Disco SSG thread

[David Mccann]

you are correct. the rear screws secure into the rear cap. i positioned the prod brch using the t port "sleeve" to align with disco vlv., then marked and drilled rear holes into my custom rear cap. the forward screws landed in the threaded area of the disco vlv., and would have broken into the threaded cavity inside the vlv., which would result in a serious leak ..those 2 holes had to be moved forward .600 to hit the "meat"  of  the front portion of the disco vlv... hope this helps u to understand      

[David Mccann]

bulldawg: screws are on their way to you... ...cheers

[Buldawg76]

David
Pictures are worth a thousand words and I can see the repositioning of the forward screws and rear screws very clearly and you indeed had some very tedious and nervous machine work with that modification and a job very well done IMO.

I may think out my plans a bit longer before tackling that much machine work as I have access to a big mill and lathe but need to get the parts in hand and measure 5 times to drill once. LOL.

Thanks for the screws and will keep you up to speed on my progress. I am in the middle of a QB build right now so got a few irons in the fire so to speak and also have the parts on their way to complete a 25 Mrod bottled custom 100 fpe gun I have been waiting on a barrel and valve for to get completed.

Mike

[David Mccann]

yea, i know about too many irons , just finished an engine install on a isuzu rodeo, pulling a cyl head today on a corsica, and a brake job on another vehicle and a tune up on another and on it goes........ if you have access to a machine shop, youll have no trouble. i used this;: 

[wll2506]

Just got my screws for the disco, and tried to fix the valve i though i destroyed ... well I fixed it, here is a pic... I will be using 10x32 screws after all ;-   ) I'm very happy I could fix this valve body, the one hole i did not thread I threaded and the one that I though was loos and not usable was the Air hole ... so I was OK, All screws are tight :
http://s20.postimg.org/3zjlxpsal/10x32_in_Valve_smx.jpg

wll

[mooseslayer]

Good to hear. Peace of mind is a great thing. I still inspected my valve and my screws like Lloyd's post suggests, the next time I opened my gun up.

[Rivers3Plinker]

Just a quick mention on the 10-32 screws and modifying for more power and pressure. I followed Bob Sterne's post on disco valve mods. He goes to .25 on the throat. I elected to go slightly less at 15/64 and quickly realized after cleaning the valve body all three of the threaded holes for the retaining screws had daylight in the bottom. Not much - just pin holes at the bottom of the bores but they were through. I plan to finish them off and go right through into the valve body when drill and tap for 10-32. Should I be concerned?
Ordering an extra valve body, Prod hammer weight, Prod gauge block, and Prod gauge today to complete the setup and build internal SSG to go with it.

[David Mccann]

should still work fine. i believe  a leak there would be minimal, and only during the fraction of a second that the shot occurs.

[David Mccann]

how ya been mr moose?? too much going on around here, no time to play much. my belly says it is supper time. hows the temps in canada? 54* here today, a bit nippy to suite me. been making more ssg rods for the rest of the fleet. doing one for leeann's bulk co2  1760 next. we have strings from last summer, so we can compare apples and oranges when we get it tuned. looking forward to testing and tuning it.....cheers

[Buldawg76]

yea, i know about too many irons , just finished an engine install on a isuzu rodeo, pulling a cyl head today on a corsica, and a brake job on another vehicle and a tune up on another and on it goes........ if you have access to a machine shop, youll have no trouble. i used this;: 

David
Yea I have access to a much larger and more stable lathe and mill to do the work on and will get there in time but like you have many iron in the fire at once as well so all good things in time.

Just trying to prioritize at this point is enough on its own and try to do what I can as I get the parts to get each project done. Plus like you working on friends, family and neighbors cars at the same time. Just never enough time in a day. LOL

Mike 

[Buldawg76]

Just got my screws for the disco, and tried to fix the valve i though i destroyed ... well I fixed it, here is a pic... I will be using 10x32 screws after all ;-   ) I'm very happy I could fix this valve body, the one hole i did not thread I threaded and the one that I though was loos and not usable was the Air hole ... so I was OK, All screws are tight :
http://s20.postimg.org/3zjlxpsal/10x32_in_Valve_smx.jpg

wll

Will
Glad you found you could salvage the valve and have the satisfaction of completing the job successfully. Well done.

Mike

[Buldawg76]

Just a quick mention on the 10-32 screws and modifying for more power and pressure. I followed Bob Sterne's post on disco valve mods. He goes to .25 on the throat. I elected to go slightly less at 15/64 and quickly realized after cleaning the valve body all three of the threaded holes for the retaining screws had daylight in the bottom. Not much - just pin holes at the bottom of the bores but they were through. I plan to finish them off and go right through into the valve body when drill and tap for 10-32. Should I be concerned?
Ordering an extra valve body, Prod hammer weight, Prod gauge block, and Prod gauge today to complete the setup and build internal SSG to go with it.

Steve
You should be fine if the heads are snug on the side of the valve and for some extra sealing insurance you can apply some pink Loctite to the screw threads which will seal any gaps in the screw to the threads of the valve but still be easily removed as it is a the lowest strength of Loctite and used for very small screw like 4-40 and below so a 10-32 will come loose with very little effort when desired but will not loosen on its own and the Loctite will seal any air leak past the screws threads completely.

Mike

[dpittman]

My first attempt at internal ssg worked for a while then started to get hard to cock and then not cock at all. I have 1/4-20 bolt going thru hammer with the front of hammer with round pocket and bolt head recessed into it. Dont know what the spring is i picked it up at hardware store. Nylon locknut holding it all together. I cant figure out what is binding. When I take it all apart everything seems smooth. My Disco has a double tube and I would say the ssg theory does work. I pumped gun to 2300 (upgraded valve screws) and started shooting over chrony.  First shot was 761 and started slowly climbing and by shot 53 was up to 802 when it wouldnt cock anymore. Still had probably 1600 psi still in gun. I think the sound is different also. Not as loud. 14.3 gr Crosman pellets btw.

[mooseslayer]

When I went to a heavy spring I noticed a bind. I saw a mark on the hammer from one of the slots so i got my dremel out and chamfered them and then polished both the hammer and the chamber to 1500grit. It is nice and smooth now. Check you hammer to see if any noticable marks where it could be catching.

[Rivers3Plinker]

Just a quick mention on the 10-32 screws and modifying for more power and pressure. I followed Bob Sterne's post on disco valve mods. He goes to .25 on the throat. I elected to go slightly less at 15/64 and quickly realized after cleaning the valve body all three of the threaded holes for the retaining screws had daylight in the bottom. Not much - just pin holes at the bottom of the bores but they were through. I plan to finish them off and go right through into the valve body when drill and tap for 10-32. Should I be concerned?
Ordering an extra valve body, Prod hammer weight, Prod gauge block, and Prod gauge today to complete the setup and build internal SSG to go with it.

Steve
You should be fine if the heads are snug on the side of the valve and for some extra sealing insurance you can apply some pink Loctite to the screw threads which will seal any gaps in the screw to the threads of the valve but still be easily removed as it is a the lowest strength of Loctite and used for very small screw like 4-40 and below so a 10-32 will come loose with very little effort when desired but will not loosen on its own and the Loctite will seal any air leak past the screws threads completely.

Mike

Thanks for the tip Mike. I went with 222 formula which is low strength violet. Is that what you meant? I have 224 blue at home and haven't had much difficulty with removing fasteners using that but this does sound like a better solution. All parts are ordered today. The low 10-32 x 1/4 SHCS, 4K PSI gauge, 1/8NPT high pressure stainless adapter from McMaster and other parts from Crosman including another hammer and valve assembly. The only thing I lack for my internal SSG build will be springs and a bolt which I will probably source locally from the hardware store. I actually do not plan to pressurize the gun much past 2000 psi but want the added safety margin.

[Buldawg76]

Just a quick mention on the 10-32 screws and modifying for more power and pressure. I followed Bob Sterne's post on disco valve mods. He goes to .25 on the throat. I elected to go slightly less at 15/64 and quickly realized after cleaning the valve body all three of the threaded holes for the retaining screws had daylight in the bottom. Not much - just pin holes at the bottom of the bores but they were through. I plan to finish them off and go right through into the valve body when drill and tap for 10-32. Should I be concerned?
Ordering an extra valve body, Prod hammer weight, Prod gauge block, and Prod gauge today to complete the setup and build internal SSG to go with it.

Steve
You should be fine if the heads are snug on the side of the valve and for some extra sealing insurance you can apply some pink Loctite to the screw threads which will seal any gaps in the screw to the threads of the valve but still be easily removed as it is a the lowest strength of Loctite and used for very small screw like 4-40 and below so a 10-32 will come loose with very little effort when desired but will not loosen on its own and the Loctite will seal any air leak past the screws threads completely.

Mike

Thanks for the tip Mike. I went with 222 formula which is low strength violet. Is that what you meant? I have 224 blue at home and haven't had much difficulty with removing fasteners using that but this does sound like a better solution. All parts are ordered today. The low 10-32 x 1/4 SHCS, 4K PSI gauge, 1/8NPT high pressure stainless adapter from McMaster and other parts from Crosman including another hammer and valve assembly. The only thing I lack for my internal SSG build will be springs and a bolt which I will probably source locally from the hardware store. I actually do not plan to pressurize the gun much past 2000 psi but want the added safety margin.

Steve
Yep its Loctite 222 and I am somewhat color blind as I see it as more of a pink than violet so its just a red thing I guess. The blue would work as well but it is not really necessary as there is no forces trying to cause the screws to rotate which would be the only reason to use the blue Loctite versus the violet. You sound like you are well on the way to getting it together soon.

Good luck and have fun tuning it.

Mike

[UCChris]

Hey all. I'm trying to figure out how to make an SSG for my Disco build. I'm wanting to get as many shots as possible with 15.9 grain JSB pellets going 600 fps for a hair under 13 fpe. Problem is, even after reading this whole thread, I can't figure out how to actually make an SSG. Could someone post a step by step tutorial on how they made theirs?

[Buldawg76]

hey folks, whats up. been fiddling with the ssg . here is what i have so far. gotta get some springs.   

Chris
Here is a good picture of what is required to make a simple disco SSG. you need to get a 1/4' x 20 bolt about 2 1/2" long and drill the nose of the hammer out to 1/4" with a recess to allow the turned down bolt head to sit flush in the hammer face. Then use a nylock nut and washer to adjust the spring preload on the bolt to about 1/2" and install inside the spring cavity in the tube making sure the assy has about .050" or more free play with the hammer at the uncocked position so there is no tension on the hammer at rest. You may have to shorten the threaded end of the bolt to gain this clearance. That's it for a simple SSG that requires the end cap to be removed to adjust it or you can get more elaborate and thread the end cap for a adjustment bolt like in page one that mooseslayer shows. it all up to your imagination from here.

Hope this helps.

Or just buy one from here and drop it in and off you go.

http://www.network54.com/Forum/79574/message/1457965393/FS-+Disco+%28etc.%29+drop-in+FreeFlight+Hammer+Mod%27+and+Power+Adjuster+kit-+%2441

Mike

[Rivers3Plinker]

This really gets to the meat of the thread - thanks Mike.
In regards to the internal SSG pics above:
Why use a 1/4-20? There are a lot of ways to skin this cat.
Having a lathe and carbide tools would certainly be a huge advantage machining that hammer weight and bolt like that.
Is there an easier way using say a #10-24 x 2.5"? How would the smaller fastener work in regards to spring selection and would it require a deep counterbore like that?
It might be helpful to know:

• Stroke distance dimensions. What's the distance between the valve stem tip and the end of the tube? I can measure this tonight or tomorrow myself. This helps determine max overall length.
• What's the distance between the sear face and the tip of the valve stem? How far back to pull the hammer until gun can be cocked? This would provide the minimum section of non-thread for the bolt used and the total travel of the weight on the bolt.
• What's generally a good spring strength to use for starters?

This would provide the minimum section of non-threaded for the bolt used and the total travel of the weight on the bolt.
The above design may have been planned out but I more suspect it was shoot from the hip and use what's readily available or on-hand. Much easier to accomplish this sort of creation when you have great tools like a lathe. I am ordering a mini-lathe in the near future just for these sorts of projects and others around the house.

[Dairyboy]

Like said many ways to skin a cat. I have a WAR SSG for my Mrod and although very similar to that design it's much simpler. There's really no need for a counterbore it doesn't need to be flush with the hammer face and spring wise they typically like a longer lighter spring so it's under constant preload on the bolt. Not saying it can't work how David did it because he proved to us it does work great. I'm just saying there are many ways to do it.