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  • Have Blue [dot org] » We hold these truths to be self-evident, that not all ABS is created equal
    designation CYCOLAC ABS MG94 NA1000 from General Electrics Co Pittsfield Mass I d recommend reading the rest of the patent It talks about optimum extrusion temperatures degradation of the ABS at high temperatures and compares the modified ABS with standard ABS The summary is that standard ABS exhibits non Newtonian flow which limits the response time of the print head It requires higher pressure to get the ABS to flow initially then once flowing pressure is reduced The modified ABS apparently performs better in this respect There s no mention of the silicone vs toothpaste characteristic but it s quite possible that it also varies between modified and standard ABS NIP will apparently extrude customer supplied polymers so I reckon the best bet would be to buy some of the Cycolac MG94 from these guys http catalog ides com datasheet aspx I 28365 E 57277 have it delivered to NIP get it extruded and see if it behaves the same as the Stratasys material Reply Have Blue said 2010 08 19 22 35 Nophead I played a little more with the ABS today and brought it down to as low as 230 C 235 C seems to be about the best compromise temperature as far as trying to get straight filaments in the crosshatch infill Good insight regarding post extrusion swell I ll have to see if I can mic some NIP and Stratasys filaments to see how they compare Jeff I wholeheartedly agree that perhaps reprap should try to find a particular grade of ABS to work with as a baseline or at least acknowledge the limitations of generic ABS The Stratasys ABS has me downright spoiled and I m getting more and more aggravated with the NIP ABS not a slight against NIP in any way they provided exactly what was asked for and I ll definitely be seeing what other formulations they can do I m quite simply amazed at what nophead and the others have been able to do with such an unruly temperamental material that warps and lifts corners with no provocation the annoyance is not something I d want to subject reprap newbies to as the material looks to have a major impact on resulting part quality The more I struggle the better a deal the Stratasys material prices look I just started reading through the patent application you found and it looks to be an excellent resource I did do some digging through ides com today looking for ABS resin suppliers and tried matching up material specs of the Stratasys P400 ABS with various offerings The 20090295032 patent application notes Dow AG700 ABS as the comparative material and AG700 looks to be fairly similar in properties to the Stratasys P400 ABS My own searching led to me to believe that Dow was the supplier of ABS resin to Stratasys specifically an F 2000 ABS resin that I ve been able to find no further information on so this is certainly supporting evidence Additionally the AG700 ABS is described as lowest gloss of the Magnum ABS resins which definitely matches the lobster red Stratasys P400 ABS I had been using the NIP ABS has been much shinier in appearance Beyond the AG700 ABS the MG94 NA1000 ABS sounds very interesting and I ll certainly have to look into getting some as well as the AG700 naturally Nophead do you think existing reprap extruders would be able to get up to the temperatures that the MG94 NA1000 ABS appears to like Reply Jeff said 2010 08 20 07 56 The patent seems to be saying Look how good the modified mg94 is compared to the standard ag700 so are you sure it s not what Stratasys are using If I were you I d aim straight for the mg94 Reply Have Blue said 2010 08 20 09 30 I d actually like to start with the AG700 first as I want a drop in replacement for the P400 ABS my Stratasys machine uses so I can be back to making usable parts The old software that drives my FDM 1600 has no information on these much newer materials which were never supported for the 1600 anyhow so I d have to do a bunch of hacking and experimentation to modify the definition files to run MG94 happily this would have been my next step with the generic ABS had I not decided to look at alternate materials Don t get me wrong I really want to try the MG94 as well but myself and other old Stratasys owners would like a cheap P400 clone as a first step and baseline material However we may be limited by minimum order quantities in the end I don t know if Dow or SABIC would be willing to sell resin in anything less than a 2000 lb load I called Donna at NIP this morning and talked to her about the ABS she said that the material Jim gets is just a generic ABS grade and works well for plastic welding but if we have material specs and or MSDS sheets for alternate materials they can see about acquiring it I emailed her the sheets that I was able to dig up on the AG700 and MG94 so hopefully she and Jim can contact their suppliers and see what our chances are of getting our hands on either material Reply Have Blue said 2010 08 20 20 26 Jeff I did some more digging to try and see if MG94 has actually been used by Stratasys yet or if the patent application merely hinted at an upcoming material and it looks like MG94 is a dead ringer for the Stratasys ABS M30 material I found other methyl methacrylate modified ABS MABS resins as well such as BASF s Terlux materials I was rather amazed to read in Integrated product and process development methods tools and technologies that Stratasys announced the addition of MABS methyl methacrylate ABS to the family of modeling materials available for use with the FDM 1600 in November 1995 My immediate reaction was whaaa Apparently they are referring to P500 ABS which Stratasys referred to as Medical ABS as it could be sterilized with gamma radiation which they now refer to as ABSi Quickslice 6 4 doesn t have an option for P500 on the FDM 1600 but it does show up for the FDM 1650 I ll have to dig through the definition files and see how different P500 and P400 tables are My bigger question at this point is how does ABSi differ from ABS M30 Reply Jeff said 2010 08 20 20 27 I see I hadn t realised that mg94 was such a new development for stratasys I suppose it must be given the patent was issued in 2009 I ll shut up and let you experiment Reply Have Blue said 2010 08 20 20 33 Jeff I hope you do not shut up Your information led me to investigate further and reconsider being rather conservative in looking at new materials hey I ve already run generic ABS through my machine so what could MG94 hurt Reply Jeff said 2010 08 20 20 35 and I posted that before reading your last comment The plot thickens I suppose it s possible that ABSi and m30 are the same Reply Have Blue said 2010 08 20 20 40 Precisely what I m wondering so we ll have to see how the two spec sheets and MSDS sheets compare This certainly gets interesting Reply Erik de Bruijn said 2010 08 21 15 02 You re really digging into this I don t have much to add but this If you could modify the toolpath and feedrates this would allow you to have more control and still work with various polymers Since you ve found it to be an off the shelf motion control system with an insuccesfully obfusicated protocol you could write a postprocessor for Keep in mind that a polymer made of 3 monomers will show different properties based on the ratios of the monomers that were linked to form the polymer Reply Erik de Bruijn said 2010 08 21 15 04 You re really digging into this I don t have much to add but this If you could modify the toolpath and feedrates this would allow you to have more control and still work with various polymers Since you ve found it to be an off the shelf motion control system with an insuccesfully obfusicated protocol you could write a postprocessor for one of the several toolpath generators that are there Skeinforge the RepRap Java host RepSnapper One more thing Keep in mind that a polymer made of 3 monomers will show different properties based on the ratios of the monomers that were linked to form the polymer Reply Luis bottaro said 2010 08 23 10 06 Hello I am from a Brazilian company called Cemar We have here a Stratasys Prodigy Plus machine and researching about reloading the stratasys cartridges I ended up here I did not really tested anything until now but I will do soon we are spending a lot with the originals but as a seller of prototypes we will use a similar material just in case that present real good results If I discover something for here I will let you know and I will be here to follow your great work Sincerely Luis Reply Have Blue said 2010 08 23 10 48 After a phone call to Styron it appears that the AG700 is a dead end Not because it wasn t the right resin it probably was at least at the time that the patent application was being written but because it has apparently been discontinued Not only that but Dow Styron whoever actually makes the stuff only sells to the automotive industry At least MG94 still looks to be a current product and I have an inquiry in to SABIC for the MSDS sheet In comparing the ABSi and ABS M30 sheets they do appear to be different products In looking around at ABS resins from various suppliers I m wondering exactly what material properties are desired for FDM I can t imagine that Stratasys blindy started running ABS samples through their machines looking for formulations that didn t warp or lift corners Melt flow and deflection temperature would seem like important properties but I m curious to know if the low impact noted on the AG700 sheet is important Erik I ve thought about seeing if I could come up with a postprocessor for Skeinforge but I have no idea how complex that would be my programming skills are rather limited Luis Please let me know if you discover any alternate materials that work well Reply Jeff said 2010 08 24 06 04 you re dead right it would be very helpful to know what material properties are relevant in fdm Perhaps industrial abs extrusion will shed some light on it Lots of objects are manufactured by abs extrusion eg guttering and abs must be optimised for dimensional stability of extruded profiles Of course there are more problems in fdm like layer adhesion but it might be a start Have you seen this page http www sabic ip com gepapp Plastics servlet ProductsAndServices Product series sltPolymer ABS search Search searchresults It lists a methacrylate modified abs for scratch resistance and depth of colour mg8000sr Perhaps it would be a suitable alternative to ag700 Reply Have Blue said 2010 08 24 11 01 I think high flow ABS may be what we need for RepRap Stratasys both the AG700 and MG94 appear to be high flow and such ABS materials appear to be good for molding fine detail Hmmmm fine detail That sounds exactly like what we re trying to accomplish given nozzle orifices of 0 5mm and less Not only that but high flow ABS may really cut down on the extruder difficulties that people have had not to mention increasing the speed at which material can be laid down The next question would be does high flow ABS still exhibit the warping and corner lifting seen with standard ABS grades Also of interest is the PP3DP printer being talked about in the RepRap forums The PP3DP website says that you can use Stratasys ABS on the machine so I asked in the forum for clarification on the filament diameter They said the plastic is 1 73mm which is indeed essentially Stratasys diameter However I recall seeing somewhere that they mentioned you can get greater part quality by using Stratasys filament so perhaps they re still struggling with ideal filament formulation as well They do say that plastic distribution in the US and Europe will be forthcoming so hopefully a ready supply won t be too far off Reply Have Blue said 2010 08 25 14 05 SABIC responded and I just got a copy of the MG94 MSDS sheet The NA1000 suffix turns out to be nothing more than the color number in this case NA tural The sheet looks pretty close to the ABS M30 MSDS sheet but not an exact match Still it s most likely close enough so I ll see what sort of order quantities they deal with Reply Luis bottaro said 2010 08 26 10 15 Have Blue if you need to increase your quantity we could make a combined order Let me know the price and term them we arrange the details how we can do it if its needed Reply Have Blue said 2010 08 26 10 45 I still don t know pricing yet I signed up for a customer account which should hopefully be ready to use in a few days It appears that all the pricing is online and automated so hopefully I can check out the cost of other resins as well Reply Anthony Mouse said 2010 10 28 16 54 Hi All It see this thread has been dead for a few months now That said I have a Stratasys Dimension Elite I have played with some aftermarket materials that are sold by a third party company I found that this material does not work nearly as well as the Stratasys materials I m not exactly sure what magic Stratasy has but their materials build VERY good parts Yes it s expensive but worth it to me I would love to buy cheaper materials but not at the expense of being able to build quality parts I do however have some insight for you The materials available for my machine are P400 and P430 The P430 is referred to as ABS Plus This material is noticeably stronger than the P400 Another note I have noticed that the third party materials are significantly shinier that the Stratasys materials I would be willing to bet that they are using the materials extruded by NIP The dimension Elite also uses water soluble support material This makes removing supports very simple Not sure what you have found about those materials but probably worth looking at That said it s also very expensive The newer Stratasys machines use cartridges with chips in them This makes refilling impossible unless you can figure out how to reset the chip on them Anyone have any ideas about how to do that Anyhow nice thread I plan to keep my eye on it and am happy to help you with any research Here is the MSD sheet for the P430 ABS Plus https confluence rave ac uk confluence download attachments 46596355 MSDS EU P430 ABS Plus 08 pdf Here are the material specifications for P430 http www solidimage3d com images Docs ABS Plus Properties pdf Kindest Regards ANthONY MOUSe Reply Have Blue said 2010 10 28 18 47 Hi Anthony I m pretty sure my FDM 1600 can handle the P430 as well but my software Quickslice 6 4 circa late 1999 has no knowledge of it I believe support for the material finally came with Insight v3 x in 2002 or so I ve been trying to find a copy of Insight v6 or earlier to try out but haven t found any yet and I m not about to pay 2000 to Stratasys for software support that would expire in just over a month anyhow Would you mind revealing the third party supplier s you tried Very interesting that it was also glossy material perhaps the low gloss is indeed the magic property needed for FDM As far as soluble supports there are a lot of potential materials PLA looks quite promising and is a favorite of the RepRap crowd and Johnny Russell Ultimachine com was working with NIP to try some out Johnny was also quite excited about trying out the 3801X resin from NatureWorks LLC http www natureworksllc com news and events press releases 2010 01 14 10 high heat impact grade aspx but I don t know if he s gotten to play with it yet This post certainly shows promise for PLA as a soluble support http ifeelbeta de index php support quest for support 2 I ve had a number of people ask me about refilling resetting Stratasys cartridges but as my machine predates such limitations they don t make em like they used to I have no input on the matter I d love to hack on it if I had access to such a machine though sniff the line with a digital oscilloscope and determining the communication should be pretty easy Jim NIP tells me that one of his customers has indeed figured out how to hack cartridges but he wouldn t elaborate Reply John said 2010 11 22 17 15 I m looking for P430 substitute Any news on acquiring some of the MG94 And btw the stratasys cartridges just use a serial EEPROM chip soldered to a small PCB Nothing special and not that hard to

    Original URL path: http://haveblue.org/?p=596 (2016-04-26)
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  • Have Blue [dot org] » More fun and games with plastic filament
    speed on the fly How to hold the empty spool though An expanding collet would be great but I don t have any as big as the 2 bore in the Stratasys spools A little bit of digging through scrap bins and I found a Delrin cylinder that would work perfectly for making a pair of bullnose centers mounted on a bolt Here s what the assembly with spool looks like on the mill I clamped a live center into the mill vise to support the spindle from underneath What to do on the unwind side was a bit trickier Based on my winding by hand of the ABS I knew that keeping the coil of filament in a rather static shape was very important so I opted to make a simple spool that could be assembled around the coil itself I used Masonite for the sides and drilled holes through each piece to allow for joining screws Multiple sets of holes were drilled so that I could adjust the screw locations to perfectly fill out the center of the coil The coil of HIPS filament as it arrived from NIP still bound with shrink wrap is placed onto one of the spool sides The screws that will attach the other side are placed as close to the interior diameter of the coil as possible 2 pieces of pneumatic tubing are slipped over each screw to serve as spacers The fully assembled spool mounted and ready to unwind The radial lines on the top piece of Masonite are a result of using an angle grinder to deburr the holes It may sound crazy but it worked far better than the countersink I tried first I clamped a piece of 3 4 rod in the bench vise and slipped the spool over it a collar on the rod kept the spool at an appropriate height It rotated pretty freely so I took the loose end of filament and tied it to the inside of the empty spool I set the mill spindle to the lowest speed and hit the power 60 rpm is perfectly fast for winding though I cranked the speed up to around twice that once I had a good start on the winding I held the filament in one hand with a rag so that I d actually have skin left to provide continuous tension and the material unwound from my adjustable spool just as nicely as I had hoped with no snarls About a half hour later I had two spools fully refilled This beats the heck out of doing the winding by hand I gave the NIP HIPS a try in the Stratasys noting that the Stratasys support material is slightly more brittle than the NIP HIPS I ran a small test part with NIP ABS at 250 C and the HIPS at 265 C The HIPS performed admirably and had good adhesion to the NIP ABS The part separated from the base cleanly I m

    Original URL path: http://haveblue.org/?p=635&replytocom=2530 (2016-04-26)
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  • Have Blue [dot org] » More fun and games with plastic filament
    on the fly How to hold the empty spool though An expanding collet would be great but I don t have any as big as the 2 bore in the Stratasys spools A little bit of digging through scrap bins and I found a Delrin cylinder that would work perfectly for making a pair of bullnose centers mounted on a bolt Here s what the assembly with spool looks like on the mill I clamped a live center into the mill vise to support the spindle from underneath What to do on the unwind side was a bit trickier Based on my winding by hand of the ABS I knew that keeping the coil of filament in a rather static shape was very important so I opted to make a simple spool that could be assembled around the coil itself I used Masonite for the sides and drilled holes through each piece to allow for joining screws Multiple sets of holes were drilled so that I could adjust the screw locations to perfectly fill out the center of the coil The coil of HIPS filament as it arrived from NIP still bound with shrink wrap is placed onto one of the spool sides The screws that will attach the other side are placed as close to the interior diameter of the coil as possible 2 pieces of pneumatic tubing are slipped over each screw to serve as spacers The fully assembled spool mounted and ready to unwind The radial lines on the top piece of Masonite are a result of using an angle grinder to deburr the holes It may sound crazy but it worked far better than the countersink I tried first I clamped a piece of 3 4 rod in the bench vise and slipped the spool over it a collar on the rod kept the spool at an appropriate height It rotated pretty freely so I took the loose end of filament and tied it to the inside of the empty spool I set the mill spindle to the lowest speed and hit the power 60 rpm is perfectly fast for winding though I cranked the speed up to around twice that once I had a good start on the winding I held the filament in one hand with a rag so that I d actually have skin left to provide continuous tension and the material unwound from my adjustable spool just as nicely as I had hoped with no snarls About a half hour later I had two spools fully refilled This beats the heck out of doing the winding by hand I gave the NIP HIPS a try in the Stratasys noting that the Stratasys support material is slightly more brittle than the NIP HIPS I ran a small test part with NIP ABS at 250 C and the HIPS at 265 C The HIPS performed admirably and had good adhesion to the NIP ABS The part separated from the base cleanly I m at

    Original URL path: http://haveblue.org/?p=635&replytocom=2532 (2016-04-26)
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  • Have Blue [dot org] » More fun and games with plastic filament
    speed on the fly How to hold the empty spool though An expanding collet would be great but I don t have any as big as the 2 bore in the Stratasys spools A little bit of digging through scrap bins and I found a Delrin cylinder that would work perfectly for making a pair of bullnose centers mounted on a bolt Here s what the assembly with spool looks like on the mill I clamped a live center into the mill vise to support the spindle from underneath What to do on the unwind side was a bit trickier Based on my winding by hand of the ABS I knew that keeping the coil of filament in a rather static shape was very important so I opted to make a simple spool that could be assembled around the coil itself I used Masonite for the sides and drilled holes through each piece to allow for joining screws Multiple sets of holes were drilled so that I could adjust the screw locations to perfectly fill out the center of the coil The coil of HIPS filament as it arrived from NIP still bound with shrink wrap is placed onto one of the spool sides The screws that will attach the other side are placed as close to the interior diameter of the coil as possible 2 pieces of pneumatic tubing are slipped over each screw to serve as spacers The fully assembled spool mounted and ready to unwind The radial lines on the top piece of Masonite are a result of using an angle grinder to deburr the holes It may sound crazy but it worked far better than the countersink I tried first I clamped a piece of 3 4 rod in the bench vise and slipped the spool over it a collar on the rod kept the spool at an appropriate height It rotated pretty freely so I took the loose end of filament and tied it to the inside of the empty spool I set the mill spindle to the lowest speed and hit the power 60 rpm is perfectly fast for winding though I cranked the speed up to around twice that once I had a good start on the winding I held the filament in one hand with a rag so that I d actually have skin left to provide continuous tension and the material unwound from my adjustable spool just as nicely as I had hoped with no snarls About a half hour later I had two spools fully refilled This beats the heck out of doing the winding by hand I gave the NIP HIPS a try in the Stratasys noting that the Stratasys support material is slightly more brittle than the NIP HIPS I ran a small test part with NIP ABS at 250 C and the HIPS at 265 C The HIPS performed admirably and had good adhesion to the NIP ABS The part separated from the base cleanly I m

    Original URL path: http://haveblue.org/?p=635&replytocom=2538 (2016-04-26)
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  • Have Blue [dot org] » More fun and games with plastic filament
    on the fly How to hold the empty spool though An expanding collet would be great but I don t have any as big as the 2 bore in the Stratasys spools A little bit of digging through scrap bins and I found a Delrin cylinder that would work perfectly for making a pair of bullnose centers mounted on a bolt Here s what the assembly with spool looks like on the mill I clamped a live center into the mill vise to support the spindle from underneath What to do on the unwind side was a bit trickier Based on my winding by hand of the ABS I knew that keeping the coil of filament in a rather static shape was very important so I opted to make a simple spool that could be assembled around the coil itself I used Masonite for the sides and drilled holes through each piece to allow for joining screws Multiple sets of holes were drilled so that I could adjust the screw locations to perfectly fill out the center of the coil The coil of HIPS filament as it arrived from NIP still bound with shrink wrap is placed onto one of the spool sides The screws that will attach the other side are placed as close to the interior diameter of the coil as possible 2 pieces of pneumatic tubing are slipped over each screw to serve as spacers The fully assembled spool mounted and ready to unwind The radial lines on the top piece of Masonite are a result of using an angle grinder to deburr the holes It may sound crazy but it worked far better than the countersink I tried first I clamped a piece of 3 4 rod in the bench vise and slipped the spool over it a collar on the rod kept the spool at an appropriate height It rotated pretty freely so I took the loose end of filament and tied it to the inside of the empty spool I set the mill spindle to the lowest speed and hit the power 60 rpm is perfectly fast for winding though I cranked the speed up to around twice that once I had a good start on the winding I held the filament in one hand with a rag so that I d actually have skin left to provide continuous tension and the material unwound from my adjustable spool just as nicely as I had hoped with no snarls About a half hour later I had two spools fully refilled This beats the heck out of doing the winding by hand I gave the NIP HIPS a try in the Stratasys noting that the Stratasys support material is slightly more brittle than the NIP HIPS I ran a small test part with NIP ABS at 250 C and the HIPS at 265 C The HIPS performed admirably and had good adhesion to the NIP ABS The part separated from the base cleanly I m at

    Original URL path: http://haveblue.org/?p=635&replytocom=2540 (2016-04-26)
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  • Have Blue [dot org] » Gunsmithing the RAS-12 – Part 1
    15 platform The rounded nose and rebated rim makes feeding far simpler than with a standard 12ga shotshell and allows for easy adaptation of existing magazines The most significant feature of the cartridges is obvious they are not of metal construction but polymer US patent 9109850 calls out polycarbonate and nylon as suitable materials though various online sources specifically note polycarbonate as the hull This feature alone is what made me take notice of the system given that I ve done a bit of tinkering with 3D printed polymers in gunsmithing applications Even if supplies of the original ammunition dry up cough Gyrojet cough Dardick cough EtronX cough it should still be possible to recreate the cartridges in a reverse engineered fashion I m somewhat surprised that the RAS 12 designers didn t opt to open source the design as SAAMI standardization is precisely what has allowed previously proprietary cartridges to survive in the market if not outright flourish I carefully disassembled a cartridge to determine the weights in grains for all of the components Projectile half 512 4 gr Nosecone 24 8 gr Nine pellets of 00 buckshot 481 2 gr Wadding 6 4 gr Propellant half 191 0 gr Nitro card 13 0 gr Gas seal 17 0 gr Powder 29 0 gr Hull 117 2 gr Primer 14 8 gr for a grand total of 703 4 grains for a fully assembled cartridge There s certainly a bit of tolerance to these measurements but they should serve as a suitable starting point for weights Now to start measuring the hull and nosecone to draw up in CAD 10 comments so far Add Your Comment Reply TheBig1 said 2015 10 23 05 00 Very interesting concept I had never heard of it before although I follow numerous gun related channels on YouTube AR 10s aren t exactly common over here in Germany thanks to our rather restrictive gun laws Looking forward to updates on your reverse engineering process Reply Salty said 2015 11 03 00 05 I ve been tinkering using 50 bmg as the shotshell So mainly all ya needa source is the nose cone I was thinkin a plastic Easter egg for lack of an easier setup I love the concept they just didn t go about it correctly Give away the Ammo etc Reply Have Blue said 2015 11 03 09 05 How much luck have you had with the 50BMG cases I kind of discarded that idea due to the base on the 50 being around 046 smaller in diameter than the base of the RAS 12 Are you fire forming the brass in some manner Reply Salty said 2015 11 09 11 02 Yep fire formed in 12 ga after annealing Then used a lathe to turn down the rim to where the ras bolt will grab it Gettin s bulge about 1 3 up 50bmg but that brass is so thick I m not sure it ll matter Where can we find

    Original URL path: http://haveblue.org/?p=1936&replytocom=1319590 (2016-04-26)
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  • Have Blue [dot org] » Gunsmithing the RAS-12 – Part 1
    15 platform The rounded nose and rebated rim makes feeding far simpler than with a standard 12ga shotshell and allows for easy adaptation of existing magazines The most significant feature of the cartridges is obvious they are not of metal construction but polymer US patent 9109850 calls out polycarbonate and nylon as suitable materials though various online sources specifically note polycarbonate as the hull This feature alone is what made me take notice of the system given that I ve done a bit of tinkering with 3D printed polymers in gunsmithing applications Even if supplies of the original ammunition dry up cough Gyrojet cough Dardick cough EtronX cough it should still be possible to recreate the cartridges in a reverse engineered fashion I m somewhat surprised that the RAS 12 designers didn t opt to open source the design as SAAMI standardization is precisely what has allowed previously proprietary cartridges to survive in the market if not outright flourish I carefully disassembled a cartridge to determine the weights in grains for all of the components Projectile half 512 4 gr Nosecone 24 8 gr Nine pellets of 00 buckshot 481 2 gr Wadding 6 4 gr Propellant half 191 0 gr Nitro card 13 0 gr Gas seal 17 0 gr Powder 29 0 gr Hull 117 2 gr Primer 14 8 gr for a grand total of 703 4 grains for a fully assembled cartridge There s certainly a bit of tolerance to these measurements but they should serve as a suitable starting point for weights Now to start measuring the hull and nosecone to draw up in CAD 10 comments so far Add Your Comment Reply TheBig1 said 2015 10 23 05 00 Very interesting concept I had never heard of it before although I follow numerous gun related channels on YouTube AR 10s aren t exactly common over here in Germany thanks to our rather restrictive gun laws Looking forward to updates on your reverse engineering process Reply Salty said 2015 11 03 00 05 I ve been tinkering using 50 bmg as the shotshell So mainly all ya needa source is the nose cone I was thinkin a plastic Easter egg for lack of an easier setup I love the concept they just didn t go about it correctly Give away the Ammo etc Reply Have Blue said 2015 11 03 09 05 How much luck have you had with the 50BMG cases I kind of discarded that idea due to the base on the 50 being around 046 smaller in diameter than the base of the RAS 12 Are you fire forming the brass in some manner Reply Salty said 2015 11 09 11 02 Yep fire formed in 12 ga after annealing Then used a lathe to turn down the rim to where the ras bolt will grab it Gettin s bulge about 1 3 up 50bmg but that brass is so thick I m not sure it ll matter Where can we find

    Original URL path: http://haveblue.org/?p=1936&replytocom=1325443 (2016-04-26)
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  • Have Blue [dot org] » Gunsmithing the RAS-12 – Part 1
    platform The rounded nose and rebated rim makes feeding far simpler than with a standard 12ga shotshell and allows for easy adaptation of existing magazines The most significant feature of the cartridges is obvious they are not of metal construction but polymer US patent 9109850 calls out polycarbonate and nylon as suitable materials though various online sources specifically note polycarbonate as the hull This feature alone is what made me take notice of the system given that I ve done a bit of tinkering with 3D printed polymers in gunsmithing applications Even if supplies of the original ammunition dry up cough Gyrojet cough Dardick cough EtronX cough it should still be possible to recreate the cartridges in a reverse engineered fashion I m somewhat surprised that the RAS 12 designers didn t opt to open source the design as SAAMI standardization is precisely what has allowed previously proprietary cartridges to survive in the market if not outright flourish I carefully disassembled a cartridge to determine the weights in grains for all of the components Projectile half 512 4 gr Nosecone 24 8 gr Nine pellets of 00 buckshot 481 2 gr Wadding 6 4 gr Propellant half 191 0 gr Nitro card 13 0 gr Gas seal 17 0 gr Powder 29 0 gr Hull 117 2 gr Primer 14 8 gr for a grand total of 703 4 grains for a fully assembled cartridge There s certainly a bit of tolerance to these measurements but they should serve as a suitable starting point for weights Now to start measuring the hull and nosecone to draw up in CAD 10 comments so far Add Your Comment Reply TheBig1 said 2015 10 23 05 00 Very interesting concept I had never heard of it before although I follow numerous gun related channels on YouTube AR 10s aren t exactly common over here in Germany thanks to our rather restrictive gun laws Looking forward to updates on your reverse engineering process Reply Salty said 2015 11 03 00 05 I ve been tinkering using 50 bmg as the shotshell So mainly all ya needa source is the nose cone I was thinkin a plastic Easter egg for lack of an easier setup I love the concept they just didn t go about it correctly Give away the Ammo etc Reply Have Blue said 2015 11 03 09 05 How much luck have you had with the 50BMG cases I kind of discarded that idea due to the base on the 50 being around 046 smaller in diameter than the base of the RAS 12 Are you fire forming the brass in some manner Reply Salty said 2015 11 09 11 02 Yep fire formed in 12 ga after annealing Then used a lathe to turn down the rim to where the ras bolt will grab it Gettin s bulge about 1 3 up 50bmg but that brass is so thick I m not sure it ll matter Where can we find nose

    Original URL path: http://haveblue.org/?p=1936&replytocom=1325607 (2016-04-26)
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