Valves slow on upstroke

beetleklee · Posted: Wed Mar 27, 2024 5:42 pm Post subject:

Sorry just catching up, I've been busy with work.

I replaced the old metal valve guides with replacement plastic ones. Hard to say if this has improved anything, I thought it did at first.

When I just fiddle with the valves, I very, very rarely get any slow upstrokes. It seems to be mostly when I play the horn.

I checked the valve compression by taking the slides out and plugging up where the air comes out. I had to blow with a lot of pressure, and heard a small amount of air, but from what I read this is normal? I still have to apply a lot of air pressure to get that. Also the slides do "pop!" when I take them out and have some resistance if the valves aren't down.

The 1st and 2nd valve mostly work perfect with Clean Stroke valve wash. The 3rd works better but it still hangs up on longer notes sometimes.

I don't notice any side to side play on the valves. If they are worn, which it looks like a bit...it isn't enough to be super loose. The stems don't look bent.

Here's the 3rd valve, with the brown wear at the bottom:

The 2nd and 1st valve look similar. No brown wear, but shiny streaks here and there.

The lighting in the photos makes the bottom of the valves look bent, but they are not.

My last resort will be to try the alcohol soak but I am not going to do anything like lapping. If that doesn't work...to a tech it goes.
_________________
1970s King Silver Flair 1055T
1970s Holton T602
1950s Getzen Super Deluxe Cornet
1915 Conn 80A Cornet

etc-etc · Heavyweight Member Joined: 19 Jan 2008 Posts: 6191

Ask the tech to measure the casing IDs (and also piston ODs) at the top, middle and the bottom. Photos suggest an "hourglass" wear pattern where shiny spots are the locations of concentrated abrasion. As long as you can source oversized pistons to match, casings can be re-finished to a larger ID with a clean cylindrical shape.

Ronnman · Posted: Wed Mar 27, 2024 8:10 pm Post subject: P

beetleklee - I would get some wet/dry 3000 grit sand paper, cut some pieces to slightly greater than the valve section and wide enough to wrap around the circumference of the valve. Disassemble the valve and just use the button. Wet the sand paper and add a few drops of Dawn dishwashing detergent to the sandpaper and the valve. Form the sand paper around the valve body and ONLY work the valve up and down, (just like the normal valve motion). Work the bottom of the valve where you see the staining until it is gone. Then rinse the valve and sandpaper off. You can most likely reuse the sandpaper for another valve as needed. Rinse the valve with hot water throughly and the then with cold water. Dry the valve completely including blowing out the internal vent passage. Clean the valve casing with 91% isopropyl alcohol. Reassemble the valve, add oil and install the valve. Operate the valve for about 3 minutes. Remove and wipe the valve off, looking for a slightly grey residue. Do this until the wiping comes clean.

There will be some who would not do this, but 3000 grit wet/dry sandpaper is barely abrasive. When wet with detergent/water it should be just the ticket to get the stains off. If it still sticks/drags you could polish the stained area with Flitz polish using up/down strokes again. Just throughly clean the valve with the alcohol, and then oil, before reinstalling. I prefer this method to the Lava soap suds.

I did this procedure this week to one of my horns that started the untimely slow upstroke/sticking. I just practiced two hours tonight with no valve sticking issues.
Ron
_________________
Martin Committee #2 1954
Leblanc “Al Hirt” Model 1966
Olds Custom Crafted Ultra Sonic 1974
Edwards Gen II 2014

etc-etc · Heavyweight Member Joined: 19 Jan 2008 Posts: 6191

Before using anything abrasive, consider this approach:

beetleklee · Posted: Wed Mar 27, 2024 9:41 pm Post subject:

Eh I don't trust myself to do anything to the valves like that. I'll try and clean with alcohol and then take it to a tech if that doesn't work.

It's possible my fingering style is different than the old owner, but to be fair, the sticking doesn't happen all the time and it tends to only happen when I play the horn. Last night after replacing the valve guides, I was just fiddling with the valves for 30 minutes, not blowing the horn, and I had zero issues. I thought I had fixed it. I would hold them all down as if playing long tones, bring 'em back up, no sticking. But when I add air, sometimes they're slow to come up. The first and second work fine with Clean Stroke, the third is a bit better but not perfect enough. It makes playing anything involving the third valve a pain in the butt.

I arch my fingers and press straight down, I even tried playing from different angles, to see if they were broken in a certain way, but still had the sticking issues.

I never play with food in my mouth. I actually have Invisalign so I'm constantly brushing and flossing multiple times a day. I clean my horns once a month too.
_________________
1970s King Silver Flair 1055T
1970s Holton T602
1950s Getzen Super Deluxe Cornet
1915 Conn 80A Cornet

Halflip · Posted: Thu Mar 28, 2024 3:18 am Post subject:

Andy Cooper · Posted: Thu Mar 28, 2024 6:46 am Post subject:

Take a flashlight and check the inside of the 3rd valve casing. Do you see the same dis-colorization ?

If so, read my previous comment on using vinegar. I recommend a wad of paper towel soaked in vinegar for the casing and wrapping the bottom of the piston with paper towel soaked in vinegar. Keep them wet with vinegar for several hours. Why subject the entire horn to an acid soak when only a small portion has a problem.

When the discoloration is gone it should show kind of a light gray matte finish on the piston. I would do a light lap of the valve -I've done it before and know my limitations. Instead, you should consider just making repeated applications of either Denis Wick (which contains Teflon) or one of the Graphene based valve oils. I've had good results with both. The key is repeated applications.