undercarage

[74roadrunner440]

i have a perfectly good undercarage but my issue is i want to blast and pait the undercarqage b4 i do the body and have it painted but the guy im having do the body work says its not a good idea to that to good floor pans if i do blast it what type of blasting material should i use can i get some feed back ont this issue please its on a 74 runner if u wanted to know i wouldnt under stand why he says its a bad idea i thas surface rust on floor pans and frame rails and want to pait it up nicly just like the rest of the car will be soon thanks guys

[69*F5*SE]

I use a good respirator and safety glasses underneath a good enough blasting hood and blast with medium grit silica sand.  It's dangerous/deadly to breath silica dust. That's why you have to use a good respirator etc.  I'm not telling you to you silica sand, just telling you what I'm using.  There are other materials for blasting I just haven't had any experience with them.  I'm using a pressure pot blaster.  What I need is a rotisserie.  Blasting upside down with your back on the ground makes it a lot harder, believe me. 

[hemi-hampton]

I'd blast the underneath & then Prime it. Then move on to doing the Exterior body work & prime it. Then Paint Undercarriage. At least thats the way I usually do it. LEON.

[AutoRust]

Use black beauty to do the blast work. Its steel slag, so there is no danger like the silica sand.

[69*F5*SE]

I have an 1/8in nozzle on my pressure blaster.  Will Black Beauty fit through it. Does it break down less than how fast sand can.  I've had good luck with sand but, I'm willing to try something if it has better characteristics. 

[hemi-hampton]

I think that black Beauty is expensive if I remember right. We used to use it in our blasting cabinet for small parts, seemed pretty course. LEON.

[TylerCharger69]

Not to hijack the post or anything...but...what exactly is "media blasting"?  I've heard Chip Foose use that term on a regular basis.  And I assume that bead blasting would be too coarse for floor pans??  Sorry for hijacking...but this post made me remember to ask the media blasting question.

[69*F5*SE]

Media blasting is like sandblasting only you use different media. Instead of sand you can get plastic media, glass beads, soda, and all sorts of different media for different applications.  Some will remove paint etc. and another can remove rust etc.  Some media blasting shops even mix the media for certain applications.   Hope this helps. 

[hemi-hampton]

Plastic Media seems pretty common as this is what I usually see after having a car blasted. I assume less warpage. Soda blasting or Walnut shells finer blasting & walnut specifically for Corvettes usually. LEON.

[TylerCharger69]

Okay.....so "media" is just a term then....Cool  thanks y'all