[ciccio]

Can you please tell me more? Did you simply "cut" the needle?
I will test as soon as you answer me !
A commercial "suction nozzle" is about 150 USD !!!!!!
Paolo

[ciccio]

Thank you for the GREAT idea, Alexandre !
I could not wait, so I built the gear with a flattened needle and
an aquarium pump ( preiously used for the PCB bubble etcher )
and a piece of tube: it works great!!
I'm here in front of my pc, answering you with one hand, and with the other
shaking with decision the needle with attached a SMD 1206 resistor:
it stays attached to the needle without problems!
Now I'll find a small 200 step stepper, and I'm thinking the best way to
attach the needle to the stepper, then to the Z axis.
Is a good idea to use a solenoid for Z axis as in LPKF pcb drillers ?
Paolo

[alexg]

Thank you for the GREAT idea, Alexandre !
I could not wait, so I built the gear with a flattened needle and
an aquarium pump ( preiously used for the PCB bubble etcher )
and a piece of tube: it works great!!
I'm here in front of my pc, answering you with one hand, and with the other
shaking with decision the needle with attached a SMD 1206 resistor:
it stays attached to the needle without problems!
Now I'll find a small 200 step stepper, and I'm thinking the best way to
attach the needle to the stepper, then to the Z axis.
Is a good idea to use a solenoid for Z axis as in LPKF pcb drillers ?
Paolo

I cut the needle with a sharp "xacto" blade rollingundefined it back and forth slowly to get it as flat as possible and if necessary I use very fine grit sandpaper to finish it up. www.smallparts.com has some needles already flat. They are nice..

The Z axis motors do not need to have 200 steps at all !!! You do not need much precision for rotation and the up and down movement has much precision added by the driving screw. I am using a small motor that was originally used to position a tape head in a streamer backup unit.. A solenoid on the Z axis would be a bad idea... Even resistors have different heights depending on the value and maker. Capacitors are much worse. We need some precision there.

The attachment of the needle to the rotation head needs something done on a lathe... I can't imagine other way.. The format would be something like this:

-----------------------
| |___
\
\ /-----
\ /
------- -------
\ /
\ /


Bad ascii art.... :-)

If you can get me a easy and cheap way to do the XY movement I can solve most of the other problems ;-)

Best regards,
Alexandre

[ciccio]

After some expensive experiments with CNC, I will use:

FRAME: Flexlink aluminium structural system, does not require milling,is a sort of " Lego" game, just cut and go, with lot of accessories,angle, brackets,fixings, etc.
MOVEMENTS:it has to be lightweight,fast, easy to move,precise, easy to build, inexpensive: 3 or 4 small V-grooved bearings running on 2 shafts, there is an alluminium accessory to fix 2 shafts on Flexlink lateral T slots, they can move with a breath of wind ( try this with 4 linear bearings... )
POSITION CONTROL : no expensive and noisy ballscrews, but easy to install, noiseless,inexpensive Synchropower timing belts with related timing pulleys
( a professional version of movements used in every ink-jet printer)
:::::::::::::::::::::::::::::::::::::::::::::::::: :::::::::::::::::::::::::::
Milling and lathingis are expensive, time consuming and sometimes not very precise; consider the use of some extruded structural aluminium similar to Flexlink, after all you can save money and time and have a very precise machine.
A timing belt is very precise and ( very important for us) allows some small misalignement ( users of leadscrews know what I mean ! )
and no backlash at all. You can see Flexlink also on www.rs-components.com
and there are many similar aluminium systems.

[ciccio]

Do you use a stepper on Z axis ? No problem if feeders and PCB are not very well leveled?
About needle :your plastic tube rotates 360 degrees , or 180 degrees ?
Will you consider the use of an IC as pressure sensor ( to know if something goes wrong, and to gain some speed when picking the SMD component )?
How small are your steppers?
Paolo

[alexg]

Do you use a stepper on Z axis ? No problem if feeders and PCB are not very well leveled?
About needle :your plastic tube rotates 360 degrees , or 180 degrees ?
Will you consider the use of an IC as pressure sensor ( to know if something goes wrong, and to gain some speed when picking the SMD component )?
How small are your steppers?
Paolo

Yes, one stepper for up and down and another one for rotation. The neddle actually rotates 270 degrees. I have not got to the point of actually picking up the components :-( My idea is to have some flexibility on the needle coupling to cope with the small differences in the level of the board and feeders. In the first version I am planning on using just cut pieces of the components tapes. Nothing fancy...

Best regards,
Alexandre

[ciccio]

Just arrived from the famous "my friend with a lathe".
We tryed to drill the axis of a small stepper ( we can !)
to have an axial output for the air-vacuum from the needle
( pratically: the needle is on the axis of the stepper, the axis is drilled,
the tube is connectet to the top of the axis, coaxial to the needle, soory, my
english...). We think to use a small stepper normally used as carriage
driver in ink-jet printers.They are the smallest steppers with bearings I can find. We want to try to use some elicoidal spring to push needle against PCB and feeder ( Z axis), to avoid problems with not-so-leveled PCB and feeders.
Z axis will have gear and pinion, to gain speed.
No idea for the squaring station, but it is not important now, till I use 1206 SMDs.
I hope to find ( for free ) a refrigerator pump, just to see how much void it can create.
SMD pick and place....not so easy, but lot of fun !
Paolo
PS Is there a way to exchange pictures ?

[Shibumi]

We recently purchased a machine for prototype and small production runs. It was a disaster for several reasons: 1. Z-axis and pickup head are poorly designed; 2. Software is lacking in its ability to import feeder settings, and; 3. The custom feeders are inadequate. However, the machine has decent basic features and could be re-worked and made functional. A similar machine could be built from scratch on a budget.
We have put considerable thought into what it would take to make it work well. Too much to take the time to write about. I would prefer to brainstorm over the phone and then post conclusions for everyone's benefit.
It will require some machining, P&P software, and either off the shelf feeders, or holders for short lengths of parts tapes.
I have searched for an open-sourced P&P software application to start with, but have not been successful.
Anyone interested in collaborating on this, please call me.
Frank Will
Shibumi Controls, LLC
954-558-4369

[kreutz]

We recently purchased a machine for prototype and small production runs. It was a disaster for several reasons: 1. Z-axis and pickup head are poorly designed; 2. Software is lacking in its ability to import feeder settings, and; 3. The custom feeders are inadequate. However, the machine has decent basic features and could be re-worked and made functional. A similar machine could be built from scratch on a budget.
We have put considerable thought into what it would take to make it work well. Too much to take the time to write about. I would prefer to brainstorm over the phone and then post conclusions for everyone's benefit.
It will require some machining, P&P software, and either off the shelf feeders, or holders for short lengths of parts tapes.
I have searched for an open-sourced P&P software application to start with, but have not been successful.
Anyone interested in collaborating on this, please call me.
Frank Will
Shibumi Controls, LLC
954-558-4369

Frank, we are (practically) neighbors, I live in Miami. Could you, please, post a couple of photos of your "p&p" machine, feeders, etc?

Best regards,

Kreutz.

[cnczoner]

We recently purchased a machine for prototype and small production runs. It was a disaster for several reasons: 1. Z-axis and pickup head are poorly designed; 2. Software is lacking in its ability to import feeder settings, and; 3. The custom feeders are inadequate. However, the machine has decent basic features and could be re-worked and made functional. A similar machine could be built from scratch on a budget.
We have put considerable thought into what it would take to make it work well. Too much to take the time to write about. I would prefer to brainstorm over the phone and then post conclusions for everyone's benefit.
It will require some machining, P&P software, and either off the shelf feeders, or holders for short lengths of parts tapes.
I have searched for an open-sourced P&P software application to start with, but have not been successful.
Anyone interested in collaborating on this, please call me.
Frank Will
Shibumi Controls, LLC
954-558-4369

Frank,

I've been lurking in this thread because I've been interested in doing this too, being tossed up between purchasing a system or modifying a manual one to CNC, or making one mostly from scratch. I'm very interested in collaborating on this, and I'm in Palm Beach (Wellington), BTW. For the next 2 weeks, I'm swamped beyond all recognition with a robotics competition, but I'll call you when I get a chance and chat for a few.

Cheers,
-Neil.

[Eclipze]

I've been working on my design lately. It's all in CAD, however getting quite detailed and quite happy with the design. Getting close to finishing the design. I've reached the stage in CNC machining skills that I'm more than confident about machining the parts to make it. I'm quite happy with creating the electronics and embedded code to run the local functions, however the PC software is the component which is the difficult part. I'm not sure how to tackle this one.

I have been thinking of setting up a local micro to control the stepper and peripherals and run self standing, after being downloaded an instruction set. Then having a PC program to convert the pick and place data into suitable format to download to the machine. It's a lot of work and loses some flexibility, so would prefer to use a better PC program if one can be found.

[Shibumi]

1. We have a lot of clever ideas for the pickup head and auto sensing.
2. Stepper motor controllers are inexpensive. Don't bother designing your own.
Frank Will
954-558-4369