Interesting Part Repair Ideas

[Casting Timmy]

Keyed 3-4 Hubs Re-Keyed?
I worked in an industrial manufacturing area for a while (Permatex) and remember broaching certain gears for new keys at times. Sometimes it was a key size change for a different shaft and other times it was to save an old gear to make it fresh again.

Has anyone re-broached a VW 3-4 hub? I would think a new key slot cut maybe 120 degrees out from the first one would make them servicable again on hubs with enlarged original key slots.

091 3-4 Keys
I know the stock 3-4 keys have a tendency to collapse or break the side walls, has anyone tried adding a little weld inside the keys instead of converting over to the 002 key style? I could see this being an option when wanting to use stock gears and hence stock synchros in an 091 and trying to give a little more life to the transaxle.

Brazed Fork Repair
I have a lathe and think a simple tooling set up could be done to quickly machine old worn forks that have been TIG brazed with Silicone Bronze to build the pads back up or add pads to early style forks. Would really love to make this work with early forks to get the circular fit up better so the whole fork pushes against the slider and not just the upper or lower portion of the fork. Any tricks for forks that tip in and out on the slider?

[Pablo2]

Hubs rekeyed: In the earlier days of off-road racing (when Type I mainshafts were used), some guys tried to add a second keyway to the hub and mainshaft. It didn't make any difference in longevity because the hardening wasn't there.

091 shift plates: I'm actually surprised no one (including me) has made stronger pieces to replace the OE 3-piece ones. But since most failures are likely due to reuse of an old part, simply replacing with new is probably the best option. It isn't like these are a high stressed part (unless continually speed-shifting).
For off-road, it still might be best to convert. https://www.thesamba.com/vw/gallery/pix/1144068.jpg

Forks: I suppose we've gotten to the point that good cores are near impossible to find. Brazing new pads on might be a good way to put an early forged 4mm fork back into service, or make a 5mm fork out of a 4mm one. I wouldn't bother with the later cast/sintered forks.

[Casting Timmy]

Very cool mod on the 091 slider!! Weddle now makes some some pieces to put an 002 hub on the 091 mainshaft, I'm not sure what other mods are required with it though. I guess that is also the old mod from Weddle and most will go with the MD2D hub or the "racing" Weddle hub.

I have though about it with the 4mm forks to save them, but my fear is that they might last longer than the steel and start to wear out the slider. I could see it being a good modification for a racer as maybe it would be more likely to finish the race with being able to last longer against the rubbing than the steel.

I did a recent 091 with Weddle gears and their floating hubs, those floating hubs are so nice! Just get to order the 002 or 091 hub depending on what synchros you are running.

I keep mean to compare the 002 wire springs to the 091 wire springs, I keep wondering if a rectangle piece inside the 091 catch key would be an easy modifcation with just being able to TIG/ spot it in a coulpe places and keep the sides from breaking and the catch key collpasing. I think off roading or heavy shifters would be better with the 002 conversion, but maybe an easy way to help a stock rebuilds not have a know issue lurking in them.

[Pablo2]

That's actually a 1990 mod page, superseded shortly after by thinner custom adapter thrust rings (eliminating hub side machining).

The free-floating hubs certainly make inventory more versatile. But some feel that the floating hubs make the synchros drag a bit. (Porsche uses that fit for their sequential boxes, but those don't have synchros or tapered cones.) Cone concentricity (with the gear bore) can only be guaranteed when ground last, after the bore is finish ground. But I do like the ease of switching from 091 to 002.