No.215
>>214shouldn't you be able to find detailed and exact measurements of all the receiver components online? I would think that this "approximation then refine" strategy would be a huge disaster and time suck
No.216
would anything in ar180s.com be helpful? eg:
ar180s.com/project-sa80-l85a2-freecad-fusion-360-parametric-design/
ar180s.com/more-ar-180-upper-news/
No.217
>>216>would anything in ar180s.com be helpful? eg:extremely helpful. im already in correspondence with Rick Kelley (the site owner) by email
>>215>I would think that this "approximation then refine" strategy would be a huge disaster and time suckwhy?
a time suck sure, but not that much of a time suck. I wouldn't build a whole rifle on my first receiver, presumably i'd be able to refine it before then
certainly not a huge disaster. its how many obscure homebuilt rifles are made, and when things are hand fit nothing really matters that much anyway because you're fitting on the fly
No.218
>>215>>215>would be a huge disaster and time suckthis nigga built a watch
a watch
No.225
getting some inconsistencies regarding looking at the flats. my reference flat is slightly different than everything else ive seen
No.226
30 dollars to get it 3d printed
overall dimension not actually that big
a tad over 7 inches long, less than an inch and half wide
might by one of those nodak spud receivers soon and print out a trunnion and receiver to check dimensions
No.238
developing some tolerances right now for parts.
need to buy the lower receiver to get a better idea of the upper receiver dimensions
No.239
not to get ahead of myself, but im thinking the way the trunnion is set up can be simplified. having it set up to take your standard AR15 barrel would be a plus, except theres not enough room for the index. would have to redesign how the handguards go on to. probly make them split on the other plane for simplicity sake
No.461
i must have been posting all my updates in spee because none of it is here
just spend the night having serious autism and designing what im hoping will be my bending jig
i got inspired and doin my own design. will see if thats a mistake or not
No.463
>>461mmkay keep us updated OP
No.464
>>463ive got most of it modelled out, pretty fun to look at.
No.494
just list everything ive done since 2019:
>switched to solidworks, remodeled everything
>multiple 3d printed iterations of receiver and trunnion to narrow down the placement
>MJF printed buttstock, buttpad, prototyped a rear sling swivel to stop stock rotation
>95% modeled handguards, heat shield, front sight block, handguard retaining ring
>picked up an AR18 front sight
>found out the AR18 gas block diameter is way smaller than an ar180
>need to either reprofile the barrel (its an insane heavy bull barrel) or get a new one
>getting new one would be the simpler and possibly cheaper option
>also wouldn't have to headpace it which would make life easier
>guess i could sell the ar180 barrel?
No.495
sorry i mean ar180b not ar180
No.576
might makes some changes to the paper. not liking how i describe the setup, not clear
No.583
>>582Looks cool. You making a book for it?
No.584
>>583no its just an internal paper to document how i arrived at the K-factor. its very useful for me to use as a reference for anything related i eal with in the future
i would like to write a book or manual or something along lines of 'a case study in homemade firearm manufacture'– they could go in there i suppose
No.586
made the proper punches today, need some adjustment. one of them needs significant adjustment (i completely messed up the size on accident)
No.587
>>586mess them up on purpose next time
No.594
>>587but that would be a complete waste ;_;
No.614
>>611>>613cool
>taught myselfiata but this seems like the kinda shit that would be way beneficial to have an experienced bloke (muscledaddy) show ya the ropes, for sake of time, wasted materials and keeping your fingers? like apprenticeships r gud n stuff
does this makerspace where you have access to this stuff make you sign waivers before turning you loose?
No.615
>>614im smart enough not to kill myself or destroy equipment
but ya it is pretty dangerous theres zero supervision or training and the only thing they have you do is sign a piece of paper saying you wont use stuff without training and sue if you get hurt
a skilled machinist is pretty cool/admiral, but tbqphwyf being an acceptable 'ok' machnist is pretty easy. the ones i work around are fucking retarded.
No.616
what are you gonna do for the ramrod
No.617
>>616the oprod? i nabbed one along with piston/cylinder a while back
i could pretty easily make an op-rod tho. piston and cylinder would be a lot harder and id have to use a lathe
No.618
>>613looks great. how much time in are you now?
No.619
>>618its taken forever. the design side took a long time to kick off just because i didn't have necessary parts to reference.
all time total? probly few hundred hours?
now that i have the experience id do it a lot different
i'll try and get a successful flat bend for you by next weekend, then if all is well its onto the cam pin rail and trunnion
No.622
i used to fabricate my own parts then i took an arrow to the knee
No.627
>>625rod that you ram into your gun
No.645
>>619as an update that flat bend wasn't successful, but it was relatively close
the problem is my rubber forming technique iw as using didn't work well when scaled up to 8" of length
it did the long flange no sweat, but failed on the short one
decided i'd change my bending jig to be a vice, can bend into it to get most of the angle with a thinner rubber sheet, then shut the vice to get overbend/complete the bend
been spending the past month and half making the vice, is almost done. just some finishing stuff and the jaws are left. hopefully it works
No.646
>>627rod that i ram into ur mom
No.652
Wait how did you get autocad at home?
No.653
>>652just download a student version for free if you have a .edu email
or download a cracked version
or dont. i dont use autocad anymore i use solidworks because thats what i use at work
for free stuff just use fusion360 (not a fan but it has good features, trying to suck you into their product sphere) or one of the FOSS ones
No.656
>>655no for froot smoothie and shorkcel's choco pb protein shakes
No.657
>>653There's no student version of SOLIDWORKS?
No.658
>>657yes there is fucktard you can buy a student license for 20 bucks
No.662
>>659You make that metal yourself or did you buy it from a store?
No.665
>>659did you complete the jaws yet and do you think it will slip during bending
No.670
>>665yes and not sure yet
my next step was to make something for alignment of hte punch (make sure the punch doesn't flip to once side or other during bend)
so i bought some 15 series aluminum extrusion. will allow me to make a supporting frame under it, and also mount some studs that i can slide to a desired position and use as a guide pin. the stud can also be removed and a bolt put in place through the punch to hold the flat down as the jaws are getting tightened.
also i cant find my crescent wrench.
No.672
>>671shutup and make me some more cookies
No.673
the aluminum extrusion came in, i put it all together its not bad. clunky and not refined but i think it will work
have to go tomorrow and modify (extend the length) of my punches to sync up with the guide rods now
No.674
whyd you make this thread in 2019
No.681
>>674its taken forever.
makin the 2nd version of my rib forming die now, probly be done with it on…. this weekend??
No.683
>>681>its taken forever.ask for help and stop doing everything by yourself
No.684
>>683>ask for helpit kinda defeats the purpose of why i do this stuff tho, which is mostly self improvement
theres also the problem of legal quandries particular to my state. my long term goal for this is to have a complete technical package that i can release onto the internet ala the 3d printed firearm scene
think fully toleranced drawings for the upper, lower, and jigs needed for manufacture
No.686
>>684you're just too arrogant to ask for help
No.690
>>684>it kinda defeats the purpose of why i do this stuff tho, which is mostly self improvementu get better when you learn with other people budy
No.692
I can build my own gun. I don't need any help. Leave it alone
No.699
>>690its not a hobby that would be smart to do with others, i have a single trustworthy friend who is also an engineer with an interest in firearms and we typically discuss stuff every other day, but its the kinda thing that will become legitimately dangerous to start involving random people IRL
No.702
>>699you just dont value friendship enough
No.704
>>702im going to finish machining my rib forming die version 2 tomorrow, if im done early enough i'll post pictures of all the stuff i have backlogged
No.705
>>704when do you plan on finishing machining your rib forming die version 2
No.707
>>706all right and what happens if you're done early
No.711
>>707i'll post pictures of all the stuff i have backlogged
No.714
>>705>>707ok it didn't happen today because the gf wanted to make a pie so i had to stay home and do that instead. maybe i can do it tomorrow? idk this fucks my schedule up ngl
No.715
>>714so why did you stay at home dealing with some bitch instead of working on your project
No.718
>>715because
wtf retard, ask me if it happened so i can respond "ok it didn't happpen today" then you can ask why, then you can ask when i might do it next, then you can ask if it messes with my scheduleugh way to fucking ruin everything No.722
>>718what kind of pie was it
No.723
>>722we made a pie with pizza filling
so i guess basically deep dish with a crust?
red sauce, pepperoni, italian sausage, green bell pepper, lots of motz
No.724
>>723did you save me a piece? haha
No.725
>>724all gone.
finished the rib forming die yesterday, if im not lazy i'll post picture
No.731
So to resolve the bending jig issues, I came up with a bending jig/vise/alignment frame concept for future bends. A thin sheet of rubber will be used stop it, and a bend goal of about 70-80% with the press. Then the piece will be bolted down, press removed, and the vise used to bring them the rest of the way in a controlled manner.
The other thing was building a new better rib forming die. I designed it then machined it in a couple sessions the other day. Today I tested it.
Results were good. Some minor nitpicks, but the depth is consistent, alignment acceptable, and edged fairly crisp. Forming the linger rib seemed to require slight more pressure then was available, however, because it didn't flatten the sheet back out at the end of forming.
The forming tool itself is kinda cool. Inserts held in place with setscrews, and in this case the inserts can be flipped around and combined with each other for different lengths/end positions etc. Is sort of slick
No.736
>>723>we made a pie with pizza fillinghow'd it taste?
No.737
>>736pretty good, the mix of pepp, sausage, and green bell peppers was pretty godly tbh
those bell pepps really add a lot when they get cooked
No.738
stopped by yesterday and attempted a bend without the UHMW pads
blocks still slipped, so going to have to do something else.
probly just make a "positioning" plate that has the purpose of putting everything the right distances, and will keep the blocks in place by putting the bolts in shear.
definitely not ideal loading, but i'll do some math to make sure nothing gets too crazy
No.739
>>738nothing is worse than slippery blocks shorkcel
No.740
>>739ya its kinda crazy how little lubrication is needed to bring steel on steel down to a relatively low static friction coefficient
No.745
>>740I know right. me and you have a lot in common we should be friends
No.746
>>745wow really maybe we can read a LN together
No.747
>>746ask your MAL friends to read it with you
No.758
>>757>day skinyeah
we need to talk about your 23andMe results
No.760
notes for next attempts:
- prevent mid beam deflection by making a 1/8" steel flush pressure pad along with some flat head retaining screws
- make a section profile spacer plate to prevent overbend during second bending (in the future, combine this with the punch)
- adjust flange length for a perfect seam upon final bend (for fusion butt weld with TIG)
also adjust 1 & 2 for existing bent flat before moving on to next steps
No.761
some other stuff ive noticed
radius on the rib side is slightly crimped
tube is not square, especially on the front (its like a parallelagram). this likely happened because the bends happeed unevenly, and one side got overbent significantly
the guide rod base has a cutout at the bottom to accomodate overpen from the weld seam
i might have to increase the size tolerance for my tube to account for manufacturing defects
No.762
also after measurement, opening still isn't opened the same, in the middle inch, over .01" difference in width
No.763
>>761yah we know you love increasing size tolerances for tubes
No.770
update?
No.771
>>770i opened it up a little more, but it still wasn't square (needs to open more)
i might go tonight and do that, i'll bring my calipers and actually measure one side to the other
No.773
ok i've got updates, will post later sunday
No.778
>>776looks great, can't be too far off now right?
No.779
>>778nope its gettin real close.
still big hurdles ofc, but the bending stuff is the hardest and most involved.
the other stuff is just tedious machining (machining trunnion, machining front sight block, etc)
i'll 'finish' this one (i'll make simplified components with the critical features on it) so that when i do my next one, i'll have everything figured out and it'll be nice
No.797
>>791Can you reuse any of the material you goofed on?
No.798
>>797I can reuse some of the tooling, if you mean this receiver nah not really but that's ok
I have a pretty good feel for what not to do, so chances for the next one to be near production quality will be good
No.802
>>798Thats cool. Making mistakes is a corner stone of learning. Its pretty impressive what youre doing.
No.805
>>802thanks
its been a really long time doing this project on and off
tonight, i will try to machine the trunnion
No.807
ugh nvm wont happen tonight
tomorrow, if im lucky
No.809
ok well i went sunday, almost got it done but accidently scrapped it
unfortunate but i know what to avoid next i suppose
No.811
>>809What happened that made you have to scrap it?
No.813
>>811so i did the press fit stuff perfect
when i was cutting the features on the bottom my endmill slipped in the collet and i lost some Z without realizing it
it was probly because its a pretty dull end mill, the collet may have been dirty too
anyway i broke through the press fit wall of the trunnion
also snapped the shit out of my 1/4" endmill on a plunge lel
i'll probly post a pic at some point
No.815
>>813trying again tonight
No.816
FUCK this is gay
tire blew out on the way
so bad the mexican shop in the bad part of town wasn't even willing to patch it
gay gay gay gay gay
No.817
>>816>not even the Mexicans will patch itlelelelel