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Re: Venting rotary valve?
Posted: Thu Dec 24, 2020 9:14 pm
by djwpe
Doc wrote: ↑Mon Dec 21, 2020 8:42 am
I have vented two tubas, and, despite being VERY apprehensive, it worked out just fine. I followed instructions and took my time. The biggest pain was getting the hole started without the bit sliding around and gouging all the lacquer. Patience is your friend. Everything else went according to plan. I haven't yet vented the Hagen, but I need to bite the bullet and get it over with.
Your Hagen wasn’t factory vented? Mine was...
Don
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 3:39 am
by pjv
One of the piston tubas I rarely use is vented at the bottom of the piston itself (not the casing). The air passes through the (hollow) valve and channels out the bottom, where it enters or exits the casing through the bottom valve cap.
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 5:11 am
by Doc
djwpe wrote: ↑Thu Dec 24, 2020 9:14 pm
Your Hagen wasn’t factory vented? Mine was...
Don
I assumed it would be, but no such luck .
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 8:31 am
by bloke
Do any B-flat players pull slides...??
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 8:51 am
by jonesbrass
pjv wrote:One of the piston tubas I rarely use is vented at the bottom of the piston itself (not the casing). The air passes through the (hollow) valve and channels out the bottom, where it enters or exits the casing through the bottom valve cap.
From what I’ve seen, pistons are vented that way. No need to modify the casing. I’m going to get some of my pistons vented after the new year. It will really help on my 6/4 CC.
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 10:03 am
by Doc
Re: Venting rotary valve?
Posted: Fri Dec 25, 2020 10:33 am
by Rick Denney
You can mount the drill bit in the handle for a watchmaker’s screwdriver (the kind that has replaceable bits and a rotating finger pad at the top) and drill the hole by hand very accurately, and very close to the slide tubes. This works for pistons, too.
I have cut slots in pistons using a Dremel cutoff wheel, and that works, too. I did that on my 621 F and it worked perfectly. But alignment is crucial. And worn pistons or rotors struggle enough to avoid leakage, so for those I just say no. Matt Walters vented the valves on the York Master, and Bloke vented them on the Holton. Both made a smaller hole than I would have, and smaller than the factory vent in the first valve of my Eastman.
I need to vent the first valve on my Hirsbrunner. The staff C is flat, as usual, and the first slide is (beautifully) made to be easily adjusted. But without the vent, the pops are a problem. I’ve been using the fourth valve for that note, too.
Rick “more fearful of screwing up with increased age-related wisdom” Denney
Follow-up Re: Venting rotary valve?
Posted: Mon Feb 01, 2021 11:12 pm
by Jperry1466
Finally got this project done after coming down with Covid-19. Fortunately, I had a very mild case with low grade fever, loss of apetite, and extreme lethargy for 3-4 days. The aftermath was worse than the virus, getting tired easily. (I had to rest after unloading the dishwasher, for crying out loud.)
I took all the advice and pics from here to my repairman who said "never trust anything from a forum" then called Miraphone to get instructions. As you can see, the pic looks exactly like the pics that were posted here on the forum. But I like this repairman, so I kept my mouth shut. The hole isn't the neatest-looking, but it works great. The pop when moving the 1st slide is gone, and the horn plays as well as I had hoped. Another benefit was that the repairman took note of my small, arthritic hands and moved the valve spatulas closer together. I am extremely happy with the final product. Thanks, guys for all the good info.
Re: Venting rotary valve?
Posted: Tue Feb 02, 2021 1:50 pm
by jonesbrass
Jperry1466 wrote:The pop when moving the 1st slide is gone, and the horn plays as well as I had hoped. Another benefit was that the repairman took note of my small, arthritic hands and moved the valve spatulas closer together. I am extremely happy with the final product.
Who doesn’t love a happy ending? Glad you are over the ‘rona, too.
Re: Venting rotary valve?
Posted: Tue Feb 02, 2021 2:14 pm
by bloke
As - 99% of the time - rotor casings (or - ref: Progressive Ins. Co - "Rotaur") are mounted on people's instruments, I use 12-inch-long 1/16" diameter (choose your own diameter) "aircraft" bits.
I could re-sharpen them, but I buy a gob at a time, and toss them when they stop cutting as quickly.
I did the "3 vertically-aligned holes" thing decades ago, when I installed a very long-throw 5th valve (right hand) trigger on my F-tuba - to microtune 5-6-4 "low A", and also to offer me a 5-6-1-2-3-4 2nd partial (matching timbre / easier to focus) "low F".
lucky me: Those two pitches are the only ones which involve any slide-moving on that instrument...but maybe (??) that's why others wince, when I'm playing ensemble pieces with them.
Arguments can be offered up for drilling those holes a bit off-center vertically (to get them farther away from the ports), as well as putting them a bit off-center horizontally (so that a subtle paddle-touch (prior to playing a passage) PRE-equalizes the air pressure. I'll let others (who also enjoy "lacquer vs. silver" and "globby vs. non-globby mouthpieces") argue over those preferences, but (unlike those two parenthetical topics) there might (??) actually be purposes for those off-center venting strategies...(??)
It's also a good idea to take the rotor out, because the tubing knuckles (brazed in to the rotors) are not always centered on the spacing between the knuckles...particularly not (sometimes) with jimbo.
You can get them for a couple dollars less, if you buy a package of several, but here's one that can be bought at "laagge oohange - YET 'currently out of stock'...but you'll find them elsewhere.".
https://www.homedepot.com/p/Drill-Ameri ... /305284245
Re: Venting rotary valve?
Posted: Tue Feb 02, 2021 6:02 pm
by Doc
Re: Venting rotary valve?
Posted: Tue Feb 02, 2021 7:12 pm
by bloke
“Hagen“ sounds like it should be the name of some creamy spread made from some exotic mixture of nuts with lots of sugar.
Re: Venting rotary valve?
Posted: Wed Feb 03, 2021 8:06 am
by Three Valves
It will always remind me of Nina Hagen.
Re: Venting rotary valve?
Posted: Sat Feb 13, 2021 6:01 pm
by grayax
bloke wrote: ↑Fri Dec 25, 2020 8:31 am
Do any B-flat players pull slides...??
Once I get done modifying and rebuilding by 1241, I probably will need to down in the pedal register (adding a fifth valve).