Help! Monster beetle, Mip super ball diff fitting problem

[Rayhoop 0]

Hi all, I've been searching the forum and the net in general to find a solution, but I'm not sure what I'm doing wrong. 

 

I'm building a mip super ball diff for my re-released Monster Beetle. Should be straight forward - I'm fairly technical, have read the instructions, watched the YouTube videos etc... 

My issue is I cannot get the screw + 5/64" ball bearings (with grease and washers) into the male outdrive.  The screw passes through the hole just 4-5mm, and the ball bearings appear to be caught on a ridge inside the outdrive.  The screw and washers pass through on their own without any issues, but not with the bearings...  I've attached a photo of where the assembly gets stuck.

Is this a common thing, that you just have to keep persevering with, or is something up with my product? 

Was there a slight ridge on the inside of your male outdrive?

I've been trying to get this resolved since yesterday.. I've contacted MIP and am awaiting a reply. 

Any thoughts or tips from the pros?

[Rayhoop 0]

In fact. I've tried assembling it a different way. I've put the first washer into the outdrive, and one by one dropped the ball bearings in to join it. 

I can only get 5 ball bearings to fit at one time (and they are tight),  and there is not enough gap to pass the screw through the middle.  I'm certain the outdrive requires machining out or the supplied ball bearings are too large. 

Measuring the ball bearings, my electronic vernier calipers reads 0.09inches.  I'm sure 5/64" equates to 0.078inches. It's close, and I suspect there is bound to be a margin of error when measuring with calipers. 

I can't get the calipers into the outshaft to measure the inner diameter. 

Any thoughts

[howaboutme 247]

I just built the Hotshot ball diff so maybe not exactly the same. I had no issues. Did you install the thrust balls in the thrust bearing assembly? It looks like the thrust bearing is caught in the outdrive? You're supposed to use the smaller ones there and the larger ones in the diff gear. Fit is perfect for mine.

[Rayhoop 0]

I did wonder that. 

I was given 6 larger bearings and enough small bearings to fit the diff gear (They do seem loose in the holes). They might have got the quantities of the bearings wrong. 

I've contacted the supplier, I'm confident they will help me out.  I'll update you guys once I have a solution 😊. 

I'm glad it is supposed to go together smoothly/easily. Reassures me that I'm not going nuts lol. 

[toyolien 4659]

I didn't have any issues with my mip diff in my frog. However, the thrust balls are a fair bit smaller than the balls that go in the diff gear.

[Lee76 638]

I’ve literally just finished building mine, it could be the balls or possibly the fastener shank diameter is large, those fasteners are rubbish quality. Have you another bolt to try? You could polish it down if it’s only a little too large? Put the fastener in a drill and grind it down a little. (I’ll retract this suggestion since I think in this case they mixed the quantities up)

I had a nightmare building mine, the quality of the parts is a little poorer than expected, the issue I had is that the stack height of the uncompressed spring was long (tolerance stack issue) meant the fastener couldn’t engage the dog without first compressing the spring which was impossible by hand. I drilled a hole in a piece of wood to take the out drive put a nail through the slot for anti-rotation so I could have something to push down on whilst keeping it all square. An extra 0.5mm of bolt length would have made this easy to fit...

 

 

[Lee76 638]

The 0.09” size does appear to be the 3/32 that should go in the diff gear.. the parts picker must have had an off day, were yours sealed in two separate plastic wraps, the 6 off and the rest?

[Rayhoop 0]

19 hours ago, Lee76 said:

The 0.09” size does appear to be the 3/32 that should go in the diff gear.. the parts picker must have had an off day, were yours sealed in two separate plastic wraps, the 6 off and the rest?

This is what seems to be the issue. 

I've 6 large ball bearings when I should have 14..

And 14 of the small ball bearings when I should have 6. 

The two sizes of bearings were in individual heat sealed pockets of the same packet.

The product is back in the post making it's way up to the retailer with a note to check their inventory of Mip diffs in case the same issue is effecting the rest of a batch.  Mip were in contact as I reached out to them on the weekend, I've updated them on my issue/finding too.

I can't wait to get this thing back up and running! 

[toyolien 4659]

@Rayhoop Did you get the MIP diff sorted?

[Rayhoop 0]

Hi!

Yes I did thank you.

I returned the contents to the retailer who promptly shipped a new unit. The bearings in the replacement were the correct size/quantity and it was vassembled with ease.

Both MIP and the retailer were very good at responding to my concerns. 

 

The Beetle is back up and running... With a brushless motor!  Lots of fun!

[toyolien 4659]

Lovely job. Thanks for replying.