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rump buttman
Feb 13, 2018
Probation
Can't post for 19 hours!


22 Eargesplitten posted:

McNally's great joke aside, that's interesting about the divot depth. I haven't used one myself, I'd like to join a makerspace at some point but LOL Corona. I am not terrible with 3D modelling, but my control with hand tools sucks so telling a computer what to do is appealing to me. I wonder if the more modern machines will adjust amperage during the manufacturing process so that you do the main cutting at a higher level for speed and then do the final touches at a lower level to smooth it out. That also gives you the advantage of not having to do anything else to harden the material, although I don't know if only having surface hardening on a gun part would bite you in the rear end longevity-wise.

EDM is a art. Prefacing again, new machines from Sodick or AgieCharmilles are black magic good. They are as modern of tooling as you can get and do things beyond what I am accustom to. They are a pinnacle of modern engineering. Regarding them, my infoís dinosaur poo poo.

The machine I worked with are analog motherfuckers. Toggle switches, hand wheels, pain in the rear end spindle to center on. I am talking about the best motherfucking machine out there. Eltee Pulsitron model trm 330. West Caldwell, NJís finest.

Created by a Tool & Die company to solve a few problems including but not limited to; gently caress my tap busted in something I have thousands of hours into and how the gently caress do you put a square hole into steel? These cleaver jersey slobs made a machine that featured a Swiss fehlmann table with tenth vernier scale hand wheels, a pulse timer with millisecond increments for both on and off for up to a second, amp control from .5 to 30 by .5 amp increments, gap voltage, retract time, switch polarity and set gap condition. Eltee did it all and it did it with style.

First rule, only burn what you have to when you have to. Itís slow.

Now, how you set this machine can make it cut differently. Like you alluded to, you take different parts of the cut into account and adjust settings and electrodes accordingly.

Have to burn a lot? Crank the amps for maximum speed. Burn motherfucker burn.

Have to but delicate? Waaaaaaaaaaiting is the hardest part....

When the juice is flowing, you need more gap between your electrode and workpiece. The gap is were the spark lives. Shaq sized sparks needs a shaq sized gaps.

So, you need a bigger gap, but need to keep a precise tolerance? That means your roughing electrodes are smaller in dimension to accommodate more gap.

Finish electrodes usually have less juice ran through them and are bigger. Plus your roughing electrode is going to erode a lot, gotta have a fresh one to make it precise and pretty.

You generally have a series of electrodes to make a precise burn, usually with varying dimensions. Sometimes you break down complicated geometries to a series of simpler geometries in a burn. Sometimes you orbit a weird geometry to make weirder geometries. Sometimes you can grind the worm electrode to sharpen it. Itís an art.

This gets into the question where the gently caress does all the material go?

Swarf.

Those tiny ball bearing blasted off the work piece mixed with graphite from the electrode. As this build up between your electrode and work piece this poo poo arcs you out and the burn does not go on. So what do you do?

Flush.

I am going to let you in on a little secret, no clicks necessary. EDM itís all about the flush.

You design your electrodes with plumbing to run the dielectric fluid through. It comes out between the work piece and electrode to push the swarf out.

the second rule of EDM, the electrode only burns where it is.

So these flushing holes leave posts. In the series of burns you off set your posts (to knock down old posts. Usually trying to hide the last posts. One example of this would be a mold maker aligning a electrode flushing hole with an ejector pin locations inside the freshly burnt plastic cavity.

Now, all those other settings, gap condition, retractions, electrode pulses, those are all there to find the flush to stop the arcing. Sometimes you are fighting and fidgeting for hours to get the burn done.

When itís burning real good, it sounds like frying eggs.

Other cool things about EDM? Hardened D2? Burn it. Carbide? Burn it. Itís slow as gently caress, but you can burn it. Softer stuff burns faster. Harder stuff still burns.

Now, modern machines get a tool changer loaded with a series of electrodes made by CAD that bust out perfect gaps with corresponding setting and can burn unattended in sequence and probed for dimesional feedback. All for somewhere in the range of $house in Wichita to $house in NYC.

As far as guns? I donít know squat. The hardness doesnít go too deep. And with the slow nature of edm, I donít see it useful on to many features (I am aware of) beside porting or wire edm pieces that would be really hard to mill/turn. Itís slow and expensive.

I also donít know much about mass manufacturing beyond my little niche. I just have a tiny bit of experience building custom molds in tool & die job shop made of dinosaur bones. To all the engineers out there, all fields. learn how to draw a loving drawing. On average, yíall suck dick at it.

-phone posted with beers, not going to edit. Yíall can decipher.

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boxen
Feb 20, 2011


rump buttman posted:


-phone posted with beers, not going to edit. Y’all can decipher.

I dig it.

Cyrano4747
Sep 25, 2006



rump buttman posted:


-phone posted with beers, not going to edit. Yíall can decipher.

Not bad but you have a way to go if you want to master incomprehensible drunk posting.

Styles Bitchley
Nov 13, 2004

FOR THE WIN FOR THE WIN FOR THE WIN

rump buttman posted:

I also donít know much about mass manufacturing beyond my little niche. I just have a tiny bit of experience building custom molds in tool & die job shop made of dinosaur bones. To all the engineers out there, all fields. learn how to draw a loving drawing. On average, yíall suck dick at it.


Solid Edge monkeys or internet designers maybe. But engineers that actually understand how things are made are usually good. But it's not surprising so many companies have "shop drawings".

rump buttman
Feb 13, 2018
Probation
Can't post for 19 hours!


Styles Bitchley posted:

Solid Edge monkeys or internet designers maybe. But engineers that actually understand how things are made are usually good. But it's not surprising so many companies have "shop drawings".

ďShop drawingĒ swindlers are lovely. Send over a three view with certain features not called out so that they can try to dupe someone into a bad bid? happens more than it should.

I am not drunk posting talking about those. Iím talking about not measuring off center or not organized call outs that are easy to read. Stuff like that. Fundamentals. Somehow this get through 3 levels of learned engineers at engineer building sized firms.

Iím my region there are ~5 engineers that I get prints from that are real good. Itís who weíd send MR INVENTOR to work out ideas with. Those dudes are very solid drawers along with being very solid engineers.

At the end of he day it doesnít matter if the engineer can draw if they have a model they can send me. It just wastes more of my time.

shalafi4
Feb 20, 2011

another medical bills avatar

rump buttman posted:

ďShop drawingĒ swindlers are lovely. Send over a three view with certain features not called out so that they can try to dupe someone into a bad bid? happens more than it should.

I am not drunk posting talking about those. Iím talking about not measuring off center or not organized call outs that are easy to read. Stuff like that. Fundamentals. Somehow this get through 3 levels of learned engineers at engineer building sized firms.

Iím my region there are ~5 engineers that I get prints from that are real good. Itís who weíd send MR INVENTOR to work out ideas with. Those dudes are very solid drawers along with being very solid engineers.

At the end of he day it doesnít matter if the engineer can draw if they have a model they can send me. It just wastes more of my time.

I used to run a student machine shop at Ohio state.

In the ~12 years I was there I had ONE student/prof/researcher bring me a set of drawings that were dimensioned correctly right off the bat.

She was a PhD student that had done design work for ~5 years before coming back to school.

Also was the only person to stop by the shop before she did her drawings to see what equipment we had and designed the parts around that.

Made our job so much less infuriating.



Right before I left, there were serious discussions about having me teach an actual drafting class. What shot it down was the 3d modeling prof bitching that I'd be stepping on toes and didn't have a PhD so I couldn't teach.

Flatland Crusoe
Jan 12, 2011

Great White Hunter
Master Race

Let me explain why I'm better than you


rump buttman posted:

ďShop drawingĒ swindlers are lovely. Send over a three view with certain features not called out so that they can try to dupe someone into a bad bid? happens more than it should.

I am not drunk posting talking about those. Iím talking about not measuring off center or not organized call outs that are easy to read. Stuff like that. Fundamentals. Somehow this get through 3 levels of learned engineers at engineer building sized firms.

Iím my region there are ~5 engineers that I get prints from that are real good. Itís who weíd send MR INVENTOR to work out ideas with. Those dudes are very solid drawers along with being very solid engineers.

At the end of he day it doesnít matter if the engineer can draw if they have a model they can send me. It just wastes more of my time.

Drawings donít come from experienced engineers, itís the economic reality of the situation. They get cranked out by ďdraftsmanĒ with a few credits of community college, engineering co-ops or fresh out of school engineers who took 130 credit hours, 3 of which involved some CAD package taught by a TA that took the class the semester before. Drafting is time consuming and no one is going to spend the $200/hour that a licensed PE bills at when you can crank out mostly as good prints for $50-$75/hour.

The experienced engineers with any degree of social skills get moved into management and squander their technical prowess on PowerPoint Presentations, Excel charts of Budgets and Microsoft Project schedules. They manage the big picture ideas and check engineering work occasionally during the 15 minutes a day they arenít resolving a bigger issue like the million dollars worth of equipment that wasnít built to specification not scrutinizing the inside radius of a keyway cut on a widget that cost a few thousand dollars to machine. On top of the time issues a lot of older engineering managers never learned 3D modeling and arenít as hands on as they would be with AutoCAD or hand drafted prints (Iím not joking on this one).

Shaocaholica
Oct 29, 2002

Fig. 5E


I did 4? Years of drafting between middle school and high school. Was pretty fun with the class of Ďbad kidsí trying to do their best and shouting expletives every time they got a good line in.

The whole computers thing will solve itself with time. Probably to the detriment of non computer design and low level fundamentals.

rump buttman
Feb 13, 2018
Probation
Can't post for 19 hours!


I hear that about economies of time/skill and wave of the future stuff. Modern machines are crazy good and talk in binary. Communicating with machines has been the focus of design. Way more efficient work flow, need less skill labor, and dead nuts. The chumps and kids end up doing the busy work to accommodate bids before releasing the model to the manufacture. Some companies will give the model upfront, some are weird and wonít release until after you win the bid.

My grievance was aligned with shalafi4s experience. People like that woman are rare. I wish I could only work with people like that. That little bit of mindfulness saves hours. I figure when I design a mold, for every hour I put into refining my design, I save a few hours on the shop floor. Having an engineer recognizing the real limitation and incorporating them into their design is not something Iíve ran into. Iím jealous as hell.

Like flatland gets at, a juggernaut like that baller rear end woman, with experience and useful social skills will probably got swept up to PM two weeks ago. with a Her skill set and experience she needs to care about things a lot more pertinent to the projects. For drat good reason.

The second part of my grievance is the Education part of it. Like you guys point out, drafting just isnít taken seriously at any level. Classes full of dumbasses in HS (I was one of those dumbasses) or 3/130th of your credit hours at university with the modelers elbowing drafting. Departmental resource wars canít be rare.

Itís just annoying because the fundamentals arenít that hard and save a lot of time. Itís a better form of on the floor communication. I like a good print for one off, & prototype stuff way more than a model. I think itís more elegant communication when done right. For me, a good print letís me digest the doodad quick. Models are great for a litany of reasons. Itís just annoying that drafting isnít taken as serious as my super hella smart brains wishes it was.

rump buttman fucked around with this message at 18:28 on May 12, 2020

Wiggity
Oct 22, 2016

Old school cool
Now with all of the millenial bullshit

I LOVE welding on things where chlorinated solvents are present - Phosgene ams your friend!


Even when it comes to welding, blueprints/drawings are crude and often horrible. I fully realize that building a table from square tubing is significantly different from blueprints that incorporate precision machining, but I have seen some seriously bad work. I also recognize that there is usually a welding engineer on site when it comes to code governed structural or pipeline work that can simply tell a welder what to do, practically removing blueprints from the equation.

I once had an engineer hand me a literal napkin that came with his lunch with a drawing of a fixture he wanted built. It was a single front view drawing that gave me no clue what was actually wanted and also had no indications of where the welds were actually supposed to be placed. Just an iso view would have been much more informative... Seeing as how he was on lunch break for the next hour, I did my best but hosed it up inevitably and wasted about an hour of time if you count me having to rebuilt it later and material to boot.

Now that I do my own custom fabrication, I try to do my own drawings of pieces that I like and plan to replicate in the future. Don't get me wrong, it starts with a horrible iso sketch that is prone to changes but if I dig the completed product, I spend the time producing a 3 view + iso drawing that I still inevitably make at least one mistake on but the practice is great considering that I only took one blueprint reading class in college and have no formal drafting experience.

Styles Bitchley
Nov 13, 2004

FOR THE WIN FOR THE WIN FOR THE WIN

Flatland Crusoe posted:

Drawings donít come from experienced engineers, itís the economic reality of the situation. They get cranked out by ďdraftsmanĒ with a few credits of community college, engineering co-ops or fresh out of school engineers who took 130 credit hours, 3 of which involved some CAD package taught by a TA that took the class the semester before. Drafting is time consuming and no one is going to spend the $200/hour that a licensed PE bills at when you can crank out mostly as good prints for $50-$75/hour.

The experienced engineers with any degree of social skills get moved into management and squander their technical prowess on PowerPoint Presentations, Excel charts of Budgets and Microsoft Project schedules. They manage the big picture ideas and check engineering work occasionally during the 15 minutes a day they arenít resolving a bigger issue like the million dollars worth of equipment that wasnít built to specification not scrutinizing the inside radius of a keyway cut on a widget that cost a few thousand dollars to machine. On top of the time issues a lot of older engineering managers never learned 3D modeling and arenít as hands on as they would be with AutoCAD or hand drafted prints (Iím not joking on this one).

Yeah pretty much. I work with all those types, we have a few draftsmen/designers that are REALLY good with models and drawings. And some that have plenty of training and decades of experience and are still not very good. That just comes down to attention to detail and the right person for that type of work. I just hate getting into debates like "should this be a concentricitiy or runout GD&T callout???" when I'm more worried that you have 4 place decimal tolerances on noncritical dimensions or you put draft angles on a machined part....

Shaocaholica
Oct 29, 2002

Fig. 5E


I came across a drawing for an AR lower and it was a bit confusing because it only had 1 datum which is fine I guess but every feature was measured from another feature and not directly to the datum so in order to find out the offset from the datum I would have to work backwards feature to feature and that just seems a bit over complex?

SwissArmyDruid
Feb 14, 2014



Admittedly, I work in Silicon Valley making parts for semiconductor test equipment for companies you have heard of.

But the number of times I have had to deal with loving press-fit dimensions that are +/- .0005 between a goddamn socket backplate and the standoffs is enough to drive me up the wall.

Not the Z-height between the backplate and the back of the board as-dictated by the standoffs. No, the diameter of the standoff and the diameter of the counterbore that the loving standoff press-fits into.

I want to shove progressively larger rods in .0005 increments down the engineers' urethras, loudly demanding that they answer whether or not we've hit interference fit yet.

Styles Bitchley
Nov 13, 2004

FOR THE WIN FOR THE WIN FOR THE WIN

SwissArmyDruid posted:

Admittedly, I work in Silicon Valley making parts for semiconductor test equipment for companies you have heard of.

But the number of times I have had to deal with loving press-fit dimensions that are +/- .0005 between a goddamn socket backplate and the standoffs is enough to drive me up the wall.

Not the Z-height between the backplate and the back of the board as-dictated by the standoffs. No, the diameter of the standoff and the diameter of the counterbore that the loving standoff press-fits into.

I want to shove progressively larger rods in .0005 increments down the engineers' urethras, loudly demanding that they answer whether or not we've hit interference fit yet.

Yeah but tighter tolerances always means higher quality, right??? #IWANTSUPERPRECISION

Everything works on paper(or the model). I often tell people that yes, we can make it like that. Maybe find a contractor doing work for NASA. No, we cannot make it like that and be competitive.

My favorite is when I see like a vanilla sheet metal bracket or something that has some really generic length and width and all the other dimensions off the wall like like 48į bend angles and you know they just let the software generate all the other numbers and said gently caress it.

Then you have the people that create what we call "cartoon drawings" that draw some complicated assemblies, maybe based of someone else's design, that just have a few key top level dimensions and a bunch of them are reference. QA guys freak out when the part doesn't work but there is nothing to reject it against.

shame on an IGA
Apr 8, 2005



Javid posted:

Kinda taking a wild shot in this thread, but - anybody familiar with having large equipment shipped?

The specific end goal here is to find a company that I can give a piece of extremely nice furniture to and have it get across the US without getting hosed up. There are a shitload of google hits for freight companies and I have no idea how to narrow down that firehose of information so I'm hoping somebody who's bought yuge objects like lathes will have a clue.

As has been said riggers are not gentle and freight company liability caps out at something like $0.20/lb. You need to be talking to a moving company.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf



Because I have apparently angered God and nothing can ever be easy I need to figure out a way to replace this broken hammer spring. It's made using 17 gauge wire which apparently barely exists. loving Austrians. How hard is it to make a torsion spring if I can get a hold on some proper wire?

edit: I ordered $11 worth of wire so that's probably enough to make new springs for all currently existing Steyr GBs. I need a right hand wound torsion spring with just under five coils with a 5/16" inner diameter. 315 degree free arm position with a 90 degree bend on the close arm. How hard could it be? Maybe I can make some extras and sell them

my kinda ape fucked around with this message at 06:52 on May 20, 2020

22 Eargesplitten
Oct 10, 2010

Also sexism, religious bias, jingoism, and so on. Don't do it, people!

Dogs, don't do it either, even if the police man really tries to train you to do it.



FWIW torsion springs seem like the easiest ones to make by hand because the coils are right up next to each other, no need to worry about even coil spacing, and measuring the degrees is probably even easier with some $5-10 electronic tool than it was with a protractor.

If you don't have a 5/16" rod handy (it's a pretty common punch size, I think?) you could always go to a hardware store that has the individual bolt bins and just find a partially-threaded bolt with a 5/16" diameter.

armorer
Aug 6, 2012

I like metal.

You may need a 1/4" rod (or 9/32") instead of a 5/16", because of springback.

22 Eargesplitten
Oct 10, 2010

Also sexism, religious bias, jingoism, and so on. Don't do it, people!

Dogs, don't do it either, even if the police man really tries to train you to do it.



Fair enough, he probably knows what he's talking about more than I do. I'm trying to find springs for my guns and looked into winding them myself, but those are compression springs, which seem like a major pain to make well.

armorer
Aug 6, 2012

I like metal.

I've just wound a lot of wire for unrelated metalwork projects. When you coil wire like that it never ends up with the ID of the rod. The instant you release tension it relaxes away from the rod a little bit, with "little bit" depending on essentially every little variable (material, temper, wire guage, rod size, etc).

Cyrano4747
Sep 25, 2006



Are you going to need to heat treat it after the winding?

You should document this. It would make a hell of a thread.

Why no I have no personal interest in knowing how to make my own obsolete springs for obsolete auto loaders why do you ask?

Styles Bitchley
Nov 13, 2004

FOR THE WIN FOR THE WIN FOR THE WIN

I mean if you can simulate the rounding that a spring form machine would do, and apply enough pressure, it should work. Just wrapping it around a rod is not going to do well as you have to permanently deform the wire all around evenly. That is what the machines do.

I have to ask, but you did contact Steyr USA and see if they can source this spring for you? Wouldn't hurt to ask Wolff to quote it, maybe can find other owners to go in with you.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

I figured I would give it a go before I asked a company to make me 500 of them for the same cost as the gun itself. Wolff only does custom orders for "production quantities" and I'm sure other places are similar. One place has a minimum $500 setup cost posted and that's before labor and materials.

How bad are my results going to be if I just wrap it tight around a rod? It fires like 90% of the time in single action with only the one spring doing anything so I figure if I can get something that fits and exerts like half the force the factory spring would then it'll probably be perfectly reliable with new ammo that has soft primers.

No idea about heat treating but I did see it mentioned in a tutorial someone made about making torsion springs. This is all completely new to me tbh.

Cyrano4747
Sep 25, 2006



Also google around and see if you can find any specialty forums for it. Gunboards probably has a subforum that would include people who know way too much about them.

Basically put out some feelers and see if thereís some old collector out there with a bag of spares or info on another spring that works well enough for range toy use.

Donít be put off if the forum looks dead. A lot of those boards donít see much posting but the dudes who inhabit them seem to F5 a lot.

armorer
Aug 6, 2012

I like metal.

If you know any reasonably serious knife makers, they likely will have a small heat treating setup for blades and may be able to heat treat a few springs for you.

If you already have the wire it seems like you may as well give it a shot. You don't need to consistently make thousands of them that work well, you only need one in ten to work well so you can put it in your gun and be done with it.

Flatland Crusoe
Jan 12, 2011

Great White Hunter
Master Race

Let me explain why I'm better than you


my kinda ape posted:

I figured I would give it a go before I asked a company to make me 500 of them for the same cost as the gun itself. Wolff only does custom orders for "production quantities" and I'm sure other places are similar. One place has a minimum $500 setup cost posted and that's before labor and materials.

How bad are my results going to be if I just wrap it tight around a rod? It fires like 90% of the time in single action with only the one spring doing anything so I figure if I can get something that fits and exerts like half the force the factory spring would then it'll probably be perfectly reliable with new ammo that has soft primers.

No idea about heat treating but I did see it mentioned in a tutorial someone made about making torsion springs. This is all completely new to me tbh.

If you just cold work it it will be fine or it will break and you try again. Maybe you get a slightly different variant of spring steel and try again. The heat treat is just relieving stress in the material which may or maybe not be needed and IMO you arenít going to have great results heat treating a spring with readily available tools at home.

Heat treating is tricky business even with precise tools and controls. Iíve built industrial heat treat furnaces and Iíve seen plenty of metallurgist with graduate degrees stumped by the process.

Honestly I would consider measuring the spring as best as possible and start looking for close alternatives from Wolff or McMaster Carr. You best bet is to find an existing product that is close.

shame on an IGA
Apr 8, 2005



This Old Tony has a video for people going this road with some useful links, especially the calculator that figures out what diameter your winding mandrel needs to be to account for springback.


https://www.youtube.com/watch?v=jAawhg6JtyY

http://myvirtualnetwork.com/mklotz/

Wa11y
Jul 23, 2002

Did I say "cookies?" I meant, "Fire in your face!"

If you haven't, I'd recommend checking with Numrich, except they're in NY so they're shut down (I have a $12 order waiting, and plans for a $65 order when they fi ally open back up). They usually have some esoteric parts available.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

shame on an IGA posted:

This Old Tony has a video for people going this road with some useful links, especially the calculator that figures out what diameter your winding mandrel needs to be to account for springback.


https://www.youtube.com/watch?v=jAawhg6JtyY

http://myvirtualnetwork.com/mklotz/

This is extremely helpful, thanks!

Numrich doesn't have any GB parts (although they have a couple Rogak parts???) but I suppose they might find an equivalent spring somewhere. I have an order with them already for some M1 carbine stuff and I figure they won't be open for a few weeks at least.

I should send Steyr USA an email asking but unless they have a vast warehouse of random crap I think it's pretty unlikely they'll be able to help me.

Grainger is shipping me some wire so I'll see if I can bend a reasonable facsimile without losing an eye.

my kinda ape fucked around with this message at 23:11 on May 20, 2020

bred
Oct 24, 2008


I've made some springs by hand and it goes pretty quickly so you can make 10 or 20 to get a good one. I used drills (backwards) in a hand drill and stepped through the drill index to adjust the diameter. These were for proof of concept nitinol actuators. I was building to a force and stroke requirement rather than a physical one. I did it all at room temp and didn't have any issues. No springs failed and we tested to 100k -10M cycles depending on the customer requirements.

You can check McMaster, century spring co, and lee spring for a range of equivalent springs. I had fun making a spreadsheet and then trying to wind my own to the numbers. I'd tangle the end in the Chuck or even clamp it in there and then go slow. You want the right coil first and then work the ends. Watch the end, it can be sharp.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

Ok so I may have found a workable candidate from Lee Spring: http://www.3dpublisher.net/SWDownlo...2010%20S316.pdf

Part #: LTR045D 10 M

The free angle is 120 instead of the 300-315 I need but I can probably just do another half turn without too much hassle. The legs are longer than I nee so I'll have to cut them off partially anyway.

My main question is...why are there a whole bunch of springs with a 0.312" ID and a 0.045" wire diameter and different ODs??? Shouldn't the OD always be ID+wire diameter x2? Are they just measuring weirdly or documented wrong somehow or am I missing something? It seems like logically any spring with a 0.312" ID and a 0.045 WD should have an OD of ~0.402".

shalafi4
Feb 20, 2011

another medical bills avatar

my kinda ape posted:

Ok so I may have found a workable candidate from Lee Spring: http://www.3dpublisher.net/SWDownlo...2010%20S316.pdf

Part #: LTR045D 10 M

The free angle is 120 instead of the 300-315 I need but I can probably just do another half turn without too much hassle. The legs are longer than I nee so I'll have to cut them off partially anyway.

My main question is...why are there a whole bunch of springs with a 0.312" ID and a 0.045" wire diameter and different ODs??? Shouldn't the OD always be ID+wire diameter x2? Are they just measuring weirdly or documented wrong somehow or am I missing something? It seems like logically any spring with a 0.312" ID and a 0.045 WD should have an OD of ~0.402".

For Torsion springs?

The ID measurement is how small of a shaft it'll still clear when it's fully torqued/compressed. The more the rotation it has to go the farther it has to come down. So a 300į spring will have a bigger OD than a 180į spring that is the same wire.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

shalafi4 posted:

For Torsion springs?

The ID measurement is how small of a shaft it'll still clear when it's fully torqued/compressed. The more the rotation it has to go the farther it has to come down. So a 300į spring will have a bigger OD than a 180į spring that is the same wire.

Ohhhh ok that makes sense! That one won't work then. I realized the OD is actually more important than the ID in this case as the spring kind of rests against some stuff outside of it and the rod that goes through it is significantly smaller than the ID of the spring.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

Ok so I'm learning a lot about torsion springs and springs in general and realizing what I actually need vs what I thought I needed. Also doing some digging of the sparse information available about the gun on the steyrclub.com forums and apparently the later production guns got different springs with different leg angles and supposedly a different wire diameter and 5 1/2 coils instead of ~4.75 which made the double action trigger pull nicer.

(not my pic, but those are the v2 springs I guess, and the spur style hammer instead of the original loop style)

my kinda ape fucked around with this message at 02:57 on May 21, 2020

Vindolanda
Feb 13, 2012

It's just like him too, y'know?


I was looking for someone to make flat spring steel clips for shotgun cartridges a while ago. Couldnít get any, but I did find that plenty of UK companies were happy to do one-off wire springs if they had a CNC spring coiler. Maybe someone like that exists in the US? Often the ones with the most ďprofessionalĒ websites were willing to charge the least, possibly because they arenít as often run by grumpy old gits.

https://www.airedalesprings.co.uk/s...orsion-springs/

https://www.airedalesprings.co.uk/custom-springs/

Just the first hits on google - I donít seem to have any of the quotes I had but most didnít want a colossal amount.

my kinda ape
Sep 15, 2008

Everything's gonna be A-OK


Hair Elf

Vindolanda posted:

I was looking for someone to make flat spring steel clips for shotgun cartridges a while ago. Couldnít get any, but I did find that plenty of UK companies were happy to do one-off wire springs if they had a CNC spring coiler. Maybe someone like that exists in the US? Often the ones with the most ďprofessionalĒ websites were willing to charge the least, possibly because they arenít as often run by grumpy old gits.

https://www.airedalesprings.co.uk/s...orsion-springs/

https://www.airedalesprings.co.uk/custom-springs/

Just the first hits on google - I donít seem to have any of the quotes I had but most didnít want a colossal amount.

I haven't bothered to submit any quotes besides one website that had an instant quote generator. They said about $300 for what I wanted, which isn't outlandish and I could afford but it seems pretty steep to fix a $900 gun. If I could sell some extras from a batch on gunbroker I could make my money back but that would require me to have the other, left hand wound spring made too.

I guess I should just submit some quotes and see what they say. If someone is willing to do it for $100 or less I'd be all over it.

shame on an IGA
Apr 8, 2005



If you're going to have someone else make them for you, go for the production run. This is one of those situations where piece #0001 costs hours of setup labor and maybe some custom tooling while #0002 - #1000 cost a couple inches of wire.

New Concept Hole
Oct 10, 2012

東方動的


Does anyone here have experience with building AKs from a parts kit? I'm looking to do just that but I don't have the major tools to do it, specifically a drill press for drilling the receiver and barrel, and a hydraulic press for pressing the barrel into place. What's a recommended "hobby option" for both of these?

SwissArmyDruid
Feb 14, 2014



Hammer, screwdriver, vodka?

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New Concept Hole
Oct 10, 2012

東方動的


SwissArmyDruid posted:

Hammer, screwdriver, vodka?

I meant more like, what dedicated drill press and hydraulic press would do these two tasks without being prohibitively expensive-- my budget is comfortably in the 2K USD range, altogether.

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