New Seneca Dragonfly?

[splitbeing]

What an installment! Haven't seen a specifications sheet like this elsewhere, Don. Looking forward to the pump test at 2 turns!

[Nvreloader]

Thanks SB

I believe that the .600+" of dead air not being used is holding back this pumper,
along with the restricted compression containment chamber of 2.170 x .450" diameter,
for 10 to 15 pumps of air?

Then add all the internal valve parts, see post#332, and the center photo,
along with the tapered ends of the valve air release end, it all adds up,
too not much room inside?

I know there is a formula for figuring the CI of the compression cylinder,
I have it saved inside this plastic box, Somewhere?

I am just about ready to make a new valve that is .600" longer and good valve seats and
as large inside diameter as safely possible, to see the results.

I DO NOT LIKE the end of the valve being pounded on by the hammer,
it won't be long before the end is all mashed up and causing problems with the valve stem.
I have got to fix that problem asap, I just have to figure out all the angles, first.

If the wind would have quieted down today (30/40 mph),  I would have finished the 10 pump test to see the results of the 2 turn pump head extension.

Your thoughts and suggestions......
Tia,
Don

[splitbeing]

Don, the food for thought your post provides is also food for a personal Dragonfly fantasy/wish: if the test yields significant enough results, a post simplifying the process of disassembling the rifle in order to make the change from 1 turn to 2 and achieve the results in a manner accessible to novice or intermediate tinkerers.

That's, of course, not just a fantasy but also steps ahead! The test is next and the questions being explored in your dragonfly work are a great read!

[HPP-Mechanic]

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

[Nvreloader]

HPP
I'll make a new top half of the valve, if I have the correct tap/die in metric to fit,
and make the end into a normal poppet valve seal, instead of tapered at both ends.

If Not, I'll make a whole new valve using 11/16 x 16 tpi threads, I know, I the correct tap/die,
and this will allow a good valve seats at both ends and larger inside valve diameter for more volume etc.

I'll try to finish this next 10 pump test with the pump rod head turned out 2 complete turns,
to see the results.

If I figured out the internal volume of the pressure tube correctly for the at 6.300" (now),
of pump stroke depth, I have pretty close to 11.75 Cubic Inch of volume,
so that .600" of dead air space would help more?

Hoping that the larger inside valve volume will make up for the pumps strokes need etc,
I would like to get in the 700 - 750 fps class with the 14 gr Crosmans,
when all the steps/tests are finished..........

Your thoughts and suggestions...........
Thanks,
Don

[Nvreloader]

Guys
Next installment test/information.

I just finished the 1 >10 pumps x 3 each per pump,
pumps were a complete cycle, open then closed arm pump arm, per each pump stroke.
2 complete turns on pump rod head, nothing else changed, with a 11# Flat wire spring,
5" long, .415" O/S Dia, .252" I/S dia, 35 coils, .023" thick Flat wire, coil bound at less than 1.030"

1 pump = 262 fps
2 pumps= 380 fps
3 pumps= 462 fps
4 pumps= 524 fps
5 pumps= 574 fps
6 pumps= 620 fps
7 pumps= 643 fps
8 pumps= 672 fps
9 pumps= 688 fps
10 pumps= 698 fps
No remaining air in valve for any shot.
I went to 15 pumps, but all tests were at or below the 10 pump test for fps,
seemed to stalled out at the 10 pump test?  And I don't know why, yet.

1 complete turn on pump rod, nothing else changed. A 11# Flat wire spring, 5" long,
.415" O/S Dia, .252" I/S dia, 35 coils, .023" thick Flat wire, coil bound at less than 1.030"

1 pump = 288 fps
2 pumps= 321 fps
3 pumps= 354 fps
4 pumps= 561 fps
5 pumps= 597fps
6 pumps= 610fps
7 pumps =616fps
8 pumps =620fps
9 pumps =656fps
10 pumps =688fps
No remaining air in valve for any shot.

A slight increase noted between 1 and 2 turns out on pump head.

Your thoughts and suggestions..........
Tia,
Don

[splitbeing]

The difference between the 1 pump fps reading at 2 vs 1 turn is interesting. Graphing it in my minds eye, the jump between 1 and 2 pumps at 2 turns and the jump between 3 and 4 pumps at 1 turn is also interesting. Are the readings at 3 and 4 pumps correct at 1 turn or should that 5xx be a 4xx on pump 4?

Curious what three sets of pump data for each would tell. Curious if the big jumps would stay at the pump number they are at or change. Has consistency changed with the 2 vs 1 turn?

I'm hooked Don. What are you thinking?

[Nvreloader]

SB
Those are the correct chrono numbers for each step/test on the 1 turn pump head,
and the 2 turn tests..

On the 2 turn head, notice how there seems to be a more gradual increase in fps,
even thou the fps started lower than the 1 turn test, but then stalls out at the 10 pump level,
that is what don't make sense to me.

I need to contact BOB S and see if he can explain this to me, as I am at a loss now.
I know he built a pumper he uses for this grouse hunting that was outstanding in the results.

I am beginning to wonder now........  
I still think it is a combination of the valve and the dead headspace on pumping.

Your thoughts and suggestions......
Tia,
Don

[splitbeing]

I did notice the more gradual increase beginning at pump 2 and overall the graph of the 2 turn data is a cleaner curve.

Regarding the 1 turn data, the big jump in fps between pump 3 and 4 is a bit baffling. I wonder what is going on there and if it would happen in repeated tests.

Back to the 2 turn numbers, 380 fps from 2 pumps and 460 from 3 pumps is pretty impressive stuff.

The 698 fps is more than the stock gun was putting out with that weight pellet. You might be hitting a transfer port bottle neck. If it's not at 80% of the pellet head size, might be worth drilling it open a bit for better breathing. You might then get over 700 and some use from 11 or more pumps.

[Nvreloader]

Sb
Here are the dimensions of all the TP Holes,
and I know they can be opened up to around .170"+" dia, = 70% roughly,
which is the next steps/test coming.
 
BBl TP hole is .134" Dia, = 62% roughly,
Action TP Hole is .134" Dia,
Brass TP is .136" Dia x .295" tall x .356" dia, = 63% roughly,
w/a step on each end that fits into a rubber "O" ring on the action and the valve,
Main valve is 2.520" long x .765" dia, and has a TP hole of .136" Dia.

So this indicates that these TP holes are restricted...........

And the more I shoot it the smoother the pumping is getting,
I have about 200-350 rds thru it now, in between blowing 30+ wind gusts.
Tia,
Don

[Nvreloader]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

[Spacebus]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

Does the gap reduce pump effort? Perhaps the MFG took measures to reduce performance to avoid competing with the PCP on the same platform.

[avator]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

Does the gap reduce pump effort? Perhaps the MFG took measures to reduce performance to avoid competing with the PCP on the same platform.

Exactly my thoughts as I read along but I wasn't sure if we were discussing the Gen I or the DF2.

[2K1TJ]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

Does the gap reduce pump effort? Perhaps the MFG took measures to reduce performance to avoid competing with the PCP on the same platform.

You're probably right. That, and maybe to reduce the stress/breakage on the linkages and such.

[splitbeing]

Increasing the pumping effort is fine with me! I've got the DF I. Helps me build these airguns! [arm muscles flexing] [chuckling]

[avator]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

Does the gap reduce pump effort? Perhaps the MFG took measures to reduce performance to avoid competing with the PCP on the same platform.

Exactly my thoughts as I read along but I wasn't sure if we were discussing the Gen I or the DF2.

I spoke wrong here.. My thoughts were not agreeing with the "competing with the PCP" thing. I personally don't think that was a factor.
The GEN I was notorious for hard pumping. That was specifically the reason I didn't even consider one.
The DF2 attracted me because of what they did to reduce the pumping effort.
I don't know if that head space has anything to do with this reduction in effort but if it does, I would not be interested in eliminating it. I have other options if my main goal is power. If I was after power I would have probably not bought mine in .177.   
I like my DF2 because it's pumper friendly.. among other things.

But it's still fun to read along.

[2K1TJ]

HPP
If and when you get to the tearing down part, can you do this method,
and see what the depth of the pump stroke is on your DF II.

Just barely raise the pump handle before the unlock point,
so you can see the bottom of the slot, "U" section and make a very light scratch
mark on the pump arm.

Then open the pump up fully extended and measure the distance from the scratch mark
to the end of the pump rod head.

When you pull the pump rod parts out, measure from the "U" of the slot of the pressure tube
to the top of the valve.

I am curious of what these length measurements are.

I am looking for first type I of the DF (Parts Donor) to see what those measurements are,
as they had the Rubber ball and other stuff on the end of the pump rod.

I am also curious, WHY didn't they extend the valve length to use/get the most from the pump stroke?
As it is a shame they wasted all the headspace of the pressure tube,
and they could of had a smaller more compact pumper.

Your thoughts and suggestions..........
Tia,
Don

I like where you're going with this.  A longer valve will most likely have more volume, and require more pumps to get to pressure levels than the smaller, stock valve.
Increasing the compression ratio with a longer valve, will hopefully bring the number of pumps needed back down.
Might need the mechanical advantage of the Dragonfly2 linkage to keep the pumping effort down...
When you modify the valve, maybe a longer valve stem would increase the dwell/open time of the valve. May need more time open to use the extra air a longer valve will add...
This is great stuff, and I bought a second (refurb) DF2 in .22 to experiment with...

Does the gap reduce pump effort? Perhaps the MFG took measures to reduce performance to avoid competing with the PCP on the same platform.

Exactly my thoughts as I read along but I wasn't sure if we were discussing the Gen I or the DF2.

I spoke wrong here.. My thoughts were not agreeing with the "competing with the PCP" thing. I personally don't think that was a factor.
The GEN I was notorious for hard pumping. That was specifically the reason I didn't even consider one.
The DF2 attracted me because of what they did to reduce the pumping effort.
I don't know if that head space has anything to do with this reduction in effort but if it does, I would not be interested in eliminating it. I have other options if my main goal is power. If I was after power I would have probably not bought mine in .177.   
I like my DF2 because it's pumper friendly.. among other things.

But it's still fun to read along.

In my experience, the increased pumping effort of the gen 1 was due to the buffer used on the piston rod. Seems like it swelled when compressed and added pumping resistance.  I made a new one, omitting the buffer and pumping effort went down. I'm not the only one that has reported that. In fact I think I may have read it here or somewhere else before I did it myself.

Reminds me...I need to dig it out and chrony it. Idk why I didn't at the time. Seems like somebody had borrowed my chrony maybe, can't remember.

[avator]

Ok, I watched a couple videos on it when it was new and stepped away.

[Nvreloader]

Thanks Guys
Question,
What is the new pump leverage (DF II) as compared to the original DF I rifle?
I think, I remember seeing a chart of the pump differences some where,
I would SWAG it is at least 2 to 1?

If anyone has the GEN 1 model 22 cal, can they please mark and measure how deep the end of the pump rod goes into the pressure tube, and if possible post of good clear photo of the end of the pump rod end.

What is your 10 pump test results, with 14gr ammo?

I still believe that .600+" of dead headspace is doing any good being wasted.
If and when this question is answered, this DF II rifle can be put back as in OEM condition,
if I so want too.

Your thoughts or suggestions.......
Tia,
Don

[Nvreloader]

Hey Guys
After thinking about it, I think that today is going to be the standardization
of all the holes in the air passage route.

I'll use a reamer and go to .140" diameter and deburr when finished,
I don't think I have a .138" diameter reamer, with a 10 pump test,
to follow.

Here are the dimensions of all the air Holes,
BBl hole is .134" Dia, = 62% roughly,
Action Hole is .134" Dia,
Brass TP is .136" Dia = 63% roughly,
Main valve has a hole of .136" Dia.

I missed noting some of the dimensions of the valve and other parts,
and will update with the current information, before I make a new valve
with the maximum inside volume, and good sealing seats,
as tapered sealing seats are not the best options, for a maximum effort here.

Your thoughts or suggestions............
Tia,
Don