Mobile Electronics Repair / Maintenance / Fabrication Cart proposal

[JAGMAN]

DMS Tribe,

Along the lines of another discussion on spectrophotometry, David Jackson brought up an excellent point about having a satellite electronics mini-lab available in the BioLab area. My thoughts were to add mobility to utility and instead of having a dedicated corner, to instead put it on a moveable cart with a few drawers, shelves and ideally a small tabletop.

In my background as a shop mechanic, you have your main toolbox where you keep everything you own, but have a smaller portable roll-around where the most often used tools are in easy reach for 90% of your tasks.

Given that the electronics room is on the other end of the building from the warehouse, and that it is a pain to go over there to gather soldering irons, solder, DVM, wire, etc. and then reswipe RFID access every time you want to work on a project in another room or because there is a need to troubleshoot/repair a tool like the Bridgeport or to maintenance the laser as Richard Alexander has envisioned, there is a growing consensus to make this happen.

This will also help prevent people forgetting to return any borrowed from the electronics room.

So far I see this as broken down into a few discrete sets of decisions:

1. What cart works best? (size, material construction and functionality as above)

2. What should the tool loadout / manifest be for that cart? (and this will grow over time, so there is no need to get everything right in one shot)

3. Labeling the tools as belonging to the Mobile Repair Cart so time is not wasted hunting them down.

4. I might point out that smaller parts containers be incorporated to avoid the lumping 45 different things into one drawer to prevent wasting time digging around.

Because this was becoming a separate discussion from the spectrophotometry, it was felt best to break it out into another topic.

Thoughts?

Joel-Anthony “JAG” Gray

[errant]

I like this idea. Soldedring iron, power supply, multimeter, maybe even a laptop?

[JAGMAN]

Mr. Daniel Jackson,

maybe even a laptop?

You know, something like that crossed my mind a few minutes after I posted.

But I think a small tablet would be better as it lighter (easier to hard or soft mount onto the cart) and takes up less real estate. I handle the IT for my father’s company and I recently got a deal on some Samsung Galaxy Tab 4s with a 7" screen. I traditionally thought that the gulf between a large cell phone and a decent full sized (10.1") tablet was the worst of both worlds, but I am becoming rather fond of this device.

I like the snappy response of a recent clean device utilizing the Android system, but if there is a surplus/beater laptop around, that could work as well.

It would be very useful to be able to look up part numbers, schematics, etc. while in the middle of a repair or project. But you need to be careful about environmental factor damage, leaving your email account logged in, and of course there have been concerns raised about outright theft with the idea of floating PCs in the DMS space.

The latter part I know has been discussed in other threads by better informed parties, so I have no comment on the security issue at this time.

Having a cheapo digital camera / webcam on there might be good for visual documentation which I have found invaluable for repairs or sharing status with other users. Yes, I know nearly all cell phones have cameras, but downloading directly to a central folder on whatever PC/tablet winds up on there has some advantages. That also may set the stage for documenting the maintenance log for a tool (standard practice in the labs I have worked in) but most places have trouble getting anyone to take notes, so sometimes the most promising channel is to have a simple pen and paper notebook physically attached or near the tool.

JAG

[HeatherT_EE]

I think the idea of a mobile electronics cart is fabulous! It would have
come in handy on a couple of occasions already. A wire spool rack would be
a good addition to keep it organized.

Was the plan for a workstation or just an equipment cart?

[rice81]

Here is what I have at home . . . just to get us thinking about a cart. This isn’t mobile, just a table in the guest bedroom. I just took the basic stuff and put it there although it is a bit cluttered now.

I would also add my small notebook computer for its multitude of uses in the lab - Arduino programming, online data sheets, instructional videos, etc on whatever you are doing. I think most people would have a notebook computer for this.

Some key things IMO. Keep it simple -
Scope - I have more powerful scopes, digital storage, more bandwidth, etc, but I tend to fall back on my 35 year old scope that is now $50 on ebay! Dual trace, dual timebase, 20 MHz
Current probe for scope - specific for something I’m working on - not a cart thing.
Triple power supply - Extremely useful. You always need at least one voltage. This one has macro and micro voltage control and current limiting dial as well so you won’t cook things unnecessarily. Also a dedicated 4-6 v output for TTL although that is now a bit outdated. Also button configurable as a bipolar vs separate supplies. So nice for testing devices. Dial in the voltage and current and test that relay, solenoid, motor, lamp, semiconductor, whatever.
USB supply - plug in your own cable and I also have a microusb always plugged into it. Arduino, phone, etc.
Multimeter - I have an old analog one I like.
Soldering iron and supplies - nice stand so it doesn’t fly around and melt things. Solder, solder wick, heat shrink, tape
Signal generator - don’t use it much but it can be useful. Would not necessarily have it on a cart.
Small vice or equivalent for holding work - nice to have
Power strip with lots of plugs
Good light on a moveable arm possibly with magnifier. I also have a really bright LED work light that I took off the stand and mounted to the rack.
A drawer with a few basic tools as noted. Probably left some out.
Cordless dremel and cordless drill. Useful for a lot of things with the right bits and wheels.
Lots of cables with BNC to alligator, alligator to micro clip, etc
Lots of breadboard wires and a few breadboards

Sort of along the same lines would be to have a couple of work bays that have “the basic setup”. I love the electronics area, but even I get a little overwhelmed when I walk in there. I know lots of work has gone into it and I really appreciate everyone’s contribution to that work! I am always struggling with how to organize my electronics. I think it might be more inspiring to productivity and creativity to have additional workspace without extra stuff but just a sort of blank slate or least common denominator for electronics work. Some folks will want logic analyzers and RF scopes and parts and they can get them from the main area.

I guess every area of DMS has that same challenge -
Allow users tools and freedom to do what they want
Provide an environment and classes that inspires ‘outsiders’ to become involved
Provide support for DMS as a whole with the skills of the users with the area resources

[JAGMAN]

Mr. David Jackson,

Excellent illustration!

I pondered dragging out my kits and either photographing or listing all of the components, but you saved a lot of trouble by giving a good baseline loadout.

There are some other things I would suggest like rags, paper towels, Formula 409 and IPA for cleaning up, but this is will organically grow as others add to the cart list.

I had thought about the wire frame style shelving, but if that route is chosen, I have found it best to have the sort with raised edges and thin plastic overlay inserts to prevent small parts from falling through or cable ends getting hung.

Also, I prefer at least 2 solid metal sides where you can hang magnetic holder accessories like hooks and smaller auxiliary shelves.

If cost were no object, I would think about a kitchen island, but it is desirable to have drawer faces that are at least translucent enough that you can see inside.

Here is an approximation of what comes to mind:

What I really like about this is the butcher block worktop - you can never have too much horizontal workspace. (this runs just north of $150 on Amazon and is called the Winsom Mali Kitchen Cart)

Yes, I realize that there is not enough room for all of the electronic test equipment goodies imaginable on this model, but it would not surprise me if we wind up having at least two different carts. (one for basic fabrication and repair, the other for more advanced testing and project work)

Also the needs of the Laser and Bio committees (for instance) differ significantly enough (a lot more cleaning supplies for Laser I am guessing) that a separate cart may be a logical progression.

JAG

[SRichardson3D]

My vote would definitely be more along the lines of the rolling kitchen island over a wire rack, especially if we can add a light and power strip and leave the top clean as a full work station, maybe even hang a small folding stool on that ledge at the end. Though if we go that route, I would maybe suggest we draw up plans and build our own as I doubt we could find a perfectly suitable pre-made solution.

[Clayton]

I agree with the rolling kitchen island custom build, but maybe with upgraded cassters to insure it can traverse the carpet well enough.

Also, should we consider the KISS method? (Keep It Simple Sam). Is this supposed to be an all encompassing mobile electronics station? Or only a basic diagnosis and small work station? And do you then only pull out the big equipment when needed?

So, now that I said keep it simple, another thought: Rack mount the equipment and add a monitor stand. I added a monitor stand to my work bench at home, and it’s amazing to have a full computer or laptop, off the counter. Then, if we also rack mount the equipment, rack mount would allow you to have a full computer out of the way, with a keyboard stand and 1 - 3 monitors attached to it.

Finally - add some sort of drip ledge, gullet or deflector for anything under the butcher block…it is inevitable that someone’s going to spill a soda or beer…

http://www.amazon.com/gp/product/B00K7NDBZQ/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1

The clamp can also be removed and the mast bolted directly to the butcher block. I actually recommend installing articulating monitor mounts whenever possible, frees up sooo much desk space

[Opcode]

I would imagine that Laser would want most of our cleaning supplies to remain where they are; near the laser. It wouldn’t hurt to have a bottle of pure alcohol and cleaning swabs on the cart, though.

I would expect the cart to be auxiliary to a fixed workstation. We probably want it light enough to move without too much trouble, but heavy enough not to vibrate a lot or get knocked over easily. The mental image that automatically pops into my mind looks sort of like a white-painted, obese Dalek with an open top. The sides would have many small compartments for various objects. Of course, we also want the cart to fit through our doors and narrow aisles. Bio, in particular, does not have a lot of open space.

Features and tools that I think would be useful on the cart:

soldering iron and soldering iron station
visual magnifier and light
spools of color-coded wire
heat gun
wire cutters / clippers / strippers
solder / solder wick
power bus/extension cord for local work
portable power supply (so we don’t have to run an extension cord across the shop floor)
compressed air
vacuum cleaner
log book of cart use

What kicked off this discussion in Bio is that Bio would like to share an expensive and specialized piece of equipment with Electronics: a spectrophotometer. I don’t know how much room that would require. I would imagine its main body would need to be built into the cart, so it couldn’t walk away on its own. In fact, I imagine that we would want most of the tools to be tethered to the cart, perhaps with retractable cords, so they don’t walk away. Generally, I would not expect to find expensive and specialized equipment on a cart, but we need to use the spectrophotometer in labs located on either side of the workshop door.

One idea I have for the worktop is maybe something that could be folded out from the cart and locked into place? So, like the butcher block on a scissoring arm, then locked rigidly. I hope it would be rigid, too.

[JAGMAN]

Mr. Shaun Richardson,

maybe even hang a small folding stool on that ledge at the end. Though
if we go that route, I would maybe suggest we draw up plans and build
our own as I doubt we could find a perfectly suitable pre-made solution.

The folding stool is a possibility, but there is usually a chair nearby to grab and it would take up real estate for something that we could use that is not nearby.

While I agree that find a perfect pre-made solution is unlikely, I don’t recommend building our own just yet because with the multiple roles this will probably play, I doubt there IS a perfect configuration. Close should be good enough for now and it is easier to mod an existing cart than to try and build one by committee. (that way lies madness)

Whatever deficiencies emerge can either be addressed by add-ons or just getting another cart with another set of strengths.

I do like the idea of the monitor stand, but I would have to see the drip ledge to form an opinion. Personally, I think it best to keep beverages either off of it entirely or have a can holder on the side to minimize damage.

Clayton,

Is this supposed to be an all encompassing mobile electronics station?

For the initial setup of the cart, I wouldn’t count on that. As a mechanic you try to keep the tools you use 90% of the time on your mobile cart and don’t worry throwing in the kitchen sink as well. I am concerned that overdoing it will lead to a rolling mess which will defeat the purpose.

Or only a basic diagnosis and small work station? And do you then only pull out the big >equipment when needed?

That is what I envision as more likely.

Richard, the cart as shown has a shipping weight approaching 70 pounds, so I don’t think it will tip too easily. The spectrophotometer is about the size of a paperback novel and the interface is around the size of a small router.

What did you have in mind for the portable power supply?

JAG

[Opcode]

I’m wondering how the portable power supply could work, given safety, physical and practical limitations, but I’m hoping for a battery-based solution that could power small equipment on or near the cart. A computer UPS isn’t supposed to run with a power strip, but that’s the sort of solution I have. I’m also concerned how to keep from electrocuting someone in the event the cart gets in water, either on the floor or dumped on it; maybe encasing the UPS in water shielding and using GFP? I think I saw a power station at Fry’s a long time ago that is designed for this purpose. They have a different solution this year.

Please forgive me for being negative, but chairs are not a good substitute for stools or ladders.

If the wheels are rigid to the frame, then every bump in the floor is going to be amplified in vibrations up the cart. Is there some way of putting a shock-absorbing buffer in the casters?

We could also stick WiFi on the cart, besides other electronic gizmos, including tablet/laptop and web cam. An optical scanner or camera for image capture and dimensional analysis would be useful.

Ruler/straightedge
Tape measure
DMM

It would be nice if the instruments could charge from the cart. When the cart gets back to its station, it could be charged from a wall outlet.

[AndrewLeCody]

We may be able to reallocate one of the laptops reserved for classes to this cart. Of course if someone wants to donate a tablet/laptop/etc for it, we can give them a tax receipt.

[Opcode]

I wondered if one of the donated laptops might be used for the cart. Thanks for the info!

Robert Davidson brought up National Instruments Virtual Bench in the thread “Equipment for electronics lab.” I’m wondering about implementing NI’s virtual electronics lab on the cart? Maybe Automotive would be able to use that to analyze automotive electronics? Maybe the radio corner could use this equipment in their work, too?

Speaking of Automotive, perhaps an automotive shop cart would be good for this project?

[rice81]

JAG,

That kitchen cart looks excellent. Having a good work surface is important. A few comments . . .

I used the steel shelving but mine is not moving. Something secure attached to the cart could provide a shelf or two.

Would be nice to be able to work at the area like at a desk with one’s feet below, but don’t know how that would work and it would sacrifice the lower storage area, unless the shelves sort of folded outwards from the sides, opening the middle.

Yes, bigger wheels - better.

Re the amazon computer stand attachment . . . great idea but I wonder if folks would prefer to set their own computer on the stand or papers or whatever rather than have a DMS computer there. Would it be better just to allow a space for the user’s computer as that is starting to take up some space by the time we put the case somewhere. EIther way, I like the added arms for holding a machine.

Opcode, thanks for the list. The things you mentioned that weren’t on my list are:

Extension cord to plug the thing in (I think UPS mentioned earlier might not provide enough time or power and would require a hefty battery to get even a hour or so.)

Compressed air - Iike that idea! I have a couple of small, but really high quality air compressors with a small tanks, for vehicular use. I might have an extra one with mini compressor and tiny tank that I could donate.

And I just thought of another - exacto or scalpel blades or something of that sort

Stool - good

DMM, already on the list

Measuring devices - yes . . . ruler and a caliper of some sort. I forgot. I have a relatively cheap totally mechanical Harbor Fright caliper that seems to work OK and is in good for 0.001" resolution.

And I was thinking . . . yes, KISS is important here but so is compact for the cart. A pretty basic scope would probably suffice, but a small digital, like one of the Rigol models would surely fit nicely on a cart where real estate is limited.

And logbook - good idea to document use and collect suggestions.

I may throw together an online spreadsheet with some of these ideas and let’s keep working on it.

[JAGMAN]

DMS Tribe,

Some comments on the latest suggestions for the mobile cart:

1. We need to either be aware of “feature creep” and moderate expectations accordingly and/or prepare to have more than one cart that is dedicated for different functions. (Ops Repair / Electronics / Bio / Automotive) as with the excellent suggestions which are pouring in.

2. I suggest we just go ahead and get one cart (I am for the kitchen island) and use that as a prototype as it is often useful to just start throw different things at the wall and see what sticks, but having a physical object to interact with makes it easier to get this rolling. (pun violation)

I’m wondering how the portable power supply could work

The more I think about it, the more I believe we should just start with an extension cord and a power strip and MAYBE a small UPS that could power/charge very small electronics. (like the Labquest Interface) The logistics brought up by Opcode (Mr. Richard Alexander) makes a larger scale power source seem unwieldy and problematic.

Please forgive me for being negative, but chairs are not a good substitute for stools or ladders.

Richard, that is quite alright and your comment highlighted my misunderstanding of what was meant by a stool. (I initially thought that was intended for just sitting down to work) Now it is apparent what was meant is a compact folding stepladder for the purpose of reaching higher up.

But regardless, that does not seem like a first choice item to put on there and it would take up too much room in my mind. It would help if some clarified with an example of why that would be useful instead of just having one stored in the warehouse. What am I missing here?

If the wheels are rigid to the frame, then every bump in the floor is going to be amplified in >vibrations up the cart. Is there some way of putting a shock-absorbing buffer in the casters?

I am not against upgrading the casters if there is a demonstrated need, but how about getting the cart first, loading it a bit and then running it around gently to see what actually happens with the physics?

Speaking of Automotive, perhaps an automotive shop cart would be good for this project?

I considered that and I don’t believe it would be unless it is used for the Automotive group. The reasons why are because an automotive cart is designed for quickly reaching a bunch of hand tools and temporarily storing bolts, parts, fluids, etc. without dropping anything on the floor so it is characterized by having raised metal edges all the way around to contain items.

This is the same feature that would be an annoyance with Electronics. For one, you don’t want a conductive metal surface all the way around. And then the raised edge tends to interfere with working on a project directly on the cart. In automotive, your actual work is focused on the car, not the cart - not the other way around. Does that make sense? I own over a dozen carts myself at home including several in my garage and I have a feel for what makes a convenient work surface.

Best Regards,

JAG