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MP&C · 02-22-2017, 08:12 AM

I think media blasting is the best method, but used improperly, can have adverse effects.. Read the sticky here in the paint and bodywork forum on repairing sandblast damage.. So you'll see whats ahead in the remote chance that some stretching of your metal does occur. Some thoughts on media blasting....

Most damage occurs from too much pressure using too large a media. Your blaster should be using low pressure, media 80 grit or finer, and spray from an angle to decrease impact..

Many times those structures surrounding openings in doors, hood and trunk undersides, etc. will block media blasti hitting the blocked area. Someone working aggressively to remove paint from an underhood structure, for instance, may inadvertently cause a stretch in the outer skin as you are blasting the hood skin inside the opening, directly next to an area it is blocked. This may cause a buckle/stretch that is noticeable due to the immediate start/stop of media blasting due to the blocked skin. sometimes it helps to block off these openings in underhood structures or inner doors to prevent this from happening (using cardboard or duct tape or??) , and sand those areas by hand..

If your media blaster happens to mention the stretching is caused by heat, run fast, run far. The stretching is caused by the peening action of the media being slammed against the metal. (think of thousands of tiny hammers hitting your truck) Any stretching has long occurred when the heat shows up, heat is a side effect of the peening process. Increase the size of the media, it's like using bigger hammers. Use too much pressure, it's like swinging the hammer harder.

Get references from people that have taken car/truck parts to them, not barges...

02-22-2017, 08:12 AM	#6
MP&C Registered User Join Date: Jan 2013 Location: Leonardtown, MD Posts: 1,634	Re: Sand blast verses grinding and wire brush on grinder. I think media blasting is the best method, but used improperly, can have adverse effects.. Read the sticky here in the paint and bodywork forum on repairing sandblast damage.. So you'll see whats ahead in the remote chance that some stretching of your metal does occur. Some thoughts on media blasting.... Most damage occurs from too much pressure using too large a media. Your blaster should be using low pressure, media 80 grit or finer, and spray from an angle to decrease impact.. Many times those structures surrounding openings in doors, hood and trunk undersides, etc. will block media blasti hitting the blocked area. Someone working aggressively to remove paint from an underhood structure, for instance, may inadvertently cause a stretch in the outer skin as you are blasting the hood skin inside the opening, directly next to an area it is blocked. This may cause a buckle/stretch that is noticeable due to the immediate start/stop of media blasting due to the blocked skin. sometimes it helps to block off these openings in underhood structures or inner doors to prevent this from happening (using cardboard or duct tape or??) , and sand those areas by hand.. If your media blaster happens to mention the stretching is caused by heat, run fast, run far. The stretching is caused by the peening action of the media being slammed against the metal. (think of thousands of tiny hammers hitting your truck) Any stretching has long occurred when the heat shows up, heat is a side effect of the peening process. Increase the size of the media, it's like using bigger hammers. Use too much pressure, it's like swinging the hammer harder. Get references from people that have taken car/truck parts to them, not barges... __________________ Robert Last edited by MP&C; 02-22-2017 at 08:24 AM.