New "TSDZ2 Torque Sensor Central Motor"

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Djoze   10 µW

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Djoze » Aug 29 2017 2:27pm

Since yesterday, my TSDZ2 started to be noiser, a lot more noiser. Because it increased gradually, it took me some time to consider it as a problem. This morning, I was louder than a scooter: https://youtu.be/cWJxAJMwrGI

I extracted every single part of the motor for nothing, the noise was coming from a vibration with the frame. I inserted a piece of inner tube between the frame and the rear attachment of the engine, silence came back. I took advantage of the dismantling of the engine to lubricate it and to check the nylon sprocket. Everything is fine and smooth after 200km (125 miles) and 80% of the time spent with maximum assistance.

Regarding the speed accuracy, with my 700x23c wheels, "28" doesn't work: it underestimates speed and distance. The best result is achieved with the 26 inches setting, with a deviation of 2% for both speed and distance.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by squee22 » Aug 29 2017 4:26pm

squee22 wrote:
tomjasz wrote:TSDZ2 Assembly
Great document. Thanks.

this answers some of the questions about how to grease these things. The grease recomended by the manufacturer is FT-EM50L https://www.dowcorning.com/applications ... &type=PROD . There was some questions earlier about me using white lithium grease on my unit pertaining to plastic compatibility and operating temperature. This manufacturer recomended grease does have a slightly higher temp of 150 celsius (white lithium is 120) - additionally this grease is definitely formulated to be plastic compatible, while white lithium is not. If you are unsure what grease to use this is the one. I will regrease at the end of the season and report on what I find. I do not suggest anyone use White lithium until I report back. Use the FT-EM50L. (warning - it's expensive stuff. Like 20 bucks for a little thing on ebay. No wonder the manufacturer used so little grease on my unit.)
Just reposting this to answer the question about grease on the blue gear.

James Broadhurst   10 W

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by James Broadhurst » Aug 30 2017 6:29am

tomjasz wrote:
James Broadhurst wrote: The thing about these types of gears is that they will survive without lubrication. That is after all their main advantage.
Yet all the other motor builders with synthetic gears do spec a lubricant and they do require lubrication. Are we thinking TS doesn't?
Taken in context, my remark alluded to the fact that a metal gear will not survive without lubrication. Those thinking of replacing the gear need to think quite carefully about this. There's not an oil sump on these motors, any of them, so the grease can go anywhere except where its wanted.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by RTIII » Aug 30 2017 10:09am

James Broadhurst wrote:Taken in context, my remark alluded to the fact that a metal gear will not survive without lubrication. Those thinking of replacing the gear need to think quite carefully about this. There's not an oil sump on these motors, any of them, so the grease can go anywhere except where its wanted.
That's quite true.

If I were going to be running a metal gear, without regard to the metal, as a replacement for the nylon one, I'd coat it in the (unfortunately now out of production) Bosch brand "distributor lube" grease because it has such a wonderful ability to not get flung off by rotational forces when hot and therefore thin. ... I'm not at all sure what other brands may have the same properties, but a creative person could come up with a test, such as dabbing a patch of some grease of each of many types on a sample card mounted vertically and insert it into an oven set to, oh, 120F or, what, around 50 C or so, and see which products didn't all end up on the bottom. Bear in mind that whatever the temperature rating for the grease, it has no bearing in this scenario because the test isn't whether the grease survives and still lubricates at any given temperature, but whether or not it stays put.

Do note, however, that these new metal gears are made of copper, I believe, which is fairly soft, and that will help with both lubrication and noise (at the expense of wear).

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by tomjasz » Aug 30 2017 12:57pm

WOW! the only way to buy the molykote is to buy 16kg and repack, or buy Canon printer grease for $11 gram! $55 for 5 grams.

NUTS!

Mobil Aviation synthetic works on my BBSxx.

"16kg pail, and you would be responsible for the yield that comes from that repack + the repack fee. I can send you a quote for the 16kg size or if you are interested on the repack material please fill out the attached form."
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

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Re: New "TSDZ2 Metal Gear

Post by Daytriker » Aug 30 2017 1:37pm

RT111- I doubt very much the replacement gears are copper. Copper is an extremely soft & pliable metal. Most likely they are brass.

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Re: New "TSDZ2 Metal Gear

Post by eyebyesickle » Aug 30 2017 1:44pm

Daytriker wrote:RT111- I doubt very much the replacement gears are copper. Copper is an extremely soft & pliable metal. Most likely they are brass.
yeah, maybe they throw just enough zinc in the mix until it stopped buttering up =P

a lower zinc ratio brass, would more lean towards the 'softness' of copper which they may have been going for to reduce the additional noise ~ metal on metal

I think the 'copper' came up more from inaccurate translations... brass is correct

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Daytriker » Aug 30 2017 2:39pm

Any idea on the best way to extricate the Blue Gear from the shaft for replacement? Do I go from the gear end or the bearing end? Not sure if I need a gear puller or knock out the pin in the gear. Thanks if you can help.
Attachments
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RTIII   1 kW

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Re: New "TSDZ2 Metal Gear

Post by RTIII » Aug 30 2017 3:49pm

Daytriker wrote:RT111- I doubt very much the replacement gears are copper. Copper is an extremely soft & pliable metal. Most likely they are brass.
Certainly I did not make such mistake; I was told that they are nearly pure copper.

Given that it's to replace a NYLON gear, it's entirely reasonable that nearly pure copper be chosen as a material. It's soft, but not as soft as nylon, and it won't have substantial lubrication requirements, just as the nylon doesn't either.

And, I doubt very much that the gears are brass - as anyone competent in even high-school chemistry should be able to tell you, brass is generally used as a decorative alloy as it tends to be brittle and has little strength. Instead, what most people take to be brass used in ANY form of industrial setting, sometimes even formally called "brass", is not brass at all but bronze - Sn (tin) is used instead of Zn (zinc).

99.9% pure copper comes in many commercial grades with a wide range of attributes, from a Brinell hardness ranging from 42 to 100, elongation ranging from 45 to 5%, tensile strength ranging from 32 to 46 ksi, and so on. For this use, it's not a bad choice at all.

In contrast, not only is brass brittle, bronze would perhaps be too strong, and not particularly cheap, either, though there's a HUGE range of choices available.

...I spent some 20+ years working along side a materials scientist, and one picks up a lot of such things. However, you also, these days, have Wikipedia to cure your ignorance. Try this page for copper alloys and their various properties - in particular, note how many alloys are called brass which are actually bronze alloys:

https://en.wikipedia.org/wiki/List_of_copper_alloys

Of course, get your most fundamental education here:

https://en.wikipedia.org/wiki/Copper

In the end, you won't know unless you either have the material analyzed or speak to the person who sourced it in the off chance they know what the hell they are talking about - and they may well not!

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by squee22 » Aug 30 2017 4:18pm

RTIII wrote:
James Broadhurst wrote:Taken in context, my remark alluded to the fact that a metal gear will not survive without lubrication. Those thinking of replacing the gear need to think quite carefully about this. There's not an oil sump on these motors, any of them, so the grease can go anywhere except where its wanted.
That's quite true.

If I were going to be running a metal gear, without regard to the metal, as a replacement for the nylon one, I'd coat it in the (unfortunately now out of production) Bosch brand "distributor lube" grease because it has such a wonderful ability to not get flung off by rotational forces when hot and therefore thin. ... I'm not at all sure what other brands may have the same properties, but a creative person could come up with a test, such as dabbing a patch of some grease of each of many types on a sample card mounted vertically and insert it into an oven set to, oh, 120F or, what, around 50 C or so, and see which products didn't all end up on the bottom. Bear in mind that whatever the temperature rating for the grease, it has no bearing in this scenario because the test isn't whether the grease survives and still lubricates at any given temperature, but whether or not it stays put.

Do note, however, that these new metal gears are made of copper, I believe, which is fairly soft, and that will help with both lubrication and noise (at the expense of wear).
Be careful experimenting with greases to make sure they are non conductive and not harmful to plastics - just in case it gets into the electronics, and so it doesn't eat the gaskets.

This is why I use that white lithium grease - it's generally safe (key word - generally. some still have petroleum distillates in there), despite it having less than ideal thermal and wear properties. You do not want a grease that will act like a solvent and eat your plastics.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by squee22 » Aug 30 2017 4:23pm

Daytriker wrote:Any idea on the best way to extricate the Blue Gear from the shaft for replacement? Do I go from the gear end or the bearing end? Not sure if I need a gear puller or knock out the pin in the gear. Thanks if you can help.
just pull them apart. It's press fit. My shaft fits looser on the bearing that attaches to the motor and slips out at that point. yours appears to fit tight on the shaft and loose on the motor. Regardless - it's all press fit. Just yank em apart.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by RTIII » Aug 30 2017 4:47pm

squee22 wrote:
Daytriker wrote:Any idea on the best way to extricate the Blue Gear from the shaft for replacement? Do I go from the gear end or the bearing end? Not sure if I need a gear puller or knock out the pin in the gear. Thanks if you can help.
just pull them apart. It's press fit. My shaft fits looser on the bearing that attaches to the motor and slips out at that point. yours appears to fit tight on the shaft and loose on the motor. Regardless - it's all press fit. Just yank em apart.
Just as a hopefully helpful point about word choice here, engineers and machinists don't use the term "press fit", rather one of the following:

1) clearance fit: the pieces slide right into one another readily, or;

2) net fit: the pieces just barely go together, sometimes a little lubrication is needed to get them to slide together or apart. In theory, the mating surfaces are exactly the same size. Or;

3) interference fit: the one part is bigger than the other so that at "room temperature" (or, in the case of dis-similar materials, potentially any particular specified temperature) they cannot readily be fitted together unless there's some form of mechanical help, such as a beveled edge and then pressed together, or some such.

If someone told me they were "press fit", I'd presume they meant they were interference fit - not at all easy to get together or apart. And, therefore, because of context here, I guess what's meant is "net fit."

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by squee22 » Aug 30 2017 7:22pm

RTIII wrote:
squee22 wrote:
Daytriker wrote:Any idea on the best way to extricate the Blue Gear from the shaft for replacement? Do I go from the gear end or the bearing end? Not sure if I need a gear puller or knock out the pin in the gear. Thanks if you can help.
just pull them apart. It's press fit. My shaft fits looser on the bearing that attaches to the motor and slips out at that point. yours appears to fit tight on the shaft and loose on the motor. Regardless - it's all press fit. Just yank em apart.
Just as a hopefully helpful point about word choice here, engineers and machinists don't use the term "press fit", rather one of the following:

1) clearance fit: the pieces slide right into one another readily, or;

2) net fit: the pieces just barely go together, sometimes a little lubrication is needed to get them to slide together or apart. In theory, the mating surfaces are exactly the same size. Or;

3) interference fit: the one part is bigger than the other so that at "room temperature" (or, in the case of dis-similar materials, potentially any particular specified temperature) they cannot readily be fitted together unless there's some form of mechanical help, such as a beveled edge and then pressed together, or some such.

If someone told me they were "press fit", I'd presume they meant they were interference fit - not at all easy to get together or apart. And, therefore, because of context here, I guess what's meant is "net fit."
Thanks for teaching me the Mech-E language. I'm EE and never learnt this stuff.

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New "TSDZ2 Blue Gear Change

Post by Daytriker » Aug 30 2017 10:05pm

I don't think it is a Press Fit onto the gear shaft. I tried by hand, prying with a screwdriver & gently with a pair of pliers plus there is a pin at either end. One on the gear side & one on the bearing side. 2 weeks & 2 attempts = no response from Tongsheng either. I was really hoping this would be a good alternative to geared hub motors but although my customer is happy with the replacement kit, I don't think I can recommend this set up.
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Beating side.jpg
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Re: New "TSDZ2 Blue Gear Change

Post by Triketech » Aug 30 2017 10:53pm

Daytriker wrote:2 weeks & 2 attempts = no response from Tongsheng either. I was really hoping this would be a good alternative to geared hub motors but although my customer is happy with the replacement kit, I don't think I can recommend this set up.
Tongsheng may not respond for another week, the sent a number of key people (probably all 3...) to the Eurobike show.

I agree though. It really appeared to have significant potential for the trike market. I'll stick with hubmotors.

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Re: New "TSDZ2 Blue Gear Change

Post by squee22 » Aug 31 2017 3:47am

Daytriker wrote:I don't think it is a Press Fit onto the gear shaft. I tried by hand, prying with a screwdriver & gently with a pair of pliers plus there is a pin at either end. One on the gear side & one on the bearing side. 2 weeks & 2 attempts = no response from Tongsheng either. I was really hoping this would be a good alternative to geared hub motors but although my customer is happy with the replacement kit, I don't think I can recommend this set up.
Check out my video at the 10, and 15 minute marks and you can see a bit of my blue gear and shaft. Compare what you see to your own. Sorry I didn't take much for closeups.

Perhaps there are different versions of this same part - mine just slips apart.
https://www.youtube.com/watch?v=eQVnJ5n ... 2376203357

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Waynemarlow » Aug 31 2017 4:57am

Guys, remember the blue gear is toast anyway so just get your hack saw and cut it away so you can get a bearing puller down the backside of the bearing. Chances are that if the bearing is an interference fit ( which I doubt ) the bearing maybe damaged whilst pulling it off so for the cost of a bearing, its often easier to break up the outer bearing, than to damage the shaft whilst trying to extract it off. If you feel the need to be brutal or the bearing feels suspect anyway then simply toast the bearing.

Here's how if all else has failed in getting the bearing off.

On the bearing there will be a number, write it down. If the number is hidden by being on the wrong side then don't worry, the outer shell usually breaks into just 2 pieces.

If you want to break up a bearing then you can do them in about 10 minutes. wrap the bearing in a bit of rag ( to stop any fragments flying at you ) and then clamp the outer shell in a vice as hard as you can, then give the vice a little bit more by putting a piece of pipe on the handle ( don't be silly here and bend the handle ) then simply tap the bearing or vice with a hammer lightly, the outer cage is incredibly brittle and with it being slightly distorted the shock of the hammer blow usually will shatter it into a couple of pieces. You can usually hear them crack. Don't be silly and really give the vice a blow as you can also break the vice this way, softly softly but getting enough pressure on the outer shell to distort it is the key.

Remove the outer broken case, the balls and ball race, leaving only the inner cage. Now get your angle grinder and grind a flat onto the inner cage to about 1/2 way through or a little bit more, taking care not to damage the shaft ( you can leave a couple of mm of full height against the bearing stop. Now close you vice up enough to just cradle the inner cage, put your shaft onto the vice with the inner cage cradled on the vice jaws. Take a big hammer and cold chisel and hit the flat area leaving an indent on the inner cage ( by grinding it you have softened the cage ). The indent has now expanded the metal and the voila the bearing will be now loose on the shaft.

Be careful on ordering the bearing as each manufacturer will have a particular end code for its tolerance fit.

If the bearing is interference fit as a lot of shaft bearings are these days, as it means less machining to put pins and locking nuts onto a shaft, then its easy to put them back on. Put the shaft and everything that needs to be on it prior to fitting the bearing in a freezer for 1/2 a day, heat the bearing ever so slightly with a hair dryer and the bearing should simply go straight over the shaft as a push fit. The worst case is if you don't get the shaft cold enough and the bearing warm enough as they can grab 1/2 way on and then you have to press them on the rest of the way. Once the bearing is located and on 1/2 way they press fit pretty easy.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by RTIII » Aug 31 2017 12:00pm

Waynemarlow wrote:Guys, remember the blue gear is toast anyway so just get your hack saw and cut it away so you can get a bearing puller down the backside of the bearing. Chances are that if the bearing is an interference fit ( which I doubt ) the bearing maybe damaged whilst pulling it off so for the cost of a bearing, its often easier to break up the outer bearing, than to damage the shaft whilst trying to extract it off. If you feel the need to be brutal or the bearing feels suspect anyway then simply toast the bearing.

Here's how if all else has failed in getting the bearing off.

On the bearing there will be a number, write it down. If the number is hidden by being on the wrong side then don't worry, the outer shell usually breaks into just 2 pieces.

If you want to break up a bearing then you can do them in about 10 minutes. wrap the bearing in a bit of rag ( to stop any fragments flying at you ) and then clamp the outer shell in a vice as hard as you can, then give the vice a little bit more by putting a piece of pipe on the handle ( don't be silly here and bend the handle ) then simply tap the bearing or vice with a hammer lightly, the outer cage is incredibly brittle and with it being slightly distorted the shock of the hammer blow usually will shatter it into a couple of pieces. You can usually hear them crack. Don't be silly and really give the vice a blow as you can also break the vice this way, softly softly but getting enough pressure on the outer shell to distort it is the key.

Remove the outer broken case, the balls and ball race, leaving only the inner cage. Now get your angle grinder and grind a flat onto the inner cage to about 1/2 way through or a little bit more, taking care not to damage the shaft ( you can leave a couple of mm of full height against the bearing stop. Now close you vice up enough to just cradle the inner cage, put your shaft onto the vice with the inner cage cradled on the vice jaws. Take a big hammer and cold chisel and hit the flat area leaving an indent on the inner cage ( by grinding it you have softened the cage ). The indent has now expanded the metal and the voila the bearing will be now loose on the shaft.

Be careful on ordering the bearing as each manufacturer will have a particular end code for its tolerance fit.

If the bearing is interference fit as a lot of shaft bearings are these days, as it means less machining to put pins and locking nuts onto a shaft, then its easy to put them back on. Put the shaft and everything that needs to be on it prior to fitting the bearing in a freezer for 1/2 a day, heat the bearing ever so slightly with a hair dryer and the bearing should simply go straight over the shaft as a push fit. The worst case is if you don't get the shaft cold enough and the bearing warm enough as they can grab 1/2 way on and then you have to press them on the rest of the way. Once the bearing is located and on 1/2 way they press fit pretty easy.
For what it's worth, I generally support this as a "poor man's method" (or, maybe better, "minimalist's workshop method"). ... As I said, it's probably a net fit.

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Re: New "TSDZ2 Blue Gear Removal

Post by Daytriker » Aug 31 2017 1:05pm

Thanks for the Minimalist Removal Method. I think that may also be known as the Hillbilly Method. :) Having checked carefully with a magnifying glass I can confirm that the bearing side is not held in by an allen key. What I think they may have done is initially made & assembled these with the parts as a press/interference fit (whatever) presssed together & then started manufacturing them as a complete assembly. My guess is that BMS or Tongsheng screwed up & sent me the wrong replacement part even though I sent along the serial number. I am waiting to hear back from a couple of places to see if there is a way to dis-assemble or drill out the pin to use the new gear or if I have to order a new part.

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Re: New "TSDZ2 Blue Gear Removal

Post by RTIII » Aug 31 2017 1:29pm

Daytriker wrote:Thanks for the Minimalist Removal Method. I think that may also be known as the Hillbilly Method. :) Having checked carefully with a magnifying glass I can confirm that the bearing side is not held in by an allen key. What I think they may have done is initially made & assembled these with the parts as a press/interference fit (whatever) presssed together & then started manufacturing them as a complete assembly. My guess is that BMS or Tongsheng screwed up & sent me the wrong replacement part even though I sent along the serial number. I am waiting to hear back from a couple of places to see if there is a way to dis-assemble or drill out the pin to use the new gear or if I have to order a new part.
Somewhere on this thread, oh, on or about August 3rd, someone published a copy of an official disassembly / reassembly manual, based on when I saved it into my own disk space. Here it is again, for you...
Attachments
TSDZ2_Assembly.pdf
The Tongsheng TSDZ2 motor disassembly and reassembly manual.
(5.58 MiB) Downloaded 326 times

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Daytriker » Aug 31 2017 2:27pm

Thanks RT111 - The manual is much appreciated.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Waynemarlow » Sep 01 2017 3:28pm

Guys you're making hard work of this, the number of the bearing on the rubber dirt guard is a clue.

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Re: New "TSDZ2 Gear Replacement

Post by Daytriker » Sep 01 2017 4:30pm

Well this has been an interesting project. I had asked the Dealer if they had any information about removing the Blue Gear & the response was not very clear. I contacted PSW since learning that they might be able to help but they pretty much blew me off because I hadn't bought the unit from them. RTIII was kind enough to send me the assembly manual & that was the clue I needed. It seems some of these units have looser tolerances than others & mine happened to be one of the very tight ones. There aren't any key ways or set screws holding this together. However, the procedure for pulling it apart is a little strange & counter intuitive. The process is like this - Firmly clamp the Blue Gear with the Spur Gear facing up into a bench vice. The gear is toast so don't do this if you expect to save the gear. With a couple of screwdrivers pry the upper bearing away from the Blue Gear. This will cause the lower bearing to drop off the assembly shaft. There is also a small brass washer between the lower bearings - watch for it. To re-assemble, grease the hell out of everything & just make sure the Blue Gear is face down so the teeth will mesh properly. Then tap the pieces back together.
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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by Waynemarlow » Sep 02 2017 4:14am

Guys, extracting bearings is all about having even tension on either side of the bearing, making any force, directly upwards. One screwdriver on one side will often not move a net fit bearing, however one on either side often makes it feel easy.

Never and I mean never tap a bearing onto a shaft by hitting the outer cage or even for that matter press a bearing on by pushing on the outer cage. If you think it through each time you load the cage, each ball inside the bearing will indent a very slight mark on the side of the races. The bearings were never designed for this and often I see people complain of a short life on a bearing which can be directly attributed to the way it was installed and not the fault of the bearing.

Do get into the habit of using bits of tube and old deep sockets to press directly on the inner cage to then press the bearing onto the shaft. You can be pleasantly surprised how wide the jaws of your vice will open and how good a " press " it is by simply using good organisation of sockets on either side and then get your beloved to close the vice as you will almost certainly need 3 hands.

The other school boy error is to put one end of the shaft face down with a bearing on it and then press or tap correctly via the inner cage, a bearing onto the other end of the shaft. Most outer bearings are designed to sit proud of the shaft by a few thousandth of a mm, so all the loading is now on the outer shell of the already installed bearing, each time you tap or press from the other end, you are indenting the cage area and will then suffer a shortened life and rough feeling bearing on the bearing you weren't actually changing or installing.

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Re: New "TSDZ2 Torque Sensor Central Motor"

Post by RTIII » Sep 02 2017 10:03am

Waynemarlow wrote:Guys, extracting bearings is all about having even tension on either side of the bearing, making any force, directly upwards. One screwdriver on one side will often not move a net fit bearing, however one on either side often makes it feel easy.

Never and I mean never tap a bearing onto a shaft by hitting the outer cage or even for that matter press a bearing on by pushing on the outer cage. If you think it through each time you load the cage, each ball inside the bearing will indent a very slight mark on the side of the races. The bearings were never designed for this and often I see people complain of a short life on a bearing which can be directly attributed to the way it was installed and not the fault of the bearing.

Do get into the habit of using bits of tube and old deep sockets to press directly on the inner cage to then press the bearing onto the shaft. You can be pleasantly surprised how wide the jaws of your vice will open and how good a " press " it is by simply using good organisation of sockets on either side and then get your beloved to close the vice as you will almost certainly need 3 hands.

The other school boy error is to put one end of the shaft face down with a bearing on it and then press or tap correctly via the inner cage, a bearing onto the other end of the shaft. Most outer bearings are designed to sit proud of the shaft by a few thousandth of a mm, so all the loading is now on the outer shell of the already installed bearing, each time you tap or press from the other end, you are indenting the cage area and will then suffer a shortened life and rough feeling bearing on the bearing you weren't actually changing or installing.
I can agree with all of this, except that it's probably not correct that "most outer bearings are designed to sit proud," though there's likely no one in the world who could say one way or another since there's nobody who has the privilege of having a full survey of all the various designs. I can say that in my world, I've never yet encountered a single "outer" bearing whose shaft did not protrude fully through, or at least flush to the end, of that "outer" bearing. -shrug- Makes no difference to the pertinence of the advice here; absolutely, if the bearing IS standing proud of the shaft, DO NOT use it as a "stationary" point from which to push, not even on the race for this might inadvertently shift the position of the bearing on the shaft. When in that circumstance, for me most often with a gear or pulley on a shaft, I'll use a nut whose outside diameter fits within the inside diameter of the item on the end of the shaft - nuts are cheap and usually good steel, so if one gets trashed somehow, it's no big deal.
Last edited by RTIII on Sep 02 2017 10:53am, edited 1 time in total.

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