Having now heard from more than a few erectors that they received an accu-bob when they were told by a dealer they were buying a Bazooka Bob, you might want to contact the manufacturer of the Bazooka Bob(contact info above) directly, if you're unsure of what you are buying. It seems even some dealers who are honestly trying to sell a Bazooka Bob to their customer, have wound up supplying an accu-bob instead.
There isn't much info to give here as it seems this level is now off the market.
The Tru Bob according to some sources, is a one piece plastic level, 8ft long, using a pendulum to read for plumb and several magnets to secure to the column
If further info becomes available, it will be posted here.
In the end it's up to the individual what suits you best, but food for thought:
Even if you get past it that the manufacturer of the accu-bob (H.D Chasen Co) uses what can, at best, be described as "confusing" labeling by using the "Bazooka" name to push their product, the fact is the Accu-bob isn't a very accurate tool. It relies on you, the user, to make it accurate. How much are you willing to spend to get it accurate and keep it that way? There are too many red flags just in the way the Accu-bob is marketed to recommend it.
Update June 2017
The information below was correct as of Feb '17.
It now appears as if the Accu-bob may no longer be available( or have limited availability)and the company who made the accu bob (HD Chasen Co) has started selling the Bazooka Bob instead. The accu bob seems to have been removed from their site.
I'd hesitate to purchase from them until I verified with the manufacturer of the Bazooka Bob that what the HD Chasen company is selling is genuine. We've previously heard from erectors they were sold accu bobs as bazooka bobs, so a word of caution.
Before getting to other information, there are some real problems here to consider-
1) The manufacturer(HD Chasen Co) uses "bazooka plumb bob" in their URL as their page to reach the accu bob and "Bazooka / Accu-bob" in search results. Erectors we spoke with said they were confused by this. They thought they were clicking on a link to buy a Bazooka Bob and wound up receiving a different product. Other erectors insist they were absolutely told they were purchasing a 'Bazooka Bob'.... and sold an accu bob.
2) Their web page lists the item as 'Bazooka / Accu-bob'. This would seem to be more than a little deceptive. There's only one real reason to use a marketing tactic like this and has to make you wonder about the quality of the instrument they're trying to sell.
Consider an assistant or purchasing rep who doesn't know the difference between a Bazooka Bob and an Accu-bob and it's easy to see where confusion begins. Or a foreman ordering using a cell phone. Daylight, small screen, in a hurry... sees "Bazooka" and orders. Only to get something different than he thought. This happens from what men in the field have said.
"I thought I ordered a Bazooka Bob and wasn't happy when a piece of plastic junk arrived instead"
If you know the difference between the two items and mean to buy an accu bob, this isn't a problem. If you don't know the difference, it's easy to see where a problem can occur.
About the Accu Bob
Retail price $439.50
The accu bob has a foldable design and opens to 10ft. Four small magnets(30lbs pull) are used to secure the unit to the column. It has a plastic body with steel hinges and clasps to lock it in the open position.
The accu bob is advertised as a precision tool... but in order to calibrate it(per the manufacturer's instructions) and before you can use it, you must "first find a surface you know is plumb, then calibrate to zero". This means that if you're on your first column and need to calibrate the accu-bob, you must first get another instrument (or hire a testing agency) to plumb the first column, then calibrate the accu-bob. Even then, it's only as accurate as you were able to get the first column and there is no exact "zero" on the Accu bob(more on that next)
You could use a Bazooka Bob to do help calibrate the accu-bob, but then why would you need the accu-bob? There is also no real "zero". The center hole is more of an...."about there" hole. It won't give you an exact reading for plumb. Which, by definition, makes it NOT a precision instrument. This seems suited more to home use than on the job.
Many erectors have pointed to a problem with broken strings. This stems from the string being exposed when the Accu bob is folded in half.
After hearing from erectors who had purchased the accu bob, here are a some of their comments:
Not every erector was so harsh about the Accu-bob, but none of them raved about it either. The best thing anybody said about it was- "It's ok"
The Accu-Bob is no longer available on the manufacturer's site.
We found t for $399 doing a search.
Availability appears to be limited
EZ-BOB Vertical Level for Columns
For steel, concrete, walls & more
Ez-Bob vertical level for columns is similar to a Bazooka Bob. It is used for measuring steel and other vertical surfaces for plumb.
The EZ-Bob is no longer available.
There are a few other options for vertical leveling. Listed here will be other magnetic vertical levels. Below is some information to help you decide and some information on important things to be aware of.
Pictures will be posted shortly but can be found on the respective manufacturer sites.
The Bazooka Plumb Bob
Retail Price- $378
Around for 45 years or so, the Bazooka Bob is adjustable from 6ft to 12ft. Solid build with aluminum and steel construction.
Faster than any laser and better accuracy than most. It attaches to the column with a single powerful magnet(181lbs of pull). The design allows for easy attachment and removal of the Bazooka Bob from the column.
Features & Specs:
Accurate to .001"
Adjustable from 6-12ft
Easy to use- intuitive design
Lifetime warranty against manufacturing defects
There appear to be two new attachments for precast & walls and one for forms. The form attachment is the only one visible on the manufacturer's site at this time.
The Bazooka Bob retails $378. There are discounts available for multiple units at the time of this writing.
Manufacturer website: bazookabob.com
To contact the manufacturer:
BPB Mfg Co- (856) 673-1997.