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Discussion Starter #42
Don't know what to tell you there. I am friends with my fastenal guy and he ordered them for me no problem.

J. J.
 

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2 things, the rams are .5 stroke each. The stak shift rails move .44" to each detent. Anyone see a problem using the .5" rams to push the stak rails?

I guess the first ram push could push the lever .05" too far on the first move, and then on the second move it would go all the way to lock and then be pushing on it...

I might give stak a call in the morning to make sure this is ok, before I drop 500 bucks. I guess I could also put a slight offset on the rams which would shorten their throw. The web site says you can also order cusions that will allow you to trim the throw slightly...

I wonder how much the .06" will matter
 

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Discussion Starter #44
Negative. There's only one supply of pressurized air per shift rail that goes into the switch.

J. J.
Oh, wait, I'm sorry. It's been so long since I've worked on these, I forgot how it actually worked. Yes, there is a supply to each of the spring valves that is not shown in that diagram. Totally my bad.

Which leads me to another point, I had to get a bunch of t's to get my supply lines from. They sell quick-connect t-fittings at Clippard also.

J. J.
 

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Oh, wait, I'm sorry. It's been so long since I've worked on these, I forgot how it actually worked. Yes, there is a supply to each of the spring valves that is not shown in that diagram. Totally my bad.

Which leads me to another point, I had to get a bunch of t's to get my supply lines from. They sell quick-connect t-fittings at Clippard also.

J. J.
No worries.

X-Rated said:
The stak shift rails move .44" to each detent.
I bet a sst washer would give you the 0.060". Or you should be able to order a custom stroke cylinder for not much more. I know Parker pneumatics are this way because they make every one by hand.
 

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I talked to stak. They said if we have solved the problem of getting to N, then it should work. He didnt like the fact the ram travels 1/2" and the shift rails are supposed to travel 7/16" though... The other problem I see is the shift rails are close together, I am not sure the rams will fit. Last problem, 2 rams stacked up ass to ass are going to be 10-11" long once the clevis ends go on, so clearance to the tranny could be a problem. I am going to call the ram company in the morning. They sell rams with cushions for more money, that all you to make the ram stop before the stroke end, so I am going to see if I got cushions on all my rams if I would be able to dial them in to exactly 7/16"

The other comment stak made was they think a hydraulic shifter would be better
 

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I bet a sst washer would give you the 0.060". Or you should be able to order a custom stroke cylinder for not much more. I know Parker pneumatics are this way because they make every one by hand.
Clippard says they do through to the closest .25" which doesnt really help me. :-(

Where would you put the washer? Stack mentioned you could probably take the ram apart and put a nylon spacer in it if need be, but that is a SMALL spacer :) and who knows how hard it is to take these things apart
 

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Where would you put the washer? Stack mentioned you could probably take the ram apart and put a nylon spacer in it if need be, but that is a SMALL spacer :) and who knows how hard it is to take these things apart
You put the washer(s) between the clevis and the wiper-seal face around the cylinder shaft. You want to shorten the retract stroke. You would have to put these spacers in before you fab your mount away from the t-case as the spacers will lengthen the retract-rectract state of the cylinders by 0.120". I measured some SST 1/4" washers I have at my desk and they range from 0.045 to 0.050 each.

I just talked to my purchasing guy at work and we get our Parker cylinders 1.06 diameter body, 0.500" stroke for $14.00 each. From what I can tell Parker doesn't sell the toggle switch with the flow states that Clippard does. So from what I can tell, Clippard is definately price competitive.
 

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http://www.clippard.com/pdf/byo/cylinder/ss/cut_away.pdf


can not be taken appart. Looks like the ends or clamped/pressed on, not threaded.... So I could still make a spacer on the outside that goes over the rod to limit it from pulling back into the cylinder the last 1/16
Yep, you can treat it just like a hydraulic cylinder for hydro-assit. You can limit it inside or out. Since the cylinder cannot be disassebled, just limit it's travel on the outside.
 

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I just worked through a logic table and the only way for the system to work is if the toggle valve is no power, power one side, power both sides. I sure wish they would post flow diagrams on clippard.
Rework your "logic table". ;)
 

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Do you have the flow diagrams for the valves? I am curious what happens when/if you lose system air pressure entirely.
If you lose system pressure, the pilots will lose their pressure and the spring return valves will revert to their default position. However, since there is no system pressure to actuate the cylinders, they will just stay in whatever position they are in. You're simply stuck in whatever drive range configuration you were in before you lost pressure. No big deal, except you can't shift the t-case unless you reach under the rig and manually shift to whatever range configuration you want. For this reason, it would be a good idea to have an access panel over the cylinders so you can access them from the top side.
 

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Rework your "logic table". ;)
I get it now... The valves were originally drawn as mirror images but then the cylinder air lines on the right were flipped. Both sets of airlines to the cylinders should be straight across (no "X") on the right side. OR the valve on the right should be the same orientation as the one on the left.

Of course the only scenario that I didn't check is the one that it is.
 

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i decided to get the upgraded seals and wipers. Only cost a few dollars more and they deal with the cold better. I acutally upgraded EVERY part to viton seals for that reason
 

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Some quicky schematics for the logically chanllenged. :flipoff2:

Green indicates pressure in a circuit.
Blue indicates circuit exhausted to atmosphere.
P = pilot port
S = supply port
 

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Also, if you want a rebuildable cylinder (or one that you can open up and limit on the inside) Grainger sells these Speedaire cyilders made by Dayton.



They are about $44 each though....
 

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Discussion Starter #59
See, ya'll are discovering why I went pneumatic now. It's going to be next to impossible to get your strokes exactly perfect for each application. In fact, one of the strokes on my front shift rail is slightly more than .5" because I had to grind that detent in the rail myself when I twin-sticked it. Plus, there is some play in the clevis pins that act as linkage. The important part when you set it all up is that you get the neutral position right. (One ram extended all the way, the other retracted all the way.) If the rams push or pull a little past high or low it's no big deal because the detents in the t-case will stop them and it will just compress the air a little bit. No big deal. So long as you are sure that the rams are getting all the way into both positions, you're fine. (What I mean by that is, make sure they're not limiting the travel and acting as stops.) So just set it up perfect for neutral and make sure you're getting all the way into high and low you'll be good.

I guess what Stak meant is a slave cylinder system using levers as the source of pressure, which would be cool and you wouldn't have to worry about strokes, but part of the bling factor of all this is not having shift levers.

They could also possibly be talking about a system with a pump, but then if you don't have your strokes just right, something is going to bend. Most likely the ram shaft.

J. J.
 
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