Concept makes sense in keeping the shot cycle totally linear. Question is, if it increases performance a good deal, why haven't top level manufacturers (FWB, Air Arms, HW, Diana, Walther etc.)used them in some guns? Those that prefer top shelf stuff would pay extra for the feature...At least I would. How many modern compression tubes from those makers (Top tier) need honing -with or without buttons. Of course the buttons would need to be sized to the tube. Will the buttons induce much drag on the piston? I don't have a drill press but lots of people I know do. I see ARH (JM) sells glue on variants but I'd be concerned that one could become dislodged, say in a magnum. That would be counter productive.
Not knowing the first thing about buttoning, what are you guys' thoughts?
Here are a couple personal comments/opinions:
"Buttoning Springer Pistons. Is it Worth it? "
Depends on the gun. I used to get rather sloppy "piston to receiver fit" with the HW springers I bought because the receiver IDs were "excessively honed" before assembling creating a "belled receiver ID" at the transfer port end when the operator "fell asleep" honing. Also, the piston themselves weren't very consistent and I measured one with a piston skirt that varied about .010 in "ovality". The latest HW springer I bought (a HW95) had a really good receiver ID and the piston fit nicely enough that I only polished the skirt a bit before re-installing..........
Later model factory HW95 receiver internal finish compared to my older Beeman R9 factory finish...........
Here is the later HW95 piston before and after polishing the skirt a bit...............
All my HW springer pistons have the factory piston seal replaced with a home made oring sealed piston cap which does requires a more consistent receiver to piston seal fit than a factory seal so I hone the receiver ID with a home made hone to reduce "internal restrictions"...........
"why haven't top level manufacturers (FWB, Air Arms, HW, Diana, Walther etc.)used them in some guns?"
IMHO.......extra cost to manufacture and the fact that with factory "parachute seals" can handle any variations in receiver tube geometry so "buttons" aren't really necessary. Actually, The "piston seal end" of the piston doesn't "see" a lot of sideways force. The "piston skirt end" of the piston "sees" the force from the cocking shoe. Also the HW and Diana used "hardened piston skirts" and the receiver tube is unhardened so the "dissimilar metals" won't gall when "properly lubricated". Actually, Air Arms does include "plastic bearings" for the TX200 type piston............
"How many modern compression tubes from those makers (Top tier) need honing"
Guess that would depend on the tubes themselves but It does seem that the honing process prepares the surface by removing "mill scale etc". Years ago it was believed that "honing" created the necessary cross hatching to help the distribution of lubes and I'm sure that some still do. LOL....I remember seeing pics of compression tubes and receivers that had visible "cross hatch scratches" from the honing process. I'm thinking that this practice had it's roots in the fact that automobile engine cylinders were cross hatched s the new piston rings would seat properly when "wearing in" and some think that "rubber" seals need "wearing in".
I used an old leather sealed HW35 for a couple decades and noticed that the leather seal had polished the receiver ID "bright & shiny" yet the gun functioned perfectly till it was sold a couple decades later. This made me think the cross hatching really wasn't necessary so when I started using oring sealed piston caps in my HW springers I would first "sweeten" the receiver ID by honing (using a home made hone) and finishing up the hone with oiled 500 grit wet-or-dry abrasive, then buffing out the honed surface with 0000 steel wool. This surface worked well with my oring seals and when I bought my HW95 a couple years ago I noticed that the factory receiver finish was identical to my home honed finish. Again, here is the pic of the factory HW95 receiver ID..........
As a side note, the high end FWB300 match gun piston is sealed with an automotive style metal piston seal so I'm betting that the compression tube has much tighter tolerances than the "rubber sealed piston guns"...............
"Will the buttons induce much drag on the piston?"
No, unless they are tight. They simply "go along with the ride" when the piston is "released". Their only purpose is to 'center the piston" and break "metal to metal contact".
"I don't have a drill press but lots of people I know do."
As mentioned, HW and Diana piston skirts are hardened (actually case hardened) so they are difficult to drill without carbide bits. Whenever I needed to add buttons I used mu small milling machine and a carbide end mill to make a recess.
"glue on variants but I'd be concerned that one could become dislodged,"
Yep, can happen and a while back I received a springer where "glue on buttons" did "let loose" and were "floating around" in the receiver. Bad glue, improper installation, I don't have a clue. If you look at the pic you'll see where the surface under the button was "properly 'roughened up" but the button "let go" anyway..........
For my "button jobs" I always mill a 1/4" diameter recess in the piston skirt (again, using a carbide end mill). If the glue fails (I use SuperGlue) the button is held captive between the piston and seat of the recess so it can't "float around"............
Bottom line, I don't mess with buttoning unless the piston is a sloppy fit with the receiver.
IIRC, Jim used to machine (probably just using an end mill) depressions into the piston body, install buttons, and turn piston on a lathe to size to the individual tube. Regarding the glue-on buttons, his ARH site said: "I put 6 buttons on a .22 R1 and gave up looking for wear after 20K shots. So they last really a long time or forever." Hmm . . .
Concept makes sense in keeping the shot cycle totally linear. Question is, if it increases performance a good deal, why haven't top level manufacturers (FWB, Air Arms, HW, Diana, Walther etc.)used them in some guns? Those that prefer top shelf stuff would pay extra for the feature...At least I would. How many modern compression tubes from those makers (Top tier) need honing -with or without buttons. Of course the buttons would need to be sized to the tube. Will the buttons induce much drag on the piston? I don't have a drill press but lots of people I know do. I see ARH (JM) sells glue on variants but I'd be concerned that one could become dislodged, say in a magnum. That would be counter productive.
Not knowing the first thing about buttoning, what are you guys' thoughts?
Air Arms DOES do it on the piston in the TX200, with synthetic rings.
They did the same with their now-defunct, but much-coveted, Pro Elite model.
Check out my reply to your question about about polishing springer pistons, for more comments about buttons and rings.
Thank you for the wonderful write up and the pics to follow along with....allowed me to feel like complete interaction with an author.
I need to buy an ID gage for cylinder. What do you use if I may ask? I would feel warm and fuzzy knowing I don't have any tubes too far out. With the tools required, I may prefer a tuner do any button procedures, I believe. Hopefully I didn't get the sleepy honer!
I hadn't thought about the cocking stroke regarding the skirt. Seems to make sense to smooth that out a little, and maybe "knock down" the perimeter edge of the piston skirt bottom OD a little bit (perhaps even the ID of that for the spring interaction?). The only thing I've honed by hand for cross hatching was the cylinders of a Ford Pinto years ago LOL. Glad your latest HW95 had a decent fit.
Interesting that AA builds the TX200 (& PS from Ed's reply below). Always read great things about those AA's straight from the box. Also interesting that FWB uses a metal ring. I too would bet those tubes have tight tolerances.
Thank you for the wonderful write up and the pics to follow along with....allowed me to feel like complete interaction with an author.
I need to buy an ID gage for cylinder. What do you use if I may ask? I would feel warm and fuzzy knowing I don't have any tubes too far out. With the tools required, I may prefer a tuner do any button procedures, I believe. Hopefully I didn't get the sleepy honer!
I hadn't thought about the cocking stroke regarding the skirt. Seems to make sense to smooth that out a little, and maybe "knock down" the perimeter edge of the piston skirt bottom OD a little bit (perhaps even the ID of that for the spring interaction?). The only thing I've honed by hand for cross hatching was the cylinders of a Ford Pinto years ago LOL. Glad your latest HW95 had a decent fit.
Interesting that AA builds the TX200 (& PS from Ed's reply below). Always read great things about those AA's straight from the box. Also interesting that FWB uses a metal ring. I too would bet those tubes have tight tolerances.
"buy an ID gage for cylinder. What do you use if I may ask?
I fit my HW pistons with an oring sealed piston cap and the fit of the oring to the receiver is much more critical than the fit of a factory piston seal. I found that the receivers of my HW springers are too inconsistent to be measured so I made a "go/no-go gage" by machining a disk to be slid into the receiver. If the "gage" slides from "end to end" without hanging I consider the receiver to be OK. If the "gage" slides freely but gets tight along the tube I hone the constriction till the "gage" slides past the constriction. If the receiver tube has been "belled toward the transfer port" I consider the receiver tube to be incompatible with an oring seal. Here are a pics of my "go/no-go gage"..........
Here is a pic of my "hone"...........
@jim-bentley
you are an accomplished machinist
I'd say so too, I won't be able to do what Ed can do as I'm not in his league, however there is enough information presented here to "keep me in the black" and "Get my Mind Right" (see Cool Hand Luke ? ). For that I'm most grateful to you all.