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design cutting moulds (by step)

depends on how bulky the vent is but we are about 100 to 300 mm. but I ask myself: But what manual do you have in the office that there is nothing written? It is also true that some things are also of logical deduction.... since we first explained to you where the rubble comes from.... it becomes trivial to ask how much I have to raise the bottom mold. Do you have a spriz so much carbide better?
 
turn the page.... top right... If you miss the pages lick your finger before turning them? ?
 
from my deduction the effort for cutting the piece should be at the end of the mold, when the useful piece is detached. Is that it?
 
there will certainly be some effort at the end of the mold, where you break the piece from the strip, but it can not be all concentrated there. would mean you have a step mold making the piece in one step, so the mold is centered around the piece, and you are centered on the press, etc.
efforts are necessarily distributed along the strip, if you need more steps to get the desired shape, and for that there must be a chapter that shows you how to take into account the pulling efforts etc.
Greetings, reborn.

p.s. certain vents go out also on the side, +o- horizontally, if you use cams... I ask vein.. .
 
Matricola_Gigi said:
from my deduction the effort for cutting the piece should be at the end of the mold, when the useful piece is detached. Is that it?
Click to expand...
but also not. if in the first step punches 20 holes diameter 10 efforts more than at the next or final step that cuts the strip of broad sheet 20 mm. each phase should be studied to determine the corresponding effort. However, it would be good that I first learned how to make molds in a single pass to study how to size. Facts of excel sheets to facilitate the way to calculate
 
Okay, okay. However, keep in mind that I'm trying to figure out the basic haircut, which is expelled from the bottom, not on the side. in some other post some of you spoke of thermal expansion. Tell me more?
 
the rubbing of the punches in the matrix causes heat that not disposed of due to thermal expansion of the components and therefore change of tolerances. to this are added the effects of bending due to mechanical efforts.
 
Calm down....the rubbing is between punches and sheet, and between matrix and rubble. then there is a bit of friction between punches and guide (I referred to that) and from what I understood also the springs of the Premierlamiera would tend to develop some heat. Moreover there is the sliding of the columns compared to the compasses, and the various measures to accompany the tape during the change of "phase", that is from one step to another. in practice all that in the mold proposes relative motion, good or bad will have to develop heat for friction. the two main members are the first two reported and usually easily manageable, p.e. with emulsified water.
others or are negligible, or you neglect them the same, otherwise you lose yourself in a purely academic dedalo. at the bottom of the mold and metallic and stirs the air around it....
 
Yes, I understand, but for thermal expansion you have to act on the size of the punches?
 
In theory, you have to keep against it especially if you have to make holes in tight tolerance. the important thing that is usually done is to use normal tolerances and to calculate how much emulsible oil to use to dispose of heat without geometric changes
 
Okay. Let's talk about breaking strength. some manuals measure it in newton and others in dan (decanewton I suppose). How do you measure it? Perhaps the dan is useful because from here the cutting force comes directly?
 
I personally use the units of the international system therefore the breaking load of the material in mpa i.e. in n/mmq the force in n or kn when it is high then pass to the tons when it comes to forces and press. the dan is the kg and it is used precisely because in the years it has passed from the practical system to that yes. eventually use whatever you want. The important thing is that you do the conversion formulas right.

how do you measure it? actually could be in the bar if I know hydraulic cylinders
 
since the cylinder area computes in cm2 and since the bars are kg/cm2 .... you have the constant of the press and therefore you know the strength in kg. then you can use the units you best believe. I do as mixed as you see, depending on what I'm comfortable to find.

as I said if you use an excel sheet you can do all the accounts as you want and get everything you need.
 
meccanicamg said:
since the cylinder area computes in cm2 and since the bars are kg/cm2 .... you have the constant of the press and therefore you know the strength in kg. then you can use the units you best believe. I do as mixed as you see, depending on what I'm comfortable to find.

as I said if you use an excel sheet you can do all the accounts as you want and get everything you need.
Click to expand...
I think that to listen to this coming next year.someone thinks that the whole thing is pink and flowers. Tomorrow then if it was as simple as he thinks matrimony gigi all to make molds and money.
 
whatever you learn piece by piece... slowly.. .
Can you please tell me if there's a fixed number of centrists to place and the "cardine" points in which to place them?
 
Matricola_Gigi said:
whatever you learn piece by piece... slowly.. .
Can you please tell me if there's a fixed number of centrists to place and the "cardine" points in which to place them?
Click to expand...
hi, a fixed number cannot be there, given the variety of possible templates obtained from mold.
you could say that the more you can put it better is for the accuracy of the step. In fact, beyond the number that tells you common sense, you don't have to go.
For example, if you're working a piece that, "d' imgombro" is a record, and you're only getting one at a time, you're left with all the sheet between 2 later disks (a kind of double triangle) to exploit. there you are forged because you can place the centerpieces with the interasse major and the ø major (all with criterion) and are on the discard, and you only need 2 per step.
If the piece does not leave sufficient or unsuitable waste areas, you must consider/make enough holes or templates of the piece. If there is nothing of all this, we should, e.g., widen the strip or still work a little fancy.
and remember the centerpieces have to be polished at the tip of a few 1/100, compared to the hole they have to center, if not even 1/10 poorer, if they are not doing you do absurd things. or previewed already 1/10 scarce for all length. commercial punches are "calant" and the cut holes rather tighten once freed. . .
Moreover the more the strip weighs and/or is unreliable the advancement of the press, the more you need big to pull the sheet in place.
Good luck, reborn.
 
Thank you for the reborn answer.
So there's not even a law that tells me how big the centerpiece is? I don't know, the weight of the strip, the width or thickness of the strip.. .
 

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