Lasonic Function Switch Gear problem SOLVED by Trommelmops

[Superduper]

Obviously, the original setup was a poor design to begin with, is why the originals are all broke. The fellow said his kit were breaking because the people who installed them were unclear how to install them properly. I suspect that if they were printed using a tougher material, they might hold up better. We've had stuff printed using MJF before and those parts are virtually indestructible. Not all 3D printed materials are equal in terms of strength.

 

[playab0yyy]

Obviously, the original setup was a poor design to begin with, is why the originals are all broke. The fellow said his kit were breaking because the people who installed them were unclear how to install them properly. I suspect that if they were printed using a tougher material, they might hold up better. We've had stuff printed using MJF before and those parts are virtually indestructible. Not all 3D printed materials are equal in terms of strength.

He also said there are like 5 different circuit boards all with the same model number that have different specs, which results in his part not fitting/working correctly. That would make going this route of using his part nearly impossible to get right, which puts the focus back on the gear.

 

[playab0yyy]

To go into further detail... So, the problem with the brass one the other guy created isn't that it breaks. See the attached pictures. One picture shows two different knob ends where the plastic gear would go (but the gear is missing from both). The other pictures shows the brass gear he made at the end of one knob with a black set screw sticking out of it. If you look at the picture with the two knob ends, if you look closely at the knob on the left, you'll see the metal kinda flares out at the end. That flaring metal is what kept the plastic hear from sliding off the end of it. If you look at the right knob end in comparison, you'll see it's been shaved down. This is to allow the brass gear to slide on. Otherwise, you wouldn't be able to get the brass gear on with the flared end. This also explains the set screw. Once you slide the brass gear on, you need the set screw to hold it on, otherwise it would just slide off the shaved in. Here's the problem with the brass gear. That set screw will eventually back out, causing the knob to pull out from the gear. That's the problem with the brass gear. However, maybe with some JB Weld or maybe drilling into the knob where the set screw meets it, maybe this could lead to a permanent fix. But with the way people have been using the brass gear with the set screw as-is, it's not a permanent fix and won't last long with usage. Hopefully that all makes sense. The brass gear is definitely a step in the right direction, though.

 

[Superduper]

It looks like you filed it down too far and it’s now tapered. Because of the taper, it will always want to push the gear off with the tapered end.

 

[playab0yyy]

It looks like you filed it down too far and it’s now tapered. Will always want to push the far out with the tapered end.

This is how I got it from WildBill or whatever his name is in here. Regardless, it has to be filed down enough to allow the brass gear to slip on and then there needs to be a way to secure it on (which seems to be the tricky part).

 

[floyd]

The bottom line is until there's better solution this is the only one we got and even that part is scarce so be glad you even got that.

 

[floyd]

I mean it might just be me but I think the man who produced these parts is a f****** genius and I can guarantee you I could do this s*** if I had a hundred years to do it.

 

[playab0yyy]

The bottom line is until there's better solution this is the only one we got and even that part is scarce so be glad you even got that.

Never said I wasn’t glad to have it.

 

[floyd]

Never said I wasn’t glad to have it.

Understood I never said otherwise. You made very valid points. I know what it's like to try to find impossible to find parts. It's like you have to re design everything to make it work lol.

 

[Superduper]

You could use some thread locker on it. Also drilling out the shaft where gear sits you can make a detent to allow the screw to lock into the shaft.

I second this suggestion. Thread locker allows you to disassemble or retighten it if necessary. The reason is that the setscrew is steel whereas the shaft is aluminum. Eventually, the aluminum might get chewed up by the setscrew and the shaft becomes loose once again. If the setscrew was set with JB Weld, then you wouldn't be able to redo it. Also, after tightening the setscrew, you can remove it and see where the mark was, then again, as Floyd suggested, drill a small divot. Combined with thread locker, that gear isn't going anywhere.

 

[playab0yyy]

I second this suggestion. Thread locker allows you to disassemble or retighten it if necessary. The reason is that the setscrew is steel whereas the shaft is aluminum. Eventually, the aluminum might get chewed up by the setscrew and the shaft becomes loose once again. If the setscrew was set with JB Weld, then you wouldn't be able to redo it. Also, after tightening the setscrew, you can remove it and see where the mark was, then again, as Floyd suggested, drill a small divot. Combined with thread locker, that gear isn't going anywhere.

Bingo!

 

[trippy1313]

If he never comes back we could always try 3D printing, but I'd need to model it from somebody's cracked one as long as it's not beat up or distorted or anything. Shapeways offers a bunch of metal options like steel, aluminum and brass. They print by fusing powder together, which results in a somewhat rough, sandblasted texture. I had a small keychain printed in steel earlier this year and the accuracy seems good enough these little gears. Wouldn't look machined, but probably close enough to work

Not sure if I have any original gears you could model a copy of, but I might have an extra trommelmops gear. I'd like it back of course but if it would help, I can try to find it.

 

[caution]

Thanks trippy but I wanted the original gear. I removed my 920 band switch Friday and filed the shaft to get the gear off and model it. There's still a bit of a ridge left on it, so but I'll use some JB or something. Should be fine.

I noticed that the band switch has four positions (SW1/SW2/AM/FM) but the mode switch only has three - I'm assuming that the mode switch's case has the metal stopper in a different spot and the gear is the same as the band switch, but I haven't seen it to know for certain. You can see in the first couple of pics how it can go between four different positions.

The last photo is an overlay of the gear with a silhouette of the 3D model. There are only tiny slivers where they don't line up, so I call it a win. For anyone curious about cost, two of them cost the same as one gear, which is $6 for nylon. I posted an alternate configuration which has some additional materials and different attach points.

There's a bit of space past the shaft that the gear could extend into, I don't see a reason why that would be bad, then it wouldn't be able to slip very far.

 

[playab0yyy]

Thanks trippy but I wanted the original gear. I removed my 920 band switch Friday and filed the shaft to get the gear off and model it. There's still a bit of a ridge left on it, so but I'll use some JB or something. Should be fine.

I noticed that the band switch has four positions (SW1/SW2/AM/FM) but the mode switch only has three - I'm assuming that the mode switch's case has the metal stopper in a different spot and the gear is the same as the band switch, but I haven't seen it to know for certain. You can see in the first couple of pics how it can go between four different positions.

The last photo is an overlay of the gear with a silhouette of the 3D model. There are only tiny slivers where they don't line up, so I call it a win. For anyone curious about cost, two of them cost the same as one gear, which is $6 for nylon. I posted an alternate configuration which has some additional materials and different attach points.

There's a bit of space past the shaft that the gear could extend into, I don't see a reason why that would be bad, then it wouldn't be able to slip very far.

Are you working towards making and selling these? Count me in as a buyer!

 

[ny935]

Thanks trippy but I wanted the original gear. I removed my 920 band switch Friday and filed the shaft to get the gear off and model it. There's still a bit of a ridge left on it, so but I'll use some JB or something. Should be fine.

I noticed that the band switch has four positions (SW1/SW2/AM/FM) but the mode switch only has three - I'm assuming that the mode switch's case has the metal stopper in a different spot and the gear is the same as the band switch, but I haven't seen it to know for certain. You can see in the first couple of pics how it can go between four different positions.

The last photo is an overlay of the gear with a silhouette of the 3D model. There are only tiny slivers where they don't line up, so I call it a win. For anyone curious about cost, two of them cost the same as one gear, which is $6 for nylon. I posted an alternate configuration which has some additional materials and different attach points.

There's a bit of space past the shaft that the gear could extend into, I don't see a reason why that would be bad, then it wouldn't be able to slip very far.

I'll take a few. Have to take my radios down and count up how many I'll need.

 

[caution]

Are you working towards making and selling these? Count me in as a buyer!

They're available right now, Shapeways prints on demand when you order from them.

Unfortunately someone's going to have to be the guinea pig, I'm putting my 920 back together.
There's always a chance it doesn't fit quite right, which means you'll have to order an adjusted version.

It could depend on the type of material chosen also.
For example, nylon may be more forgiving for a snug fit on the shaft - that sort of thing.

 

[docs]

I personally do not believe there is an issue. I've fitted trommelmops gears a number of times, works flawlessly when done right. I can't see how anyone can say it doesn't work "long term" when it hasn't bern long enough to know. Ingenuity is sometimes needed but there is nothing wrong with these gears.
Nice work Eric as per usual.

 

[Superduper]

I personally do not believe there is an issue. I've fitted trommelmops gears a number of times, works flawlessly when done right. I can't see how anyone can say it doesn't work "long term" when it hasn't bern long enough to know. Ingenuity is sometimes needed but there is nothing wrong with these gears.
Nice work Eric as per usual.

I think (playab0yyy)'s issue could partially be attributed to the shaft having been wittled down too far and tapered. A tapered shaft is always going to naturally try to eject what's on the end. Also there is the problem that trommelmops no longer seems to be active here and some users are not able to access his "solution" hence the need for another source.

It could depend on the type of material chosen also.
For example, nylon may be more forgiving for a snug fit on the shaft - that sort of thing.

Eric, I think these gears in plastic are fine, but one issue which I think is a design failure is that unless the gear is locked to the end of the shaft, pulling on the shaft will cause it to pull right out of the gear, at least when I re-watched Chris' video, that's what it looks like. If a gear is still intact but a little crumbly from shrinkage, just trying to pull the knob off could eject the gear from the shaft end. A far better design would've been to have cut a relief around the circumference of the shaft in the appropriate location and locked it with an e-clip or snap ring. Designed like that, the gear wouldn't even need to be glued or mashed because the existing oblong shape should keep it from spinning on the shaft and the locked shaft won't be able to pull out of the gear while caged. One other thought..... while fitting brass push nuts into 3D printed MJF parts, I found that the brass nuts heated up with a soldering iron would push into the hole quite easily. In this same way, a gear with a slightly small hole could be pushed/melted onto the shaft if the shaft is heated up.

 

[baddboybill]

Thanks trippy but I wanted the original gear. I removed my 920 band switch Friday and filed the shaft to get the gear off and model it. There's still a bit of a ridge left on it, so but I'll use some JB or something. Should be fine.

I noticed that the band switch has four positions (SW1/SW2/AM/FM) but the mode switch only has three - I'm assuming that the mode switch's case has the metal stopper in a different spot and the gear is the same as the band switch, but I haven't seen it to know for certain. You can see in the first couple of pics how it can go between four different positions.

The last photo is an overlay of the gear with a silhouette of the 3D model. There are only tiny slivers where they don't line up, so I call it a win. For anyone curious about cost, two of them cost the same as one gear, which is $6 for nylon. I posted an alternate configuration which has some additional materials and different attach points.

There's a bit of space past the shaft that the gear could extend into, I don't see a reason why that would be bad, then it wouldn't be able to slip very far.

Very Cool and totally awesome!!!!Yes the gear is same it just has stopper in different place and I too would be interested in the new one to try out.

 

[Superduper]

Hey guys, I have 2 Trommelmops gears available. Comes with the setscrews. Bought them 6 years ago and still haven't used them. If you can use them, they're yours for what I paid for them. PM me if interested.