Kraton Ackerman play in Treal steering assembly

[BruceRC]

I'm wondering how tight you generally go with the screws that go into the ackerman M3x8x12 balls connected to the turnbuckles? Where you have the 2mm on top and the 2.5mm on the bottom. Do you go snug tight or snug and then back off a bit?

 

[Garcbomber]

Dab of Blue loctite under the head/into the threads and as tight as you can get the 2.5mm side with a hand driver while just holding the 2mm from spinning. Never had one loosen and does not require heat to remove later with good drivers.

 

[BruceRC]

Dab of Blue loctite under the head/into the threads and as tight as you can get the 2.5mm side with a hand driver while just holding the 2mm from spinning. Never had one loosen and does not require heat to remove later with good drivers.

Thanks, I was asking because if I do tighten them up as you suggest, I get this clicking:

Sorry about the quality, I probably should have zoomed in a bit. Kind of needed a third arm.

 

[Garcbomber]

Thanks, I was asking because if I do tighten them up as you suggest, I get this clicking:

Sorry about the quality, I probably should have zoomed in a bit. Kind of needed a third arm.

The servo post arm mount to ackerman bushing is loose or washer to contain it from exiting is gone.
The green circle assembly shouldn't have any vertical play.

Too tight and it'll start a bind interference, that's why there's a nylok nut on the bottom.

 

[BruceRC]

The servo post arm mount to ackerman bushing is loose or washer to contain it from exiting is gone.
The green circle shouldn't move vertically.

View attachment 361103

There is a tiny bit of play, like 1mm vertically with the ackerman. I've seen someone comment about this with the Treal before and I'm just wondering if this is a design thing with this assembly. It comes pre-assembled and those two ackerman bolts were set pretty tight. Maybe I should have tried tightening them up more?

 

[Garcbomber]

Ahh, so it's just the ball snapping in the female end link. You could deburr the ID if it's a brand new composite mold or I use Teflon tape wrapped around the ball when it starts wearing out over time.

That ackerman play will create slop in the steering assembly and additional toe out, but not really noticeable on a basher.

 

[Dan B.]

There is a tiny bit of play, like 1mm vertically with the ackerman. I've seen someone comment about this with the Treal before and I'm just wondering if this is a design thing with this assembly. It comes pre-assembled and those two ackerman bolts were set pretty tight. Maybe I should have tried tightening them up more?

Maybe not tightening them up more, but checking them and shimming if necessary, I do that with all steering racks. I’ve never actually bought one that came pre assembled.
If the top of the posts can rise, even 1mm, it could in some cases cause the Ackerman arm not to clear the top plate where it screws to the bulkhead. I’ve seen that before. The tolerances on the Scorched setups are super tight, for example. When using a BQ steering rack/servo saver they have to be shimmed well to avoid contact. When done right, they’re butter.

 

[BruceRC]

Follow up on this issue with the play in the Treal assembly. With some advice from @332_RC, who runs the same setup and encountered the same issue, I ended up adding two 5x10x0.5mm shims under each side of the Ackerman. This removed all the play that was there and I was able to get it buttery smooth.

There was also about 0.5mm vertical play on the spring side post. I put a 6x8x0.5mm shim under the top plate, above the bearing on that post.

Seems much better now. Thanks again @332_RC.

 

[332_RC]

Follow up on this issue with the slop in the Treal assembly. With some advice from @332_RC, who runs the same setup and encountered the same issue, I ended up adding two 5x10x0.5mm shims under each side of the Ackerman. This removed all the play that was there and I was able to get it buttery smooth.

There was also about 0.5mm vertical play on the spring side post. I put a 6x8x0.5mm shim under the top plate, above the bearing on that post.

Seems much better now. Thanks again @332_RC.

You're welcome @BruceRC anytime bro!