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Quick Change TopHat Questions

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This topic contains 12 replies, has 9 voices, and was last updated by  rrdstarr 1 year, 6 months ago.

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  • #17787

    mikesd
    Member

    A few simple questions. I understand how to install this but like to understand everything before I make any changes.

    1) This may seem stupid but does the tank have to be empty, before installing the quick change tophat? I’m thinking no but duh! Seems that would be in the instructions, one way or the other.

    2) When I got my hi-flow, spin-loc tank, it was completely empty. I could spin he tophat while it was in the tank. NOT the adjustable part but the entire tophat would spin freely. But it would not pull out, easily. I didn’t try to pry it out, as in the instructions. Just something I noticed. This makes me think the end is press fit into something that is free to spin, until filled. Once I filled the tank that spin stopped. Should the tophat, in an empty tank, spin freely?

    3) The video says to use in Hi-Flow tank. Is that the only tank this works with, even though it might fit?

    4) Which option most closely resembles the original tophat, in a Hi-Flo tank?

    a) No restrictor
    b) Large restrictor
    c) Small restrictor

    5) Going from adjustable tophat, to fixed, seems to suggest losing something? The restrictors, in the quick change, control flow amount. The adjustments, in the original, control opening and dwell. So, one design doesn’t necessarily replace everything the other had. Is there ANY functionality lost, by going from std. tophat to the quick change top hat?

    One thing that seems obvious but maybe not so, is that the original had some control over how far the valve opened and how long it stayed open. This was accomplished by moving the tophat closer or further from it’s strike point. That control no longer exists. OR, can the same thing be accomplished another way (i.e. power wheel).

    So

    Positives:
    Quick Change Tophat: no set screws to come loose
    Original Tophat: Full adjustability

    Negatives:
    Original Tophat: set screws come loose
    Quick Change Tophat: ?

    Is there any negatives to the Quick Change? Does it work equally well with all tank types (Std, Hi-Flo, Direct, Micro, etc) or is it for one type only?

    #209404

    toad-monster
    Member

    I think an original tophat has a huge flaw… That’s its durability and reliability. For example my condor ss was shooting 1024 fps on the lowest setting straight from the box. Since I could no longer get any adjustment from the power wheel (because it was already at 0.0) I had to adjust the top hat. I loosened the screw and screwed it in. I was amazed to see how little you have to screw in to change power I went about 2 turns and was shooting 450 fps. Too slow so I backed back out and was shooting 850 fps and then I locked it down tight. So now I can adjust from 850 fps to about 950 fps with the power wheel which is where I want mine to shoot.

    So basically the original does work perfectly and will change the fps. just as well as the talon tunes top hat… However it is not made to be constantly adjusted like this. For one the top hat grub screws do dimple the valve stem, and over time you will strip the screws from constant adjustment and if you dont get it tight enough it will move with the force from the hammer hitting it and over time will adjust itself.

    So whats the solution… well you could have several top hats that you have adjusted to where you want them. You could have one at factory settings, one for accuracy and target outdoors and one that shoots quiet and is for indoors. To switch you would have to remove one valve stem and replace it, which over time could lead to other problems. Or you could accomplish the same thing and buy a talon tunes top hat. Then instead of removing the tophat and replacing it or constantly adjusting the original and eventually ruining it, you just replace the insert size.

    TT tophat allows adjustment of the top hat as it should be. The AirForce top hat isnt made for adjustment beyond the original setup. Period.

    You see airforce doesnt understand that sometimes you dont want to shoot at a rip roaring 45 fpe all the time. They say you bought the condor and it shoots perfectly at this insane factory setting which is perfect and no one would ever want or need to change it, because guess what if you change it you no longer have a condor. blah blah blah. 🙁

    #209405

    maw
    Member

    Don’t forget a little blue loctite on the grub screws will keep top-hat secure.

    #209502

    mikesd
    Member

    I did get the Talon Tunes top hat. It’s in the photo. Just haven’t installed it yet. Been playing with my TalonP. I’ll get back to the CondorSS later. Have the chrono setup in the house, in the indoor range now, so I can test before and after.

    #210675

    dougroundup
    Member

    Mike, I believe that you are sound in your reasoning. As the adjustment does in fact greatly effect the metering of the air thru the overall length of stroke.
    Similiarly to control the metering of air, the TTOPTH meters the air with inserts. The inserts thread into the stem to obstruct the total air flow thru the valve. Very much similiarly to carburetor jetting.
    This seems to be a fairly workable solution that works satisfactory for majority of normal applications. The possible trade off might be an increase or decrease of back pressure as the orifice sizes change. Any neglible amount can be compensated via the power wheel.
    Also, another trick to mange the overall stroke of a onepiece tophat is to employ various thicknesses of shims under the tophat to reduce its travel.
    Often times in conjuction with both adjustable and one piece style tophats, a twofold advantage is realized by placing an Oring under the tophat. Utilizing an Oring to take up the travel, reducing the stroke has the added benefit of cushioning the violent force of slamming the valve stem full travel and rebounding off its stop against the tophat. A hard bounce condition that can actually decrease dwell time in a inconsistent way.
    As mentioned earlier it could be possible to have specific custom lengthed/custom ported, application specific one piece tophats constructed for a very specific tune.
    In most very high performance and high power applications one piece valvestem tophats are always utilized.
    Such as with the high powered custom built valve assemblies made by Dyotat. These valve are powerhouses built to push the highest envelope of performance. These applications are custom purpose bigbore guns. Custom built to launch cast bullets with comparable ballistics of firearms.
    These types of valves are redesigned and built from scratch. Utilizing just about every trick n the book! You might think of it similiar to how an automotive enthusiast might port and polish the intake of an engine. The airflow around and actual shape of the valve, the size of the opening and shape of the inletted ports, the diameter of the stem and tophat orifice and total stroke, the smooth unrestricted passage of air, especially reduction of turbulence such as the threaded length of a one piece tophat stem might introduce.
    In these applications, the tophat is specific custom fabricated made to fit deal. One size doesnt fit all. Regardless some amount of fine tuning will exsist and is all the more critical. Once again Dyotat will utilize various thickness hard rubber shims to mangage over travel and control the metering of air. Powerwheel setting having the largest effect on the dwell time of the metered air.
    For most average users and applications, the consistientancy and ease of use utilizing the one piece tophat and metering the air thru inserts or “jetting” is the simplest and most favorable solution.
    I would tend to agree that the adjustable tophat gives you infinite more adjustment but is more difficult to get right and has the possibility of going loose. The one piece is much simplier to set and forget and the limited adjustment is more than adequate for most applications with greater ease and repeatabilty to change.
    The stems do simply pry out. They are pressfit into the actual delrin valve. The delrin valve is held in place within the port of the valve body through the combination of a return spring and air pressure.
    I WOULD ADVISE AGAINST REMOVING AND REINSTALLING A STEM ON AN EMPTY TANK.
    The air pressure is needed to hold the delrin valve against the seating surface when the stem has been removed. The return spring doesnt have enough force to keep the actual valve squarely seated against the bearing surface of the port in the valve housing.
    NEVER UNSCREW A VALVE HOUSING OR COMPLETE VALVE ASSEMBLY FROM A PRESSURIZED CYLINDER.

    #214875

    bugout
    Member

    dougroundup-

    you state “I WOULD ADVISE AGAINST REMOVING AND REINSTALLING A STEM ON AN EMPTY TANK.”

    just wanted to get your take then on something i am about to do… i am planning to install the TT adjustable top-hat into a tank but this tank is current normal-flo (not hi-flo); so i bought the OEM parts from AF directly to convert the normal-flo tank to a hi-flo tank. in order to perform the conversion i need to degass the tank and remove the valve assembly, once rebuilt with the hi-flo components i was going to install the TT adjustable tophat and using my fill adapter re-pressurize/ fill the tank.

    reading over your statement/ reasoning – should i not do it this way? i dont know of another way.

    please advise.

    #214958

    knifemaker
    Member

    Yes, you will need to degas in order to exchange out the full valve assembly to fast flow. The TT will not fit a standard valve assembly. It is larger in dia.

    When a tank is empty, yes, the valve stem will be able to be rotated freely, as there is no pressure on the valve seat/seal. Once under pressure, it will not spin freely.

    The valve stem it’s self can be pried out of the valve body when, and only when the tank is under pressure. The valve will not move, as it is under a LOT of pressure. When the bottle is empty, there is nothing to keep the valve seal in contact and alignment with the valve seat. Not good! LOL!!! 😉

    Knife

    #215427

    bugout
    Member

    Update…

    Converted a quick detach, reg-flo to hi-flo tank.

    I think I understand now the tricky tophat seating issue discussed above – I actually got a small brass hammer and lightly tap, tap, tap the tophat to have it fully seated into the delrin piece – wouldn’t push in by hand at all.

    + posted thread on bill of materials/ parts list and approx cost for conversion

    #267208

    julio1221hz
    Member

    How to remove the stem valve from condor ss airtanks ..,.im getting the quick change top hat and need to know how to install it.

    Does the tank need to be empty ?

    Does the stem valve and top hat just pull off ?

    And tools i need to install the quick change top hats ?

    #267276

    dougroundup
    Member

    Julio 1221hZ,

    If you sesrch the Forums you will find some how to videos showing how simply this is accomplished. BASICALLY…. The best tool would be any thing that you can make, rig, fabricate or fashion to resemble a minature “pickle fork” tool like the type a mechanic uses to seperate a ball joint or tie rod. The idea is to pry the stem up and out of the actual valve and remove from the valve body guide. As previous noted in the above previous posts…. this is done while the tank is still pressurized. This pressure is what keeps the actual valve seated against the valve face and holds it in proper alignment with the valveguide, while you pressfit the new tophat stem. It is really very simple and takes much less time to do then it takes for me to write about and explain how to do it for you….. If ya didnt see the warning from the above posts…
    PLEASE NEVER TRY TO REMOVE A COMPLETE VALVE ASSEMBLY FROM ANY PRESSURIZED CYLNDER!
    It has been awhile since I have posted on these fine forums , and/or strayed off topic/hijacked thread! Hello old friends! Hope everyone is well and welcome to the new users that I have missed out on meeting. TAG is a kickass forum.

    #274182

    calinb
    Member
    quote dougroundup:

    Julio 1221hZ,

    BASICALLY…. The best tool would be any thing that you can make, rig, fabricate or fashion to resemble a minature “pickle fork” tool like the type a mechanic uses to seperate a ball joint or tie rod….

    Here’s what I use. (I have a couple of these kits):
    https://www.harborfreight.com/nylon-pry-bar-installer-kit-4-pc-69668.html

    I use two of the pickle forks from opposite sides (with the forks overlapping a little at their tips). The prying force is then very even and the nylon tool is non-marring and non-damaging to o-rings!

    BTW, I’ve found that o-ring hardness varies quite a bit with temperature changes so this winter I’ve been experimenting with top hat spacers/cushions that I 3D print from various soft and flexible materials that are more stable with temperature change.

    #274183

    dougroundup
    Member

    Excellent tip. Thanks for the link. !

    #274184

    rrdstarr
    Member

    I have a small Pony, branded, pry bar-screwdriver I have modified to remove top hats for AF rifles. They are $7.50 plus postage and work like a champ and don’t dig into the top hat or the valve seat.

    Pm me if you are interested.

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