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Your repairman is correct. The proper replacements are the factory guides purchased from Germany and then lightly filed to fit in your valve casings.

If your horn were an old British built Besson or a Chinese horn with who knows what for valve guides then buying something generic but similar in design and modifying either the guide and/or the valve to make it fit would possibly make more sense. Your horn has a readily available guide designed to work with it. I doubt you would be willing to pay for his time to machine something else to work.

For what it's worth, those little plastic guides cost quite a bit more than you would reasonably expect a nub of plastic to cost. Brace yourself for some mild sticker shock and be gentle in the future.

Call Matt Walters at Dillon Music in NJ. I am pretty sure he keeps them in stock.

Tom,

Your repair technician can also ordered aftermarket delrin guides, made by a company that specializes in band instrument repair tools and supplies in Oregon. They will still need to be fit like the nylon ones, but will last a lot longer.

Hope this helps!

Getting factory parts is generally not a problem but the wait can be quite inconvenient. I've used a variety of plastic screws that are commonly available as temporary replacements. There is little risk in using a plastic screw to get you by even if the threads don't match perfectly. When attempting to remove a broken guides that are broken below the surface of the piston... it's always good to use a left-hand drill. If the drill 'hangs'... the screw will simply back out instead of being driven deeper.

I've found plastic screws at hardware, electronics, and hobbycraft stores that will 'get you by' with minor alterations.

These are easy to come by. They are just the Meinl Weston piston value guides. Talk with Matt at Dillon Music or Albert at Baltimore Brass. They both have them readily available.

Andy makes a good point. The delrin guides are nice.

Dunno what the big deal is.... I had the guides replaced on my 2340 King. The dude took a box of delrin guides down from the shelf. The box was sectioned off into compartments like a fishing tackle box. He just picked through the box until he found the ones he wanted and then put 'em in. Did a little customizing with the file, both on the guide and a little on the casing, until he was happy and I was good to go. Took about 30 min. for all three. Maybe I'm just lucky but it seems it should be that way with all good repair shops.

I had a lot of trouble with fast wear on the plastic valve guides on my PT-6 until I had the slots smoothed down. They would quickly wear down flush with the surface of the valve, which made them extremely difficult to remove. I had a hard time using a drill to remove the plastic screws. Then my repairman showed me his technique of heating a screwdriver and creating a slot by pushing the hot tip into the plastic so it could be unscrewed. Once the new one is installed I use a regular cardboard nail file to sand it to fit.

It doesn't seem like "intelligent design" to have to install these guides into the side of the valve, as it is rather difficult to screw them all the way in without scratching the surface of the piston. I would much prefer to install the guide from the top of the valve. Perhaps there's something I don't know about this. Opinions?

Michael Eastep

mbeastep wrote:.... I would much prefer to install the guide from the top of the valve. Perhaps there's something I don't know about this. Opinions? Michael Eastep

There have been a few designs that employ a pin as a piston guide.... the Conn 'short-action' euphoniums and tubas are one example. Good designs but from a manufacturing/cost point of view... probably more trouble than they are worth.