soda or sand blaster

spanishmak · #1 09-04-2010, 05:56 PM

hey everybody.Can anybody tell me how much a sosa or sand blaster costs and also i have one of those pancake compressors will it work or not to take bottom paint off a 21 ft v 20,also will a sandblaster work also

step up here · #2 09-04-2010, 06:59 PM

get it soda blasted . your pancake compressor is only for small jobs very small . eg nail gun, filling a tire etc.
if you are going to paint the bottom with anti fouling paint look into a barrier coat first then use a high dollar multi season paint. outstanding results. you wont have to paint the bottom every year!

Destroyer · #3 09-04-2010, 07:53 PM

Spanishmak, I agree with everything that Step up here said.. Please allow me to add a few things.

First, if you're going to trailer the boat there is no reason to paint the bottom. Bottom paint is only for when you leave your boat in the water in a slip. It prevents marine growth due to it's leaching action. An unpainted hull is very smooth. The smoother the hull, the less resistance in the water, the faster and more economical your engine runs. (Plus, personally, I think that unpainted hulls just look better...but that's just me)

Second, NEVER sand blast your hull.. the sand will eat through your gellcoat and fiberglass like a fat woman with a chocolate cake.. It will be gone before you blink.

Soda blasting works differently than sand blasting.. when the Bicarbonate of Soda hits the surface of whatever it's being propelled at the grains of soda actually shatter from the force of the contact.... the force of that shattering propels the remains of the grain sideways, and in the process they scrape away the paint off the hull. Soda is an extremely friable material that micro fragments on impact. It literally explodes away the surface material without damage to what's underneath. Multiply that effect by thousands of grains per second and you see how soda blasting works. You need a big nozzle, a really large compressor, etc etc. It's not a job for the home handyman.. call in a professional. They normally charge about $9 a linear foot .. so a 20 foot boat will be about $180 plus travel, set up and clean up.. Under $300 total.

Also, be aware of the fact that you may have blisters in the fiberglass hidden under your paint, depending on the age of the boat, maintenance, etc. If that's the case you'll have to recoat the bottom, but if you're going to trailer the boat you don't want to recoat with a soft anti-fouling paint.
Instead go for one of the plastic based hard shell paints. It will last longer and will not mark up your trailer the way that a soft paint would.

Hope this helps a little

willy · #4 09-04-2010, 09:45 PM

Destroyer, you have got to add a zero to the job for soda blasting. Even then 90 a foot is a very good price. Most are 120 a foot. The prices I wa quoted for my V20 were about 1100 so keep that in mind. Otherwise what you said is right on and would be the preferred method.
The other viable home based method would be the chemical stripper which would be the most economical but the work is tough and long. But I have seen it done on two boats and it actually comes out the best I believe depending on what you are going to finish your boat with afterward.
If you are going to paint your hull with and epoxy based paint then the soda blast is the best because it actually preps your hull while stripping it for a paint type finish saving you hours of sanding etc.

garagenc · #5 09-04-2010, 10:15 PM

Also check into blasting the hull with pecan or walnut shells. It does a very nice job. Just ask the company you are thinking of using to blast the hull if they can do it.

Destroyer · #6 09-05-2010, 03:00 AM

Quote:

Originally Posted by garagenc

Also check into blasting the hull with pecan or walnut shells. It does a very nice job. Just ask the company you are thinking of using to blast the hull if they can do it.

Not sure I agree with you there Garage.. I've heard (no direct experience) that both of them do the same thing as sand.. I know they are softer materials, etc. but they still hit the hull harder than the soda..

Willy, you're absolutely correct.. when I looked up the prices it was $90 a foot, and I typoed 9 instead.. then componded the error by multplying 9 x 20 .. I hate getting old and having these brain farts.. of course as I get older I'll forget I had them.. so I guess it's all good in the end...lol

spanishmak · #7 09-05-2010, 10:17 AM

yeah i just wanna get it off my boat,i hate the way it looks and i trailer my boat(only 5 minuta drive to boat ramp) in hudson beach fl.I do like the way a boat looks with regular paint all the way through instead of bottom paint if u dont need it and i dont.I really appreciate the replies.How do you do this chemically instead of blasting.Time and work is not an issue I love working on boats and learning about working on them

willy · #8 09-05-2010, 10:33 AM

There are several diffrent brands, Home Depot sells one in gallon cans that many recommended but I dont have the name in front of me, I will get it if you need it.
It is a stripper with a thick consistency that you spread on and let sit for a few minutes and then use like a plastic or metal putty type knife of varying sizes and shapes to scrape off the paint which it softens.
If you have multiple heavy coats of bottom paint it can take some time becuase of re-applications to get thru it. It works real well on one or two thinner properly applied coats.
afterward you use a cleanser to clean off everything and lightly sand and fair any bad divits etc. if needed and paint your epoxy paint of choice.

garagenc · #9 09-05-2010, 12:11 PM

Hey D
That's why I said for him to ask his blast guy if he has any exp with it. They can blast at a lower psi and it wont hurt the gel coat. I've had 2 experiences with blasting that way and they both came out ok on private boats. The shells can be be fine or coarse depending on what the surface is behind what you are trying to remove. When the shells are fine they work like soda. I became aware of it about 20 years ago when we used it at a Navy Yard on steel hulls, then we started working with a company that refined it so we could do fiberglass hulls for the "Admirals Barge" and all the fiberglass hull launches.

Just make sure your guy has experience with using the shells.

spanishmak · #10 09-05-2010, 12:14 PM

definitely willy if you could get me the name brand i would really appreciate it I really wanna get this bottom paint off but with this economy the way it is I just cannot afford to get this boat soda blasted,but i will spend the time to do it myself this way(it is alot easier for me to get the job done myself little by little than to come up with money for this sandblasting in one shot you know!)any help would be GREATLY appreciated