Buckeye Brass video on pistons

[bisontuba]

Buckeye Brass video on pistons ...Eastman pistons ..fyi...

[arpthark]

Very informative, but I chuckled at "The bottom is called... the bottom."

[the elephant]

Same.

[bloke]

I'm going to admit that I haven't yet watched the video. I probably will. It's always a risk to post about something without totally being in on the topic, but I'm going to risk it:

Wade knows this because he has a few of them: the three-quarter inch bore Michigan York pistons were considerably longer than most pistons made today. I suspect this may have helped keep them a little bit better aligned with the casings, but I'm not a machinist and nor am I an engineer. One thing about them is that they were remarkably lightweight. Even though they were long, I believe them to be even lighter than the thin wall Meinlschmidt pistons made today as aftermarket pistons with custom porting.

Third hand, I've heard about someone having shown some York pistons to a European piston and casing manufacturer and with that manufacturer telling the person with those pistons that they were extremely impressed with the workmanship, being that they were so lightweight and delicate yet so well made.

[MiBrassFS]

I watched it a few days ago. What struck me was the mention of datums and locating features built into the system, yet they chose to use Yama-copy valve guides which have an extra layer of built-in tolerance slop. The guides were copied so closely right up until the locator pin. It’s daintier. To use a Yamaha guide instead of the Eastman all that’s required is the ever-so-slight enlargement of the locator hole.

Seems to me there was opportunity to use a better guide system. Unless, the intention was to ride the Yamaha supply chain for parts…

[bloke]

Were it that I owned any personal instruments that used Yamaha or Yamaha style guides, I would try to find some old stock original style or some made by Weril that don't have any metal in them.

The only purpose that I see for the metal is to try to defeat the carelessness of the way young scholars put valves back in casings, in other words by trial and error: bang bang bang bang bang found it ( in regards to their method for locating the slot in the valve casings).

Even with the metal, they still end up bending them upwards like a banana, and due to the lack of oiling, the plastic wears off the tip exposing the metal, and then the ferrous metal they use them gouges the slot in the casing. I'm pretty sure that if I had guides such as that on one of my personal instruments that they would last as long as I would.

I'm pretty impressed with the build quality of JP pistons in general (enough so that were I to build a frankentuba, I would be just as happy with their pistons as with German ones - even for my own use), and/but their guides don't have metal inside them and sure enough, young scholars bust the tips off due to the insertion method outlined above. Knowing this, they include an extra set of besides with their large piston instruments... This is a thoughtful strategy, but due to the haphazard way that they are unpacked at the schools, just about 100% of the time when I'm contacted about a broken guide, there's no trace of the package containing the three or four spare guides...

I realize I've delved off into a subtopic (responding to the previous post), but valve guides are sort of like the bracing systems on sousaphone lower mouthpipes: No matter how much extra bolstering or foolproofing, young scholars are going to find a way to defeat it.

[arpthark]

I watched it a few days ago. What struck me was the mention of datums and locating features built into the system, yet they chose to use Yama-copy valve guides which have an extra layer of built-in tolerance slop. The guides were copied so closely right up until the locator pin. It’s daintier. To use a Yamaha guide instead of the Eastman all that’s required is the ever-so-slight enlargement of the locator hole.

Seems to me there was opportunity to use a better guide system. Unless, the intention was to ride the Yamaha supply chain for parts…

This is essentially what Matt Walters intimated to me a few years ago when I bought an Eastman -- that with a different sized hole, I could use Yamaha guides. I never made that modification, but were it time to replace the guides, I'd probably do that.