450 Slide-out FIX

[dentmac]

Pneumatics are the problem but perhaps Exterior is a better area for this post.
For the 450's , this site has been great. Thank you to everyone. Hopefully this will helps a few.
It may take a re-read it a few times to follow my logic.
But it works.

The slide pins have always been suspected of binding but in most cases that is not the issue.
Consider: When pushing the in or out button, you can hear the air (if visible, you can see the pin move a little) Upon button release, you can hear both pins “Bang” to the lock position- so BOTH pins had to move. If you release the air pressure and use the manual button to release all air pressure from the “Lock” side of the pin, the pin moves freely.

[davidbrady]

Hi Ross,

I think your Norgren valve is a 5/2 valve which would be 5 ports and 2 positions. I'm following what you're saying but I'm wondering why the spool doesn't move quickly or almost instantaneously. Is the valve air or electric solenoid piloted? I see what you mean about equal pressures at port 2 and 4 as the valve moves but those pressures shouldn't effect the rate at which the spool moves, and once the spool completely shifts into position the exhaust port is fully opened which should quickly release the pressure allowing the lock cylinders to move.

[dentmac]

Good morning,
You are correct--Norgren 5/2. (I sent an earlier reply but internet issues here.
Some of my logic is correct I believe but I'm wrong because I'm relating the continuous feed to 4 being from the norgren. The spool is electric controlled and I think it moves completely as you say.
But when the valve has moved, there is CONTINUOUS exhaust from 3 ,so there must be a feed from 1. When the pin moves, the exhaust stops. (so the pressure behind the ram is released.
Could the Ram/pin have an internal bypass?

Why would restricting flow and/or reducing psi help?

Probably not related but there are 2 pressure regulators off the aux compressor. A 35 and a 55 psi
One would be toilet. Other ?

The pins are not jammed.
Thanks,
Ross

(08-14-2013 21:55)davidbrady Wrote:  Hi Ross,

I think your Norgren valve is a 5/2 valve which would be 5 ports and 2 positions. I'm following what you're saying but I'm wondering why the spool doesn't move quickly or almost instantaneously. Is the valve air or electric solenoid piloted? I see what you mean about equal pressures at port 2 and 4 as the valve moves but those pressures shouldn't effect the rate at which the spool moves, and once the spool completely shifts into position the exhaust port is fully opened which should quickly release the pressure allowing the lock cylinders to move.

[davidbrady]

Hi Ross,

It's hard to visualize without a diagram, but I'm thinking that restricting the flow on port 1 works because this allows the flow on the exhaust ports to dominate.

Port 4 get's a steady flow, albeit restricted, which allows the pin to stay locked during bus transit. When the switch is thrown to retract the pins, port 4 still gets a steady flow but now port 2 is fed from port 1 pressurizing the cylinders to unlock. During the pin unlock phase port 4 is exhausted to port 5 and port 1 is directed to port 2. If the exhaust port dominates, meaning that it's flow is much greater than the source supplying port 4, then the locking pin moves as port 2 is pressurized. Confusing, I know, but I can see how restricting flow of the source at port 1 such that it's significantly less than the flow at the exhaust ports (which are vented to atmosphere) would allow the pins to retract even if a steady air supply is being directed to port 4. Whew!

If we had a diagram it'd be fun to try to improve on the design.

Thanks for the idea. I need to do something similar with my entryway stairwell cover. It behaves much like your locking pins except it doesn't have a continuous air feed on port 4 keeping the platform closed. This is a problem because my kids like to stand on the platform and lean against the dash. Without a steady air feed the platform opens with their foot pressure. I need to fix it!

[patticake]

Imagine the thought that went into that design. How big, how small, how much air pressure, what does what, etc, etc.

[dentmac]

Simply, bluntly and sadly, not enough thought! It doesn't work. Contacting the design engineering firm (Hamiltonits.com) did nothing. Ignored. There may have been some modification in the 2007 LXi.
Help here appreciated.

[Wanderer]

(08-16-2013 22:22)dentmac Wrote:  Simply, bluntly and sadly, not enough thought! It doesn't work. Contacting the design engineering firm (Hamiltonits.com) did nothing. Ignored. There may have been some modification in the 2007 LXi.
Help here appreciated.

I think we have traveled to far in the wrong direction when we start bashing our vendors. Many of us have dealt with this vendor and he is a stand up guy. He runs a highly thought of company. This system was designed basically by Bluebird and he was consulted and selected as a vendor.

Before we alienate these vendors/manufacturers, we need to understand their position. He is very willing to discuss issues and work with us to keep our slide electronics operational. He has parts and can make parts we need. He can troubleshoot, repair, etc whatever is needed.

We are luck to have him on our side, he could if he wished, just stop talking to anyone. I have no dog in this fight, just wish all could get along for the betterment of our coaches.

Contact him and discuss in a civil manner your issue.

[G.Kirby]

(08-17-2013 13:37)Wanderer Wrote:  

(08-16-2013 22:22)dentmac Wrote:  Simply, bluntly and sadly, not enough thought! It doesn't work. Contacting the design engineering firm (Hamiltonits.com) did nothing. Ignored. There may have been some modification in the 2007 LXi.
Help here appreciated.

I think we have traveled to far in the wrong direction when we start bashing our vendors. Many of us have dealt with this vendor and he is a stand up guy. He runs a highly thought of company. This system was designed basically by Bluebird and he was consulted and selected as a vendor.

Before we alienate these vendors/manufacturers, we need to understand their position. He is very willing to discuss issues and work with us to keep our slide electronics operational. He has parts and can make parts we need. He can troubleshoot, repair, etc whatever is needed.

We are luck to have him on our side, he could if he wished, just stop talking to anyone. I have no dog in this fight, just wish all could get along for the betterment of our coaches.

Contact him and discuss in a civil manner your issue.

Yes I agree. I have been to Ray Hamilton's shop and he has our slide system set up on a bench so that each board can be tested. He is a first class guy.