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Posted: 2/14/2016 12:57:10 AM EDT
[#1]
Quote HistoryQuoted: I hope so... I should know how well their "Freedom-15" lowers work pretty soon... I couldn't resist and ended up buying a 10 pour kit with the 8 color pack. Quote HistoryQuoted: Quoted: I'd be curious if the AR15Mold.com people took into account any of the shrinkage from the material. I hope so... I should know how well their "Freedom-15" lowers work pretty soon... I couldn't resist and ended up buying a 10 pour kit with the 8 color pack.  the kit is just a little more than i want to pay to experiment but it looks like a fun project  |
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Posted: 2/14/2016 11:34:44 AM EDT
[#2]
Could you finish one of these and use it to make the mold?
http://aresarmor.com/store/Item/Polymer-80-Black |
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Posted: 2/14/2016 11:58:53 AM EDT
[#3]
Really neat.
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Posted: 2/14/2016 2:14:29 PM EDT
[#4]
Quote HistoryQuoted: Could you finish one of these and use it to make the mold?
http://aresarmor.com/store/Item/Polymer-80-Black Yes. |
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Posted: 2/14/2016 4:35:46 PM EDT
[#5]
Quote HistoryQuoted:
please take lots of pics and notes and post a copy of the MSDS
the kit is just a little more than i want to pay to experiment but it looks like a fun project
Quote HistoryQuoted:
Quoted:
Quoted:
I'd be curious if the AR15Mold.com people took into account any of the shrinkage from the material. I hope so... I should know how well their "Freedom-15" lowers work pretty soon... I couldn't resist and ended up buying a 10 pour kit with the 8 color pack.
the kit is just a little more than i want to pay to experiment but it looks like a fun project
They believe it's Task 21 from this thread. Which is not compatible with silicone molds. |
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Posted: 2/14/2016 9:55:03 PM EDT
[#6]
Quote HistoryQuote HistoryQuoted: Quoted: Quoted: Quoted: I'd be curious if the AR15Mold.com people took into account any of the shrinkage from the material. I hope so... I should know how well their "Freedom-15" lowers work pretty soon... I couldn't resist and ended up buying a 10 pour kit with the 8 color pack. the kit is just a little more than i want to pay to experiment but it looks like a fun project They believe it's Task 21 from this thread. Which is not compatible with silicone molds. By they, you mean me  . It is compatible with a silicone mold, but just not the type we've been using. Hence why we never even considered it. After looking over the AR15molds website, videos, and pictures I'm starting to think that using a silicone product for the mold might not be the best way to go. It might be better to make a rigid mold and use metal insert pieces (which will allow you to cast a perfect detent channel) like they do. This means a lot more work in making the mold, but the end result might make it worth while. |
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Posted: 2/14/2016 11:20:06 PM EDT
[#7]
Quote HistoryQuoted:
By they, you mean me . It is compatible with a silicone mold, but just not the type we've been using. Hence why we never even considered it. After looking over the AR15molds website, videos, and pictures I'm starting to think that using a silicone product for the mold might not be the best way to go. It might be better to make a rigid mold and use metal insert pieces (which will allow you to cast a perfect detent channel) like they do. This means a lot more work in making the mold, but the end result might make it worth while.
No one disagreed
I agree that it's the better way, that's the way the pros do it. What's another material that could be used, like a concrete/plaster/clay/whatever. |
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Posted: 2/14/2016 11:45:19 PM EDT
[#8]
Quote HistoryQuoted: No one disagreed I agree that it's the better way, that's the way the pros do it. What's another material that could be used, like a concrete/plaster/clay/whatever. Quote HistoryQuoted: Quoted: By they, you mean me . It is compatible with a silicone mold, but just not the type we've been using. Hence why we never even considered it. After looking over the AR15molds website, videos, and pictures I'm starting to think that using a silicone product for the mold might not be the best way to go. It might be better to make a rigid mold and use metal insert pieces (which will allow you to cast a perfect detent channel) like they do. This means a lot more work in making the mold, but the end result might make it worth while. No one disagreed I agree that it's the better way, that's the way the pros do it. What's another material that could be used, like a concrete/plaster/clay/whatever. Pretty much any of the stuff we're already using to cast lowers with. |
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Posted: 2/15/2016 1:26:36 AM EDT
[#9]
Quote HistoryQuoted: By they, you mean me . It is compatible with a silicone mold, but just not the type we've been using. Hence why we never even considered it. After looking over the AR15molds website, videos, and pictures I'm starting to think that using a silicone product for the mold might not be the best way to go. It might be better to make a rigid mold and use metal insert pieces (which will allow you to cast a perfect detent channel) like they do. This means a lot more work in making the mold, but the end result might make it worth while. Hmm, where could we get metal insert pieces w/ perfectly drilled FCS holes for a reasonable price... http://www.theflatspot.net/ar-15-receiver-flat.html |
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Posted: 2/15/2016 1:41:53 AM EDT
[#10]
I was talking about using pins through the mold but yeah that would work too I suppose.
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Posted: 2/15/2016 8:39:19 AM EDT
[#11]
Quote HistoryQuoted:
I was talking about using pins through the mold but yeah that would work too I suppose. That ar15mold.com place sells "replacement" parts for their mold kits. http://ar15mold.com/spare-freedom-15-small-parts-kit/ However, I would bet a trip to your local hardware store, with a pair of calipers to measure the thickness of some steel or brass rods and wire would yield much cheaper results. Use the pins in your lower to cast the mold, and then you already have the holes set into your mold to align them when you cast the new lowers. |
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Posted: 2/15/2016 8:08:13 PM EDT
[#12]
i wondor if you could make a magazine like this... for instance if you lived in a regulated state how would the law apply?
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Posted: 2/15/2016 8:33:47 PM EDT
[#13]
Quote HistoryQuoted:
i wondor if you could make a magazine like this... for instance if you lived in a regulated state how would the law apply? Most ban states ban the manufacture of high cap mags, so it would be illegal. Of course, if you don't tell anyone, who's going to know. |
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Posted: 2/15/2016 8:41:31 PM EDT
[#14]
Quote HistoryQuoted:
i wondor if you could make a magazine like this... for instance if you lived in a regulated state how would the law apply? Let me preface this by saying I am not a lawyer. However, it would depend on the details of the regulations of that State in question. Do they regulate the sale? Transfer? Manufacture? Or more likely completely prohibit the possession of the restricted magazines by anyone other than the government? Most of them that have instituted a magazine capacity limit, regulate the possession of them. So regardless if you bought it, smuggled it, "found" it while digging in your back yard, or made it in your garage like these methods, you're toast just for having it. One example of this would be the NYSAFE Act. It removed all grandfathering provisions and any other exception to the 10 round capacity limit. Plain and simple, if you live in NY State and have a high capacity magazine, you're toast. In California, if you don't assemble this lower with a "bullet button" magazine catch, then you're toast under CA law. In NY, if you put on just one single one of the "evil" assault weapon features (most AWBs require multiple "evil" components, but NYSAFE Act reduced it to just one), you're toast under NY law. If you make this receiver into a SBR without sending $200 and a Form 1 to ATF (and adequately marking the receiver according to ATF requirements), you're toast under federal law. The only thing making your own receiver avoids is the transaction paperwork process and record-keeping with a licensed gun dealer. There is no such process for magazines or any of the components we are adding to this receiver. If you are prohibited from owning firearms under local or federal law, because of being a convicted felon, addict, wife-beater, live in a gun free zone, etc. You are still breaking the law if you make one. Now, all this talk of toast has me hungry. I'm going to eat! |
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Posted: 2/15/2016 8:46:48 PM EDT
[#15]
Quote HistoryQuoted: Let me preface this by saying I am not a lawyer. However, it would depend on the details of the regulations of that State in question. Do they regulate the sale? Transfer? Manufacture? Or more likely completely prohibit the possession of the restricted magazines by anyone other than the government? Most of them that have instituted a magazine capacity limit, regulate the possession of them. So regardless if you bought it, smuggled it, "found" it while digging in your back yard, or made it in your garage like these methods, you're toast just for having it. One example of this would be the NYSAFE Act. It removed all grandfathering provisions and any other exception to the 10 round capacity limit. Plain and simple, if you live in NY State and have a high capacity magazine, you're toast. In California, if you don't assemble this lower with a "bullet button" magazine catch, then you're toast under CA law. In NY, if you put on just one single one of the "evil" assault weapon features (most AWBs require multiple "evil" components, but NYSAFE Act reduced it to just one), you're toast under NY law. If you make this receiver into a SBR without sending $200 and a Form 1 to ATF (and adequately marking the receiver according to ATF requirements), you're toast under federal law. The only thing making your own receiver avoids is the transaction paperwork process and record-keeping with a licensed gun dealer. There is no such process for magazines or any of the components we are adding to this receiver. If you are prohibited from owning firearms under local or federal law, because of being a convicted felon, addict, wife-beater, live in a gun free zone, etc. You are still breaking the law if you make one. Now, all this talk of toast has me hungry. I'm going to eat! Quote HistoryQuoted: Quoted: i wondor if you could make a magazine like this... for instance if you lived in a regulated state how would the law apply? Let me preface this by saying I am not a lawyer. However, it would depend on the details of the regulations of that State in question. Do they regulate the sale? Transfer? Manufacture? Or more likely completely prohibit the possession of the restricted magazines by anyone other than the government? Most of them that have instituted a magazine capacity limit, regulate the possession of them. So regardless if you bought it, smuggled it, "found" it while digging in your back yard, or made it in your garage like these methods, you're toast just for having it. One example of this would be the NYSAFE Act. It removed all grandfathering provisions and any other exception to the 10 round capacity limit. Plain and simple, if you live in NY State and have a high capacity magazine, you're toast. In California, if you don't assemble this lower with a "bullet button" magazine catch, then you're toast under CA law. In NY, if you put on just one single one of the "evil" assault weapon features (most AWBs require multiple "evil" components, but NYSAFE Act reduced it to just one), you're toast under NY law. If you make this receiver into a SBR without sending $200 and a Form 1 to ATF (and adequately marking the receiver according to ATF requirements), you're toast under federal law. The only thing making your own receiver avoids is the transaction paperwork process and record-keeping with a licensed gun dealer. There is no such process for magazines or any of the components we are adding to this receiver. If you are prohibited from owning firearms under local or federal law, because of being a convicted felon, addict, wife-beater, live in a gun free zone, etc. You are still breaking the law if you make one. Now, all this talk of toast has me hungry. I'm going to eat! Yup completely depends on the state. |
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Posted: 2/16/2016 11:10:17 AM EDT
[#16]
Quote HistoryQuoted:
i wondor if you could make a magazine like this... for instance if you lived in a regulated state how would the law apply? yes, I've made copies of special mags for AK type rock-in, that were originally made with plastic injection molds and steel inserts. I've no idea how they would fare, those rifles haven't been built yet, but it's doable and is a subject to the same laws, if you are in ban state, making a post-ban over 10 cap mag is a crime. However, the making setup is portable enough that you can make in a free state. |
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Posted: 2/16/2016 11:14:53 AM EDT
[#17]
Quote HistoryQuoted:
Hmm, where could we get metal insert pieces w/ perfectly drilled FCS holes for a reasonable price... http://www.theflatspot.net/ar-15-receiver-flat.html Quote HistoryQuoted:
Quoted: By they, you mean me . It is compatible with a silicone mold, but just not the type we've been using. Hence why we never even considered it. After looking over the AR15molds website, videos, and pictures I'm starting to think that using a silicone product for the mold might not be the best way to go. It might be better to make a rigid mold and use metal insert pieces (which will allow you to cast a perfect detent channel) like they do. This means a lot more work in making the mold, but the end result might make it worth while. Hmm, where could we get metal insert pieces w/ perfectly drilled FCS holes for a reasonable price... http://www.theflatspot.net/ar-15-receiver-flat.html This is from a really old times, you can find PDF version of this guy making AR lower from separate parts that bolt together. I like the buffer and grip parts come together, from an aluminum. The rest can be plastic. 
The idea is that buffer/ grip part is not a firearm and is the worst abused parts. If those can be gotten cheap, there could be some possibilities. 
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Posted: 2/16/2016 1:06:37 PM EDT
[#18]
Quote HistoryQuoted:
This is from a really old times, you can find PDF version of this guy making AR lower from separate parts that bolt together. I like the buffer and grip parts come together, from an aluminum. The rest can be plastic. http://i80.photobucket.com/albums/j184/mag-lock/AR15MOD2.jpg The idea is that buffer/ grip part is not a firearm and is the worst abused parts. If those can be gotten cheap, there could be some possibilities. I have the PDF files from his Version 2 build. Not sure what all the changes are as I don't have the V1, but I know at the very least the mag well side plates changed. I can provide them if anyone wants. |
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Posted: 2/16/2016 1:44:07 PM EDT
[#19]
The bolt-together from machined aluminum flats is a great idea, but I believe it stems from the era before forged 80% lowers were widely available. If you have the tooling to make the machined aluminum flats, you can much more easily mill an inexpensive 80% lower.
The last folks making a "bolt-together" 80% lower was KT Ordnance: 
They now only accept wholesale orders or group buys, not individual purchases. |
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Posted: 2/16/2016 3:33:52 PM EDT
[#20]
Quote HistoryQuoted:
The bolt-together from machined aluminum flats is a great idea, but I believe it stems from the era before forged 80% lowers were widely available. If you have the tooling to make the machined aluminum flats, you can much more easily mill an inexpensive 80% lower. The starting material is much different though. You don't need an 80% lower as you could start from 1/8" and 1/4" plate and some small blocks. Not as easy to machine as an 80% I'd assume, and to some point you could argue you could just hog out a lower from one large billet. Either way though, the bolt-together has a certain visual charm. I can image that thing, or the weld together, looking awesome with an aged/worn finish. Now if only you could do a matching upper... Rough and blocky looking. Man don't give me bad ideas of things to make in CAD.
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Posted: 2/16/2016 6:55:53 PM EDT
[#21]
Quote HistoryQuoted:
The bolt-together from machined aluminum flats is a great idea, but I believe it stems from the era before forged 80% lowers were widely available. If you have the tooling to make the machined aluminum flats, you can much more easily mill an inexpensive 80% lower. The last folks making a "bolt-together" 80% lower was KT Ordnance: http://www.ktordnance.com/detail/kt15bx.jpg They now only accept wholesale orders or group buys, not individual purchases. My sentiment exactly, the only difference here is that no milling is needed if purchasing this kit, just drilling. Most AR mill jigs aren't full proof and cost money, same as mills. Drill press is pretty common so having an 80% lower that needs only a drill press would be an advantage, I am not sure how much market vise. On the bolt-on lower (my point of attraction) the only part that needs to be made from reinforced plastic or aluminum is that handle/buffer ring. Other parts aren't that hard to make or expensive. The flats can be laser cut and stamped. The magwell two pieces, probably best to make them from injection plastic, they are royal pain to machine. |
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Posted: 2/16/2016 7:09:37 PM EDT
[#22]
Quote HistoryQuoted: My sentiment exactly, the only difference here is that no milling is needed if purchasing this kit, just drilling. Most AR mill jigs aren't full proof and cost money, same as mills. Drill press is pretty common so having an 80% lower that needs only a drill press would be an advantage, I am not sure how much market vise.
On the bolt-on lower (my point of attraction) the only part that needs to be made from reinforced plastic or aluminum is that handle/buffer ring. Other parts aren't that hard to make or expensive. The flats can be laser cut and stamped. The magwell two pieces, probably best to make them from injection plastic, they are royal pain to machine. Given we now have a universal steel jig that allows one to use $100 wood routers to mill billet or forged 80% lowers, I think we have an explanation as to why KTO stopped production of their bolt together 80%. The only three viable alternatives to the aluminum 80% lower @ the moment are the weldable steel flats, 3-D printing, or Fruity Ghost/commercial equivalent. Wood is an attractive alternative, but if you can do a wood, you can do a 0% from aluminum cans, and the Lego lower is on hold pending promising results from Fruity Ghost. |
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Posted: 2/18/2016 1:37:00 PM EDT
[#23]
Quote HistoryQuoted:
On the bolt-on lower (my point of attraction) the only part that needs to be made from reinforced plastic or aluminum is that handle/buffer ring. Other parts aren't that hard to make or expensive. The flats can be laser cut and stamped. The magwell two pieces, probably best to make them from injection plastic, they are royal pain to machine. Quote HistoryQuoted:
On the bolt-on lower (my point of attraction) the only part that needs to be made from reinforced plastic or aluminum is that handle/buffer ring. Other parts aren't that hard to make or expensive. The flats can be laser cut and stamped. The magwell two pieces, probably best to make them from injection plastic, they are royal pain to machine. So basically you could do the rear buffer area out of aluminum, mill everything else from plastic sheet, and presto. Or mold the rest. Quoted:
The only three viable alternatives to the aluminum 80% lower @ the moment are the weldable steel flats, 3-D printing, or Fruity Ghost/commercial equivalent. Wood is an attractive alternative, but if you can do a wood, you can do a 0% from aluminum cans, and the Lego lower is on hold pending promising results from Fruity Ghost. Someone did an all-wood lower. They had issues at the buffer tube / receiver extension threads. That said, you could reinforce that and have an otherwise all-wood lower. I'd have to find the links of the guy who did it, but he tried it with pine and then something more durable. |
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Posted: 2/18/2016 3:22:09 PM EDT
[#24]
Quote HistoryQuoted:
Someone did an all-wood lower. They had issues at the buffer tube / receiver extension threads. That said, you could reinforce that and have an otherwise all-wood lower. I'd have to find the links of the guy who did it, but he tried it with pine and then something more durable. Quote HistoryQuoted: Quoted:
The only three viable alternatives to the aluminum 80% lower @ the moment are the weldable steel flats, 3-D printing, or Fruity Ghost/commercial equivalent. Wood is an attractive alternative, but if you can do a wood, you can do a 0% from aluminum cans, and the Lego lower is on hold pending promising results from Fruity Ghost. Someone did an all-wood lower. They had issues at the buffer tube / receiver extension threads. That said, you could reinforce that and have an otherwise all-wood lower. I'd have to find the links of the guy who did it, but he tried it with pine and then something more durable. http://www.weaponeer.net/forum/forum_posts.asp?TID=8035 Orion's Hammer used pine, and then welded plastic cutting boards for two 0% lower builds. The ultimate failure in his Pine ABORTION (His acronym) was the breakage of the front takedown pin lugs, which allowed the upper to pivot, and jam after the 3rd shot. |
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Posted: 2/18/2016 4:38:29 PM EDT
[#25]
Quote HistoryQuoted:
Orion's Hammer used pine, and then welded plastic cutting boards for two 0% lower builds. The ultimate failure in his Pine ABORTION (His acronym) was the breakage of the front takedown pin lugs, which allowed the upper to pivot, and jam after the 3rd shot. That's the one! I swore it was a failure at the rear but looking back at the thread I see I was wrong. I also see you're a member there. Lol. |
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Posted: 2/18/2016 6:20:28 PM EDT
[#26]
Curiosity: How would a urethane rubber, such as PMC-744 work for creating the mold as opposed to silicone? Would it be more durable than the silicone? More friendly towards resins that don't like the silicone? Is it not flexible enough to peel away from the casting as easily as the silicone?
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Posted: 2/18/2016 8:03:51 PM EDT
[#27]
Quote HistoryQuoted:
Curiosity: How would a urethane rubber, such as PMC-744 work for creating the mold as opposed to silicone? Would it be more durable than the silicone? More friendly towards resins that don't like the silicone? Is it not flexible enough to peel away from the casting as easily as the silicone? There are different urethanes. The biggest issue is that urethanes tend to be thicker and need to be degassed before pouring. Moldstar doesn't need to be degassed most of the time. I'm not 100% on that, but I certainly haven't done it. I don't remember exactly, there are specs on smoothon site for urethanes and silicones. You want to check tear resistance (elongation at break), pouring viscosity. |
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Posted: 2/22/2016 9:10:14 AM EDT
[#28]
Quote HistoryQuoted:
There are different urethanes. The biggest issue is that urethanes tend to be thicker and need to be degassed before pouring. Moldstar doesn't need to be degassed most of the time. I'm not 100% on that, but I certainly haven't done it. I don't remember exactly, there are specs on smoothon site for urethanes and silicones. You want to check tear resistance (elongation at break), pouring viscosity. Quote HistoryQuoted:
Quoted:
Curiosity: How would a urethane rubber, such as PMC-744 work for creating the mold as opposed to silicone? Would it be more durable than the silicone? More friendly towards resins that don't like the silicone? Is it not flexible enough to peel away from the casting as easily as the silicone? There are different urethanes. The biggest issue is that urethanes tend to be thicker and need to be degassed before pouring. Moldstar doesn't need to be degassed most of the time. I'm not 100% on that, but I certainly haven't done it. I don't remember exactly, there are specs on smoothon site for urethanes and silicones. You want to check tear resistance (elongation at break), pouring viscosity. According to Smooth-On's online information, most of the Urethane rubbers have much lower cps ratings compared with Moldstar Silicone rubber. Specifically, PMC 744 compared to Moldstar 30 (assuming based on the first post where you recommended a hardness between 30-40), the urethane rubber actually has a considerably higher Shore A hardness rating (44>30), with slightly better tear strength ratings(Elongation 400% vs 339% and 90pli vs. 88pli). The viscosity difference is huge, with only 3400 for the PMC744 compared to 12,500cps for the MoldStar. The downsides to PMC744 look to be a shorter pot life (15minutes vs. 45minutes) and longer time required in the mold (16 hours vs. 6 hours), either of which are plenty feasible for creating a mold, I think. Am I missing something? |
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Posted: 2/22/2016 10:45:51 PM EDT
[#29]
Quote HistoryQuoted:
Correct me if I'm wrong, but a lower cps means less viscosity, right? I might be ignorant, but wouldn't a lower viscosity generally mean air bubbles float out, easier? According to Smooth-On's online information, most of the Urethane rubbers have much lower cps ratings compared with Moldstar Silicone rubber. Specifically, PMC 744 compared to Moldstar 30 (assuming based on the first post where you recommended a hardness between 30-40), the urethane rubber actually has a considerably higher Shore A hardness rating (44>30), with slightly better tear strength ratings(Elongation 400% vs 339% and 90pli vs. 88pli). The viscosity difference is huge, with only 3400 for the PMC744 compared to 12,500cps for the MoldStar. The downsides to PMC744 look to be a shorter pot life (15minutes vs. 45minutes) and longer time required in the mold (16 hours vs. 6 hours), either of which are plenty feasible for creating a mold, I think. Am I missing something? Quote HistoryQuoted:
Quoted:
Quoted:
Curiosity: How would a urethane rubber, such as PMC-744 work for creating the mold as opposed to silicone? Would it be more durable than the silicone? More friendly towards resins that don't like the silicone? Is it not flexible enough to peel away from the casting as easily as the silicone? There are different urethanes. The biggest issue is that urethanes tend to be thicker and need to be degassed before pouring. Moldstar doesn't need to be degassed most of the time. I'm not 100% on that, but I certainly haven't done it. I don't remember exactly, there are specs on smoothon site for urethanes and silicones. You want to check tear resistance (elongation at break), pouring viscosity. According to Smooth-On's online information, most of the Urethane rubbers have much lower cps ratings compared with Moldstar Silicone rubber. Specifically, PMC 744 compared to Moldstar 30 (assuming based on the first post where you recommended a hardness between 30-40), the urethane rubber actually has a considerably higher Shore A hardness rating (44>30), with slightly better tear strength ratings(Elongation 400% vs 339% and 90pli vs. 88pli). The viscosity difference is huge, with only 3400 for the PMC744 compared to 12,500cps for the MoldStar. The downsides to PMC744 look to be a shorter pot life (15minutes vs. 45minutes) and longer time required in the mold (16 hours vs. 6 hours), either of which are plenty feasible for creating a mold, I think. Am I missing something? I don't think that you are missing anything here. 1. One issue I see is the short pot life. 15min vs 45 is a big difference and it starts as soon as you start mixing ingredients, by the time you pour, you have a little time to get bubbles out, then it starts to thicken which depends on temperature etc. 2 Price wise, trial size is about the same. Gallon/30# slightly cheaper for PMC744. Keep in mind though, urethanes are moisture sensitive and in my personal experience doing it in a basement, an old can of urethane has gone non-gelling on me before, i.e. the mix just didn't seem to gel together or partially, probably due to moisture. 3. I looked at another option once, the Moldstar is a platinum cured silicone rubber. The tin cured rubber is cheaper, I believe, but needs to be degassed. That may be another option. 4. Most castable plastics are actually urethanes, like Smoothcast 300 or others. Urethanes would stick to urethanes, so you need a release agent. With silicones, it's not really needed, but a good idea to use once in a while. |
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Posted: 3/30/2016 7:21:08 PM EDT
[#30]
How about "Cold metal casting"?
basically adding metal powder to the casting material 
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Posted: 3/30/2016 10:01:03 PM EDT
[#31]
Well, the metal will certainly add volume, which might reduce cost. Unfortunately, it won't add strength. However, it would certainly satisfy the Federal law regarding detection of plastic firearms - but the bbl, bolt, bolt carrier, buffer, etc of the rest of the AR will satisfy that requirement.
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Posted: 3/31/2016 10:58:24 AM EDT
[#32]
Quote HistoryQuoted:
How about "Cold metal casting"? basically adding metal powder to the casting material He's got a nice desktop SLA unit for that print. Sure makes using AM for patterns much easier when it comes to small parts. Thermoplastic extrusion would be a nightmare to sand to that level and you'd lose so many of those fine details. As for metal particles in the cast, I've got some samples of metal filled nylon at my desk and I feel it is mostly for looks. I don't see it adding any real benefit strength wise, as BackBurner mentioned already. |
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Posted: 3/31/2016 11:19:41 AM EDT
[#33]
If the metal flakes were super porous and had tons of "grab" it could help, but might as well go with shredded fiberglass bits at that point.
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Posted: 5/8/2016 2:35:21 PM EDT
[#34]
I have found my summer project...
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Posted: 6/20/2016 10:57:51 PM EDT
[#35]
I've been mulling over this idea for a couple of years myself but never had the guts to try it out. I commend all those who took on this project to see what comes of it. After my own back and forth, Im finally going to dive in and take stab it. I was interested however in seeing if you, Boris have anymore of those rear take down reinforcements available? If you could please let me know I'd appreciate it.
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Posted: 6/23/2016 12:02:35 AM EDT
[#36]
Quote HistoryQuoted:
http://www.gwacsarmory.com/limited-lifetime-warranty/ Reads like MK1's aren't covered under that lifetime warranty....which their "lifetime warranty" reads like a joke to me. It's reads more like a "lifetime replacement" warranty so long as we deem it to be a manufacturing defect (normal wear and tear not covered, as per usual with these things...so good luck there). Quote HistoryQuoted:
Quoted:
No, I'm aware of that. But my understanding is that GWACs also took on warranty responsibility for the Mk. I's. If that's the case thy might have knowledge of how to deal with their dismantlement, unless their warranty replacement plan is "Fucking fucker's fucking fucked - her's your Mark II replacement." http://www.gwacsarmory.com/limited-lifetime-warranty/ Reads like MK1's aren't covered under that lifetime warranty....which their "lifetime warranty" reads like a joke to me. It's reads more like a "lifetime replacement" warranty so long as we deem it to be a manufacturing defect (normal wear and tear not covered, as per usual with these things...so good luck there). Basically the same warranty as all the major US tool manufacturers nowadays. |
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Posted: 6/26/2016 6:40:00 PM EDT
[#37]
Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze.
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Posted: 6/26/2016 7:05:46 PM EDT
[#38]
Quote HistoryQuoted:
Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze. You could do that, but you'd be better off using a 3D printer to make the positive, because you're going to need to scale it up about 3-4% to account for the shrinkage that happens when you cast aluminum. 1-2% for bronze. With the urethane, you can just make a silicone mold off of any AR lower you have that's handy, and it casts at a 1:1 ratio. |
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Posted: 6/26/2016 9:05:43 PM EDT
[#39]
Quote HistoryQuoted:
Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze. Bronze lower 
If you want to get things persactly, cast an 80% lower out of aluminum cans, and then mill it. |
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Posted: 6/26/2016 9:53:18 PM EDT
[#40]
Quote HistoryQuoted: You could do that, but you'd be better off using a 3D printer to make the positive, because you're going to need to scale it up about 3-4% to account for the shrinkage that happens when you cast aluminum. 1-2% for bronze. With the urethane, you can just make a silicone mold off of any AR lower you have that's handy, and it casts at a 1:1 ratio. Quote HistoryQuoted: Quoted: Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze. You could do that, but you'd be better off using a 3D printer to make the positive, because you're going to need to scale it up about 3-4% to account for the shrinkage that happens when you cast aluminum. 1-2% for bronze. With the urethane, you can just make a silicone mold off of any AR lower you have that's handy, and it casts at a 1:1 ratio. Right. What I'm getting at is - is that 1-2% going to be significant enough to matter. We're talking about a lower - something with very few moving parts, and arguably the most precise things will be the magwell - which could be filed and sanded, and the buffer tube extension ring - which could be bulked up in our "mold" and threaded with a large size die and a drill press. Are there any metals that don't shrink significantly? A 3D Printed Wax Positive blank to be cast would be cool as fuck - for the record - and would yield a much better output than....well...pretty much anything plastic |
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Posted: 6/26/2016 10:25:45 PM EDT
[#41]
It would be interesting to try just for the hell of it or as a conversation piece. However, seeing as people have problems mating various manufacturers factory made uppers and lowers, I'd say that the front and rear takedown pin tolerances are pretty tight. Filing your lower a bit wider at the front pin boss wouldn't be hard, but getting the holes to line up would be harder.
At a minimum, I'd NOT drill the FCG holes or put them as parts of the casting. And drill them after the fact. If you try and make those parts of the casting, you'll just get egged out holes that suck and an unreliable FCG. Although KNS anti-rotation pins might stay put. The beauty of a polymer cast lower is that once you've got a silicone mold you're happy with, and if you buy your 2-part polyurethane by the gallon, each new lower would cost you about a dollar. So who cares if it breaks or wears out? |
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Posted: 6/26/2016 10:36:55 PM EDT
[#42]
Quote HistoryQuoted: It would be interesting to try just for the hell of it or as a conversation piece. However, seeing as people have problems mating various manufacturers factory made uppers and lowers, I'd say that the front and rear takedown pin tolerances are pretty tight. Filing your lower a bit wider at the front pin boss wouldn't be hard, but getting the holes to line up would be harder.
At a minimum, I'd NOT drill the FCG holes or put them as parts of the casting. And drill them after the fact. If you try and make those parts of the casting, you'll just get egged out holes that suck and an unreliable FCG. Although KNS anti-rotation pins might stay put. The beauty of a polymer cast lower is that once you've got a silicone mold you're happy with, and if you buy your 2-part polyurethane by the gallon, each new lower would cost you about a dollar. So who cares if it breaks or wears out? Could one build up a steel mold using parts from the Flat Spot, and use steel pins or screws for the FCS holes & takedown pins? Once the mold cools, unscrew them or punch them out? |
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Posted: 6/26/2016 10:52:23 PM EDT
[#43]
Quote HistoryQuoted: It would be interesting to try just for the hell of it or as a conversation piece. However, seeing as people have problems mating various manufacturers factory made uppers and lowers, I'd say that the front and rear takedown pin tolerances are pretty tight. Filing your lower a bit wider at the front pin boss wouldn't be hard, but getting the holes to line up would be harder. At a minimum, I'd NOT drill the FCG holes or put them as parts of the casting. And drill them after the fact. If you try and make those parts of the casting, you'll just get egged out holes that suck and an unreliable FCG. Although KNS anti-rotation pins might stay put. The beauty of a polymer cast lower is that once you've got a silicone mold you're happy with, and if you buy your 2-part polyurethane by the gallon, each new lower would cost you about a dollar. So who cares if it breaks or wears out? The plastic is awesome and cool- but my first thought was - "well shit this could go way more long term". |
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Posted: 6/27/2016 1:18:35 PM EDT
[#44]
Another thing to consider - plug the rear takedown hole and drill it manually after everything cools. Your front serves as an index anyway. Then - even if your total mold was 1% smaller, it wouldn't matter. A little filing to fit,
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Posted: 6/28/2016 10:59:30 AM EDT
[#45]
Quote HistoryQuoted:
Right. What I'm getting at is - is that 1-2% going to be significant enough to matter. We're talking about a lower - something with very few moving parts, and arguably the most precise things will be the magwell - which could be filed and sanded, and the buffer tube extension ring - which could be bulked up in our "mold" and threaded with a large size die and a drill press. Are there any metals that don't shrink significantly? A 3D Printed Wax Positive blank to be cast would be cool as fuck - for the record - and would yield a much better output than....well...pretty much anything plastic Quote HistoryQuoted:
Quoted:
Quoted:
Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze. You could do that, but you'd be better off using a 3D printer to make the positive, because you're going to need to scale it up about 3-4% to account for the shrinkage that happens when you cast aluminum. 1-2% for bronze. With the urethane, you can just make a silicone mold off of any AR lower you have that's handy, and it casts at a 1:1 ratio. Right. What I'm getting at is - is that 1-2% going to be significant enough to matter. We're talking about a lower - something with very few moving parts, and arguably the most precise things will be the magwell - which could be filed and sanded, and the buffer tube extension ring - which could be bulked up in our "mold" and threaded with a large size die and a drill press. Are there any metals that don't shrink significantly? A 3D Printed Wax Positive blank to be cast would be cool as fuck - for the record - and would yield a much better output than....well...pretty much anything plastic I've been advocating that approach for a while. You can do a LOT of experimentation and prototyping that way, and it's very economical on raw material. Print the core, cast it, measure the casting, adjust the dimensions in the solids model, print, remelt the previous part, cast. Just reuse the same metal over and over until you get it right. |
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Posted: 6/28/2016 4:19:40 PM EDT
[#46]
Quote HistoryQuoted:
I've been advocating that approach for a while. You can do a LOT of experimentation and prototyping that way, and it's very economical on raw material. Print the core, cast it, measure the casting, adjust the dimensions in the solids model, print, remelt the previous part, cast. Just reuse the same metal over and over until you get it right. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Since we are just casting, what's the trade off to make one out of something like discarded pop cans using an improvised forge. Cast the urethane, instead of plastic, do wax, then do a sand cast of something like aluminum or bronze. You could do that, but you'd be better off using a 3D printer to make the positive, because you're going to need to scale it up about 3-4% to account for the shrinkage that happens when you cast aluminum. 1-2% for bronze. With the urethane, you can just make a silicone mold off of any AR lower you have that's handy, and it casts at a 1:1 ratio. Right. What I'm getting at is - is that 1-2% going to be significant enough to matter. We're talking about a lower - something with very few moving parts, and arguably the most precise things will be the magwell - which could be filed and sanded, and the buffer tube extension ring - which could be bulked up in our "mold" and threaded with a large size die and a drill press. Are there any metals that don't shrink significantly? A 3D Printed Wax Positive blank to be cast would be cool as fuck - for the record - and would yield a much better output than....well...pretty much anything plastic I've been advocating that approach for a while. You can do a LOT of experimentation and prototyping that way, and it's very economical on raw material. Print the core, cast it, measure the casting, adjust the dimensions in the solids model, print, remelt the previous part, cast. Just reuse the same metal over and over until you get it right. Oooooh....hadn't thought of that. |
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Posted: 6/28/2016 4:41:24 PM EDT
[#47]
Wow. I wonder how hard it would be to go a few steps further with an aluminum casting using a lost foam method.......
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Posted: 6/28/2016 4:51:25 PM EDT
[#48]
Quote HistoryQuoted:
Wow. I wonder how hard it would be to go a few steps further with an aluminum casting using a lost foam method....... Lost foam and other casting methods are best for high production *after* you get the core dimensions right. Using it for prototyping would involve a lot of hand labor I would think. The idea is that the 3d printer can take the necessity of having a highly skilled pattern maker in the process. |
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Posted: 6/28/2016 5:30:47 PM EDT
[#49]
Noted. Thanks!
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Posted: 6/29/2016 10:42:07 AM EDT
[#50]
If a user with a history of reviewing products for the community here on AR-15.com wants to review our latest and greatest GunMold.com kit which produces our unregistered AR-15 style lower receiver we like to call the Phantom 15 "Ghost Gun" please hit us up via email. We would love to see someone successfully use our Phantom 15 kit to create a metal based AR-15 lower receiver. Can't wait to see someone successfully tackle this bad-add project!
-Mike [email protected] |
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