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View Full Version : RFQ: small, primitive Press with cutting and bending capability



Noel.C
25-05-2012, 07:50 PM
60516052

Hi folks.

I registered here in the hope that I could hire
someone to do a job for me. I am working on a hobby
project that requires a set of custom tools. I have
had a bitter hard time trying to get it made through
big companies with no luck in 3 weeks.

The project consists of

1: A small simple press
2: Male and Female cutting die
3: A Punching Device
4: A bending device


I am not an engineer, but I have at least put together
some 3d models and outlines of what I am trying to
achieve, but it would require the knowledge of an
engineer to turn it into a usable device
-------------------------------

What I want is a press that you could put 1mm aluminium sheet into
and when struck with a hammer, drives a cutting die through the sheet
to leave a nice clean cut out. The press then returns to its default position
and the cutout can be safely removed. See attached the press I had in mind
and also an outline of the cutting dies I need.

What I also wanted was the ability to swap out the dies for a tool that
allows the cut out to recieve 2 hole punches. After which the punch tool
can be swapped out for a bending tool that allows the cutout to recieve
an exact bend.

All of this for an item around 25x35mm in size.
I hope that made sense. I am looking for someone to make it real for me and
I have funds available now to get it started.
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John S
25-05-2012, 09:29 PM
From what I can see this can all be done with one set of punches on a simple fly press, google fly press.

If the male and female have the bend shape in your last picture, bottom right but also the outline shape of the part the flypress with first cut it, then bend it and a set of spring loaded pins will finally punch the holes.
Ejection springs are needed to obviously eject the part ready for the next item.

Noel.C
25-05-2012, 09:39 PM
Right ok, thanks John. I see what your saying, if I maybe redesigned the
cutting die so that it cuts, punches the holes and bends the shape at
the same time. Good plan. Fly presses look awfully expensive, well outside
my budget, I was hoping to accomplish all this by banging on a mild steel
plate to create the force necessary for the cutting and punching etc.

I am a chainmail armour crafter. I like to keep it simple and bang on
things with a hammer to get a result.

I was not sure if I could generate enough force to cut out the shape
and do the punches at the same time, which is why I seperated them
into individual processes.

Noel.C
25-05-2012, 10:06 PM
So when I say primitive, I really mean it. Think of me, in a dirty garage, with
a dirty old mallet and a dirty old anvil banging away like a caveman.

This press needs to be stupidly simple that even a headcase like me could use it :D
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Web Goblin
26-05-2012, 09:06 AM
I think a Fly press would be the way to go as well for this. I think you would get a better more even cut with a fly press. If you hit the cutting jig off centre with a large percussion adjuster you are likely to knacker it.

Noel.C
26-05-2012, 11:19 AM
Ok cheers

I get what your saying, if it is not positioned correctly and I thump it, expensive things
are gonna get destroyed. Considering that I would like to make about 800 of these cutouts
I would agree that the probability of that happening is very high.

Cheapest second hand fly press I can get locally is about 250, no point buying them
online because any cheap ones include freight charges and new ones cost up to 5 grand.

All a bit expensive for my taste.

Is there any way of getting a small arbour press like for example a Clark AB500B 1/2 Ton
to do this job? That way I can pay 32 for that, along with the lazer cutting costs for the
die?

Web Goblin
26-05-2012, 12:32 PM
An arbour press might do the job. Another option would be a small bottle jack fitted into a custom made steel box section frame.

Jonathan
26-05-2012, 12:53 PM
Is there any way of getting a small arbour press like for example a Clark AB500B 1/2 Ton
to do this job? That way I can pay 32 for that, along with the lazer cutting costs for the
die?

Wouldn't that type of press be a bit slow, especially with 800 to make? Also surely the die would be CNC milled, not laser cut.

Noel.C
26-05-2012, 01:02 PM
Granted the bottle jack idea is certainly cheaper, but I think the
Arbor press will be more helpfull in the long run. It might help a bit
with riveting chainmail rings and putting belts together etc.

So

What I need here, is a cutting die that also provides a bend
and a punching action too and which fits into an Arbor Press.
Think I'll buy the press first and as im waiting for it to arrive.
I'll spend some time figuring out a design, then I'll come back
here and see if someone is willing to make it for me.

Thanks for the help, really feel im moving in a better direction now.

Hi Jonathan. Slow is not an issue for me really. It takes me
about 4 or 5 months putting together a full chainmail armour set.
Time is something I have plenty off. As for the die, yes CNC milled
sorry about that!

JAZZCNC
26-05-2012, 01:42 PM
The percusuion adjustment tool could be made to work if you struck a solid shaft within a hollow shaft with Die attached so not movement occured. Bit like a fly press but with out the screw.? . . .But why would you when fly press is ideal tool made for the job at 250 and would last for ever.
Even if you DIY the materials alone due to the strength required would be getting up that way.? . . Go for the flypress is my suggestion.

Think the cheap Arbour press would die quickly in a production enviroment but could be worth a shot at 35.!! But like say it don't take long to reach 250 and waste money when things don't work has expected and the fly press will always be worth 250. . Go for the flypress is my suggestion.

Noel.C
26-05-2012, 02:02 PM
I know it is only 250 but as of late I have spent close to 2g on
hobby related bits n bobs. Soon though, I'll want to sell off a few
things so I'll get the fly press eventually, then I'll relegate the
Arbour press to minor duties instead :-)

m_c
27-05-2012, 01:57 AM
An arbour press would be my choice, however I'd also be checking the required cutting/shearing forces first to make sure I got a big enough one.

Although as John S has said, building a one shot press will be more efficient in the long run, it may be easier to do it in multistages, in terms of constructing the dies.
The dies could be laser cut, however they'd still need finished to tolerance by milling/grinding/polishing, with the cutting edges hardened, tempered then ground to create a durable edge.

Noel.C
27-05-2012, 02:32 AM
Hi m_c

I will be working with strips of 1mm aluminium so I dont think im gonna need major force applied
to get a cut out. Surely 1/2 tonne force would do that providing that the dies were of decent
quality.

I do prefer the idea of having seperate dies for the job. Technically, I could put together a
DXF file of a die that would do all three and maybe I will! when I get
the fly press later on. For the mean time though, 3 reasonably durable dies in
tool steel or something similiar will do the job just fine.

My only current concern is how much those dies will cost me, but I'll worry about that at a later time

Ricardoco
27-05-2012, 03:01 AM
Hi m_c

I will be working with strips of 1mm aluminium so I dont think im gonna need major force applied
to get a cut out. Surely 1/2 tonne force would do that providing that the dies were of decent
quality.

I do prefer the idea of having seperate dies for the job. Technically, I could put together a
DXF file of a die that would do all three and maybe I will! when I get
the fly press later on. For the mean time though, 3 reasonably durable dies in
tool steel or something similiar will do the job just fine.

My only current concern is how much those dies will cost me, but I'll worry about that at a later time

Looking at your designs it occured to me that the male side of the cutting die could be concave across 1 axis thus allowing it to begin cutting at both end and finishing in the middle thus lowering the cutting force required even further as opposed to bashing through the whole cut at once...if you know what i mean.. lol

Noel.C
27-05-2012, 11:26 AM
Looking at your designs it occured to me that the male side of the cutting die could be concave across 1 axis thus allowing it to begin cutting at both end and finishing in the middle thus lowering the cutting force required even further as opposed to bashing through the whole cut at once...if you know what i mean.. lol


Hi ricardoco

I think I understand what you are getting at, only had 3 or 4 minutes there to
try it out in 3d as about to dart of to work here.

6068

So basically, rather then cutting through the entire surface area at once, you
want the force to be focused on a smaller surface area?

Sounds good and if it decreases the strain on the arbor press it might be worth doing.

Cheers
Noel

Noel.C
30-05-2012, 12:37 AM
6086

Could anyone give me a rough guestimate as to the probable cost of these male/female
die sets?

They are meant for 1/2 tonne arbour press, measurements wont be right yet because press has not arrived but basically they will be around the 30x30mm except for the female backing plates. I suppose the backing plates could be mild steel and the diestool steel or similiar.

The cut and stamping set would need to have tempered edges.