Voltar’s take on the Selph made Blod valves
Well fellas I received two different valves as of today.
My first impression is that this is a nicely made unit. Nice clean threads, clean lines and a well thought out burst disk.
Valve body oring groove is not deep enough for the oring used as noted by Pabs.
Tophat should be longer to allow user to keep his breech slide stock.
Tapping the tophat has swollen the mouths of the two I have and so likely be tough to slide the breech home.
Valve stem is the weak point of this Selph made valve.
The bore is at 0.197″ and the od at the end of the threads is 0.234″
leaving a very thin wall of 0.0185″ where it takes a pounding opening and a stretch on the closing of the valve.
It is some grade of SST apparently as it is not magnetic. So may not be the best material for the job. Obviously it is weak as a number have broken already.
What my intentions are is to make a replacement stem for these valves and test for function before returning them to their owners. Thanks fellas 🙂
Will keep you all posted on progress.
Walter….
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Thanks fellas.
What I am hoping to clarify is the distance from the valve body to the cocking handle sleeve on a gun with a tophat adjusted for minimal slop.
Thanks again
My talon and my condor measure the same. Breech cutout is 1.498″, probably 1.500″ is close enough. this is the cutout only, not measuring the collar area.
Breech length is 2.005″ so probably should be 2.000″
The knob hole centerline is .475″ back from the front face of the breech.
walt
Walter;
Had a perusal through the drawings I have, and started scratching my head.
It seems I’ve a set of drawings (partials anyway) for a talon…and a condor.
Wouldn’t seem to be a problem, but when compared, the breech cutouts are different sizes as well as other parts. Breech cutout on the talon is shown as 27.26mm (1.073″) while it’s shown as being 37.03mm (1.458″) for the condor.
Cocking knob on the talon is shown as 12mm (.472″).
The condor drawings are incomplete, and I’m not familiar enough with the layout to be drawing conclusions with the info on hand.
Maybe some benevolent type with a handy caliper?
Thanks fellas. perhaps all who wish a stem please pm or email me and I can keep track of you.
One of the fellas that donated a valve for me to evaluate and repair brought a great point to my attention. While making the tophat, make it long enough to illiminate the slack in the breech when the cocking knob is latched down.
So I am wanting some more dimensions:
from rear of frame to front edge of frame cut where the knob gets parked
diameter of sleeve on cocking knob
length of breech slide
measure from breech end to cocking knob sleeve.
Thanks fellas.
What I am currently tossing around is a solid ‘stem’ with threads where the tophat sits but at 5/16″ diameter with a loctite permanenet posisitoning of the tophat.
Thinking of how to reduce machining time and waste(chips)
Walter….
Walter,
I have a brand spanking new Selphb valve I would like to fix before I even install it. If you do make any extra stems I would be most grateful to get one. Let me know if you will if this is a possibility.
Thanks very much for all your work on this and other things. I do enjoy reading your posts.
Carl
One big difference is the blod tophat can travel down flush with the valve body. On the selphb valve, the area where the tophat ‘lives’ is more shallow, only allowing the selphb tophat to travel down till about 3mm short of valve body, then it bottoms out. Someone did point this out to me a while back but in my confusion I stated that both tophats had the same travel. They do not.
Does that make any sense at all??!!
Put me down for two stems Walter 😉
Gippetto, Walt, thank you, that is indeed what I was wanting to know.
The tophat on the Selph valves is 0.510″ o.d. and the dim I wanted was the 0.984″ or say 0.100″ the tophat must sit inside the breech.
I plan on making a one piece stem with 0.100″ of travel built into it. IIRC that is what Lang rec’ds and sounds right on to me.
Took the measurements from the valve tonight and have the stem length figured. Kinda rips to lathe down 5/8″ material to 0.510″….. Why was it not made 0.500″ to suit the breech?
Walter….
Walter:
I just made a breech so the numbers are still fresh in my head. On the tophat cutout on the rear of the breech: the cutout is actually a truncated cone with generous rounded corners. At the forward end it is around .500″ diameter and at the back end it is .550″ diam. I just made a form tool to cut it so I wouldn’t have to replicate it each time. The depth of the ‘hat’ from front to back is .120″ Stock hole size through the breech is .312″ which concurs exactly with the Parker O ring manual for a 2-011 ring.
aloha,
walt
Is this of any help? It’s supposed to be a talon. If I understand which measurement you want…2.5mm is .0984″
Nope, don’t have access to a Blod valve so if someone can post a pic and some dimensions and in bloody English inchs!
that would be much appreciated:)
The stem holes are smallish and much smaller than I originally made them.
But smaller holes may work fine as the closing force is increased by the force on teh choked stem. So we will see!
The main closing force with this valve design is the large seal at the tophat.
Gives good closing force for improved efficiency.
Blod owners please report some data.
Have you compared it to the Blod valve? Reports indicate lower FPS so maybe the stem is too small OD & ID.
no troubles.
someone will be able to get the numbers….
Sorry Walt, i’ve been going through all my shooting stuff now that i’m back into shooting again, I have no idea where I put my dial calipers. Knowing my luck ,as soon as I buy one it’ll turn up. I’m sure someone knows the answer. I have a GP gun but w/ US parts in it.
Could do, once I see how much work it is 🙂
Walter….
BTW would like to know the depth of the recess in a stock AF breech for the tophat.
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walter,
hope this helps, Kevin
http://i935.photobucket.com/albums/ad195/diffrnt_68d100/100_0584.jpg
http://i935.photobucket.com/albums/ad195/diffrnt_68d100/100_0590.jpg
http://i935.photobucket.com/albums/ad195/diffrnt_68d100/100_0591.jpg