GTA
All Springer/NP/PCP Air Gun Discussion General => Machine Shop Talk & AG Parts Machining => Share Your Simple Home Projects (TRICKS-N-TIPS) => Topic started by: Oldgringo on May 11, 2019, 04:17:38 PM
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I've seen reference to homemade sleeves that dampen twang. Are there pictures, measurements anywhere that an old goat can learn from and apply to a couple of his twangers? I have plenty of Diet Tonic Water bottles for material source. ;)
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I tend to like this one. I start with a 3" X 5" square of plastic. https://www.youtube.com/watch?v=q4H3THAzhrA (https://www.youtube.com/watch?v=q4H3THAzhrA)
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Thomas,
Thanks for sharing.
ar
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Thanks, Thomas. That's what I was looking for. I didn't quite catch the purpose of the cutouts on the inside end? Is that to keep the sleeve from sliding out? It seems I recall a comment somewhere about using some stickum of some sort to hold the sleeve in place?
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The cutouts are so the spring will hold the sleeve in place. I use a variety of materials for my sleeves based on thickness of the material. I use different two liter bottles, vinyl cutting board, and any other non metallic thin plastics/vinyl's. I cut it to the length of the inside of the piston plus about 3/16" and cut lengthwise so the ends of the sleeve just touch each other when installed in the piston. I then place the sleeve in a vice so that just the 3/16"excess length in clamped and bend the sleeve to a 90 degree angle to the length of the sleeve. Then I have an pair of pinking shears ( the kind seamstress use to cut material with a zigzag end ) and cut the 3/16" so its a zigzag edge so when you coil the sleeve up to put in the piston it will coil without the edge binding the sleeve. Then use some light grease and a steel washer between the sleeve and inside end of the piston to keep the sleeve from sliding out of the piston when fired. The steel washer prevent spring rotation from tearing the zigzag end of the sleeve by allowing the spring to rotate freely against the washer.
Hope this helps.
Mike
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Yes the tabs are folded then the sleeve with the tabs are inserted head first into the piston.. The spring is inserted and keeps the tabbed sleeve from moving.. I used a cheap plastic cutting board and it works well..
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You cut the tips off the tabs to allow room for the latching rod to go through. I like to use the tops off of one pound salad mix tubs.
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You cut the tips off the tabs to allow room for the latching rod to go through. I like to use the tops off of one pound salad mix tubs.
Like the stuff you get at your local IGA?
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By only making the folded portion of the sleeve 3/16" in length negates the need to cut the tips off since there is till enough clearance for the piston latch rod to pass thru the front of the sleeve and not bunch up or bind the sleeve. If the piston latches around the outer diameter its not as critical for the length of the folded portion.
Mike
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Hi ,,i use the small metal coffee jars (stainless i think) and 0.25mm ptfe sheet,, the ptfe is amazing it's 100% better than a plastic bottle it makes cocking the gun silky smooth i couldn't believe it made so much difference compared to metal or plastic
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stickum .... heavy TAR between shim and inner wall of piston. No tabs required.
DON'T use TAR on the spring, but do use a light bodied lube/grease
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Worked wonders on my Diana 34P.
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Since converting my TX to one of Tony Leach's 22mm skirtless piston kits I have been using STP oil in my springer's. It is the lube he recommends for his kits and used very sparingly on the piston and spring/guides. His piston is a HW style piston seal with an o ring backup seal. It is critical that no STP is placed ahead of the piston seal face in the chamber. so the piston is started into the chamber then the STP is sparingly applied to the o ring and delrin guide rings while working the piston in and out of the chamber to spread a thin layer of STP thru the chamber. You can feel when it has been spread around in the chamber as the piston will become slippery smooth when pushing in and out. Then a light coating on the spring and guides is all that is needed. My TX is shooting AA 7.87s at 815 to 819 fps consistently with a 4 fps ES or less with several identical fps numbers in a row. The SD is 1.2% over 30 shots.
I have used it in a retune of my 124 from 14 to 12 fpe with the same results. It will diesel if it gets in front of piston seal so it is imperative the you start with a dry lube free chamber before the piston is inserted in the chamber so to eliminate any chance of the STP getting in front of the seal face. I am liking it a lot and one bottle will last a lifetime.
I use tabs on my sleeves more for piece of mind than having to wonder if its still in its proper place after thousands of shots. Just my personnel preference of construction.
Just my .2 cents.
Mike