Paint removal by wet sand/sode blasting

[VanDiesel99]

I've recently received a call from a company that manufactures very large propane storage tanks. They are looking for a contractor to sandblast/prime/paint a 30,000 gal propane tank. Such as one of the two shown:


http://www.totalenergy.com/Tank%20In...oAZ/tank01.JPG

I have never done any wet sandblasting(so I have a few questions) The painting part I can take care of. My question is the length of time to complete this project and some rough estimates on pricing.

They want the paint and rust stripped to bare metal then primed and painted.

[ROBERT MCLAUTHLIN]

Baking soda & sand blasting is a lot slower then power washing. Plus its a lot more to exicute. Meaning power washing is water and chemicals your going to need to add for sand or baking soda which is gonna drive up the costs.

Pricing I would price this job this way

Labor: 2 full days with 2 man crew @ $50 an hour = 32 man hrs x $50 = $1600 Power washing only

Baking soda: $40 for 50 lb bag of baking soda - 100 lbs ($80)an hour x 16 hours = $1280
or sand
Sand : $10 for 100 lb bag of sand - 100 lbs an hour x 16 hours = $160

Travel : $1 mile to and from

Gas: for power washer (based on 12 gallon tank) at $2.00 a gal = $24 a day x 2 days = $48 (x 2 if using hot water )

other factors to consider
---water, where is the nearest water source if you have to tow your water double your labor price this will greatly reduce production times

--- who has to clean up the paint chips, again double your price on labor clean up is going to kill you

--- Paint who has to paint it - oil based or latex -

Total

Labor = $1600
Baking soda = $1280
Travel 15 miles to 15 miles back = $30
Power Washer Gas = $50
Power Washer deisel = $50

Total Direct costs = $3010
Overhead Profit = $3010
Total price = $6020

Now remember that price is wet soda blasting with a power washer only no paint, no primer.

[staudend]

Definitely not by the hour!! A barn job I did that should have been worth several thousand turned into less than a G because I work fast and went by the hour because I had no previous experience in such things.
Sorry I can't help you with the wet sandblasting, I would be interested to know that as well.
Here is what I might do- get back to geometry basics and multiply the circumfrence of the tank by the length, then get the ends by radius squared times Pi (if my memory serves me right from grade school). The total square footage might be a decent starting point, because decks are done by the square foot usually at $1.00 to $2.00 a square to wash and seal. This would obviously take much more work with the sandblasting and a possible priming coat, so charge accordingly.
Now wait for anyone with sandblasting experience to help you with the price per square foot and price to paint.
Talking with zero experience with this, I might charge upwards of 3 to 4 bucks a square foot, because sandblasting might be a time-consuming task.

Nick

[ROBERT MCLAUTHLIN]

remember add for the different situations

$6020 is the price for water being on site no clean up

$9030 if you have to bring water, and fill up at home

add $1000 a days pay to clean up paint chips trust me little paint chips will take a day to clean up

[staudend]

If the tank is 40 feet long and ten feet high (just a guess), the surface area would be 10 x 3.14 x 40= 1,256. + the ends at 5x5x3.14 x 2 =157. total = 1,413 square feet @ 4 bucks a square would be $5,652. Sounds about right with Robert. Might even go 5 a square after seeing all that is involved in sandblasting.

You have just been given 2 schools of thought in regard to pricing.

[VanDiesel99]

That is a very timely detailed response, thanks Robert. I am going to go take a look at it tomorrow afternoon and take some pictures of the tank. Its a mess from what I have heard so far, but it may turn out to be a good thing. The tank had been buried and was coated in some kind of tar to keep it from rusting/corroding. The tar is still on about 2/3 of the tank. The rest is rust, there is hardly any paint left on it. The tar substance(unknown) might possibly be removed with pressure/chemicals cutting the job considerable but I am not sure about that yet. The "tar" is up to a inch thick in some places. One other problem is that the tank is laying on the ground right now in the crane company's yard. Which isn't a problem, because they can get the tank where I need it to work on it, but because it is on their property they want the mess totally contained. The man at the crane company described it as a missile that never made it to Iraq. It is 9' Diameter and 67' Long. I think it will take longer than 2 days with two men. I was looking at probably 4 maybe 5 just to clean/blast it thoroughly. I will know more once I see it personally.

Here is a look at the relative size of the tank.
http://www.totalenergy.com/Tank%20In...oAZ/tank01.JPG