Stirling Engine Generator Mk4 (Rocket Stove!) Part 9

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  • เผยแพร่เมื่อ 3 ก.พ. 2025

ความคิดเห็น • 106

  • @Sammy-eb2cy
    @Sammy-eb2cy 11 หลายเดือนก่อน +7

    Very happy to see your success! 45w for your first run is a great starting point. I can't wait to see the next modifications. Keep your videos coming.

    • @Sammy-eb2cy
      @Sammy-eb2cy 11 หลายเดือนก่อน

      What is the stroke of your pistons?
      You may be able to use a thin sheet of stainless steel for the seal material if it doesn't stroke to far (.1mm to .25mm thick) If you modify the piston so it doesn't stroke past the face of the cylinder. Connect the SS seal close to the center of the piston. And connect it to the outside of the existing cylinder flange. (You may have to extend the flange diameter) Think of it as a giant "fender washer", for the idea, large OD, small ID. You may have to add a couple circular "waves" to the seal to allow a little flex. This method should be able to handle all the heat you give it.
      You may have to add another flex joint to the piston to account for the small sideways movement.
      Just a thought!

  • @conceptautohouse141
    @conceptautohouse141 11 หลายเดือนก่อน +4

    Viton diaphragm material, its designed for heat/harsh enviroments. Turbo wastegate diaphrams use it orange colour with impregnated fabric, looks like the silicone version.

  • @MoonMoon-gu2ge
    @MoonMoon-gu2ge 11 หลายเดือนก่อน +1

    Iteration is the name of the game, excellent work mate can't wait to see more progress.

  • @ptonpc
    @ptonpc 11 หลายเดือนก่อน

    I was impressed by the last iteration on the seal.

  • @perrymattes4285
    @perrymattes4285 11 หลายเดือนก่อน +2

    I really admire your creativity

  • @albertglej770
    @albertglej770 11 หลายเดือนก่อน +2

    My God. Although I don't understand anything about physics and mechanics of this machine (compression ratios etc.) I think that what you do is an amazing piece of work. There should be some way to support you so you can get more time and tools to do your projects. I think that there would be a lot of people who would like to donate you few cents :)

    • @albertglej770
      @albertglej770 11 หลายเดือนก่อน

      Maybe could you please explain some science and math behind your project? It would be insteresting. Thank you for your work ❤

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน +2

      @@albertglej770 I probably wouldn't be the best person for that : ) I am a layman who works to rules of thumb, high level analysis of successful machines and experimentation. Thankfully there are individuals that help me out on that front! Cheers

    • @perrymattes4285
      @perrymattes4285 11 หลายเดือนก่อน

      Shane you say layman your calling is Engineer

  • @kreynolds1123
    @kreynolds1123 11 หลายเดือนก่อน +1

    Im excited to see you try it as a heat pump.

  • @sigmawarrior.fokeryou
    @sigmawarrior.fokeryou 11 หลายเดือนก่อน +2

    Hello Shane. I believe the leaks tampered your power test. Looking at the damaged parts up to now, I believe rubber has no place in this hot side. Aparently, the high temperature silicone used as resin for the first fiberglass fabric held better. Maybe you can try sandwich 3 or 4 layers of that fiberglass fabric with high temp silicone, and in the top, put the cotton fabric. Just keep enough slack in the fiberglass so it's not pulled by the stroke of the engine.
    Another possible option was pointed in part 8's comments, as a guy suggested to make the hot side with a more traditional cylinder/piston aproach. The problem I see with this is just making the volume of this cylinder quite right to match the cold side diaphragm.
    To get some serious power, I believe you'll have to run pressurized. When you manage to seal the engine, would be great to run tests with different pressures.

    • @sigmawarrior.fokeryou
      @sigmawarrior.fokeryou 11 หลายเดือนก่อน

      Idea for a economizer: you can "box" maybe 25cm of the piping leading the gases to the cold side, right after they leave the furnacle. Than, pour molten alluminum to fill all the space between the tubes in this 25cm lenght of the box, them put a descent heat insulation arround it (good ammount of fiberglass wool wraped with thermotape).

  • @samheasmanwhite
    @samheasmanwhite 11 หลายเดือนก่อน

    Cloth backing is absolutely the way to go! The thinner the rubber the better in this case.
    If you take a look at how turbo wastegate diaphragms are constructed you will see a similar construction and I think that is basically what you want to aim for eventually. Non-bonded cloth should be great short-term for testing though. I think the proper diaphragms are usually made by vulcanising the rubber after or while the cloth is being squished into it, but you might be able to approximate that using silicone glue to attach cloth to a thin rubber or silicone layer. Maybe just the right sort of silicone glue smeared between 2 cloth layers could be enough?
    The diaphragm also seems to be getting inverted by vacuum sometimes, I think that's just a non-return valve problem but you might want to add a little additional pressure to help out since it's a lot of extra bending that you can avoid. Also, stirling engines get more efficient at higher pressures, not sure if you want to chase that but it seems like you could with the right diaphragms :)
    Why is the exchanger section next to the furnace not insulated? I'm not that knowledgeable on stirling design but I thought it would be better if some length of it was used as a regenerator which would allow the hot end to retain more heat. I guess with the diaphragm not being separated by an insulating piston you might need to tune that insulation to avoid overheating the rubber.

  • @joelsoncdma
    @joelsoncdma 10 หลายเดือนก่อน

    It's very good to see your triall a lot of way to improve this engine....my suggestion is to use big metal piston with two rings (heat resistant fabric in midle) and use pipe to connect The cylinder to prevent heat conduct.
    I like alpha using concret your made.

  • @skysurferuk
    @skysurferuk 11 หลายเดือนก่อน +1

    0:50 That looks like Hyperlon, an incredibly tough material.. Tubes on R.I.B.s are made of this, & can withstand really hot direct sunshine for decades, so something is amiss with your machine. A great project, been following you for a while. 👍

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      You might be right! I may have misquoted what this was. The engine does get really hot : )

  • @johnwynne-qx6br
    @johnwynne-qx6br 11 หลายเดือนก่อน +1

    Brilliant, you will get there in the end. Good luck

  • @takeguess
    @takeguess 11 หลายเดือนก่อน +6

    I love the design. I am a mechanical and electrical engineer and I am very impressed. You are a better designer than several of the engineers I know... Sad but true. Being book smart doesn't make you a good engineer. Designing, building and testing with good methods is the true test of an engineer and you passed all three of those! Keep up the good work.

  • @IronGoober
    @IronGoober 11 หลายเดือนก่อน

    I believe that if you go to a thinner sheet of material(s) you will have more success, especially with the rubber. This will do 2 things, it will allow the rubber to stay cooler (heat doesn't flow well through it, so the thinner the better) and it will keep the stress lower so it won't fracture. Just like bows for arrows, you need to keep it very thin if it is going to be bending a long way. Some sort of active cooling on the diaphragm might also be beneficial. It might decrease power, but I doubt it would decrease the power that much.
    This is such a fun series to watch, thank you for sharing all of your hard work!

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Thank You for your advice, I think I will try this, many thanks : )

  • @MrDerbee
    @MrDerbee 11 หลายเดือนก่อน +2

    Keep on experimenting; remember Edison and his electric light bulb. Seems he tried hundreds of different materials for the filament before hitting on carbonized bamboo.
    45 watts looks promising!

  • @charleselertii6187
    @charleselertii6187 11 หลายเดือนก่อน

    Thank you Shane!
    -chuck in Florida.

  • @ronmoore6598
    @ronmoore6598 11 หลายเดือนก่อน +1

    Always fun to watch! Thanks for posting Keep up the good work!

  • @nicolaswolf6045
    @nicolaswolf6045 11 หลายเดือนก่อน

    Bicycle tires could be used as belows but they would need to be the right size to be pressed by the engine gasket ring, the mobile disk that connects to the crank should be bigger as well to be able to hold the tire from the other lip cilindrcal bellows instead of a flat one, tgey already come with fibers inside too, still who knows if they can tolerate the temperature, the crank arms woul need to be moved out probably...
    Thanks a lot for the videos, always glad to see each update and all the changes and adjustments!

  • @charliepearce8767
    @charliepearce8767 11 หลายเดือนก่อน

    Well done. I take my hat off to you sir !

  • @8ank3r
    @8ank3r 11 หลายเดือนก่อน +1

    Love this project

  • @gasonthebrain3738
    @gasonthebrain3738 11 หลายเดือนก่อน

    Hi Shane. Good to hear you are not to distraught over the results. I was thinking you would get a bit more power than that. I have a thought about your gasket/seals. Not what they are made from, but how they are utilised. To reduce the amount of stretch on the diaphragms, try positioning the piston or the cylinder support side, so you have an equal amount of movement either side of the central position. So to put numbers on it to add clarity, instead of having it push out 1 1/2” and then going back 1 1/2” to start again, try setting it up so it only has to move 3/4” out then back past center and then 3/4” in, then back to center to start again. Just a thought. I’m enjoying watching the videos. Thanks. Regards. Stephen.

  • @Joewho99
    @Joewho99 11 หลายเดือนก่อน +2

    A parallel linkage on pstons so the top or bottom of piston seal cannot move stretch more than sides . All your rips holes seem to be on top or bottom . Its just an isea I had while watching your latest video . Keep up the good work very interesting watching your builds .

  • @cornwallav8r
    @cornwallav8r 11 หลายเดือนก่อน

    Great progress. I agree with others, you're expecting too much from materials to flex them heavily repeatedly. Maybe a bellows configuration like on a rear axle boot configuration, or switch to some sort of piston/cylinder arrangement for longer durability.

  • @spherebotics
    @spherebotics 11 หลายเดือนก่อน +10

    I think you're asking too much of the rubber. Some kind of accordion stack or book bellows might last a lot longer.

    • @calvingreene90
      @calvingreene90 11 หลายเดือนก่อน +3

      A thin steel bellows arrangement; something not too dissimilar to what they tried with articulated boiler locomotives. This application doesn't have the grit that caused the failure in the steam locomotives.

    • @ralphpremici7632
      @ralphpremici7632 11 หลายเดือนก่อน

      👍

    • @EnergyGetter
      @EnergyGetter 11 หลายเดือนก่อน

      Yes, metal bellows should be reliable sooution.

  • @ngavigan
    @ngavigan 11 หลายเดือนก่อน +2

    The cooling fan you installed to move cold air over the cold end is quite large. I would imagine it is soaking up far more than 45watts (consider what power of electric motor you would need to run it at 500rpm). Could the fan be reduced in size and still be effective?

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Fair point! I could quickly remove it when I try again to see the difference, cheers

    • @davepennington3573
      @davepennington3573 11 หลายเดือนก่อน

      @@ShanePomeroy if you made the cool end into a water heater you could honestly add that energy to your output. There's even more waste heat available in the chimney.
      Brilliant work so far, far better than most. Measuring actual power output! What a concept. Many youtube engines spin like mad and their inventors get lots of clicks without measuring anything useful.

    • @ngavigan
      @ngavigan 11 หลายเดือนก่อน

      Even better still, have the draw air for the fire being pulled through the cool side. This will provide cooling while recycling the heat back into the firebox.@@davepennington3573

    • @ngavigan
      @ngavigan 11 หลายเดือนก่อน

      Second thoughts - the draw air flow is probably far too little to keep the fins cool, but it could do a portion of it, drawing heat from the section nearest the hot heat exchanger.

  • @PALM311
    @PALM311 11 หลายเดือนก่อน

    Although expensive welding cloth has a temperature rating of 1000°F and is really strong And perhaps a set up like that with a Bellows as we stated earlier in the comments may prevent holes from forming. you’re gaining and your patience is unrivaled! Lol.
    Really enjoy your videos. Looking forward to the next.
    Also, as a sidenote, polyethylene fabric is the strongest fabric known today, and may prevent tears and holes from forming.

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      I shall look into those blankets, cheers

  • @RingingResonance
    @RingingResonance 11 หลายเดือนก่อน

    Maybe you could add a double check valve system that makes the air circulate through the heat exchanger rather than in and out? That might help increase the power output. For the hot-side piston/seal, maybe it's worth it to use a different approach?

  • @TheKlink
    @TheKlink 11 หลายเดือนก่อน +1

    could you seal the cement with waterglass?

  • @miguelangelgalisteosanchez5045
    @miguelangelgalisteosanchez5045 11 หลายเดือนก่อน

    Hello Shane, prueba con los flancos de un neumático blando, que tenga la medida apropiada, sigue con ello, te ánimo a que sigas con el proyecto al final lo conseguirás, cheers.

  • @EngineVids
    @EngineVids 11 หลายเดือนก่อน

    The best design ive seen is on robinson stirling engines, though they dont run at high speed - maybe if they were balanced with a stove like on this they could be more efficient 🤔😎

  • @mike65120
    @mike65120 3 หลายเดือนก่อน

    I'm just watching all the videos with great interest. In the last one where you noted that the cement "bowl" inside was cracking I thought - why cement? Why not shape that "bowl" with metal with insulation behind it? :) :)

  • @ET_AYY_LMAO
    @ET_AYY_LMAO 11 หลายเดือนก่อน +1

    Maybe make your own composite, glue some fiberglass to the rubber, that might keep it from tearing?

  • @jamesharris5158
    @jamesharris5158 11 หลายเดือนก่อน +1

    Silicone sealant can be thinned with white spirit. I wonder if painting multiple layers of this mixture onto cotton cloth could create a suitable material for your seals?

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      I tried a single coating on cloth. It was OK for a few hours but then started breaking down. The cold side worked fine

    • @jamesharris5158
      @jamesharris5158 11 หลายเดือนก่อน

      @@ShanePomeroy That's a shame, I can't think of anything else that will maintain the flexibility with a higher operating temperature than silicone. Have you measured the temperature at that point (sorry, I haven't had a lot of spare time recently so I haven't been following along in enough detail to have seen if you'd shown it already in the video series).

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      @@jamesharris5158 not measured yet. I'd really like to know the temp : ). I'm currently trying multiple fabrics laminated with silicone, cheers

  • @Rose-f2t
    @Rose-f2t 11 หลายเดือนก่อน +1

    Great video. I think you are going to have to design a piston and rings for the hot side 🤕

  • @PKMartin
    @PKMartin 11 หลายเดือนก่อน

    Perhaps the flexible seal would work better with an oversized disc as the outermost layer, attached around the edge to a ring with it's inner edge sealed to the cylinder head giving a sort of flying saucer shaped single bellow?

  • @grandpaseed
    @grandpaseed 11 หลายเดือนก่อน +1

    maybe a water jacket on the hot end around the diaphragm mounting area to keep it at around 100c ?

    • @perrymattes4285
      @perrymattes4285 11 หลายเดือนก่อน

      Also make the rubber diaphram two layers with water between

  • @DIeem2042
    @DIeem2042 11 หลายเดือนก่อน

    Love the work you do. You keep chugging along with persistance! Have you tried high tensile hemp cloth? Mabe vaccum bag impregnated with high temp silicone. Also, some kind of billow fold techniques might have been perfected in the old days. Cheers

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน +1

      I never considered hemp cloth! A vacuum bag could be useful. I've just siliconed some cloth together and I do have aur bubbles. Thanks for the ideas : )

  • @redmorphius
    @redmorphius 11 หลายเดือนก่อน

    Parallel linkages is what you need

  • @MrSquishedsquashed
    @MrSquishedsquashed 11 หลายเดือนก่อน

    Do you have the working fluid at any degree of static pressure?
    In commercial Stirling Cryocoolers (which are just stirling engines used backwards) the working fluid is kept at high pressure and it makes the system much more efficient.

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      No pressure, I'm not sure the seals would take it : )

  • @ralphpremici7632
    @ralphpremici7632 11 หลายเดือนก่อน

    Have an induction coil heating it and a 10kw axilflux alternator as the flywheel.

  • @rockcrusher4636
    @rockcrusher4636 11 หลายเดือนก่อน

    Hello again, in the middle of the piston where you have it welded, I believe that needs to be able to swivel rotate because as it is now your not going straight in and out. I recommended carbon fiber, was that not a good choice for some reason. Cheers.

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Hello, I was trying to cut down on swithel points but you could be right. No, haven't tried carbon fibre yet. Do you think it will fatigue like glass cloth?I've no experience with it, cheers

    • @rockcrusher4636
      @rockcrusher4636 11 หลายเดือนก่อน +1

      @@ShanePomeroy I don't know about the carbon fiber, it was just a thought. Two things though, I think you have too many sharp corners that are cutting into the edges of the diaphragm, then I think you need to drill a hole and insert like a cheap chimney thermometer so you can see how hot that diaphragm is getting. Then if it's too hot maybe water cooling or fins around that connection before the diaphragm. Great project, and still the best I've seen. Cheers.

  • @andrewcornell2157
    @andrewcornell2157 11 หลายเดือนก่อน +1

    Why not put a equal length pantograph system to guide the pistons.

  • @oe5504
    @oe5504 11 หลายเดือนก่อน +3

    Have you considered using asbestos cloth?

    • @bigmouthstrikesagain4056
      @bigmouthstrikesagain4056 11 หลายเดือนก่อน

      Or silicone mixed with graphene, or possibly some sort of water cooling system to keep the bellows cool?

    • @oe5504
      @oe5504 11 หลายเดือนก่อน +1

      @@bigmouthstrikesagain4056 As far as I know graphene has high thermal conductivity . wouldn't that just make it worse ? Water cooling system would be too heavy ?

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Just googled that. Yes it might work but graphene still seems a little unavailable to the public at the moment. The water cooling is an option as long as the weights kept down. Many thanks

  • @egidijuskilinskas4583
    @egidijuskilinskas4583 11 หลายเดือนก่อน

    Have you tried aramid cloth? Its quite resistant to rubbishg

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      I shall take a look, many thanks

  • @donwright3427
    @donwright3427 11 หลายเดือนก่อน +1

    Maybe just cotton cloth dipped in silicone and acetone mix then molded to a bellow shape? Or Teflon piston on the hot end?

  • @mickellis8747
    @mickellis8747 11 หลายเดือนก่อน +1

    I think you could use silicone insertion rubber on the hot side diaphragm. It would be more durable than anything you have used so far.

  • @danp1224
    @danp1224 11 หลายเดือนก่อน

    What about some ovenproof silicone baking trays

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      It might end up being something like this, perhaps along with supporting material, cheers

  • @Red9GearHead
    @Red9GearHead 11 หลายเดือนก่อน +1

    You may have already tried… Use your silicone and napha mixture to soak the fire blanket. Rather than just painting it on, and allowing the silicone to cure with the fire blanket encased.

  • @dirgethesergal319
    @dirgethesergal319 11 หลายเดือนก่อน

    might be time to have a look at silicone seals again but with the support of the fibreglass and canvas, looking good so far though. you can see how much progress you have made with the designs when you look back at the first engine

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน +1

      You could be right : ). I'm doing a few experiments at the moment to see how much heat is transfered through various layers of glass cloth, cheers

  • @philhermetic
    @philhermetic 11 หลายเดือนก่อน

    From a quick glance there would seem to be a lot more than 40W keeping all that metal in rapid motion. I assume you are making 40W more than it takes to run the machine?
    Phil

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Yes , 45w output

    • @philhermetic
      @philhermetic 11 หลายเดือนก่อน +1

      @@ShanePomeroy could you possibly take of the flywheel and replace it with a generator and load the generator electrically till it stalled?

  • @trevortrevortsr2
    @trevortrevortsr2 11 หลายเดือนก่อน

    Trying to make a flexible seal in a dry hot environment - metallic foil seals go up to 400c - I guess that's why Stirling focused on the displacer-type engine.

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      I think you've hit the nail on the head with the Stirling brothers. I was hoping modern materials might overcome issues ! We're see!

  • @jasonburguess
    @jasonburguess 11 หลายเดือนก่อน

    A solid piston in a cylinder like a v twin air compressor head is a better bet, flexible seals simply won't work long term in this application. Solid pistons in a sealed cylinder with a cylinder head will definitely work better.

  • @MakinNbreakin
    @MakinNbreakin 11 หลายเดือนก่อน

    Kevlar?

  • @ivankovac7844
    @ivankovac7844 11 หลายเดือนก่อน

    The performance would probably be increased by puting a regenetator box halfway between the hot and cold side. Also, a multi-layer diaphragm is the way to go, but with cloth like/non expandable materials. The diaphragm should bend but not expand. Measuring the top dead and bottom dead points of the stroke and designing a diaphragm based on that displacement would be the way to go

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Sound advice, many thanks. I'll adjust the strokes to minimise the dead space when pistons are compressed (material stretched out), cheers

  • @Skoda130
    @Skoda130 10 หลายเดือนก่อน

    You need a solid piston on the hot side. There are no flexible materials that can handle these conditions.

  • @coondelboory9936
    @coondelboory9936 11 หลายเดือนก่อน

    Great!

  • @jltheboss
    @jltheboss 11 หลายเดือนก่อน

    Use leather instead of rubber it can handle heat better

  • @ethanlawson4658
    @ethanlawson4658 11 หลายเดือนก่อน

    Why are you building a Stirling Engine when a boiler with a Turgo turbine is more efficient, cheaper, and is easier to build and maintain? I'm just curious.

  • @MaxCarponera
    @MaxCarponera 11 หลายเดือนก่อน

    45W it's not a small feat. You must scale it, make it 10x bigger. Then will be talking.

  • @eliopineda8779
    @eliopineda8779 8 หลายเดือนก่อน

    Mi hermano Usted es un mostro, yo estoy tratando de escribirte y contactarte para saber si nos puedes ayudar desde Panamá 🇵🇦👍 Bendiciones....

  • @TrueHelpTV
    @TrueHelpTV 11 หลายเดือนก่อน

    gotta internalize that piston brother.. to much lost energy in the expansion, and inability to compress.

  • @ralphpremici7632
    @ralphpremici7632 11 หลายเดือนก่อน

    👍👍👍

  • @johngillon6969
    @johngillon6969 11 หลายเดือนก่อน +1

    have you considered good old pig skin, like they made footballs. they seem to last forever.

  • @johnshearing
    @johnshearing 11 หลายเดือนก่อน

    The strings on your clothing near the flywheel make me nervous. Please take care.❤

    • @ShanePomeroy
      @ShanePomeroy  11 หลายเดือนก่อน

      Good point, I'll be more carefully: )

  • @gadellatypov63
    @gadellatypov63 11 หลายเดือนก่อน

    Ты на эластичной мембране имеешь большие потери. Сделай ее из пластичного, но не эластичного материала

  • @icebluscorpion
    @icebluscorpion 11 หลายเดือนก่อน

    45 watts😅 that thing looks like a toy no woanders you get that little power 😂 Stirling motors work with high pressure and water cooled cold side. Also the less heat creap you have in the Stirling the higher the efficiency

  • @kevinroberts781
    @kevinroberts781 11 หลายเดือนก่อน

    Use leather

  • @tulsatime-_-
    @tulsatime-_- 9 หลายเดือนก่อน +1

    Try a toilet plunger

    • @ShanePomeroy
      @ShanePomeroy  9 หลายเดือนก่อน

      Love the out the box thinking : )

  • @Bigredkarl
    @Bigredkarl 7 วันที่ผ่านมา

    sweater strings and machinery dont mix

  • @АнтонОстроконь-б8р
    @АнтонОстроконь-б8р 11 หลายเดือนก่อน

    Единственное решение; - применить гофрированную манжету из нержавейки!

  • @bussi7859
    @bussi7859 11 หลายเดือนก่อน

    Crap