Downing's Manual Pick & Place Machine

[Downing]

Hey guys!

I know I've been quiet for quite some time but I've be buried in real life and case commissions as well as my own projects that finding the time to actually post has been difficult! But enough of that. I've got a few projects going on now that I've been slowly making progress on, but one of these projects has required me to do a lot of SMT component soldering.

To those who don't know, SMT stands for "Surface Mount" components and can get super small and require a whole new look upon soldering in general. This in turn has led me to think that if the progress of my project continue, I'll need to have some form of SMT support.

I saw this last year on Hack-A-Day and was quite impressed with its simplicity and accuracy. Though I had no use for one at the time it kind of got filed away and forgotten. But, then came this project and it really made me realize how important a steady hand is, which I'm finding I'm not as much as needed.

So this little aide, should I get it working correctly, will really allow me to take the headaches of using tweezers and hope to a more stable level without breaking the bank. He says this can be made up for less than $100. We'll see if he's right, but for now here's what I have drawn up.









All in all I'm liking how this looks in 3D and hope I can make it translate into real life. We'll see soon enough I'm sure and I'll have more updates on the project that's been taking up all my free time in the next few weeks.

 

[Hermaphroditus]

Seems pretty neat. Do you already have a reflow oven as well, or will you be making one with that?

 

[Downing]

It's on the list of things to do, but I right now the components that I'm using don't get any smaller than 0603 so I can use my re-work station for the time being. I do eventually want to either get one or make one, but for now I can skate by with what I've got.

 

[βeta]

I think that if your bearings were riding on round rod instead of angles, they would be more accurate. You only have an illusion of a full line of contact between each bearing and its surface. You will really only have a single point of contact, because the angle won't be perfectly flat or parallel. You won't know where that point of contact is, which will cause little shifts in movement. If you ride on round rod, you will definitely only have one point of contact per bearing, but you know it isn't going anywhere.

 

[robm]

Beta's right, one thing I learned from my CNC build is that the angle bearing approach is just terrible in terms of stability. I'm in the process of redoing my whole machine using rods, it's going to be soo much better.

 

[laingsoft]

Our of curiosity, why do CNC builders use the angle-bearing and rod-bearing things rather than just C-tracks? If they are made accurately enough, they should offer the same accuracy, no?

 

[Downing]

I would guess the issue is that the you'd have to have the bearing in so tight to stop the lateral movement that it would probably get pinched and not slide properly.

As for using the angle instead of the rod, I just looked at the guys video and everything seemed to move very smoothly and fluidly. If I were planning on using stepper motors and a controller, than yeah I'd probably use the rod, but this is where manual has an advantage over machine in that we can compensate on the fly for things that may be slightly out of line.

I shouldn't have a problem keeping things parallel enough that it will cause me any issues I can't over come.