Magnifying Lamp for Soldering

[rich]

How do magnifying lamps stack up against reading glasses, optivisors and the dental loupe glasses found on ebay for soldering and small batches of SMD placement?  And is the next step up from here going to be a Mantis? (I got the sense from the microscope thread that a scope might be better for SMD inspection, but not necessarily for SMD assembly)

Some context - The headband-visor magnifier I currently use puts my face so close to the work that it leads to neck strain and fume inhalation. I'm not sure what mag strength it is, but it only has a single sheet of acrylic to form 1 lens per eye.

Example dental loupe glasses I was looking at: 3.5X 420mm working distance  http://www.ebay.co.uk/itm/271920086804
and 4X 420mm  http://www.ebay.co.uk/itm/191255887110

[Docholiday]

I too are looking for another magnification device and there ate a lot of choices. But just like anything else it comes down to what you can afford and what works for you. My friend swears that the only tool for her has to be a 100x microscope while another is happy with just high magnification glasses as mentioned already in this thread. For me I have a microscope with 20x magnification which is plenty even doing smd work and IC work too. Also, I have an eye loupe at 20x. Now I am looking for one of those magnifying lamps with dimable leds. Why all these? Well each have their own merits and own specific uses.

For a quick inspection I will pull out the glasses. At other times it may be the eye loupe or the microscope. It just all depends on the situation and my skills and experience that dictates what and when of what I need.

From all of this I have learned two things. One, you get what you pay for and two, what one person may praise and recommend as the optimal and only solution at times may not work for you at all. What I do is simple, I contact the manufacture and find out what the next trade show they will be at and where I can go and touch and feel their solutions. Before I go I make a habit of bringing of what I am working or testing with.

Then why do I use these forums? To get a better understanding of what I need and why. Perhaps a totally different solution. Get valuable insights and opinions, most importantly look for the opinions of those few members like myself that see and appreciate the value of the top end brands. Although expensive! But worth every penny in the long run.

So, for today I learned that the top tears of what I am looking for are Luxor and Aven. The Mantis is nice but an overkill for what I need.

[KL27x]

^ So true.

Some context - The headband-visor magnifier I currently use puts my face so close to the work that it leads to neck strain and fume inhalation. I'm not sure what mag strength it is, but it only has a single sheet of acrylic to form 1 lens per eye.

The mag lamp takes care of that problem and trades it for another. The lamp is so close to the work that you will inadvertently bump it, making it sway back and forth. This is such a big problem for me, I am often putting my chin on the handle of the lamp while soldering, to stabilize it.... which puts me right back at your original problem of neck bent and face close to the work. At least the lamp blocks flux fumes.

(I got the sense from the microscope thread that a scope might be better for SMD inspection, but not necessarily for SMD assembly)

Compared to what? A VIDEO microscope is often described this way, as compared to a stereomicroscope.

[rich]

Ah, I may have incorrectly parsed the microscope thread and missed that subtlety. My take-away was that a magnifier would probably be the right ergonomic choice for manual pick and place with 0402 components, whereas a stereo microscope probably less appropriate due to typically larger magnification/smaller field of view.

[KL27x]

Well, that's true, too. Sometimes you will want to use a mag lamp for placing components on a pasted board, because you will have a wider view. Generally, you will use the least amount of magnification as necessary. Looking thru a microscope on a larger board, you may end up inadvertently smudging your paste more often.

Personally, I think solder paste is quite often more trouble than it's worth in absence of a pick n place machine to finish the job. Part of the problem that I encounter is that it is quite impossible for me (so far) to pick up small SMD parts in a consistent orientation with a pickup tool. They quite often take a turn as they get picked up, or get picked up on a corner/edge, which makes adequately accurate/efficient placement a bit cumbersome by hand.

But if that's what you're after, then a mag lamp may serve you better than a microscope. It would be a lot cheaper, too.

[LabSpokane]

Save your cash and get a decent microscope. I started with a magnifier and now all I use it for is task lighting. The cost of a decent magnifier lamp with good glass is already in the Amscope / Microscope.com price range. The cheap magnifying lamps are so flimsy as to not be worth bothering with.

[nctnico]

The problem with a microscope is that they often magnify too much (around 6x is ideal) and need an exact position to sit behind it. With a magnifier lamp you can just hold a PCB under it and look at it with 2 eyes while covering a large area. In many cases you don't need that much magnification.

[LabSpokane]

The problem with a microscope is that they often magnify too much (around 6x is ideal) and need an exact position to sit behind it. With a magnifier lamp you can just hold a PCB under it and look at it with 2 eyes while covering a large area. In many cases you don't need that much magnification.

Not if you get a scope on a boom stand. And the magnification issue is resolved easily with a 0.5X or 0.6X Barlow.

Magnifiers are great for non precision inspection. For something to actually work under for extended periods, there is no comparison with a good scope. Just relating my experience. I have both instruments at my disposal and both are good quality. The scope on the boom stand is what gets used.

[KL27x]

I use my microscope quite a lot. But I still use the mag lamp for several tasks in PCB assembly. (I have a .5 barlow and a boom stand). I still use a lighted loupe for certain things. IMO, there's no need to limit yourself to one or the other. I'd suggest anyone doing pcb work could probably use both.

Even with the 0.5x Barlow, my scope has a FOV of only 2.9 inches. My mag lamp has a FOV over 1 foot.

[plazma]

IMHO a magnifying lamp is good for some inspection cases but not for soldering. And for inspection I just use a good light and go for the microscope for closer inspection.
I solder without any magnification or go to my microscopes lowest setting at 5x and increase if necessary.
5x:

25x:

Sometimes you really need the 25x magnification:

[rich]

I use my microscope quite a lot. But I still use the mag lamp for several tasks in PCB assembly. (I have a .5 barlow and a boom stand). I still use a lighted loupe for certain things. IMO, there's no need to limit yourself to one or the other. I'd suggest anyone doing pcb work could probably use both.

I think that's probably the reality - both are useful.  plazma's great images show where a microscope comes into its own. I think though that I'm going to try a magnifier for manual pick and place because repeatedly switching from 'picking' with plain eyesight to 'placing' through microscope eyepieces doesn't sound comfortable for the neck or the eyes over many hours. I still dream of a pick and place machine and a mantis/lynx but other kit must take priority for now.

[KL27x]

^ In many cases, I have found it much easier and faster to ditch the paste stencil and to solder with an iron.

1. Flux the pads for any number of components you want to do. You don't have to do the whole board at once. On a larger board, you can work on just a couple square inches at a time, to avoid smudging. If doing a lot of boards, you can even do just one or two component values at a time, for ease of parts manangement/identification. If doing a lot of board, you can batch this process and do as many boards at a time as you want, as long as you place the parts before the flux dries out.
2. With the naked eye, use your pickup tool to roughly place the components. No magnification necessary. Just get them in the vicinity of the pads, at least. Repeat for as many boards as you fluxed.
3. Use a tip that holds a good blob of solder; I prefer a large CF tip. Preload the tip with solder.
4. Under magnification, hold/align the part with tweezers. As soon as the part is lined up, touch the fluxed pad or multiple pads with the iron to "paint" on the solder. 
5. Use the part you just soldered as a handle. Holding it with the tweezers, you can precisely move the board to center the next part in the FOV. You maintain a really good connection/continuity between your hands, tweezers, iron, eyes, and board, this way, and this step flies by just like the previous two.

The "placing" in this case isn't a precision operation. The alignment/soldering happen concurrently, and you can use as much magnification as you want without any issue of FOV or looking away to pick up the next part. All your parts of immediate interest are already on the board. This is extremely important to maintain your context. Once you enter the "world of small," you want to maintain that as long as you can. Switching back and forth to the scope takes a little time and mental stress. The only problem is you have to pick up some more solder occasionally. With a large CF tip, you can solder perhaps over a dozen passives before reloading.

I save IC's for last. In a large batch process, using a CF tip, I usually don't even need to stop for more solder on most chips. I can generally pick up enough for drag soldering from the decoupling caps.

[rich]

If I'm lashing something together on protoboard then I'll hand solder it using a similar technique to yours, everything else gets reflowed. Stencils for small batches, pneumatic paste dispenser for one-offs.

[KL27x]

On protoboard, this technique is not as effective. You need to use a smaller tip/solder reservoir, at least, because there is no soldermask. And usually, I am making/designing a protoboard circuit as I go, so setting up multiple components and knocking them out under a scope isn't going to happen.

I actually find this method to be especially efficient in larger batches of production boards, in particular. I've done thousands of pcb's this way, saving my clients a ton of money on assembly of IC-intense pcb's, even after paying myself a decent hourly on the labor - good enough where I am not complaining for the time. After setting aside the stencil and doing it the easy way.

I am getting into a large batch of pcb's that were assembled by a professional at a professional price. And I'm running into 200x the bridging/error rate that I have. No-lead part with a thermal pad, so I didn't want to mess with it. There are many visible bridges that would never have gotten through my process. And even more invisible bridges that I found, just on the ICSP lines; god knows how many errors there will be, all told. I'm going to test the boards without the thermal pad connected. If it works, I may hand-solder the next batch, myself.
 

[Assafl]

FWIW - An Optivisor is an option I use - but I don't use it for more than an hour at a stretch.