Mobi arc on-board welder

Mobi arc on-board welder

coldair

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1986 cj7 in the works,
1996 F350 crew cab with a 5.9 cummins
Found a great deal on a brand new Mobi arc on-board welder has anyone used one of these?
 
LG I was aware that they are no longer made. I found a never installed new in the box a private party has for sale.
 
Here's some info-Don't know if you have seen it.
mobi-arc 200x

Trail Welder Comparison

Me-I carry 10' of 4/0 arc welding wire made into jumper cables and various diameters of 1013(mud)rods(por mans amperage control)for field welding with a battery.

With no factory support for this welder-Not sure I would take a chance.
LG
 
This is probably esoteric rambling...

I've turned about every type of common alternator into a welder/generator at one time or another,
Including using a Leece-Neville for AC, High Frequency AC, DC, Reverse DC,
This gave me MIG, TIG, Stick and Plasma Cutter capabilities.

The problem with all that was the SUPPORT GEAR!
You will have more junk to haul around...
Building brackets for the alternators, control boxes, ect.

--------

What I do now is Dual Batteries,
And a set of jumper cables set up to chuck a welding rod.

First off, I don't think I ever welded Aluminum IN THE FIELD,
So carrying around even a small bottle of shielding gas and TIG rig was a waste of time and space.
That meant I didn't need High Frequency AC.

Secondly, An alternator produces in AC, which is rectified to DC.
Common Rectifiers weren't designed to handle the 'Dead Short' of welding, so you will usually go through rectifiers pretty quickly,
Or your duty cycle will be about 30 seconds at a time.

Third, Most everything you will do in the field will be common steel, no need for tricky rods or welding wire,
So a few common DC welding rods will do just fine,
Or the spool guns with Flux Core wire instead of gas shielding (MIG).

Fourth, What they DON'T tell you about those common alternator units,
They use the alternator CASE 'GROUND' as negative.
That means NO STRAIGHT POLARITY WELDING on your own vehicle!
Positive electrode ONLY, Negative 'Ground' ONLY...

VERY LITTLE PENETRATION like this!
The weld will mostly sit on top the base metal.

(Welding STRAIGHT polarity is POSITIVE 'Work' and NEGATIVE Electrode. This will give you a MUCH deeper weld)

With two batteries, you can produce enough current to weld just fine with rods...
And with batteries, it's EASY to make disconnects from the vehicle, a SERIES adapter for your jumper cables,
And do STRAIGHT polarity welding on your own vehicle since the electrical system (Batteries) are no longer ELECTRICALLY attached to the vehicle.

------

Most Rods burn just fine with 18 to 24 volts,
And there aren't many common, Reasonable Diameter rods you can't burn at around 60 to 85 Amps.

Smaller diameter rods give you DEEPER digs, but narrower puddles,
While wider diameter rods give you wider welds, but less penetration.

Spool guns use less current, so they can weld LONGER off batteries without running them down,
But give SMALLER DIAMETER, SHALLOWER welds,
Which I found out you don't do much of in the field.
Most breakages/repairs are 'Heavy Metal', something that was heavy built, broke, and you need to cobble together to get in...

----------

This is from Experience,
I've tried a bunch of the market offerings,
Many of my home built units when the market units didn't work for what I was doing.

Most of my 'Field' welding was using my jack handle to fix a drag link that bent/broke, welding on brackets that took a beating and finally failed, ect.
Not much 'Sheet Metal' work in the field...
The spool guns did OK, but were SLOW and took a lot of maintenance, and they took up a lot of room in the vehicle.

TIG is even worse...

I carry jumper cables, and with some 'Anderson Power Pole' type connectors on the battery, and a 'Series Yoke' to connect the batteries in series for 24 volts,
There isn't much I've not been able to fix in the field,
If we could find all the parts!
 
Don't get me wrong,
Having a spool gun (MIG or Flux Core Wire) is a good deal,
Just 'Field' repairs usually consist of things a rod works better, and is MUCH faster.

The little spool gun units are mostly Flux core wire, which doesn't dig deep and spatters, and there is the storage issues again.

TIG takes skills and a controlled environment, but makes the best welds.
Wind will take your shielding gas away,
The absolute need for a gas tank, regulator, TIG torch and correct input current means a LOT of :dung: that's hard to store in a Jeep.

I've just found that batteries give you perfectly SMOOTH DC stick welding,
Jumper cables are a staple to start with, so no extra storage other than goggles or helmet and the rods.

The Series Yoke, and the 'Anderson' connectors are under the hood, so no storage space lost in the vehicle, other than helmet, rods, jumper cables, none of which is particularly sensitive.

If you NEED welding, you probably already have a winch,
So you probably have dual batteries anyway,
So why not use those dual batteries to do your welding with?

The dual battery arrangement kept me from having to change 'Weld-A-Nators' (Alternator/Welder) when I needed to weld,
Powers the winch,
Gives me nearly complete redundancy on getting the vehicle started,
And dual batteries will get the vehicle home *IF* the alternator fails...
Failing alternators are very common with welders that attach to the alternator,
While batteries will supply a welder fairly easily and still start the vehicle, without failing.

The other point with batteries is they will weld 'Stright' welding polarity, on the host vehicle.
Something you CAN NOT do with an alternator based system since the vehicle has to be running to weld,
And since the alternator is 'Grounded' negative,
You will cook the charging system with 'straight' welding polarity.
(Ask me how I learned that...)

Since the engine DOES NOT have to be running to weld off the batteries,
And since the charging system isn't hooked up while welding off batteries,
You can dig deep with the rod in 'Straight' welding and not cook the charging system (or radios, or anything else polarity sensitive, like ignition modules).

Thats my APPLICATION,
Others might have different applications that require different equipment...
 
Found a great deal on a brand new Mobi arc on-board welder has anyone used one of these?

:)
This is a good debatable subject about on-board welders, but as many have said here the complexities vary across the spectrum, I've seen guys with all of the brands and all seem to have issues notwithstanding I've seen a few self implode and leave the same truck trying to do the fixing the one that now needs the rescue.

Personally I like to do all my Tig, Mig and Arc in the shop , along with spending time maintaining and servicing your truck long before it ever see's a trail.

My CJ has been dragged all over the Western States hunting Mule Deer years ago.......I mean 3 of us 40-50 miles off the pavement on remote BLM land for 10-12 days where a trip in is 3-4 days and maybe longer out if Weather is an issue and although we fixed a few things welding was never needed.

So who needs a welder? As Team Rush mentioned a few sticks of welding rod and Jumper cables works wonders.

Bottom line you have to take care of your equipment and learn to understand yours and the jeeps capabilities. A small trailer w/supplies and Fuel is what we carried. 60 gallons of it plus what was in the Jeep............

Weather is by far your worst enemy being that far off road in Remote areas.

Take care of your Iron before you leave and enjoy the trip!

:D:D:D:D
 
Tarry99,
That's kind of the point.
When you make the transition from weekend wheeler to serious wheeler,
There are a LOT of things that needed changed...
And a lot of guys don't know where the weak points are until they give way.

The more serious you get about wheeling, the less people that can/do go with you.
This means you are on your own more and more,
Being more capable is a requirement,
And nothing breaks back at the shop where all the welders are... (I wish it worked that way! :D)

Stray pieces of strap iron, angle iron thrown into the tool box and some welding rods will get you out of trouble you didn't know existed before it broke!
 
Tarry99,
That's kind of the point.
When you make the transition from weekend wheeler to serious wheeler,
There are a LOT of things that needed changed...
And a lot of guys don't know where the weak points are until they give way.

The more serious you get about wheeling, the less people that can/do go with you.
This means you are on your own more and more,
Being more capable is a requirement,
And nothing breaks back at the shop where all the welders are... (I wish it worked that way! :D)

Stray pieces of strap iron, angle iron thrown into the tool box and some welding rods will get you out of trouble you didn't know existed before it broke!

:)
Oh I had a few sticks of Arc Rod tucked under the seat , that lost most of the flux from age.

Your right nothing breaks while it's in the driveway.......15 years of dragging that Jeep everywhere and never needed a welder........drove the tow vehicle 260 miles round trip to a wrecking yard in Fallon , NV once and stripped some Dana parts from a Scout though..........truth is half of these folks with trail welders can't weld anyway! and without a grinder of sorts the repair is at best questionable............point is: You need to take care of your equipment.

I carried more things like Ignition and carb parts than anything else. No GPS back then , basic survival gear a compass and sector maps. The ranchers that I knew where we gained access to the remote areas knew we were in there and knew we would be back for our tow vehicle sooner or later!

:D:D:D:D
 
No matter how good the maintenance, there will be breakage! Just a fact of life.
Most of the time, it's things like U Joints, the occasional spun axle flange
(Which a welder is the ONLY way to fix it and get you moving again),

It's just a good capability to have if you have dual batteries and jumper cables.
A set of goggles and some water tight welding rods and you can patch things up.

It's not the 'Tow' that bothers me, Everyone will need a tow sometime.

It's the LONG WALKS to get someone to tow you!
I'm not in my 20s anymore, so humping 15 or 20 miles is on my 'NOT to do' list.

Farms/Ranches need a LOT of maintenance, which is why I started building alternator welders back in the early 70s when alternators started cranking out enough amps to do the job.

I'm by no means an 'Expert' welder.
My welds look like the bottom of a chicken coop,
But I get things put back together well enough to get the item working again, even if you have to take it easy on it.
Nothing like trying to get a 30 foot wide farm implement out of the field, or some huge tractor, back to the shop.
Much easier to drive it!

You are correct on having a grinder, something to cut/clean metal with.
The 'Farmer Rods' will burn through most things, but for some serious repairs, a grinder is a good idea.

I have an electric on board air compressor with fairly large air tanks mounted UNDER the vehicle.
Lots of room for reserve air under the vehicle,
Tanks are cheap, they are all over every big truck in the county, the junk yards are full of them.

Since I have dual batteries, an electric compressor makes sense,
And it doesn't have to be mounted on the front of the engine in the way,
It can go anywhere you can run wires/air lines to...

Air grinders are smaller than electric, and since I carry an air hose anyway.
The air hose is even dual purpose.
It's fuel line with air chucks on the ends.
If I need an air line, it's there.
If I need fuel line, I cut a piece off.

The entire idea of redundancy is dual use or back up...
Since the air compressor is in place with the tanks,
I use the air compressor to pressurize the distributor cap, axles, transmission & transfer case.
Parts with positive pressure won't allow water/crud in,
So the little Jeep runs happily with the distributor under water,
And I don't have to change the axle/tran/transfer lube every time I wade off in deep water...

Like I said,
REDUNDANCY is a beautiful thing!

Nothing like having a jack handle that will repair the drag link,
Thick enough to use as a pry bar,
Thick enough to roll fenders away from tires,
Having a socket adapter welded on the side so it works as the ULTIMATE breaker bar,

Compressor/Air hose that keeps water out of the drive train,
Compressor that works air tools,
Air hose that doubles as fuel line,

THINK "SYSTEM" and "RESERVE",
Not 'Item'...

If you are going to carry the weight around,
Make it do double or triple duty.

Dual batteries have enough RESERVE they will get you in if/when the alternator fails.

Isolated Dual batteries will get you started when the primary runs down (something left turned 'On', Plates break loose in one battery and short out a cell, ect.)

Dual batteries make the winch SO MUCH MORE EFFECTIVE,

Dual batteries give you the ability to weld.

Dual batteries give you the ability to run an inverter (110 volt power) in the camp.

Dual batteries gives you the ability to 'Lend Power' to something else while still keeping the Jeep running on one battery...
(Camp power, Farm Tractor, Broke down person, ect.)

Air compressor give you the ability to air up/down tires,
Fill air mattresses/float toys in camp,
Keep the crud out of drive line,
Run tools, ect.
Air tools are also VERY compact when compared to battery powered tools...
 
Thanks for all the inputs guys! I've run duel battery's before just wondered about this setup. I passed it up
 
That is quite the laundry list you have there,

Yes I have dual batteries, Yes I have a few sticks of DC Rod in a tube & jumpers, Yes I have an extra U-joint , belts, water hose, duck tape , bailing wire, elec. wire , tools , on board air with a 2 gallon reserve tank, recovery cables, snatch block and rope , my normal survival gear that includes water tabs, energy bars, maps , signaling mirrors, fire starters, tire repair and wood cutting equipment.

Your right you cannot adjust nor prepare for the unknown, which also means you can't carry enough spares or equipment to get you out of every jamb. I like to do all my preparation and maintenance before I leave. And what spun axle flange are you talking about on a Jeep? An early tapered axle or a AMC20? Neither of which I would leave the house with , just for that reason!

15 years of tramping all over the Rockies from New Mexico to Montana we have had our share of Oh shxt moments , but never have I needed a welder nor could not fix something on the trail.

Is that just Preparation or is it respect for your Iron or just understanding that taking a different line may make the difference.....Are hunting operation behavior was pretty simple, once in remote areas we were already in survival mode and not taking any unnecessary chances , we knew we had are butts hanging out there , just the things you learn through the years.
 
Thanks for all the inputs guys! I've run duel battery's before just wondered about this setup. I passed it up

Aside for the engine, the single most productive thing you can have on a Jeep is Dual Batteries.

Alternator dies, No Problem, you have enough battery reserve to get someplace you can get an alternator.

One battery dies, No Problem, you have a second, just unplug the dead battery and continue as normal.

Have a winch? Inverter for 110v power? 12 volt powered tools? Electric air compressor?
No problem, you have LOTS of battery reserve to do the jobs you need to.

Need to weld something?
Need to Lend Power to someone with a dead battery?
Need a battery in camp for fans, radio, ect.?
No problem with high current quick disconnects on one or both of the batteries.

Need to get that 'Bucket' started in REALLY COLD weather?
Nothing like a second battery kicking in and cranking the :dung: out of that engine!

Second battery, second starter relay ($15 to $20) on the second battery makes everything but the starter motor REDUNDANT in the starting circuit.
No more 'Solenoid' (Starter Relay) problems,
You probably won't know one starter relay failed until you do maintenance...
No more being stranded by a $15 'Made In China' failure prone part...

With a $10 common automotive relay/socket added,
You can ISOLATE your 'Emergency' battery,
In the event something shorts out and drains the 'Primary' battery...
No worries about the 'Kids' leaving something turned on, or forgetting to turn the head lights off...

------------

The batteries you choose are going to make the system more redundant, while giving you more useful energy.

With TWO batteries, the load is split 50/50 between TWO batteries,
So your Deep Cycle batteries will live longer...

Deep Cycle batteries are made to SLOWLY be Charged/Discharged,
So guys that RAPIDLY Charge/Discharge a single Deep Cycle are damaging that battery.

With TWO batteries, neither battery gets charged or discharged quickly, so they live longer.\

-----

'STARTING' batteries are designed to charge/discharge quickly,
BUT NOT DEEPLY DISCHARGED, which will damage them.
A second 'Starting' battery will divide the load between two batteries,
So you don't damage the single Starting battery.

-----

My personal favorite is a 'Marine Starting' battery.
It has qualities of both 'Starting' and 'Deep Cycle', while not exactly being either.

Heavy built for rough service,
Capable of recovering from fairly deep discharge,
And capable of charging faster without damage than a true Deep Cycle,
A matched pair of these are good choice for what I do with my Jeep.

Everyone will have to assess the APPLICATION for their own vehicles,
I'm just saying that after 40 years of experimentation and assessment of parts,
This is the most PRODUCTIVE & RELIABLE system I've found so far, USING COMMON PARTS that can be found in any parts store or junk yard...
 
Tarry, sounds like you have a capable rig.

The point I'm trying to make here is,
A ton of people WILL NOT change the stock parts until something fails...

The reason I have welding capabilities is I wheel alone much of the time,
Make farm repairs,
And I'm an old, broke down guy that doesn't like to walk...

Others will not find the weaknesses in some of their Jeeps,
While others will, and usually at the worst possible time.
(Murphy's Law)

A small PVC tube with some welding rods sealed up in it,
The tighter you pack them, the less they break the flux off, and different diameters/types for different jobs...

Some Jumper Cables with a copper rod holder jaw installed, (Copper jaw helps with jump starts too!)
And a set of welding goggles will get you out when something like an AMC20 axle flange decides to give way at the worst time...
Just weld the hub to the nut, the nut to the axle.

We all have to learn this stuff by the seat of our pants,
I'm NOT going to knock someone that has a trail welder...
It's saved my butt more than once while I was learning,
And it saved other people that had issues on the trail since I will stop and help...
 

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