PDA

View Full Version : Best way to cut .010" Blue Spring steel?



gary350
08-17-2011, 03:57 PM
I had a few places try and laser cut these but the laser is too hot, speed is too slow or something it melts the edges.

I had someone try and water jet cut these it blows the metal off the table. One guy tried gluing the metal to sheetrock it cuts fine but then how do I remove the parts glued to a piece of sheet rock.

I need someone to cut me these 100 or more each time. Last time I had 120 cut 14 were bad. Enough metal to cut 60 or these parts is $30 from WW Grainger. These sell for $3.00 each.

I can cut these out myself by hand assemble line style doing 60 parts at a time it takes me 5 minutes per part. I only hand make these for myself. If I could buy some at a good price I could sell them.

http://i43.photobucket.com/albums/e358/gary350/ReedValve.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-005.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-006.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-007.jpg

http://i43.photobucket.com/albums/e358/gary350/DJ-RV.jpg

DFMiller
08-17-2011, 04:14 PM
Gary,
Have you thought of chemically etching them?
Or get or make a Punch and Die?
Dave

Toolguy
08-17-2011, 04:16 PM
I would build a compound die to do those. A compound die blanks and pierces everything in one hit so you would have a part each time the die closes and opens. You could run off hundreds of perfect parts in an hour. You could have the punch and die wire EDMed out of one piece of hardened tool steel and use a round punch for the center hole.

macona
08-17-2011, 04:18 PM
You need to find a better laser shop. I have seen stuff this small and light done all the time.

Use something along the lines of hot glue to hold the parts down and then use a heat gun to pop them off.

Or find someone with a wire edm. That will give you the best finish.

Evan
08-17-2011, 04:23 PM
It should work fine on a waterjet if you make a subtable with correctly placed supermagnets to hold the parts.

Black_Moons
08-17-2011, 05:13 PM
I was thinking super magnets too.

Alternatively, superglue will release once heated up to a reasonable temp (Im pertty sure its still lower then would affect the temper)

So will verious loctite products. waxes. Hot glues. etc.
Hot glue can be cleaned off pertty well and easily.

Punch and die really sounds the best IMO though if you plan to make a lot and sell them. At worse they might need the lightest deburing afterwards, But im thinking with your application you might be able to just tell them to put the burr side up and they would'nt cause any problems.

PS: VERY nice work on the finished ones.

gary350
08-17-2011, 05:30 PM
A punch press die would be excellent. I thought about that myself. I have 2 blank die shoes. I sold both of my 5 ton OBI mechanical punch presses. I have 3 punch press dies for parts I don't make anymore and no punch press.

I did chemically etch some of these parts. It takes time to get it ready to etch then about 1 hour to etch them. Parts do not come out with a perfect smooth edge they all have to be belt sanded to remove the uneven etch. Some places the metal etched too much some places not enough.

brian Rupnow
08-17-2011, 05:45 PM
What the heck are they???

adatesman
08-17-2011, 06:01 PM
Valves for a pulsejet?

form_change
08-17-2011, 06:04 PM
Make up a sandwich of two thicker parts with a whole bunch of shim layers (30 or 40?) between then use wire EDM to cut. Bolt the two thicker bits of material together to get a tight pack. We have done it before for some special solder tags.

Michael

MaxxLagg
08-17-2011, 06:07 PM
We make all kinds of things out of blue clock at work. I have a die that will take the 4 and 6 inch wide stock we get and shear it to a suitable length. Then we stack the pieces up, weld them together along the edges with a few quick beads and then send them in the the wire room to wire EDM. If you're not opposed to farming the work out this is the way to go.

Jpfalt
08-18-2011, 02:58 PM
Your best bet is to pop the .250 hole in the center, stack them up on a bolt into a block shape and wire edm the profile with 2 or 3 narrow connections left to the outer block. Then remove the bolt, unstack and do a final cutoff with either a 1/32 abrasive cutoff or a nipper, whichever leaves an acceptable edge profile. The EDM will leave a clean edge that will not need further processing.

Tony
08-18-2011, 04:11 PM
for what its worth I second the "find a new laser guy" notion.

it should be a cake walk.

Zahnrad Kopf
08-18-2011, 04:16 PM
We wire the stuff all the time.

J Tiers
08-18-2011, 08:54 PM
Valves for a pulsejet?


Betcha......

That "head" in the one pic is very telling......

EddyCurr
08-18-2011, 09:29 PM
A punch press die would be excellent. I thought about that myself. I have
2 blank die shoes. I sold both of my 5 ton OBI mechanical punch presses.A rough estimate of the lineal distance represented by those ten petals
within a 2.162" dia circle, plus the ID hole comes to well over 20".

Perhaps a tool and die maker can comment on the amount of tonnage
required to stamp such a part in one hit. My vote is that a 5T OBI
press isn't going to begin to make a dent in the material.

.

deltaenterprizes
08-18-2011, 09:36 PM
They are daisies to go on VWs like in the 60s & 70s!

J Tiers
08-18-2011, 11:33 PM
A rough estimate of the lineal distance represented by those ten petals
within a 2.162" dia circle, plus the ID hole comes to well over 20".

Perhaps a tool and die maker can comment on the amount of tonnage
required to stamp such a part in one hit. My vote is that a 5T OBI
press isn't going to begin to make a dent in the material.

.

If made with shear, it might work...... I'd want to look it up. I've made a couple punch/die sets and shear really helped them. They were Greenlee style.

Cheeseking
08-19-2011, 12:07 AM
A rough estimate of the lineal distance represented by those ten petals
within a 2.162" dia circle, plus the ID hole comes to well over 20".

Perhaps a tool and die maker can comment on the amount of tonnage
required to stamp such a part in one hit. My vote is that a 5T OBI
press isn't going to begin to make a dent in the material.

.

Yeah. No way 5T is gonna do it unless your die profile cuts just the acute slot and 1/2 the radii left and right. Then index on a .25 pin to do the rest of the petals one hit at a time. The jet guy you used should be able to do it. We water jet thin stuff all the time. I put down a sheet the blue or pink polyisocyanurate foam underneath and plop a sheet of sacrificial crs or galvanized on top to keep it flat. Then some heavier bars around the edges to keep things in place. Tabs if you had to. I would also stack 4-5 layers of the shim stock and cut it at the same time. The laser guy should have been able to do that no problem either. EDM is a ridiculously expensive way to go but it would work too. Problem with any method here seems to be the low qty and lack of $$ involved.

Weston Bye
08-19-2011, 06:58 AM
As others have said, wire EDM a stack of them.

After seeing some of the work Ben Flemming demonstrated, I think even a plunger EDM with a complex electrode could do it, although slower. for less work on the electrode, do just one petal at a time and index the part. Again slow, and the petals might exhibit some non-uniformity from the first petal to the last due to electrode wear.

Unless you want to get into EDM yourself, you would probably have the best result farming these out for wire EDM.

planeman
08-19-2011, 08:53 AM
These are obviously flapper valves for a Dynajet, a model airplane pulse jet engine of the 1940s and 1950s. I had one of these back in the 1950s. They are the loudest things man ever created!

Planeman

EddyCurr
08-19-2011, 02:21 PM
I had a few places try and laser cut these but the laser is
too hot, speed is too slow or something it melts the edges.

I had someone try and water jet cut these it blows the metal off the table.
One guy tried gluing the metal to sheetrock it cuts fine but then how do I
remove the parts glued to a piece of sheet rock.As said by others, a further search for laser shops with the control to cut
this material should be fruitful.

As for restraining the material during water jet cutting, I presume that the
whole sheet is being blown about. What about a 'stretcher frame', a sheet
of heavier material with an opening in the center? The 0.010 material could
be secured in the opening with perimeter clamps or fasteners. All the clamps
would need to be are lengths of 1" flat bar drilled and attached along the
ID opening of the stretcher frame - insert one or more pcs of material to
be cut, tighten the clamps and initiate the cut process.

Whether laser or water cut, consider designing the parts with tabs/lugs so
so they remain attached to the sheet. Then detach them in a secondary
blanking operation. Lugs small enough to retain the parts to the sheet
should be easy to shear in a single simple hand-powered operation of a
punch with a suitable OD and a locating button that centers on the part's
axis hole. Perhaps the punch could be driven by an air chisel tool.

Depending on the quality of the blanking operation, the lugs may/may not
require a third operation on a belt sander or grinder to dress any burrs.

.

EddyCurr
08-21-2011, 02:00 PM
One guy tried gluing the metal to sheetrock. It cuts fine but then how do I
remove the parts glued to a piece of sheet rock.Instead of applying glue to the entire sheet, deposit it selectively in regions
of the sheet that will be scrapped after cutting.

One approach for this might be to re-nest the parts in a manner that leaves
'islands' across the sheet which are intended for receiving glue. A simpler
method may be just to accept that a small number of daisies will be lost, stuck
to the sheetrock - perhaps a fair trade for eliminating the secondary operations
apparent with my previous suggestion.

.

Paul Alciatore
08-21-2011, 02:55 PM
If made with shear, it might work...... I'd want to look it up. I've made a couple punch/die sets and shear really helped them. They were Greenlee style.

J, I have had a lot of experience with Greenlee punches and the shear factor is their secret. But the piece they remove from the metal is anything but flat. They are often so twisted that they must be un-screwed from the bolt used to close the dies.

Perhaps the shear angles could be applied to the outer piece of the die, but then the stock sheet would become very twisted so you would have to cut individual blanks for each part. And the ten petals would be a factor. I mean, how many initial points of contact would the dies have. Each such point produces TWO shearing points that travel from the initial point. With ten petals you could have 20 shearing points. Each shearing point adds additional tonnage to the required size of the press and at that point you may as well have not used shear at all. You could use the more modern style that Greenlee uses in their punches today. By having only one direction of cutting from the initial point of contact, they reduce the force needed to close the dies and also break the knockout into two or more pieces. This idea could be applied to a die set that applies the shear to the outer or waste portion of the stock, but you would still have a lot of shearing points if you use a point per leaf. Perhaps two points could be made to shear their way around the entire part, or perhaps four. Sounds like one heck of a grind job for making the dies. And you would probably need a clamping ring in the die set, around the central hole, to hold the part in place while all this shearing action is taking place. It would need a heavy spring to clamp it tightly. This clamping ring could have the actual petal shape of the finished part to better control any distortion of the petals as they are being cut.

Even with all this, my gut, along with some experimental work with Greenlee style punches, tells me that a 5 ton press would be marginal. Perhaps you could make it work, perhaps not. After all, spring steel is a lot harder to cut than the aluminum or mild steel that Greenlee style punches are designed to cut. The real secret in the Greenlee punches is the screw: they are way better than grade 8. The 1/4" Greenlee screws in their older punches are very difficult to replace and the 3/8" ones are just barely replacable with a grade 8 screw.

I am not a die maker so the above may not conform to standard die terminology but I hope it can be understood.

gary350
08-21-2011, 06:46 PM
I have a punch press die that I built it punched .040" spring steel parts very easy with a 5 ton punch press. The parts have a cutting area about half the size of these .010" parts. Also the design of the die makes a big difference in how many tons are required. A flat end punch that punches the whole part all at one time takes 10 times more power compaired to a punch that starts at the center and shears the scrap off towards the outside edge. It only needs a shear angle of about 3 degrees to make .010" steel punch easy. I still have my punch press die design book from college it is fairly easy math.

J Tiers
08-21-2011, 11:09 PM
The nice thing is the fact that these are so symmetrical... any tendency to "walk" in the die is balanced, distorting forces are balanced, cuts are mostly radial, or nearly so, there's a lot to like about it from the standpoint of using shear.

Shear doesn't HAVE to distort the part or the stock, a greenlee is merely an example of the way shear fixes problems..... cutting a 3" diameter hole in 10 ga steel with a wrench-driven screw....... you require shear.

The issue is possibly the end of the petal, where the shear meets.

No I don't KNOW it can be done, I *suspect* it can, but if it really takes 10 tons, I wouldn't be surprised. For sure it would take a bunch if it was done square. And it might need to be for some reason of flatness, etc.

Of course, one COULD punch it annealed, flatten it to spec, and then heat treat..... that would make a great deal of sense when it needs to be flat.

blue temper steel is not THAT hard, it will take a set, bend, form a nice burr, etc.

beanbag
08-22-2011, 01:38 AM
I had someone try and water jet cut these it blows the metal off the table.

Hold the metal down at the edges, duh.