Metal links for rotors are not the be-all/end-all.

[bloke]

They are great (assuming no maintenance) - for perhaps five years...

...and then (unless someone [ hasb]very[/b] regularly lubricated them with thick out (I use 30W) they will begin to click.

My Miraphone ones are stll quiet...I oil them every time I play. The original owner (probably) used the instrument for 6 months "worth" of time, and I've used it for maybe a year's "worth" of time.

There are some on a Bach "Strad" F-attachment trombone (in for playing slide best-I-can-possibly-do) repairs.

Yes, the trigger's hinge screw clicks, and the rotor body itself clicks, but the two metal Minibal-like links ALSO click.
It's roughly a 5 to 6 years old trombone belonging to a college student.

My ugly/clunky/inarguably-amateurish-in-appearance Dubro adjustable plastic links (on my 42-year-old F tuba) are about 35 years old, and are "studio-quiet".

[LeMark]

I have a set of dubro on order. They should be an improvement than the Chinese minibal that are on the Packer. They SAY minibal, but they can't possibly be the real deal.

Also replacing the connecting rods

[jtm]

What's the right applicator for getting heavy oil or grease in those linkage sockets? And where can a civilian buy them?

[bloke]

Some people believe those are counterfeit...maybe they are...(??)

I've had ones - bought straight from the German maker - here which are the same as the JP ones (the ALUMINUM-BODY/lightweight ones which are - likely - rarely ordered).

The aluminum ones - in particular - make clicking noises sooner, as their frames are softer metal.

Side-by-side, the JP (aluminum) ones and the ordered-from-Minibal (aluminum) ones look just the same...and I looked pretty closely - due to having seen the accusation (just above) made before.

Either than are really good counterfeits or they're not.

Were I to replace aluminum-bodied Minibal links (whether genuine or counterfeit) with new ones, I would replace them with REGULAR STEEL-FRAMED ones.

[bloke]

What's the right applicator for getting heavy oil or grease in those linkage sockets? And where can a civilian buy them?

The articulating surfaces in those links are so little (square inches of contact area - wise) that there's probably almost nothing (commonly available) that would be considered "too thick".

I have 30W handy (which I use to lubricate rotor stems) and 30W EASILY runs in those links (due to not being a "grease") do that's what I use.

STP Oil Treatment (the consistency of honey...ie. considerably more viscous than 30W) would surely be great...I'd guess that - after a few minutes - it would work its way around to all articulating surfaces.

I use a needle oiler to put drops of 30W here-and-there on misc. bearing surfaces...I'm thinking that STP Oil Treatment would require some really serious "convincing" to be coaxed through a needle oiler. With STP, I'd probably use a finger - followed up with a paper towel (for the finger).

[bort2.0]

I have a set of dubro on order. They should be an improvement than the Chinese minimal that are on the Packer. They SAY minibal, but they can't possibly be the real deal.

Also replacing the connecting rods

Sometimes Autocorrect has really got your back.

[BRS]

.

[bloke]

A lot of the Chinese instruments that sport “Minibal” hardware I see do have the name brand stuff. Problem is they aren’t the nickel silver and stainless version. They are the aluminum version that Seibold markets for models, not musical instruments. Seibold makes several different sizes as well as different grades. They say Minibal, but they are they aren’t what we’re expecting. The required forces are much higher on a tuba than they are on a model car, so the aluminum version wears and gets sloppy pretty quickly.

They’re cheaper ‘cause they’re cheaper. There’s Minibal and then there’s Minibal.

I appreciate the back-up, and/but those (steel) used on Bach Stradivarius instruments (haven't peered at them close enough to see if they are brand-stamped) - again - click, after they're a few years old.

The Miraphone ones are the small Minibal size, thus (though steel) I completely expect them to wear faster...thus: generous/regular lubrication.
The (disastrous black plastic) ones that Miraphone used in the not-too-distant past (based on appearance) were - I"m guessing - also made by Minibal. Their profile was just about identical to the steel ones they currently use.

bloke "If only Dubro plastic/adjustable looked 'expensive', and ONLY IF tuba players weren't being completely disingenuous when claiming, 'I only care about the sound'. "

[BRS]

.

[bloke]

I don't have one of those big expensive magnifying viewers, but I ended up with a whole bunch of spare JP linkage action arms. I use them when - serendipitously - they happen to be bent the way they need to be for another tuba and also happen to be the right length. I've examined their threads with a magnifying glass in good light, and they seem to be well-cut. If they're getting loose on those aluminum links, I would suspect the soft aluminum and not the action arms, and I guess I'm directing this towards Mark.

It's pretty easy to buy some steel Minibal links - that are the same large size - and just swap them out. Again, I buy them directly from the maker. People who import them and sell them over here mark them up to where they're quite expensive.

[LeMark]

On my first valve, the adjusting nut, for lack of a better word spends freely. Unless the action rod is spun out so much from the linkage that it finds some threads to grab onto.

[bloke]

I have noticed that some of those knurled lock nuts aren't so hot on some of the Chinese tubas, but I haven't seen it on these in particular. I'm glad to see it reported so I can mention it. Of course I can't really examine female threads on knurled nuts with a magnifying glass as easily as I can male threads on action ams.

I would like to see the parts between the levers and the rotor stems stepped up in grade just a bit. I've never had a gripe with any of their pistons or rotors. Their rotors are super close-fitting - which is really cool, but - just as I've discussed in other threads, tubas collect lime from being played, and if really close-fitting rotors are not going to stick, they need to be oiled every time they're played discourage lime from building up on them and their casings. If really close fitting rotors like these aren't oiled daily, they're going to start to catch on lime deposits, and if they are left for a couple of weeks without having been oiled the last time they were put away, they're likely to get what I call "spit stuck".


The horn maker, McCracken - who seemed to have an association with the King Factory in Cleveland, built horns with really really close tolerance rotors as well. It was all the same stuff. They needed to be kept clean and oiled, and lime-free.
(My Miraphone 98 rotors are very clean and fit very well. I don't think they fit quite as closely as those JP rotors usually do, but the Miraphone rotors fit quite closely. If I just pick that tuba up and play it - after having oiled and played it "yesterday" - the valves are very good, but if I take a moment to put some really thin oil down through them and slosh it around, the valves are really great. I'm not talking about Mark, but I'm talking about they're being some sort of general belief that rotors don't need to be oiled very often. Humbug.

I have some of those nuts, Mark, and say the word and I'll send you a couple of them. If only one of them features sloppy threads, if you are aluminum frame links are clicking, again just swapping them out for a steel frame ones from Germany should address those issues. I also still think that you'd be happier with nickel silver center screws - vs. the steel ones, as nickel silver will stretch as the screw becomes tight and sort of act as their own lock screws. I can't get the Chinese to make center screws out of nickel silver, but Miraphone center screws are the same thread as the Chinese ones which are made of steel.) The Chinese are going to do what they're going to do.

[bloke]

I don't think the nuts are stripped because they will catch on threads at the end of the action rod, but not in the part I wish it would tighten up.

I have all the parts to replace the linkage., so right now that's the plan. Stainless steel tubing, 3mm threaded rod, and dubro links

[bloke]

go Dubro!

[Rick Denney]

I need to replace the Minibal ends on my Hirsbrunner. If someone wants to sell me a set, holler. I’ll measure up what I have.

The linkages on which I installed Du-Bro links 35-36 years ago are still perfect. That includes a Miraphone 186 C and a Bb 4/4 Rudi, about which I have current knowledge. Others have moved along to other homes and I’ve lost touch, but if they were replaced, I am confident it was not for functional reasons.

Rick “will keep the Minibal links on the Hirsbrunner if another set can be sourced, just for appearance and value retention” Denney