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I don't know which category to post this comment under, but I chose the AR-15 category even though some answers that folks may have will probably also apply to P80s.
In the old MGB forum there was a topic about JB Weld and fixing Polymer screw ups. If I recall, it was either from @bapegg , or @Hawkeye , but I could be wrong.
I finally "plunged" into the 5D tactical router this weekend for the first time. Up to bat first was a Polymer 80 Rhino AR-15 frame which I got specifically as a test model before trying AR-15 aluminum lowers. Everything went well except a couple of minor marks where I probably should have cleaned out the shavings more often. So, anybody who views this thread, know that the 5D jig works on Polymer 80 frames quite nicely. I throttled the Makita router down to its lowest setting and it machined the plastic quite well with no melting or hot spot marks.
However, there was a somewhat significant issue in the final steps when drilling the larger safety hole, due to it being Polymer and the aggressiveness of the 5D supplied drill bit. I already felt a little uncomfortable drilling this larger hole into plastic with larger bits. And I wasn't let down with my concern. When drilling the hole on the right side of the frame where the safety detent is located, the plastic is very thin inside. When the rotating drill bit cleared into the milled trigger pocket, it blew out some of the plastic tube area where the safety detent resides. The top half area of the detent chamber is blown out with the lower half still intact. The safety still functions and the detent doesn't fall out, but I want to repair the top portion with JB Weld so the bottom half doesn't stress crack and break off over time.
In hindsight, I probably should have drilled the side holes first and was considering doing it, but went with their instructions instead of my instinct. But, their instructions were on a aluminum frame, not plastic. I still question whether drilling the holes in the side as the last step in an aluminum frame is wise. The only reason I could see not drilling the holes first is that the router bit may hang or grab on a burr or portion of the pre-drilled hole as it passes by milling the inside pocket.
So, I have two questions:
1. What type of JB Weld would you purchase? (I will mix in some of the frames plastic shavings from the milling process.)
2. Is there anything that JB Weld WILL NOT stick to? (I would like to stick a dowel or something non-stick into the detent cavity before building the JB weld puddle and shaping it around the dowel.)
I have little experience with the various mixes of JB Weld, other than using the old school Black and Gray stuff in two separate tubes which you mix on a piece of cardboard. There are several epoxy versions it appears that are specifically for plastics or polymers, but I have no clue which is best.
Thanks for any input you can offer.
In the old MGB forum there was a topic about JB Weld and fixing Polymer screw ups. If I recall, it was either from @bapegg , or @Hawkeye , but I could be wrong.
I finally "plunged" into the 5D tactical router this weekend for the first time. Up to bat first was a Polymer 80 Rhino AR-15 frame which I got specifically as a test model before trying AR-15 aluminum lowers. Everything went well except a couple of minor marks where I probably should have cleaned out the shavings more often. So, anybody who views this thread, know that the 5D jig works on Polymer 80 frames quite nicely. I throttled the Makita router down to its lowest setting and it machined the plastic quite well with no melting or hot spot marks.
However, there was a somewhat significant issue in the final steps when drilling the larger safety hole, due to it being Polymer and the aggressiveness of the 5D supplied drill bit. I already felt a little uncomfortable drilling this larger hole into plastic with larger bits. And I wasn't let down with my concern. When drilling the hole on the right side of the frame where the safety detent is located, the plastic is very thin inside. When the rotating drill bit cleared into the milled trigger pocket, it blew out some of the plastic tube area where the safety detent resides. The top half area of the detent chamber is blown out with the lower half still intact. The safety still functions and the detent doesn't fall out, but I want to repair the top portion with JB Weld so the bottom half doesn't stress crack and break off over time.
In hindsight, I probably should have drilled the side holes first and was considering doing it, but went with their instructions instead of my instinct. But, their instructions were on a aluminum frame, not plastic. I still question whether drilling the holes in the side as the last step in an aluminum frame is wise. The only reason I could see not drilling the holes first is that the router bit may hang or grab on a burr or portion of the pre-drilled hole as it passes by milling the inside pocket.
So, I have two questions:
1. What type of JB Weld would you purchase? (I will mix in some of the frames plastic shavings from the milling process.)
2. Is there anything that JB Weld WILL NOT stick to? (I would like to stick a dowel or something non-stick into the detent cavity before building the JB weld puddle and shaping it around the dowel.)
I have little experience with the various mixes of JB Weld, other than using the old school Black and Gray stuff in two separate tubes which you mix on a piece of cardboard. There are several epoxy versions it appears that are specifically for plastics or polymers, but I have no clue which is best.
Thanks for any input you can offer.
