I have 2 of these from when Bosch first brought these out. Great, handy tools used professionally and at home. The original is a brushless motor. One of them stutters on start, but it still works after a good bang, its great. Life like.
The motor probably feels stiff because they applied grease to a bushing that needs oiling, I find that a lot with motors these days, they fit bronze bushings that for many a decade were known to need machine oil, but they gob on a lump of grease instead and it ends up reluctant to turn, worst offender I had was my desk fan, when new, it wouldn't turn on low speed at all and barely turned at full, found it was greased, cleaned it all out and oiled it, it's been running great for 12 years...
I bought one of these as a bare unit for about 8 quid purely for the disc mounting part as it is a remarkably convenient way of adapting sawblades to a 1/8" shaft used by small brushless motors for RC planes and such. IThe large bearing can be encorparated into a 3d printed housing quite handily. I build mini fighting robots for a hobby so power tool abuse is a way of life. The 550 brushed motor in these grinders is remarkably spicy from a current perspective.
When Lidl were selling off tools a couple of years ago I bought several of their version of this tool. Super useful in the workshop. I use one with a normal cutting disc, one has a fence attached for straight cuts and another I fitted a ROLOC pad and i use it for sanding, deburring etc. Some of my favourite and mot used cordless tools.
I am actually building something right now that requires a 12V DC motor, boost converter and a LiPo cell. The current spike at the start of the motor kept tripping the over current protection of the cell. After some research it was apparent that the protection MOSFET voltage drop determines the current limit. Instead of digging through tiny SMD MOSFETS, I just used an ATTiny85 and a power MOSFET to make it PWM soft start and the tripping never happened again.
I have a similar sized grinder from Lidl. It is worth paying slightly more for one with a safety tested and approved charger and battery, also it ramps the speed up over a second or so to prevent the stalling issue with this one.
Mine is blue, but it works ok. It overheats easily, but 10 second wait works fine. So, the engineer designed it well, but the finance department decided to leave out parts. 😂 Tanks for saving me from having to take mine apart. It works on reasonably heavy stuff if you take your time. The 3” wheels were mostly used in air-driven grinders. I’ve got a selection of types, including Diamond for cutting glass & ceramic tile as well as metal and masonry. I carry it in a small box on many jobs, just in case I need to cut/grind something. It’s great for quick cutting heavy wires or pipes.
I own two of these, and i can say they are pretty neat. If there is a small cutting job or hard to reach places these little things are best. Sometimes even a regular cordless grinder can't reach places that this one can. The only thing I did right after buying it was replace all the standard batteries, because they are all crap and do not hold the declared capacity right out of the box, and also added a soft start pcb, so than motor will not rape protecting circuit every time it starts.
I actually opened some 18650 batteries from a failed battery pack for a cloned Dyson vacuum: A teeny battery and the rest was sand. I thought how nice, built in fire suppression sand....
Balancing should be made mandatory by law. It increases the life span of battery packs tremendously. Especially when cheap batteries with significantly different internal resistance or capacity are used. The same goes for undervoltage protection in all those gizmos that only have soft power off switches.
I have one of those and took it to work to try it out, not bad but as you said the batteries they are sending with it are not strong enough to cut anything substantial but as you guessed you can buy bigger batteries for it and with it it works great and even able to cut metal and wood.
Just so people know: there is a brushless motor version of this I received from Temu here in the US, it was about $20 shipped and is of a much higher quality. It came with 2 metal wood blades, 6 cutoff discs, and 2 grinding discs. I use it daily, it still runs quiet, flawless and smooth.
Thanks for the analysis, always interesting to see what the cheaper tools offer and what the trade-off is, and if it can be worked around!! I guess the tool is what in the power tool market is sometimes called 10.8V (though Milwaukee irritatingly calls it M12...), since the three battery cells seemed to be marked 3.7 V [ 7:00 ]. Which probably would make the charging voltage 4.2 per cell, or 12.6V over the whole pack.
I like it. I wish I had it 4-5 months ago when I had to cut off many many 8mm rod pieces for a robotics project. Ended up buying a corded grinder for $40 which was an over-kill for my needs.
Very much a 'cost reduced' version of Aldi's Ferrex F-CAG12S. I have one in pieces at the moment to modify it for a specific job. I paid about the same, but with only 1 battery and no charger. No battery gauge on the Ferrex, but it does have variable speed. Overall I was quite impressed with it's mechanical build quality.
I'm wondering where one could buy such small grinding discs - assuming they wear out before the tool gives up the ghost! It looks like the disc guard (which you cerefully marked before removing!) can be rotated to suit the angle the tool is being used at - there's a row of dimples around the central hole...
i wish them luck 😅 mines got 50,000 volts going through the handlebars. xenon strobe light circuit. its also remote with a 200ft range so you can get that perfect timing on the thieving ........ 😂
I have one of these but it lacks voltage indicator and it says brushless motor on the box. :) I love it, it's great for small tasks, but over time it developed a rear motor bearing play. Battery capacity is not far from advertised (1160 mAh if I remember correctly) but they are discharged in maybe 5 minutes and take forever to charge. So I bought 3 of them. :)
This the right size for a tool bag. When you high up, difficult space. Where something needs a quick trim, to be able to fix the problem. Like a tiny cat walk.
I have the OG bosch and its pretty handy. There is some blades available for plastic cutting that might be worth looking into if you are going to use it for cutting electronics apart :D
they got me with that on ali. some device they didnt put a power button on. they asked me to send a picture of the missing power button. because thats insane i lost my money.
Video.. I just had a problem with a set of headphones which died 17 months into an 18 month warranty. Sent a video showing it being charged, and then pressing the power button. They returned 1/2 price. Seems fair enough
Ya gotta get one of them Magnetic Dishes, or just a magnet. It's overall convenient. And may save you from finding some tiny bit someday, that ended up in the motors magnets too. .... not that that's ever happened, to me 🙄
Nice video, Clive. It got me thinking. Would an inductor or even a suitably sized inrush limiter work to stop startup spikes and the tool not working intermittently? I don't know if an inrush limiter would work in this application as they dissipate heat, although I like the idea of giving the tool a 'soft start'.
Clive do you have the cutting wheel mounted the correct way ?? I was always preached to that the metal ring on one side of the cut off disc had to go outside towards the locking nut ?? so the flat surface of the disc was in contact with the "inside" to lay flat to the spindle collar.. Just asking for a friend 🙂
These grinders (i have a Parkside one) are the best for grinding small parts (i've successfully tried converting some standard hex to non-standard-tamper-proof screwdriver bits) and removing excess PCB material from the edges. I've once tried to run it with a different battery form another Chinese tool while original one was charging. Apparently the other battery was not designed for such current as its protection FETs turned into significant amount of smoke after some 2 minutes :)
The same happend to my 18650 retrofit B&D Versapak batteries and their rotary tool, because i underestimated the ramp up current and the BMS locked up. XD
Looks just like the one they were selling in Aldi a few months ago, yes it can struggle on some jobs, handy for the bench to save getting out the main angle grinder. That cut out on first press - I assumed was a safety feature, so it didn't spin up if accidently pressed or knocked in the tool bag, interesting.
I couldn't find a datasheet for the MOSFET in that package but in the sop8 package it is supposed to handle 80A at 25C or 240A pulsed which should be more than enough to start the tool. I wonder if the cells are so out of balance that even when "fully" charged they are well below optimal.
I didn't actually test the cells for balance, but they would be close, as the end of charge voltage was above 12V and the first to reach 4.2V ends the charge.
Thanks Big Clive! Cute little tool with weird battery packs. I wonder if the company sourced crappy batteries and is trying to off load to break even or at a slight loss. Oh well. Great stuff.
I have the blue one from temu ,built a couple more batteries .works ok as a cheap mini grinder but as you say its limited but easier to use than my 4.5" 1010 watt in small places
Would it help to put a chonky capacitor across the battery terminals before the switch? Then that would charge when you popped in a battery and would assist with the startup load. I'm not sure there's enough room for one of sufficient size though.
Even the cheap corded harbor freight grinders cost more than this thing. Impressive you got any cordless tool for that much, with batteries AND cutoff wheels? Maybe not as powerful but that’s a lot of bang for your buck
Wow. Only China would look at what is arguably the most dangerous powertool in anyone's shed & think "This needs to be made more portable & pocket-sized"
This is my favorite new bench damage since the squiggle shaped burn mark
I still prefer the plastic welder squiggle.
that plastic welder squiggle stares me in the face every time i see it!! it's odd watching old videos and NOT seeing it lol
That bench has got LORE
I agree the squiggle gets my vote 👍🏻
The plastic staple is still my favorite.
They even added a ball bearing to the drive shaft instead of only relying on the motor bearings.. you must have picked the premium version ;-)
The premium one has brushless motor in it I think 🙃This one is the business class version 😉
Bar is in hell's basement.
@@WooShell I suspect it was cheaper than getting a motor with a usable bearing. Without it would last maybe 10 minutes.
I have 2 of these from when Bosch first brought these out. Great, handy tools used professionally and at home. The original is a brushless motor. One of them stutters on start, but it still works after a good bang, its great. Life like.
The motor probably feels stiff because they applied grease to a bushing that needs oiling, I find that a lot with motors these days, they fit bronze bushings that for many a decade were known to need machine oil, but they gob on a lump of grease instead and it ends up reluctant to turn, worst offender I had was my desk fan, when new, it wouldn't turn on low speed at all and barely turned at full, found it was greased, cleaned it all out and oiled it, it's been running great for 12 years...
That's called Cha Bu Duo engineering
I bought one of these as a bare unit for about 8 quid purely for the disc mounting part as it is a remarkably convenient way of adapting sawblades to a 1/8" shaft used by small brushless motors for RC planes and such. IThe large bearing can be encorparated into a 3d printed housing quite handily. I build mini fighting robots for a hobby so power tool abuse is a way of life. The 550 brushed motor in these grinders is remarkably spicy from a current perspective.
Bike thieves' new favorite!
Ah, just like the squiggly plastic melt staple, we can now see the grinder cut, and know where we are in the BigClive timeline.
When Lidl were selling off tools a couple of years ago I bought several of their version of this tool. Super useful in the workshop. I use one with a normal cutting disc, one has a fence attached for straight cuts and another I fitted a ROLOC pad and i use it for sanding, deburring etc. Some of my favourite and mot used cordless tools.
I am actually building something right now that requires a 12V DC motor, boost converter and a LiPo cell. The current spike at the start of the motor kept tripping the over current protection of the cell. After some research it was apparent that the protection MOSFET voltage drop determines the current limit. Instead of digging through tiny SMD MOSFETS, I just used an ATTiny85 and a power MOSFET to make it PWM soft start and the tripping never happened again.
I have a similar sized grinder from Lidl. It is worth paying slightly more for one with a safety tested and approved charger and battery, also it ramps the speed up over a second or so to prevent the stalling issue with this one.
The Bosch original version of that tool actually works really well and i use it much more than i expected
The Bosch original is such an amazing problem solver.
They also copied the battery layout as it seems.
Mine is blue, but it works ok. It overheats easily, but 10 second wait works fine.
So, the engineer designed it well, but the finance department decided to leave out parts. 😂
Tanks for saving me from having to take mine apart.
It works on reasonably heavy stuff if you take your time.
The 3” wheels were mostly used in air-driven grinders. I’ve got a selection of types, including Diamond for cutting glass & ceramic tile as well as metal and masonry. I carry it in a small box on many jobs, just in case I need to cut/grind something. It’s great for quick cutting heavy wires or pipes.
Thanks for this teardown , adding a capacitor before the switch may reduce the Inrush current viewed by the battery.
Now I know what a 3 inch tool sounds like.
Some girls like it that wide 😉
@@jasonstclair1329 wide? 😰
@@kisielthe1st wide.
It's a good day when we get a new mark on the bench!
This case seems as precise as something someone did on the first day after getting their 3d printer.
16 GBP death wheel?!? Sign me up.
I own two of these, and i can say they are pretty neat. If there is a small cutting job or hard to reach places these little things are best. Sometimes even a regular cordless grinder can't reach places that this one can. The only thing I did right after buying it was replace all the standard batteries, because they are all crap and do not hold the declared capacity right out of the box, and also added a soft start pcb, so than motor will not rape protecting circuit every time it starts.
Thanks for the upload, its 3 am and you just reminded me to unplug my dewalt I left charging!
Aw, isn't it just the cutest little thing.
I actually opened some 18650 batteries from a failed battery pack for a cloned Dyson vacuum: A teeny battery and the rest was sand. I thought how nice, built in fire suppression sand....
Nice look inside Big Clive. A lot of times the brushes on the commutator has some tightness until seated well.
Hey, I have one just like that!
Finally I managed to get my hands on a weird tool before Clive, appreciate the teardown as always
Balancing should be made mandatory by law. It increases the life span of battery packs tremendously. Especially when cheap batteries with significantly different internal resistance or capacity are used. The same goes for undervoltage protection in all those gizmos that only have soft power off switches.
It's a nice looking little grinder. I could have made use of something like this last year when I was changing the sway bar links on my Honda.
I have one of those and took it to work to try it out, not bad but as you said the batteries they are sending with it are not strong enough to cut anything substantial but as you guessed you can buy bigger batteries for it and with it it works great and even able to cut metal and wood.
Just so people know: there is a brushless motor version of this I received from Temu here in the US, it was about $20 shipped and is of a much higher quality. It came with 2 metal wood blades, 6 cutoff discs, and 2 grinding discs. I use it daily, it still runs quiet, flawless and smooth.
Wow great purchase
They offer it in a choice of colours and don't sell it in pink? Disgraceful!
Thanks for the analysis, always interesting to see what the cheaper tools offer and what the trade-off is, and if it can be worked around!!
I guess the tool is what in the power tool market is sometimes called 10.8V (though Milwaukee irritatingly calls it M12...), since the three battery cells seemed to be marked 3.7 V [ 7:00 ]. Which probably would make the charging voltage 4.2 per cell, or 12.6V over the whole pack.
I have got one of those with a brushless motor. I like it as it is handy for small things to work on.
I like it. I wish I had it 4-5 months ago when I had to cut off many many 8mm rod pieces for a robotics project.
Ended up buying a corded grinder for $40 which was an over-kill for my needs.
Finally the right tool this Christmas for your one relative that has 30 year old gout and bunions.
Getting fancy with the schematics these days, Clive! Nice!
Very much a 'cost reduced' version of Aldi's Ferrex F-CAG12S. I have one in pieces at the moment to modify it for a specific job. I paid about the same, but with only 1 battery and no charger. No battery gauge on the Ferrex, but it does have variable speed. Overall I was quite impressed with it's mechanical build quality.
Any good for stealing bicycles?
😂 what ?
Probably, but I won't test that.
@@dennismugweru2325 It is cheap, light weight and small. Easy to carry and conceal. If they can cut padlocks I can see a big market for them.
Thanks Clive.
Very interesting.
Ahh, love these BOLTRs from Clive. Something's missing though... Oh yes, "Focus you f***!"
Yes i hear AVE in the background
I lock focus to avoid those issues.
Three inch...seems to be the standard size...I'm used to the bigger ones
I'm wondering where one could buy such small grinding discs - assuming they wear out before the tool gives up the ghost!
It looks like the disc guard (which you cerefully marked before removing!) can be rotated to suit the angle the tool is being used at - there's a row of dimples around the central hole...
3 inches is the standard size? I thought it was 6 inches! 😂😂
@FamilyOfEyles Screwfix in the UK.
that size is common on small air powered grinders, both straight and angle. They are handy for tight spaces but the small discs wear quite fast.
Size queen 🤦♀️
"Universal bicycle lock key"
i wish them luck 😅 mines got 50,000 volts going through the handlebars. xenon strobe light circuit. its also remote with a 200ft range so you can get that perfect timing on the thieving ........ 😂
I have the DeWALT DCS438, 3” cut-off tool and it’s amazing. Can’t imagine how this thing might compare. Getting ready to be entertained!
Two constants of British TH-cam:
Ashens’s brown sofa
Bigclovedotcom’s bench
Clove?
we should have put gear oil on the RS 550 bushing to prolong the life of the RS 550 motor; the back part is the bushing that is easily damaged.
1:20 The bench gets a new scar for posterity.
Might be stiff because it's got big melonfarmer magnets in there.
Looks identical to a Parkside brand mini grinder I had, same triangle battery etc. That had opposite problem of not turning off!
my dremel has started doing that
I have one of these but it lacks voltage indicator and it says brushless motor on the box. :) I love it, it's great for small tasks, but over time it developed a rear motor bearing play. Battery capacity is not far from advertised (1160 mAh if I remember correctly) but they are discharged in maybe 5 minutes and take forever to charge. So I bought 3 of them. :)
This the right size for a tool bag. When you high up, difficult space. Where something needs a quick trim, to be able to fix the problem. Like a tiny cat walk.
I have the OG bosch and its pretty handy. There is some blades available for plastic cutting that might be worth looking into if you are going to use it for cutting electronics apart :D
"and asking me to send a photo of the grinder not working." lol that would be a very interesting picture
they got me with that on ali. some device they didnt put a power button on. they asked me to send a picture of the missing power button. because thats insane i lost my money.
Video.. I just had a problem with a set of headphones which died 17 months into an 18 month warranty. Sent a video showing it being charged, and then pressing the power button. They returned 1/2 price. Seems fair enough
New bench lore!
That's a cutoff saw, not an angle grinder. I have the Milwaukee version: very handy for cutting metal into shorter lengths for transport.
There are options to get grinding disks with it too.
I have the electric ratchet and for infrequent use it just does the job as described
Ya gotta get one of them Magnetic Dishes, or just a magnet.
It's overall convenient. And may save you from finding some tiny bit someday, that ended up in the motors magnets too.
.... not that that's ever happened, to me 🙄
It appears as if you are slowly creating a giant Feynman diagram on your bench.
2:28 Did you try it out on your left thumb?
Yes.
Would have wanted to see you cut actual stone or metal with it to see performance also.
Nice video, Clive. It got me thinking. Would an inductor or even a suitably sized inrush limiter work to stop startup spikes and the tool not working intermittently? I don't know if an inrush limiter would work in this application as they dissipate heat, although I like the idea of giving the tool a 'soft start'.
The voltage drop in those Chinesium cells is also temperature dependent. Above 20C they work better.
Clive do you have the cutting wheel mounted the correct way ?? I was always preached to that the metal ring on one side of the cut off disc had to go outside towards the locking nut ?? so the flat surface of the disc was in contact with the "inside" to lay flat to the spindle collar.. Just asking for a friend 🙂
Normally I'd put it on label out. Not sure why I put it on that way. It seems to be a divisive subject online.
Made ideally for the bicycle theft market.
Thank you for the explanations, I have a lot of these batteries.
These grinders (i have a Parkside one) are the best for grinding small parts (i've successfully tried converting some standard hex to non-standard-tamper-proof screwdriver bits) and removing excess PCB material from the edges.
I've once tried to run it with a different battery form another Chinese tool while original one was charging. Apparently the other battery was not designed for such current as its protection FETs turned into significant amount of smoke after some 2 minutes :)
Now, Clive has a cheap(er) version of AvE's box opening tool!
Im glad you did a review of these grinders because I was thinking of getting one... It's ust a shame that they do not do them in Barbie Pink 🙂
Yeah. I'd have bought the pink one.
You know you watch far too much youtube when you recognise every battlescar on Clive’s bench …
they are pretty good, I use it as a big dremmel
Big Clive BOLTR for the win.
Wow they repurposed the rotary cat polisher that was on AliExpress
Why would you polish a cat?
That is the T from tharging. 😊
The same happend to my 18650 retrofit B&D Versapak batteries and their rotary tool, because i underestimated the ramp up current and the BMS locked up. XD
Thank you BC. 👌👏👏👏
Thank you, love your work
Looks just like the one they were selling in Aldi a few months ago, yes it can struggle on some jobs, handy for the bench to save getting out the main angle grinder. That cut out on first press - I assumed was a safety feature, so it didn't spin up if accidently pressed or knocked in the tool bag, interesting.
You might like to look into reviewing one, it uses a usb c socket, so there might be more villainy at work.
I couldn't find a datasheet for the MOSFET in that package but in the sop8 package it is supposed to handle 80A at 25C or 240A pulsed which should be more than enough to start the tool.
I wonder if the cells are so out of balance that even when "fully" charged they are well below optimal.
I didn't actually test the cells for balance, but they would be close, as the end of charge voltage was above 12V and the first to reach 4.2V ends the charge.
Oh, this seems like a popular battery module for 3S lithium units.
It's sold as a bare case and PCB kit, so I'g guess there are many small factories in China spot welding random cells into them.
I have some older Ryobi one+ branded batteries that do that. if the inrush surge is too big they lockout.
That would make a cute little motor burn out video. Maybe that's too brutal a thing to do.
Perfect "Clive" mat cutter with amazing direct drive and quality bearing?
He grinds, he flicks things off, and then something feels a bit stiff. Cheers BC 🥃
Thanks!
Thanks Big Clive! Cute little tool with weird battery packs. I wonder if the company sourced crappy batteries and is trying to off load to break even or at a slight loss. Oh well. Great stuff.
That would be useful for cutting metal packing bands, very intermittent use.
Any brand markings on the batteries? Would be curious if the marked capacity is any where near the actual. Maybe you can post short letting use know?
I have the blue one from temu ,built a couple more batteries .works ok as a cheap mini grinder but as you say its limited but easier to use than my 4.5" 1010 watt in small places
Would it help to put a chonky capacitor across the battery terminals before the switch? Then that would charge when you popped in a battery and would assist with the startup load. I'm not sure there's enough room for one of sufficient size though.
It might help with that initial spike.
"Why does it feel stiff?" Maybe because you're playing with it.
An angle grinder for the price of a McDonald's hamburger and fries. Who'd of thought of that? Nice one Big Clive, thanks. Enjoy!
nice, could use something between a dremel and the big beasty. csn aslo recomend pulitio..palutio...drills 😂, dirt cheap but great devices.
I wonder how easy it is to get replacement disks ?
For Office use only!
Not recommended for bank robbers then. 😆
This is NOT your old Aunty's fingernail buffer kids. 8^) Don't think I'll be doing any weld preps on 1/2" wall steel pipe with this one. Cheers!
How long will take to cut the 2.5 kg chain I just bought the lock my new bike??
😢
Could you fix the batteries by soldering in the missing MOSFET or is opening the batteries destructive?
It would be viable if the lithium cells were up to the current demand.
Ah yes, the _bulglars special_
Would be ideal for a bicycle thief. Small and light enough to carry around without being noticed.
Still quite noisy though. Picking the lock would be less suspicious.
Rongda motor? Rongda rongda! Shipped in from Planet Arg?
Even the cheap corded harbor freight grinders cost more than this thing. Impressive you got any cordless tool for that much, with batteries AND cutoff wheels? Maybe not as powerful but that’s a lot of bang for your buck
Wow. Only China would look at what is arguably the most dangerous powertool in anyone's shed & think "This needs to be made more portable & pocket-sized"
Clive I might be totally wrong but I think the tool cuts out every so often to prevent the motor from overheating. And burning its self out. ?
This is from cold. Some have a thermal switch too.
Not Clive Pink ?
If it had been available....
What about adding a starting cap to the grinder, wouldn't that stop the spike, seems thats what they do with all the big ac motors.
It could be used as a reservoir for a pulse of current. In the AC motor application it's usually for the start winding.