Notorious Diff pin snapping

[Lumsdenaj]

Hi guys . In a bit of a rush so I’m sorry for the lack off correct terminology. My rear diff keeps snapping the little pin that holds the gear in . always the one directly in front of the input gear (or behind depending how you look at it ) running 50k front 100k middle 30k rear diff is shimmed 1-2-2-1 going around any advice would be great

 

[jondilly1974]

You can make your own pins from drill blanks. Many members here do that. I am looking into buying tool steel quality drill blanks myself to do this as well. You should also look into the M2C output cups as they will be the next thing in line to break. Also make sure to shim behind the pin with the Mugen shims. They are wider than the stock shims and support the pins better.

 

[Lumsdenaj]

You can make your own pins from drill blanks. Many members here do that. I am looking into buying tool steel quality drill blanks myself to do this as well. You should also look into the M2C output cups as they will be the next thing in line to break. Also make sure to shim behind the pin with the Mugen shims. They are wider than the stock shims and support the pins better.

Sound advice. Thanks. I’m in the uk do you know anywhere I can get the shims because the postage costs more than the product haha

 

[jondilly1974]

Sound advice. Thanks. I’m in the uk do you know anywhere I can get the shims because the postage costs more than the product haha

https://www.ebay.co.uk/c/15024543071

 

[bicketybam]

What version are your diffs? If they are V4's you may have overshimmed them. I've never broken a pin in a V4 diff and I don't shim them either.

 

[Camaroboy383]

When they are available, the EXB diffs use different output cups with larger pins.. as well as a different internal gear set to compensate for the larger pins.. it's a common thing to snap the 2.25mm pins, if it wasn't, arrma would not have changed the pin diameter...

As mentioned above, drill blanks will get you out of a jam, and last longer if you can cut some..

Another thing to look at now that you have popped several pins is the pin bore in the output cup, they get all wollered out causing slop.. that slop converts to a snap beating the pin to death until it snaps.. if you cant pull the drive cup out of the diff cup easily, its wasted.. they should slide right out with no resitance...?

 

[L3phturn]

I see you saying "drill blanks" but I got nothing. How would I get these. Would a local machine shop have these and cut them for me? What material/length should I ask for?

 

[FatCatRC]

I see you saying "drill blanks" but I got nothing. How would I get these. Would a local machine shop have these and cut them for me? What material/length should I ask for?

https://www.ebay.ca/itm/M0-8-M2-9-1...var=472934235861&_trksid=p2057872.m2749.l2649

I see you saying "drill blanks" but I got nothing. How would I get these. Would a local machine shop have these and cut them for me? What material/length should I ask for?

The U.S outlet everyone here uses will not sell to us canucks unless we are a business or school. I ordered mine from ebay today the link is above. You can also get these https://www.amainhobbies.com/mugen-seiki-2.2x9.8mm-universal-joint-pins-10-muge0237/p29861

 

[jondilly1974]

I see you saying "drill blanks" but I got nothing. How would I get these. Would a local machine shop have these and cut them for me? What material/length should I ask for?

Hardened Undersized High-Speed M2 Tool Steel Rod, 2.25 mm Diameter, 2-1/4" Long

https://www.mcmaster.com/2900A239

 

[Camaroboy383]

I see you saying "drill blanks" but I got nothing. How would I get these. Would a local machine shop have these and cut them for me? What material/length should I ask for?

It's a drill bit that has not been cut..(drill blank)... a drill bit can be found at any store..just buy a good one.. it doesn't have to be a blank rod..?..

2.25mm x 9.8mm ✌

 

[L3phturn]

That makes sense, thanks guys! Ideally I find someone with a machine shop that orders such things anyway and can cut them for me if they don't come the right length. The Muegen pins are another good option.

 

[Camaroboy383]

That makes sense, thanks guys! Ideally I find someone with a machine shop that orders such things anyway and can cut them for me if they don't come the right length. The Muegen pins are another good option.

Pay attention if your gonna buy mugen sieki pins.. cause If memory serves correct, they are all 2.5mm not 2.25mm.. which means you will need to buy the output cups and internal diff gears to accept the mugen pins..