3D printed silencer/air stripper

Discussion in 'General Airgun Chat' started by Brian.Samson, Dec 20, 2013.

  1. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    My Wegu spacer came out really well.. so now I'm working on a butt hook (better and ALOT cheaper than the Gemini) and for a bit of fun I've just designed a new type of Silencer.

    I wanted a silencer that also acts as an airstripper with no moving parts (like springs etc) inside. and I'm designing it specifically for the Walther LGV.

    The idea (plucked from thin air with no real science behind it) is to use a variable pitch internal helix with the ratio of sectional volumes based loosely on the Golden Ratio ( Phi ). Hence my daft name for it - a 'Phi-Lencer' :D

    I figured if it's good enough for nature, it's a good enough starting point for a silencer.

    Not had it printed yet - but priced it out at about £12 to have printed (actually £8.80, but minimum order works out at £24 inc vat and delivery so if I print 2 they'll cost about £12 each).

    Unfortunately I'm not allowed by law to sell them because I'd need to be an RFD, but I thought you might be interested in seeing what it looks like. I've rendered it in transparent green so you get the idea about what's inside and then in black so you can see what it'll actually look like.

    It's fairly small - only 27mm diameter and about 100mm long

    I just need someone with a 1/2 UNF Tap set to tap the hole for me when I get it printed. Anyone got a set of 1/2 UNF taps? - it'll need a blind tap because of the proximity of the stripper cone - the hole is already created at 29/64" (11.5mm) ready for the tap.
     

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  2. Charlts

    Charlts Getting dusty

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    Looks awesome Bri, of course there's nothing against the law with you selling the plans or distributing them freely amongst people you know.:) ;)
     
  3. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    There's been a fair few press horror stories about people being able to 3D print guns which is largely just media hype and bullshit, but I guess this is a fairly interesting way to get round the law on selling silencers... All you'd need to do is send the STL file for this design to a 3D Print agency (and call it an air flow restrictor or something) and for about £24 you could have 2 of them :D

    The thing I like most about this design is that it's printed as a single part, so you couldn't actually make this part on a CNC machine/ lathe and milling machine, you'd have to make it in several parts.

    I've gone for a 4.8mm hole as a starting point (obviously .177 only :D) and the internal volume would probably only suit a springer, it would need more volume for a PCP I'd imagine.

    I know very little about silencer design btw, just having a play and making some assumptions (which might be wrong)
     
  4. johnnytopshot

    johnnytopshot New Member

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    Pro Target Triple Stripper

    Hi Brian

    What company are you using to print your designs?
    Just for fun, I designed this one piece triple stripper for a Pro Taget (to fit inside the shroud), it is a similar size to your design but the cheapest quote I could get was about £80

    Triple Air Stripper.jpg Triple Air Stripper Section.jpg
     
  5. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I'm using http://www.3dprint-uk.co.uk/

    10p per cubic cm based on total swept volume.
    They've been excellent so far and I've probably done half a dozen orders so far.

    The part strength is much stronger than I was expecting too.
     
  6. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    That looks cool!

    What gap sizes did you go for before the entrance to the cones and what diameter is the bore?
    I guessed at about 5mm gap and a 4.8mm bore for the Philencer.. I think I'm going to add a series of small holes after the cone on mine. The thinking is that the air travelling over the cone will cause a bit of turbulence and an area of low pressure air on the back of the cone which I can use to draw some more air out from behind the pellet through the holes (I've yet to add).

    I have no idea what the hell I'm doing of course, but it's fun to have a play with some theories :)
     
  7. SDplinker

    SDplinker Pellet testing...yawn

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    tremendous work Brian. This is really the way of the future for small parts. As the technology evolves I could see more and more parts of a rifle made this way.

    Have you ever ordered a part in metal? I wanted to do some harmonics testing with my Steyr with a simple tube that I could slide up and down the end of the barrel. Just a big tube - open ends, no air stripping. But a machinist wants at least $50 for this. Seems like a 3D printed part would be a piece of cake.
     
  8. zahed2010

    zahed2010 Member

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    Definitely would be interested in this...
     
  9. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Hi Casey

    I haven't found a cheap 3D printing service that will do metal - you'd definitely be paying more that $50 to have something printed in metal.. there are companies that will do it, you can even have stuff printed in Titanium ( if you've got deep enough pockets! :D ). Give it a few years and I'm sure decent quality 3D printers will be as common in the home as laser printers are now. When that happens, I'm sure the price of printing in metal through agencies will drop massively too.

    You can pick up Styer barrel weights for a bit of harmonics testing - I'm sure I bought one for about £15 a few years ago from Harry Preston (Styer UK)
     
  10. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    There's quite a few individual parts involved in what I have in mind, at least a dozen, but it'll be as adjustable as the Gemini, in fact it'll be easier to adjust because the fine tuning will be able to be done without dismantling bits of it to get to other bits (like you currently have to do on the Gemini). I've also come up with a different take on the actual hook itself to help accommodate shooting at elevated targets and provide more stability on all other shots.

    You'll be able to swap components out and add components too - so for example, the extra links you can buy for the Gemini to extend it will cost about £2 to print from the agency I currently use, so you could add as many as you like without breaking the bank.

    I've attached a rendering of a couple of test parts (how they'd look in Aluminium) but I'm still refining the shape and tolerances between moving parts, so it probably won't look like this when it's finished.
     

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  11. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    The 3D print for the butt hook bits came back today, well pleased with them. Obviously won't look quite as good as something made on a CNC machine, but it's not bad at all for a 3D print.
     

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  12. zahed2010

    zahed2010 Member

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    What program do you use to design the parts Brian?
     
  13. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I'm using Solidworks 2013 and Keyshot to do the rendering for photorealistic piccys.

    I have very little experience of 3D design, I downloaded a series of training video's on Solidworks and it took me a couple of evenings to watch the videos (from Lynda.com) and learn how to use it.

    There's loads of training videos on YouTube for Solidworks as well. I'm getting much faster with it now, the Silencer design took me a couple of hours sat on the sofa while the other half watched some drivel on the TV - X-Factor or something dismal like that :D

    Solidworks also comes with a flow analysis addon, so I had a play with that last night and I've altered the design to improve airflow now. Pretty cool that you can simulate air flow and get an idea about velocities.

    AutoDesk Inventor gets some good reviews too. I picked Solidworks because it was very reasonably priced ;) and I found some training videos that were also very reasonably priced too ;)
     
    Last edited: Dec 21, 2013
  14. RobF

    RobF Administrator Staff Member

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    What's the strength like Brian. Will it take the compression of the bolts on the butt plate and resist them turning?
     
  15. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I'm really impressed Rob, the accuracy of the print is extremely good. The aerotight nuts fit in perfectly, so well in fact that you would need to use a longer bolt to push them back out again, there's no way they'll just fall out.

    I wanted the parts to be able to move but not too freely, so I designed in a 0.15mm clearance. Everything fits perfectly, the M4 cap screws, washer and aerotight nuts - all a nice tight fit exactly as I designed them.

    So with very little torque on the bolt the parts are extremely solid - you'd snap the part before the hinged parts moved. I could put a fair bit of torque on the bolts before anything would snap I reckon and everything is rock solid. Much more solid than the home made aluminium butt hook I've got on my rifle at the moment.

    The surface finish (as you can probably see by zooming in a bit on the photo's) is a bit like an Extra Strong mint, but this works really well for giving a bit of grip in the shoulder.

    I'm so impressed with the strength I reckon I'll be able to get away with 3D printing the hook part.

    I've found that the best way to colour the parts now is to use 'Rit' dye, although black ends up coming out with a very slight brown tinge to it. I feel a multicoloured 'Lego' look butt hook coming on :D
     
  16. Mildot

    Mildot New Member

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    Sidewheel, please :)
     
  17. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I probably won't be making a sidewheel, well at least not until I've got my own printer (I'm still waiting for the FormLabs 1 to be released and reviewed by real users)

    The reason is it wouldn't be significantly cheaper than the excellent sidewheels you can already buy - Jon Harris, Barry Taylor, Rowen etc.

    The pricing works on total swept volume, so a 120mm sidewheel that was say 10mm thick would cost out as (3DPrint UK add 1mm to each side for clearance of other parts being printed at the same time so 120 becomes 120+1+1)

    122 x 122 x 12 / 1000 x 0.10 = £17.86 ex VAT. By the time you've added vat and £6 delivery you're not far off £30 and you can buy a really nice aluminium wheel for around £50 anyway.

    I'm concentrating on stuff you can't currently buy or stuff you can make much cheaper. Gemini butt hook would set you back around £370.. I reckon I can design and print all the bits for around £70.
     
  18. dnic

    dnic Share the Love

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    Brian,

    Amazing post, very enjoyable read and comments from other members. I wonder if it is too late to ask Santa for a 3D printer, I want one.

    Looking forward to reading your further design and printing projects.

    David
     
  19. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Thanks David

    I know I must be boring everyone with all my 3D printing posts :D
    I just think it's so cool that I've got to tell someone.. hopefully when 3D printers become a common desktop item in the home, I'll have a big collection of designs shooters from all over the world will be able to download and print for themselves.

    If you're thinking about buying a printer, just be aware that these prints have been made on a very very expensive industrial machine. The printers you can buy for a grand or so really aren't up to the job in terms of quality at the moment.

    The FormLabs1 laser printer (due out in March) might well be upto the quality, but there's a question mark over strength, oh and they're about $3500.

    Prices will drop though and quality will go up and that will happen pretty quickly I reckon.
     
  20. palmanda

    palmanda Member

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    Very interetsing, looks like this could be the future of small part manufacturing :)
     

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