Build Project: Midnight Panic

[gt1guy]

20' of air is the proper way to break in a new rig every time.

 

[Austin]

For now I’ll just post a few pics & point out that I’m not disappointed in the truck at all for its first time out.

****'n A

 

[Penetrode Offroad]

****'n A

Absolutely. Thats a poster pic right there!

 

[ExWrench]

Gotta admit: that photo of the nose-wheelie knotted my stomach before I knew you didn't go over.

Wouldn't have been a big deal if it was a 'glass body (or just a Chevy ).

Skipped_Link - you're doing what many of us have only dreamed about - thanks for sharing

 

[Skipped_Link]

New YT is up covering the first event,
Also I'd like to point out that apparently a dual port pilot operated check valve or also refered to as a "lock valve" is pretty common to use on the rear steer in the monster truck world,
In short it locks the hydraulic fluid from returning back to the valve/pump unless pressure is applied to one side or the other,

I have one on the way, & I'll go over installation/operation next week while installing all the new parts!

 

[WaterH]

Great video and good show! I can’t believe how much you scheduled into your first outing.

Of course, I have questions. How is the ride compared to the buggy? In the inside shot, visibility looks terrible. I’m guessing that’s just an illusion. For example, when you drive through those entrances, it looks real tight. Is it easy?

Do you have radio contact with someone out side during a run? Like can someone tell you a cylinder is broke?

On the cylinder problem, unless I got this wrong, only rear cylinders broke. If that’s the case, could the spool in the rear be adding a lot of extra stress? (I think you said the front is open)

Anyways, thanks again for keeping us in the loop.

 

[Skipped_Link]

Great video and good show! I can’t believe how much you scheduled into your first outing.

Of course, I have questions. How is the ride compared to the buggy? In the inside shot, visibility looks terrible. I’m guessing that’s just an illusion. For example, when you drive through those entrances, it looks real tight. Is it easy?

Do you have radio contact with someone out side during a run? Like can someone tell you a cylinder is broke?

On the cylinder problem, unless I got this wrong, only rear cylinders broke. If that’s the case, could the spool in the rear be adding a lot of extra stress? (I think you said the front is open)

Anyways, thanks again for keeping us in the loop.

It was definitely a busy weekend!

As far a ride, the small stuff is no where near as nice as the buggy, the bigger hits are fine though,
I would never try to jump the buggy half as big as that last jump in Santa Rosa, & in the truck that landing was quite pleasant,
I know our heads move a lot in the GoPro, but it seat feel nearly as bad as it looks,

I’m new to the mt stuff so still learning, but I do remember seeing on video one time Ryan Anderson said his truck was setup for big air, & could take a huge hit, but sound about throw you out if the seat if you drive over a 2x4
He did a thing with hoonigan on YouTube that most of you guys would probably find pretty interesting, it was a 2 or 3 parts deal if I remember right.

We haven’t done it yet, but I could easily be in contact with someone outside, both Alison & I have our helmets wired with coms, & I also setup a headset for a crew person,
I’m still getting comfortable with a routine in the truck before I throw that in the mix.

The rear is spooled, & I believe that is enhancing the problem, but I’m not taking to spool out, so I’ll have to figure out the root & solve that,
I really think controlling the hydraulic oil better will be the correct repair.

Overall the truck is MUCH bigger, so navigating in the pits & through gates definitely requires some caution until I really get settled in the new truck,

 

[SLOWPOKE693]

Skipped_Link, Wouldn't adding over center valves to the rear steer system solve that problem permanently? They would require a bit of extra plumbing between the pressure lines on the cylinders, but would hold them steady when no steering input pressure is applied. All the cylinders on our drill rigs run those and they don't budge unless you pull a lever. I don't think flow control valves alone will solve the flopping problem, you need to keep the fluid in the cylinders from moving at all, not slow it down.

 

[SLOWPOKE693]

Btw... Congratulations on the successful first test drive!!

 

[SLOWPOKE693]

This is an example of what Im talking about...

This is the block mounted directly to each end of the cylinder where the pressure ports are. There is a cartridge in each that seals the cylinder off until it sees pressure from the opposite port, at which point it opens and let's fluid flow out. The cartridges can be adjusted to different settings to speed up and slow down flow in or out, acting like flow control valves.

 

[Skipped_Link]

Skipped_Link, Wouldn't adding over center valves to the rear steer system solve that problem permanently? They would require a bit of extra plumbing between the pressure lines on the cylinders, but would hold them steady when no steering input pressure is applied. All the cylinders on our drill rigs run those and they don't budge unless you pull a lever. I don't think flow control valves alone will solve the flopping problem, you need to keep the fluid in the cylinders from moving at all, not slow it down.

Actually the valve I have coming is similar to what you are describing,
The flow control valves were my initial thought to just keep the cylinders from slamming to the stops, almost like valving in a shock,
Since then I've decided to go with a dual port pilot operated check valve, so like you are describing, the check valves hold the oil in the cylinders, not allowing anything to move, then when pressure is applied to steer one direction, that pressure is also applied opening the check allowing oil to return to tank from the other side of the cylinder,
It's just a simpler less precise counter balance or over center valve,

 

[SLOWPOKE693]

Actually the valve I have coming is similar to what you are describing,
The flow control valves were my initial thought to just keep the cylinders from slamming to the stops, almost like valving in a shock,
Since then I've decided to go with a dual port pilot operated check valve, so like you are describing, the check valves hold the oil in the cylinders, not allowing anything to move, then when pressure is applied to steer one direction, that pressure is also applied opening the check allowing oil to return to tank from the other side of the cylinder,
It's just a simpler less precise counter balance or over center valve,

Sounds like you are thinking about the same thing I am. Good deal, that should solve your flopping problem in the rear.

 

[Mr. Mindless]

curious if that'll defeat the crossover relief or be plumbed to a big hit can still bypass to allow the tires to move and hopefully not break things. delicate balance needed there...

 

[CarterKraft]

Actually the valve I have coming is similar to what you are describing,
The flow control valves were my initial thought to just keep the cylinders from slamming to the stops, almost like valving in a shock,
Since then I've decided to go with a dual port pilot operated check valve, so like you are describing, the check valves hold the oil in the cylinders, not allowing anything to move, then when pressure is applied to steer one direction, that pressure is also applied opening the check allowing oil to return to tank from the other side of the cylinder,
It's just a simpler less precise counter balance or over center valve,

curious if that'll defeat the crossover relief or be plumbed to a big hit can still bypass to allow the tires to move and hopefully not break things. delicate balance needed there...

I think you still want the crossover relief near the cylinders.

Or at minimum have reliefs in the pilot check valve. In my experience pilot check valves are not relieved, they are designed to hold pressure no matter what, ie cranes, aerial work platforms etc. so while they sound ideal they are not what is needed for transient pressure spikes.

If the pressures/impacts are violent enough to snap those eyes off running a non vented system is going to cause even more damage every where else.

 

[CarterKraft]

Remember this banana, this was from a failed relief valve and was not from impact but a issue where the loader geometry requires the tilt cylinder to crack the relief valve if the bucket is full rack back and the loader is loaded to the stops.
It did not fail the hose the 3 times it bent this cylinder.

 

[Skipped_Link]

They eyes were ripped off because the steering had a run at it, (steering was forced one direction until it hit the end of the stroke, then “pop”) stronger attachment cannot hurt there either.

It’s easy to drive a nail in when you can swing the hammer,
Keep that hammer planted on the head of the nail & it becomes much harder,

A cross over bypass would certainly add a level of security for the parts, but I want to start with the tires not being able to move uncontrolled, & work from there.

 

[CarterKraft]

They eyes were ripped off because the steering had a run at it, (steering was forced one direction until it hit the end of the stroke, then “pop”) stronger attachment cannot hurt there either.

It’s easy to drive a nail in when you can swing the hammer,
Keep that hammer planted on the head of the nail & it becomes much harder,

A cross over bypass would certainly add a level of security for the parts, but I want to start with the tires not being able to move uncontrolled, & work from there.

I was thinking about this on the pooper today.

Are there physical stops for the steering? If one side is in tension the other side should be compression and I'd think you have it where the compression is the stop not the tension.

Not sure that makes sense but "pulling" the eyes off seems like a stop problem not a hydraulic problem.

Also since you are so good at machining you might think about putting snubbers in the cylinder rods, or pistons. That would cushion the stops if the hydraulics loose control.

 

[WaterH]

I was thinking about this on the pooper today.

Are there physical stops for the steering? If one side is in tension the other side should be compression and I'd think you have it where the compression is the stop not the tension.

Not sure that makes sense but "pulling" the eyes off seems like a stop problem not a hydraulic problem.

Also since you are so good at machining you might think about putting snubbers in the cylinder rods, or pistons. That would cushion the stops if the hydraulics loose control.

My thinking about this is it would be true if he was going to the stops all the time. Meaning, obviously he doesn’t hit the stops on the front steering very often because that’s just the nature of a steering wheel. But I think he has the option of snapping a toggle switch on the rear that makes the rear go “all the way”. I would guess he would use that in freestyle driving. I still ponder why the rears broke and the fronts didn’t. Other than the spool, this is the only thing I can think of.

 

[rattle_snake]

I was thinking about this on the pooper today.

Is that where you do your best work?

 

[CarterKraft]

Is that where you do your best work?

About the only place I can get peace and quiet at work

 

[Skipped_Link]

Are there physical stops for the steering? If one side is in tension the other side should be compression and I'd think you have it where the compression is the stop not the tension.

Not sure that makes sense but "pulling" the eyes off seems like a stop problem not a hydraulic problem.

That is one of the down sides to the pettibone corners, they do not have a physical steering stop, where I believe both the Clark & PS250 both do.

Some P-bone guys add stops, some do not,
I have a plan to build some stops that will bolt to the knuckle, & contact the champagne at the flange,
I do believe real stops would have prevented a lot of damage.
I believe you are correct about the extending cylinder stopping first, having the compressing cylinder bottom out first would be considerably stronger, (the modifications I made this week in fact changed the compressed length just enough that the extending side is no longer stopping the steering)

I still hold the opinion that lack of hydraulic control is the reason the physical limits are reached with enough momentum/force to break the parts,
That said, physical stops are still going to be installed, even if the dual check seems to remedy the issue.

My thinking about this is it would be true if he was going to the stops all the time. Meaning, obviously he doesn’t hit the stops on the front steering very often because that’s just the nature of a steering wheel. But I think he has the option of snapping a toggle switch on the rear that makes the rear go “all the way”. I would guess he would use that in freestyle driving. I still ponder why the rears broke and the fronts didn’t. Other than the spool, this is the only thing I can think of.

The front has probably double the lock to lock cycles at the rear,
The difference is hydraulic control, the HMU or orbital valve allows the same amount of fluid to return to tank as what it outputs to the cylinders,,,,so the cylinders cannot “flop” to the end of the stroke.
I agree with you, the spool in the valve is to blame, even if not faulty, it’s just not designed to hold that load.




This days off was pretty much dedicated to cylinder & rear steer repair,
Starting with 2 new cylinders, I drew up a reinforcing ring to go around the swivel eye that is welded to the barrel end of the cylinder,
Then I made a trip to the Plasmacam to cut those parts out along with a spanner wrench that fit the gland of these cylinders.

Armed with a new tool, I pulled the new cylinders apart, as well as two of the damaged ones.
Once disassembled I put the rod in the chop saw, & cut the swivel eyes off, I save to two off of the new cylinders, & cleaned them up to reuse on the old cylinders.

All 4 rods were run through the lathe where they were drilled & tapped for a 1”-14 thread,
This made it easy to adapt a common Heim joint.

I didn’t get any pictures, but I ended up building an aluminum collet so I could grab these in the lathe without damaging the chrome.

Next up while everything was apart, the broken swivel eyes were cut off the two used cylinders, & replaced with the new swivel eyes cut off the new cylinder rods,

Then the reinforcement rings were welded to all four cylinders.

Also while apart, I machined the fitting bosses down .300 on the new cylinders to match the original pair, (more clearance near the axle housing)
While everything was removed I also got a good look at the poor quality machine work & even a little surface rust inside these barrels, fortunately a friend of mine had a hone that fit this bore perfectly, so I cleaned them up real nice before scrubbing them in the solvent tank, & finally reassembly.

Above are the two cylinders I broke (twice) & the last one I broke in Washington. I have everything to repair the top in in the pic & will be doing that asap so I’ll have a good spare,

The two new cylinders that got the same treatment will be going on the front axle.

If all of this turns out to work properly, then the two front cylinders will end up being worked over as well, that will give be 3 spares,

After a little cleanup yesterday, & machining a few spacers down to fit the new heim joints, I got the rear all re assembled,

I also got the pilot operated check mounted & new hoses built, this time plumbing in both ends of the cylinders.

When I ordered the rod ends I ordered 5 right hand thread joints,,,,they sent me 3 RH & 2LH, so I could not get the front cylinders installed, but I reached out to the company I bought them from, told them what happened & they have another pair of right handers headed this way, so I’ll do that first thing next days off.

I did pull the cartridge out of the solenoid valve & carefully looked it over, I don’t see any damage & everything moves freely, so that got reassembled, the fluid filled & tested,
The rear steer is definitely slower, as expected being plumbed into both ends of the cylinders,
I’m going to try it as is, if it’s to slow, I may end up wiring the pump 24 volt for more speed,

We’ll see on that part later on.

 

[WaterH]

This is a totally cool pic. (To me) I just love all the silver links going everywhere.

 

[CarterKraft]

That is one of the down sides to the pettibone corners, they do not have a physical steering stop, where I believe both the Clark & PS250 both do.

Some P-bone guys add stops, some do not,
I have a plan to build some stops that will bolt to the knuckle, & contact the champagne at the flange,
I do believe real stops would have prevented a lot of damage.
I believe you are correct about the extending cylinder stopping first, having the compressing cylinder bottom out first would be considerably stronger, (the modifications I made this week in fact changed the compressed length just enough that the extending side is no longer stopping the steering)

I still hold the opinion that lack of hydraulic control is the reason the physical limits are reached with enough momentum/force to break the parts,
That said, physical stops are still going to be installed, even if the dual check seems to remedy the issue.

The front has probably double the lock to lock cycles at the rear,
The difference is hydraulic control, the HMU or orbital valve allows the same amount of fluid to return to tank as what it outputs to the cylinders,,,,so the cylinders cannot “flop” to the end of the stroke.
I agree with you, the spool in the valve is to blame, even if not faulty, it’s just not designed to hold that load.




This days off was pretty much dedicated to cylinder & rear steer repair,
Starting with 2 new cylinders, I drew up a reinforcing ring to go around the swivel eye that is welded to the barrel end of the cylinder,
Then I made a trip to the Plasmacam to cut those parts out along with a spanner wrench that fit the gland of these cylinders.

Armed with a new tool, I pulled the new cylinders apart, as well as two of the damaged ones.
Once disassembled I put the rod in the chop saw, & cut the swivel eyes off, I save to two off of the new cylinders, & cleaned them up to reuse on the old cylinders.

All 4 rods were run through the lathe where they were drilled & tapped for a 1”-14 thread,
This made it easy to adapt a common Heim joint.

I didn’t get any pictures, but I ended up building an aluminum collet so I could grab these in the lathe without damaging the chrome.

Next up while everything was apart, the broken swivel eyes were cut off the two used cylinders, & replaced with the new swivel eyes cut off the new cylinder rods,

Then the reinforcement rings were welded to all four cylinders.

Also while apart, I machined the fitting bosses down .300 on the new cylinders to match the original pair, (more clearance near the axle housing)
While everything was removed I also got a good look at the poor quality machine work & even a little surface rust inside these barrels, fortunately a friend of mine had a hone that fit this bore perfectly, so I cleaned them up real nice before scrubbing them in the solvent tank, & finally reassembly.

Above are the two cylinders I broke (twice) & the last one I broke in Washington. I have everything to repair the top in in the pic & will be doing that asap so I’ll have a good spare,

The two new cylinders that got the same treatment will be going on the front axle.

If all of this turns out to work properly, then the two front cylinders will end up being worked over as well, that will give be 3 spares,

After a little cleanup yesterday, & machining a few spacers down to fit the new heim joints, I got the rear all re assembled,

I also got the pilot operated check mounted & new hoses built, this time plumbing in both ends of the cylinders.

When I ordered the rod ends I ordered 5 right hand thread joints,,,,they sent me 3 RH & 2LH, so I could not get the front cylinders installed, but I reached out to the company I bought them from, told them what happened & they have another pair of right handers headed this way, so I’ll do that first thing next days off.

I did pull the cartridge out of the solenoid valve & carefully looked it over, I don’t see any damage & everything moves freely, so that got reassembled, the fluid filled & tested,
The rear steer is definitely slower, as expected being plumbed into both ends of the cylinders,
I’m going to try it as is, if it’s to slow, I may end up wiring the pump 24 volt for more speed,

We’ll see on that part later on.

The repairs look good and are smart for what you're doing, give you some repair adjustment options if failed.

Does the pilot lock valve have pressure relief valves in it?

 

[Skipped_Link]

Does the pilot lock valve have pressure relief valves in it?

No, the diagram for this block does not show any of that,

To get that feature a guy would have to do something like the over center valve mentioned a few posts up,

 

[Wendle]

The guy I buy my steering gear off is industrial, rather than automotive, based and he just always includes a pilot-operated check valve without me even asking.
I asked him about it once when I realised no-one else was running one and his attitude was basically that it is just dumb not to as without it you are expecting a metal to metal interface to seal well enough to stop any drift.

 

[Skipped_Link]

Just another recap of what you guys already know.
Credit goes to WaterH for the thumbnail choice!

 

[Grendel]

But you didn't post the best pic...

 

[CarterKraft]

No, the diagram for this block does not show any of that,

To get that feature a guy would have to do something like the over center valve mentioned a few posts up,

I was only asking in the instance let's say that you come down off a big jump and land on the "point", the corner of one wheel not flat to the ground and load it really fast and with a lot force would it just pop the hose, buckle a cylinder or just take it?

I assume if you are copying known equipment it's a non issue it's just surprising to me that they would not run reliefs in the circuit, the same cross over block between the pilot check valve and the cylinders would do it.

 

[Skipped_Link]

But you didn't post the best pic...

That is a great pic!

I was only asking in the instance let's say that you come down off a big jump and land on the "point", the corner of one wheel not flat to the ground and load it really fast and with a lot force would it just pop the hose, buckle a cylinder or just take it?

I assume if you are copying known equipment it's a non issue it's just surprising to me that they would not run reliefs in the circuit, the same cross over block between the pilot check valve and the cylinders would do it.

From my understanding monster jam does that,
But,,,, apparently the cross over bypass still lets the rear tires flop back & forth to a certain extent, & they rely on the auto center to straighten the rear tires when it does,
I already know the result of uncontrolled steering,

If I find the limits of controlled hydraulics & mechanical parts, I’ll look for a solution to that problem.

After seeing the inside of the cylinders, if the truck takes a hit like you’re saying (completely possible) & there is a mechanical failure, I’m going to guess it’ll break the piston off the rod,

 

[CarterKraft]

That is a great pic!



From my understanding monster jam does that,
But,,,, apparently the cross over bypass still lets the rear tires flop back & forth to a certain extent, & they rely on the auto center to straighten the rear tires when it does,
I already know the result of uncontrolled steering,

If I find the limits of controlled hydraulics & mechanical parts, I’ll look for a solution to that problem.

After seeing the inside of the cylinders, if the truck takes a hit like you’re saying (completely possible) & there is a mechanical failure, I’m going to guess it’ll break the piston off the rod,

Hopefully it just pops the hose before mechanical failure, cause mechanical failure can be un predictable.

In the very last part you mentioned it was plumbed differently than before and thus now slower, I assume it was in parallel before and now series, or vice versa?
I'm sort of confused as to how that would work, I might need to draw that out to see what was going on.