Complexity/cost of making small press die? - Page 2
Close
Login to Your Account
Page 2 of 2 FirstFirst 12
Results 21 to 28 of 28
  1. #21
    Join Date
    Jun 2001
    Location
    downhill from Twain\'s study outside Elmira, NY
    Posts
    11,384
    Post Thanks / Like
    Likes (Given)
    4277
    Likes (Received)
    4055

    Default

    I have not read all the replies, mostly a quick skim.
    2 part (or progressive with more) would be the fool-proof method.

    If that is not within your immediate facility, rubber-form can be very effective, esp if a little post-forming manual massaging is acceptable.
    However, as a quick test, if you decide to see what happens with rubberform/elastomeric, the elastomer for your app would be a pretty hard durometer. Maybe 95 A.

    you can probably get away with just pushing a steel punch into a urethane pad
    ^This won't work^
    The pad must be constrained by a heavy steel ring (& bottom)& not hugely larger than the die
    The elastomer needs to bulge up and over the male form (if the male is pressed from the top) in a way that flows the metal over the edges.
    Pressing the die into soft or unconstrained rubber will not work effectively.

    The more difficult issue might be locating the blank to the die. The closer the blank sheet is to net dimensions, the better. However your part has no intrinsic locating elements. OTOH it is symmetrical enough, and your initial experiments don't seem to show positioning as a difficulty, so you may be ok just placing and pressing.

    smt

  2. Likes Repoman liked this post
  3. #22
    Join Date
    Feb 2021
    Country
    UNITED STATES
    State/Province
    Vermont
    Posts
    10
    Post Thanks / Like
    Likes (Given)
    19
    Likes (Received)
    3

    Default

    Something else I'm considering is trying to make the male and female dies and forgoing the space age looking design features on the top, then pressing those after. I may be able to do that in aluminum (or steel if the Makerspace near me has a DRO on their Bridgeport), the differences in the basic shape don't seem overly complex, I just have to figure out how to deal with the difference in the radii...

    I will definitely try to press in stages with annealing inbetween.
    I did find a place near me that seems to specialize in metal stamping as well, and will have to reach out to them to see what they say (New England Precision).

  4. #23
    Join Date
    Jun 2002
    Country
    CANADA
    State/Province
    British Columbia
    Posts
    3,167
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3058

    Default

    Hi again Repoman:
    You need to pay attention to the kind of brass you use.

    Not all grades are ductile enough to draw.; one of the most common grades that IS intended to be drawn is C260 or "cartridge" brass.
    It is the most ductile of all the brasses and you can get it from Mcmaster Carr as shim stock , so it's almost ideal for your needs and will take the shape you want.
    You will be able to form it in one hit with no annealing, but you'll have to test whether it's dent resistant enough at 0.020" thickness for your needs.

    With regard to the logo on the bottom face; that's not the hard part of this stamping...it's one of the hard(er) parts of making the punch and the die.

    Find a kid fresh out of CAD school and pay him some beer money to model it up for you...a half hour or less should do it nicely.
    Go to your local CNC night school and get another kid to program and cut it for you in A-2 tool steel.
    Go top your local VoTech and have yet another kid toss it in the heat treat furnace for you, or alternatively, take the course yourself at nights and use it as your graduation project; make all the pieces for your die, harden them , polish them and assemble them.
    Or maybe find a local Makerspace and learn that way.
    Find a kid in the moldmaker program at the VoTech and get them to sinker EDM the female logo into the bottom of the die cavity for you.

    In any event; with a little bit of ingenuity, you can build the parts.

    Your BIG problem is to design the die so you know it will work on the first try.
    In my opinion, there is no substitute for an experienced die maker or die designer to do this part of it for you and hold your hand throughout.
    There are a gazillion seemingly trivial small judgements that must be nailed correctly or the bloody thing won't work, and if you guessed wrong and took too much material away somewhere important, cannot be easily fixed either.
    Chasing all that shit down if you've never done it before and have no idea why it won't work is a guaranteed way to make you old before your time.

    Cheers

    Marcus
    Implant Mechanix • Design & Innovation > HOME
    Vancouver Wire EDM -- Wire EDM Machining

  5. Likes Repoman liked this post
  6. #24
    Join Date
    May 2003
    Location
    Lambertville, MI USA
    Posts
    3,019
    Post Thanks / Like
    Likes (Given)
    1714
    Likes (Received)
    1506

    Default

    Quote Originally Posted by Repoman View Post
    I did find a place near me that seems to specialize in metal stamping as well, and will have to reach out to them to see what they say (New England Precision).
    This is a good choice, your going to learn a lot talking to someone that has actually built a draw die. The price your going get get quoted will shock you, Don't think of the cost to build the die but the price per part over the life of the tooling. A well built die for the part you want to make should last at fifty parts a year FOREVER.

  7. Likes Repoman liked this post
  8. #25
    Join Date
    Feb 2021
    Country
    UNITED STATES
    State/Province
    Vermont
    Posts
    10
    Post Thanks / Like
    Likes (Given)
    19
    Likes (Received)
    3

    Default

    Is Rhino3d applicable for CAD/CAM?

    I've been thinking about taking an online course to CNC that seems pretty thorough, although spending a couple grand without getting hands on experience with machines seems kind of a bad deal (the course does seem really thorough overview of machining in general and focuses on specific machines like Mazak, Haas, some stuff with Fanuc...tool geometry, grinding, required/applicable math, material characteristics, etc).

    I definitely can't afford Solidworks, but I realize I do need to get going on CAD/CAM, I've toyed with the idea of buying a CNC router in the past to learn some CNC basics, but don't know if that's really a great approach either.

  9. #26
    Join Date
    Jun 2002
    Country
    CANADA
    State/Province
    British Columbia
    Posts
    3,167
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3058

    Default

    Hi Repoman:
    I played with Rhino way back when and rejected it in favour of Solidworks because I found Rhino to be weak for making the kinds of designs I need.
    But there are lots of people who like it...it seems to be a favourite among jewelers.

    Have you looked into Fusion 360?
    It's the obvious starting place for a lot of people just getting into CAD CAM because it will do both.
    Forget about all the crying and complaining you'll hear about the predatory assholery of Autodesk (the sellers of the software, with a reputation for dickishness unrivaled by just about anyone else).

    I hate Autodick...they're dishonest manipulators, but I need my software to make my living, so being bent over a barrel means different things to me than it would to you, and you may like it just fine.
    The price they use to reel you in with is pretty attractive...the reckoning happens later when you've invested tens or hundreds of thousands of dollars in files and programming and they grab you by the tits and give you a good shaking by turning off your access if you don't pay forever, and however much they decide.
    Last I heard it's a bit buggy and crashy too, compared to more solid industrial grade software, but I don't run it, so I can only gossip nastily about it...I don't actually KNOW.

    If you want to get into metalworking in general and not just solve this particular problem then by all means...go for it.
    But it's not going to take you very far for this problem all by itself...nothing that a CAD kid and a case of beer to motivate him can't solve for you much more efficiently.

    So yeah...if you want to join the metalworking club...come on in.
    But if you just want covers for your pickups, you're picking the long way home.

    Cheers

    Marcus
    Implant Mechanix • Design & Innovation > HOME
    Vancouver Wire EDM -- Wire EDM Machining

  10. Likes Repoman liked this post
  11. #27
    Join Date
    Aug 2005
    Location
    Raymond , CA
    Posts
    397
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    291

    Default

    A quick introduction to the art can be found in the ASM Metals Handbook "Forming and Forging" Ninth Edition vol 14. Take a look at the chapters on Deep Drawing (pg 575 to 590) and Rubber Pad Forming.(pg 605 to 615)
    The handbook can be found at a big city main library

    You need to have a good idea of what the drawing die assemblies look like, what suitable die materials are available, the press construction, and what the process limitations are before you can have a intelligent conversation with a fabrication shop foreman or a tool and die maker.

    For low production runs the die can be a zinc (Zamak) casting poured in a plaster mold. The plaster mold can be copied from your existing prototype part. Zamak has a compressive strength of 80 Ksi compared to the 5 KSI of a filled epoxy.
    The punch can also be a zinc casting formed in a plaster mold with the appropriate clearances, machined from a easy to work tool steel, or if the draw depth is within limits replaced with a rubber pad.

    Your objective is to produce a low volume low cost part. It may require a fine blanking setup with a clamp ring as described in earlier posts. The complexity of the die may be reduced if you are willing to do some hand trimming of the deep drawn cover.

    You also need to pay close attention to die lubrication if this is a do it yourself project.

    A favorite lunch time activity years ago was watching aircraft fairings being deep drawn on Zamak punch/die tooling in a 3000 ton capacity triple action hydraulic press. The difference between a ripped part and one that met specification was determined by the location where the operator applied grease to the part with a paint roller.

  12. Likes Repoman liked this post
  13. #28
    Join Date
    Jun 2020
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    104
    Post Thanks / Like
    Likes (Given)
    29
    Likes (Received)
    32

    Default

    Quote Originally Posted by Repoman View Post
    Is Rhino3d applicable for CAD/CAM?

    I've been thinking about taking an online course to CNC that seems pretty thorough, although spending a couple grand without getting hands on experience with machines seems kind of a bad deal (the course does seem really thorough overview of machining in general and focuses on specific machines like Mazak, Haas, some stuff with Fanuc...tool geometry, grinding, required/applicable math, material characteristics, etc).

    I definitely can't afford Solidworks, but I realize I do need to get going on CAD/CAM, I've toyed with the idea of buying a CNC router in the past to learn some CNC basics, but don't know if that's really a great approach either.
    Rhino is applicable for CAD. There are a few CAM programs that you can run inside Rhino, but they're a separate purchase (RhinoCAM, BobCAM for Rhino, and madCAM). If you take the class you should qualify for the student discount and can get Rhino for $140. The only CAM software that I'm aware of with a perpetual license at a discount for students is a Rhino plugin called madCAM, which is $180 for their 5x package. Its lacking in features and is incredibly tedious for anything complex, but its fast for simple parts and a solid introduction to CAM software.

  14. Likes Repoman liked this post

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •