining are you having to do to it to prevent the need for pinion modification?


Sent from my iPhone using Tapatalk

I am counter boring the bushing for the pinion (haunch + back bevel of the teath) so that there pinion recesses into the correct position for optimal mesh. "thumbsup"
On Monday we are tooling up a cutting head
 
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Well it looks like the BHB bushing might even resurrect this old pilfered axle that I've been holding on to that was destroyed while I was figuring out HD pinion issue I think I've got like 3 of them kick it around.
I'm blown away at how cool the bushing has been staying during bench testing. I think this is gonna be good fellas!

 
Really interested to see how this turns out.

I can see no way how the 3 bearing mod would completely solve this issue.
Still, living in Europe (not that handy to send HD pinion to BHB or this other guy), and not having proper tools or place to do the mod myself I'm still super interested in finding alternative solutions.

BHB, I guess you're hands down the most familiar with the HD gears issue so a couple of questions: (I could probably find the answer by going through all these threads but at least after an hour couldn't find the final answers..)

1. Does the Dhawk V2 bulkhead now have the extra space to set the unmodded HD pinion further back? aka does it work solving the issue properly?
Anyone else who have tried it?

2. As an alternative solution (I think I have seen it somewhere here in the forums, so not my idea), how about adding a spacer in front of the first bearing, a spacer that would be exactly the thickness required and would contact just the outer side walls of the bearing.
Can anyone come up with something why this wouldn't work?
Should be too hard to massproduce those once you get the dimensions figured out.

Once again sorry if this is something that has already been discussed, but I guess I'm not the only European still trying to figure out what to do. (In the US I would have sent a whole box of HD gears to BHB...)
 
Still, living in Europe (not that handy to send HD pinion to BHB or this other guy), and not having proper tools or place to do the mod myself

I did the pinions myself, and so far they have been holding up great. Can't give guarantees, but seeing how I live relatively nearby, I can help you out by doing the mod for you. Let me know.
 
So I tried out the bushing in the stock axle housing and everything rotated nice and smooth and seemed very secure ! Unfortunately the heat generated from surface friction caused the stock axle to melt... I think I might free modify the bushing as a HD gear adapter substituting the shim spacer approximately 5.2 mm.. I think the bushing will work well in the aluminum axle housing I'll definitely know after testing.. I actually haven't had any issues after I installed the pinion Shield.







I also needed a Dhawk spacer so I took a 25 x 5 mm bearing that was worn out and remove the inner race as a pinion spacer only .2 mm shim was needed.. it's definitely a better option than waiting for the boat to cross the big pond.. your local hobby shop sells those bearings for Traxxas two for five bucks... Plus they're not aluminum they made out of stainless.

 
So I tried out the bushing in the stock axle housing and everything rotated nice and smooth and seemed very secure ! Unfortunately the heat generated from surface friction caused the stock axle to melt... I think I might free modify the bushing as a HD gear adapter substituting the shim spacer approximately 5.2 mm.. I think the bushing will work well in the aluminum axle housing I'll definitely know after testing.. I actually haven't had any issues after I installed the pinion Shield.







I also needed a Dhawk spacer so I took a 25 x 5 mm bearing that was worn out and remove the inner race as a pinion spacer only .2 mm shim was needed.. it's definitely a better option than waiting for the boat to cross the big pond.. your local hobby shop sells those bearings for Traxxas two for five bucks... Plus they're not aluminum they made out of stainless.

 
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