How to Battle-Harden Motors

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  • Опубликовано: 17 авг 2024
  • In this video, I show you how to help prevent your motors from failing during combat. Motors take a lot of abuse and the magnets are prone to shattering or coming loose on brushless motors. 'Battle-hardening' your motors can prevent this damage and allow you to dish out more damage to your opponent!
    Follow me on Facebook: / robertcowandiy
    If you'd like to help support my channel, use the following link to shop on Amazon:
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    Glass Microspheres - amzn.to/2krib2f
    Loctite Heavy Duty Epoxy - amzn.to/2KYWvpB
    00:00 Intro
    00:28 What's Needed
    02:40 Before/After
    05:40 Process Synopsis
    06:29 Mixing Epoxy
    09:15 Stator Hardening
    17:15 Rotor Hardening
    25:50 Outro
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Комментарии • 136

  • @forest487
    @forest487 2 года назад +5

    I would recommend wearing a respirator for the particles of glass beads, also doing it in a ventilated area for the apoxy

  • @joer7151
    @joer7151 5 лет назад +15

    You did an awesome job framing it for the camera and letting us see exactly the "tactile feel" of what's right

  • @rogermunch4659
    @rogermunch4659 2 года назад +2

    (I am that machinist etc guy across the street from your dad) We had dryer motor fail. I took it apart and found one of the magnets came loose....poorly glued! Your glue & micro-spheres fix between magnets etc is a great idea for much better holding power.....also keeps moisture from dryer out of those areas. I'll no doubt use the micro-spheres for other applications to add control and lessen the running & dripping problem in tougher situations. If motors were made this way it would sure increase their life times. Thanks for your knowledge sharing!

    • @RobertCowanDIY
      @RobertCowanDIY  2 года назад +2

      Hey Roger! Glad the fix worked. It was the first time I heard about micro-balloons but they really do make the epoxy easier to use. It's also a bit easier to sand and shape after it cures too.

  • @nerddub
    @nerddub 2 года назад +1

    I used to build battle bots out of RC cars with nails melted into the fenders and drill motors and circular saw blades. In the 20 years since then, I've learned a lifetime of electronics and mechanical knowledge. This channel has inspired me to build a new bot, I've learned so much from watching you. The fights on TV were always cool, but this is what I always wanted to see from them. Thank you!

  • @UloPe
    @UloPe 6 лет назад +30

    Actually the blue epoxy in the bell is for rotational balancing which you're undoing by filling the gaps with epoxy. Although I guess for your application perfect balance isn't as important as it would be for the usual aerial use.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +32

      AH, ok. Yeah, throwing off the balance isn't a big deal, not when you're adding 8 pounds of spinning mass...

  • @seetheflow
    @seetheflow 6 лет назад +5

    Robert, I really appreciate the videos you put out there. Its very handy both seeing guides likes this, as well as build reports and post battle breakdowns of the bot. You are doing a great thing for the community :)

  • @andrew_boe
    @andrew_boe 6 лет назад +8

    This is awesome. Big help for a new builder. In process on my first antweight.

  • @Sillyzombie666
    @Sillyzombie666 6 лет назад +25

    i never knew people did this

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +7

      not everyone does and it's not absolutely necessary, but it really does help prevent motor issues.

    • @RennieAsh
      @RennieAsh 5 лет назад +4

      I opened a sander once and they use epoxied motors to try and stop things breaking from the vibration.

    • @TheBlackEventorizon
      @TheBlackEventorizon 3 года назад +1

      Back in the 'old days' with brushed motors the UK HW builders would machine plastic or aluminium inserts for their motors to keep the magnets in place. I guess they could have used expoxy but it would have taken so much that it was probably cheaper to custom machine blocks and if the motor did break they could move them to the new motor.

  • @isettech
    @isettech 5 лет назад +2

    looks like you could use a 5cc syringe and applicator needle and just squirt it into the gaps as needed. They make blunt end needles specifically for applying glues and lubricants.

    • @RobertCowanDIY
      @RobertCowanDIY  5 лет назад

      This could certainly work, but it's thick enough for it to not be an issue. I just didn't have any syringes on my at the time.

  • @herobrineharry7698
    @herobrineharry7698 2 месяца назад

    I know this is an old video- have you ever tried using thermal adhesive instead of standard epoxy? Might avoid heating issues.

  • @zhuofanzhang9974
    @zhuofanzhang9974 2 года назад

    Accidental ASMR, I would be coming back for this video for many times in the foreseeable future...

  • @JonathanRansom
    @JonathanRansom 6 лет назад +3

    Thanks for sharing your tips!

  • @waynefilkins8394
    @waynefilkins8394 3 года назад +1

    This is fucking cool. I used to watch battle bots back in the day and they were always getting rammed and having motors stop working pretty easily...I never understood it. It's crazy to see how far this stuff has come along over the years, that people are doing stuff like this to the motors. I guess if I ever make one of these things now I know :)

    • @RobertCowanDIY
      @RobertCowanDIY  3 года назад

      There's a lot of little tips and tricks to keep stuff running when it's being beat to hell.

  • @brian2k1
    @brian2k1 6 лет назад +1

    seems like a great 3D printer project to make a "wiper" jig, especially for the inside scraping. fits around the shaft with a silicon wiper blade. I have an idea in mind but no motors to test out the idea.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +3

      I had that exact same idea, but decided to just test it out with a small motor. It went so well I never ended up making the wiper. But I'm sure that would work great.

  • @robertwood6297
    @robertwood6297 4 года назад +1

    explained really well

  • @hacklabdesign
    @hacklabdesign 6 лет назад +3

    this is very helpful,thnx Rob

  • @aaronrosner8446
    @aaronrosner8446 5 лет назад +1

    Just buy a big box of those crappy plastic syringes and use those. Mix the eppoxy externally when when it's the way you like it put it in. You can even buy ones with extended nozzles that end at an angle for getting all the way down inside the outrunner.

  • @chrismiksovsky5871
    @chrismiksovsky5871 6 лет назад +3

    Good to have seen this done and will try myself. I know you mentioned other epoxies, and I can’t help but wonder if a “metal” epoxy like JB Weld might afford even more holding strength. Anyway, just bought some glass microspheres through your link. Thanks for another cool video.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +3

      I've used both the normal 5 minute epoxy and the 'metal' one. I haven't seen one fail yet, so I can't comment on any difference.

    • @revimfadli4666
      @revimfadli4666 6 лет назад +1

      does the metal epoxy conduct heat better?

    • @Mr-E.
      @Mr-E. 4 года назад +1

      @@revimfadli4666 Good question Revi, I wonder this as well

  • @jimbotron8552
    @jimbotron8552 Год назад

    just use a thicker epoxy. I use kwikweld and it's pretty thick

  • @PedrinbeepOriginal
    @PedrinbeepOriginal 6 лет назад

    Wow... Really nice idea! Thanks Robert

  • @huckstirred7112
    @huckstirred7112 2 года назад

    epoxy will not stick to shoe polish .put some in the bearing . you can by a stuff that serves the same purpose from Brownells gunsmithing supplies

  • @chanakyasinha8046
    @chanakyasinha8046 5 лет назад

    The heating issue is due to vibration caused in the molecules of glass fibre when magnetic field flux cuts through it. I m saying if you add such substance which have very poor permeability(i think those stiff molecular settings) will not have heating issue if used in glass fibre. Example, if u add iron fillings the glass fibre portion will heat up toouch, so i guess using those substance which have lower action reaction for magnetic field. Sandpaper is good idea to give even finish. I seen this first time, thanks for posting such videos. It helps

  • @renats8465
    @renats8465 4 года назад +1

    How to remove stuck pulley on the motor shaft?

  • @b5a5m5
    @b5a5m5 Год назад

    00:00 Intro
    00:28 What's Needed
    02:40 Before/After
    05:40 Process Synopsis
    06:29 Mixing Epoxy
    09:15 Stator Hardening
    17:15 Rotor Hardening
    25:50 Outro

    • @RobertCowanDIY
      @RobertCowanDIY  Год назад

      Awesome, thanks! Added! I have way too many old videos before the chapter feature existed.

  • @Sursion
    @Sursion 5 лет назад

    My antweight doesn't have enough room in it for a pulley system so I have to use direct drive. This will help a lot in preventing damage, the shaft has already bent just from hitting some coke cans >.>

  • @thomaslum2
    @thomaslum2 5 лет назад

    Thanks for this, really informative!

  • @The2shao
    @The2shao 4 года назад +1

    Since I’m using this for a Electric skateboard application which has motor sensors and all that good stuff , will this affect the sensors And or the rotation of the motor ?

    • @adriankern1006
      @adriankern1006 4 года назад

      That's a good question! My motor is sensored also! Did you know it now? Did you test it? I'm also scare about the heat

  • @poppypopsocks3033
    @poppypopsocks3033 6 лет назад

    love you videos so well done and i do like your machining videos as im a cnc setter/programmer and enjoy seeing what you make lol keep them vids coming.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +1

      thanks, I plan on making many more videos like this.

  • @magicmanspaz
    @magicmanspaz 5 лет назад +2

    Just did my first set of drive motors. Same as yours 4238. I found i was able to clean up the shell later with a little cordless die grinder on slow speed with a little wire brush. Came up perfect and the brush unlike sandpaper does not start to wear parts of the shell. Also i opted only to glue the shell/magnets in and not coat the windings as my theory is if you fill the grooves in the windings the motor cant draw air through to cool. What are your thoughts? Why did you opt to glue the windings as they dont move and seem solid enough no to come apart during shock?

    • @jpjay1584
      @jpjay1584 4 года назад

      absolutely agree

  • @raghavthakar2320
    @raghavthakar2320 6 лет назад

    Hi! Lived the video! I had a question regarding combat robot categories. So in the US, ant-weight is 450 grams (1 lb) right? What's the size limit in this category for rollers? Thanks!

  • @esk8jaimes
    @esk8jaimes 3 года назад

    How would this apply to electric skateboard hub motors?

  • @magicmanspaz
    @magicmanspaz 5 лет назад

    what is your opinion on battle hardening these cheap escs? I know some people have expoxy covered the boards parts excluding the fetts. i wonder if there would be any issue with using electronic potting epoxy to dip the esc and let the extra run off then when hard heat shrink and have the whole thing a solid mass?

  • @thebestpaintballer
    @thebestpaintballer 6 лет назад +1

    love ur videos man! I would love it if you could mill some things for me. Do you have a website with prices?

  • @LydellAaron
    @LydellAaron 3 года назад

    Curious, what is the temperature rating of the epoxy you are using?

  • @ResettisReplicas
    @ResettisReplicas 6 лет назад

    Do you have any tips for brushed motors - apart from Kitbots' guide? I know I'm an old grandpa for continuing to use those but I'm learning

  • @amirbk60
    @amirbk60 4 года назад

    Robert, does this reduce the audible noise (whistle noise) at high rpms? If not would you explain what was the purpose behind what you showed in this video. Thank you!

  • @AngleGroupProductions
    @AngleGroupProductions 4 года назад

    Would you recommend doing this on a sealed motor?

  • @noisyaudio
    @noisyaudio 6 лет назад +1

    But won't the rotor will be unbalanced after this? Could you test for vibration before and after the epoxy infill mod.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад

      If you do it poorly, it might be slightly off-balance. But for combat, it will be driving ~8 pounds of spinning metal that's not nearly as balanced, so it shouldn't make any difference. I can practically balance a nickel on my chassis when the weapon is running, there's very little vibration.

    • @noisyaudio
      @noisyaudio 6 лет назад +1

      Yeah, I guess you're right. After a few nicks out of the weapon it becomes a moot point. Excellent vids BTW.

    • @RennieAsh
      @RennieAsh 5 лет назад

      You could always try your own balancing by holding the motor in your hand, adding temporary mass to a side until it feels smoother, then add a more permanent mass. That’s if your motor seems extremely unbalanced, but most likely won’t matter due to the large mass of weapons

  • @starfilmsanimation
    @starfilmsanimation 6 лет назад

    Would this work with some other filler? Something like fine wood or polycarbonate sawdust? or maybe plaster?

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +1

      Not sure what problem you're trying to solve. Plaster would be very brittle, and wood fibers wouldn't be very strong, and could potentially be heavier.

  • @riteshsingh420
    @riteshsingh420 5 лет назад

    Can same this can be done with the DC motors???for middle weight category???

    • @RobertCowanDIY
      @RobertCowanDIY  5 лет назад

      Sure, the process is pretty similar, you're just using epoxy to make sure the magnets stay where you want them to stay.

  • @imashovel2747
    @imashovel2747 5 лет назад

    Does this work for all weight classes or different weight classes have different methods

    • @RobertCowanDIY
      @RobertCowanDIY  5 лет назад

      The process is pretty much the same for all weight classes. We did the same thing on our heavyweight motors.

  • @MegGriffin45
    @MegGriffin45 2 года назад

    Would you recommend doing this for brushless outrunners in antweights? I just want to make sure that I'm on the right track.

    • @RobertCowanDIY
      @RobertCowanDIY  2 года назад +2

      Absolutely. Any brushless motor that's going to see combat can benefit from this. There's almost no downside.

    • @MegGriffin45
      @MegGriffin45 2 года назад

      @@RobertCowanDIY Awesome. Thanks for letting me know.

  • @waynefilkins8394
    @waynefilkins8394 3 года назад

    I saw some new motors with glue or something in them and they looked kind of like these

  • @Blox117
    @Blox117 2 года назад

    so would this make a motor quieter? there is always noise when turning a motor even when it's unpowered

    • @RobertCowanDIY
      @RobertCowanDIY  2 года назад +1

      No, if anything, it will be noisier. If your motor is noisy when it's unpowered, you most likely have some crappy bearings or dirt/dust somewhere.

    • @Blox117
      @Blox117 2 года назад

      @@RobertCowanDIY no its a large direct drive motor, these always make noise when turning

  • @samuelschuur7044
    @samuelschuur7044 6 лет назад

    Did you end up liking using the propdrive motors? Would you recommend them to someone else or would u pick a different motor.

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +1

      I loved them, very good motors. I went an entire competition on the same motors. They're still fine and I will use them at the next event. After going through 2 competitions, I only broke one motor, which is good considering the hits I took!

    • @stiubelucian6367
      @stiubelucian6367 2 года назад

      @@RobertCowanDIY can you tell me the torque for this motor or how to calculate it?
      I am looking for a brushless for sumo mega combat, but i don't find the torque constant anywhere.

  • @53rdcards
    @53rdcards 6 лет назад

    Would 15 minute epoxy make your life easier? Or would it be to runny?

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад

      You can certainly try it, I'm just telling you what worked best for me.

  • @n.talbert
    @n.talbert 2 года назад

    does this only work on outrunner motors?

    • @RobertCowanDIY
      @RobertCowanDIY  2 года назад +1

      It's less of a concern for inrunners since the magnets aren't on the outside and susceptible to damage.

    • @n.talbert
      @n.talbert 2 года назад +1

      @@RobertCowanDIY thank you. Just ordered parts to make my first bot. Trying to learn as much as fast as possible. Your videos are amazing.

  • @ethanli2045
    @ethanli2045 5 лет назад

    Would it be practical to battle harden a fairyweight motor?

    • @bldjln3158
      @bldjln3158 5 лет назад

      If you have the weight to spare, yes.

  • @spunkywizard5742
    @spunkywizard5742 6 лет назад

    Would you still be able to do this with inrunner motors or is this technique specifically for outrunner motors?

    • @RennieAsh
      @RennieAsh 5 лет назад

      SpunkyWizard I guess it works on those too assuming you can open them and apply the epoxy neatly. Commercial products use epoxied brushed motors

  • @adriankern1006
    @adriankern1006 4 года назад

    I thinking about to do that with my very huge alien aps 7000w motors, I'm just scared about the heat! Doesn't the engine overheat more easily if I seal it like this?

    • @RobertCowanDIY
      @RobertCowanDIY  4 года назад +4

      Technically, yes it does insulate the motor and it will get hotter. However, a motor with shattered magnets doesn't really do anything. Trust me on this one, do this or you'll have shattered magnets. Let's say the epoxy DOES cause the motor to heat up more. If that extra insulation makes the motor overheat in 3 minutes, you have other problems like mechanical friction or you're pushing the motor too hard.

    • @adriankern1006
      @adriankern1006 4 года назад +1

      @@RobertCowanDIY thanks for your fast awnser! the braking with the motor heat them up! That's why I'm think that can be a problem on my moutain e-skate!

    • @RobertCowanDIY
      @RobertCowanDIY  4 года назад +2

      @@adriankern1006 Those are very different applications. You don't typically use braking on a weapon motor, it will generate a lot of heat! It's also not important to spin down the weapon quickly, only spinning it UP quickly.

  • @Bluewhalebig
    @Bluewhalebig 6 лет назад

    Could this be done by applying the epoxy, then putting the two pieces of the motor together, then running the motor until well after the epoxy sets? Maybe even slowly increasing the speed of the motor as the epoxy sets, and/or very gently shaking it periodically throughout the process? Would doing this "role" the epoxy when it reaches a certain point in the curing process, like how erasers do this when you erase something? Would the heat generated by the motor moving affect the curing process? Epoxy shrinks as it cures, so it seems like if none of these aforementioned issues occur, this should not create additional friction when is use. If it works, you would have a perfect fit, of sorts. You could also apply some kind of friction reducing coating or lubrication afterwards to reduce the friction when the motor gets impacted. Has anyone tried this?

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад

      I guess you could do this, but I'm not sure the problem you're trying to solve. It's pretty easy to get everything balanced and evenly distributed. As I said in another comment, this is only adding about 1% to the weight, so it's not that crucial to get it perfectly even.

    • @Bluewhalebig
      @Bluewhalebig 6 лет назад

      Mostly because I thought it might be a bit more efficient. I was thinking that this might distribute the epoxy more evenly and also save time. Using the motor to distribute the epoxy would do both sides at the same time and require less hands on work, allowing you to work on something else while the rotation of the motor does the work for you. So, even if the precision of the epoxy distribution isn't so important, I thought it would still be worth doing purely because it would be easier and less time consuming to do.
      Anyways, thanks for the video, I never would have thought to do this at all. Your channel will come in very handy!

    • @dilbert0815
      @dilbert0815 6 лет назад +1

      It Would only distribute the epoxy in the bell, not in the stator.
      However there is a airgap in the motor design between stator an rotor.
      Your idea would end up with a rather small remaining gap as the epoxy would still be thick on the magnets and stator poles.
      This may likely jam already on small temperature changes caused by parts shrink/expand over temperature.
      Lastly the smaller gap will also being more critical to allow smaller partikels during combat to get in the gap and jam the motor.

  • @jeevanshrestha8888
    @jeevanshrestha8888 5 лет назад

    can I use sand instead of the micro sphere................

  • @RX7GSLSEowner
    @RX7GSLSEowner 4 года назад

    Robert, did y'all do this to Copperhead?

    • @RobertCowanDIY
      @RobertCowanDIY  4 года назад

      Of course. All the motors were epoxied. I'm pretty sure every team does this with their motors, or else the magnets just explode into dust.

  • @mrsqueakyvoice97
    @mrsqueakyvoice97 6 лет назад

    Would epoxy putty work for this?

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад

      I'm sure it would work, but it would be very tricky to get it into all the places you need it to go. You need something with a bit more viscosity to it. You could certainly try the putty, but I'm not sure what problem you're trying to solve by using that instead. It's just going to be harder to use.

  • @bobadingo
    @bobadingo 9 месяцев назад

    Don't use OutRunner motors for robot wars! use in runners.. .

  • @pruthavparab1077
    @pruthavparab1077 5 лет назад

    my motor is not separating

  • @tmlrobotics5446
    @tmlrobotics5446 6 лет назад +1

    Could you use flour?

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +1

      um, do you mean flour? I'm not really sure. I'd probably just do plain epoxy before I tried that.

    • @tmlrobotics5446
      @tmlrobotics5446 6 лет назад

      haha yeah, okay. Probably a horrible autocorrect gone wrong.

  • @Jawa42rider
    @Jawa42rider 5 лет назад

    How many kv scorpion motor is sufficient for 16 kg weapon moving

    • @RobertCowanDIY
      @RobertCowanDIY  5 лет назад +2

      There are far too many variables missing from this question. What's the voltage, what's the MOI of the weapon, what's your target tip speed, what's the diameter?

    • @Jawa42rider
      @Jawa42rider 5 лет назад

      33.3 voltage

    • @Jawa42rider
      @Jawa42rider 5 лет назад

      My target tip speed is approx 10k RPM

    • @Jawa42rider
      @Jawa42rider 5 лет назад

      My weapon is virtical spinner

    • @Jawa42rider
      @Jawa42rider 5 лет назад

      Weapon diameter is 14cm but with its teeth its diameter is 20cm

  • @quasarbound8155
    @quasarbound8155 2 года назад

    OK something is off with utube or my account.....this video says I disliked it and that is not true ....I only liked it ...I love Team Rob (COPPERHEAD)...I REALLY DONT KNOW ....I'm sorry

  • @lalithkishore3774
    @lalithkishore3774 6 лет назад

    Can I do this in racing drone motors

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад

      I don't see why not.

    • @jamble7k
      @jamble7k 6 лет назад

      unbalanced motors are a much bigger deal with quads imo, vibration can cook your escs (gyro noise)

    • @RobertCowanDIY
      @RobertCowanDIY  6 лет назад +1

      I think people are over-thinking the additional weight. The motor weighed 329 grams before adding epoxy and 333 afterwards. So I'm adding 4 grams to a 300+ gram motor, or adding 1.2% extra. I doubt that's enough to make it off-balance, but I could be wrong.

    • @lalithkishore3774
      @lalithkishore3774 6 лет назад

      jamble7k I don't think it matters but a lot because I just got some unbalanced motors from bangood and those are like so much wobbly and I didn't cook any esc ,and my doubt we can just apply it for stator

  • @MiguelEduardoVenegasMonroy
    @MiguelEduardoVenegasMonroy 4 года назад

    Can I do this in rov motors ?

    • @RobertCowanDIY
      @RobertCowanDIY  4 года назад

      are they unique in any way? motors are motors usually. what are you trying to protect them from?

    • @MiguelEduardoVenegasMonroy
      @MiguelEduardoVenegasMonroy 4 года назад

      @@RobertCowanDIY from water, because i see in other tutorial the people use this techniques

    • @RobertCowanDIY
      @RobertCowanDIY  4 года назад +1

      @@MiguelEduardoVenegasMonroy This isn't intended to waterproof a motor, but to keep the magnets from exploding when they get hit.

  • @jimbit22
    @jimbit22 6 лет назад +1

    First mix A+B and then mix the spheres (filler).

    • @daveanderson2316
      @daveanderson2316 6 лет назад

      jimbit22 There's always that one guy.... congratulations. ..

    • @jimbit22
      @jimbit22 6 лет назад +1

      Yeah, there always seems to be.. If you had the same failures with the resin not curing as i have had, you would be commenting the same..

    • @HitLeftistsWithHammers
      @HitLeftistsWithHammers 2 года назад

      @@daveanderson2316 and you were that guy. Congratulations.

  • @waynefilkins8394
    @waynefilkins8394 3 года назад

    I'm here because I have invented something which teenagers will use which has these types of motors. So I need to battle harden them for teenagers to use and not break the product lmao

    • @RobertCowanDIY
      @RobertCowanDIY  3 года назад +1

      This is really more for shock. You would need to do some stuff in the electronics to make sure they don't overheat and such.

  • @cvspvr
    @cvspvr 4 года назад +1

    could i use cocaine instead of glass microspheres?

  • @mateuseduardo9914
    @mateuseduardo9914 6 лет назад

    How to make combat robot

  • @RennieAsh
    @RennieAsh 5 лет назад

    18:16 did I hear Icky Mouse?

  • @Doc_Fartens
    @Doc_Fartens 6 лет назад +1

    You gotta work on not saying "umm" 50 times a sentence.