[fesler]

Hey guys here is some info on Meda Blasting and Sand Blasting, we have been doing medial blasting for years and have had no problems with paints. I have used the same guy for years and not one paint problem yet. It is a must to get all the old paint off the car and you need to make sure that who every you use does not wreck your car, they can do a ton of damage to the body panels if they dont do it right.

We do this to all cars we work on even Vettes with no damage, I will post a few shots of a Vette we just got out of paint so you can see how clean it is.

Media blasting is a fast, economical and sensible approach for removal of paint and rust. We use different types of media that will be best suited for the job. These media's range from coarse, medium, to soft. All used on different areas of a vehicle to balance both speed and safety for the item being stripped.

Q: What causes warping?
A: There are two things that cause panels to warp when media blasting. First, the friction of the blast can build excessive heat and warp the metal. Secondly, probably the biggest reason, coarse abrasives propelled at high p.s.i. bite into the thin metal and cause it to expand making the metal distort. Long flat surfaces are certainly more at risk of being warped than those areas that are curved or contoured.
The following are five tips that can greatly reduce the chances of warping. Low Pressure, sharp angle, continuos movement, proper distance from substrate and the most important is correct media type.

Q: What is the clean up process after media blasting?
A: The media blasting process can leave media in every part of the car. We know how important it is to remove all of the leftover media, however there will be those areas that are very difficult to clean out. 95% of the media will be removed.

Q: What type of surface finish will be left?
A: We specialize in classic automotive stripping and know the importance of using the correct media to strip the paint and rust. We use nothing that will jeopardize the integrity of the substrate. We understand that the overall finish of the paint is greatly determined by the surface you’ve started with.

Q: How much will it cost?
A: The amount of time spent to strip your restoration determines the overall cost. To save time, the selection of media needs to be determined for use on various sections of the car , for example, we will use the slag fines (instead of plastic) on a floor or a frame for faster and cleaner removal of the paint, rust or undercoating. On the other hand when safety is more important than speed the plastic media is used. Different techniques are also used for best results when balancing speed and safety. These techniques would include correct pressure, distance, angle and movement of the blast. We are constantly evaluating the best media to use for each substrate to allow for the fastest and safest way to remove coatings of paint and rust.

Q: What is the turnaround time?
A: Small items such as a fenders, doors, or wheels are usually a two day turnaround. To do a complete vehicle an appointment should be made a week in advance to coordinate the blast booth. Two to three days are necessary to strip a complete car.

Q: What type of primer should I use?
A: Self-etching primer or epoxy primer is necessary for best adhesion.

Here is some more on Sandblasting:

Sandblasting has been a very effective way of removing paint and rust from a surface. However, when the wrong media is used it can also cause heavy pitting and/or warping (metal distortion). We use mild abrasives and correct psi for damage free blasting of thinner substrates. Items like frames , wheels, suspension parts, bumpers, etc. can be safely blasted at a higher psi.

Slag Fines 60-80 grit

Used for fast removal of paint and heavy rust on thicker gauge steel while leaving surface finish acceptable for paint or powder coating. Slag fines can also be used on sheet metal at a lower psi when warping is not a concern for areas such as floors, trunk areas or engine bays.

Crushed Glass 80-120 grit

Crushed glass is a very fine almost powder like material which lightly etches the surface allowing for excellent adhesion of topcoats without warping the metal. Crushed glass is used on exterior sheet metal for paint and light surface rust removal.