Need advise on sandblasting my F100 this Sat. Lots of rust covering underneath cab and bed, and frame, though no holes except for one which will be welded next week. A little rust on the top of the bed. I bought 2 gals POR15, one gal POR Tiecoat. I'm thinking of POR15 with tiecoat over everywhere on bottom, and then do the bed, to follow later with Herculiner on bed, and some kind of rubber undercoating underneath (any suggestions?).

Any advice for sandblasting to someone who has never done it before? I'm renting a 300 psi blaster, and will use Black Beauty coal slag, goes for $7.24 per 100 lb bag.

Approx how many bags would I need?
Should I do anything special to avoid wrecking gas/brake lines?
Anything else to worry about?
Does it take long to take the bed off, since I plan to remove it to get at all the rust?
How far up toward the engine should I go? Do folks usually put something over the engine/tranny to keep sand from getting all over it?


faype02(No Email Addresses In Posts!)
1978 F100 6-Cyl 300 3-speed 2x4

 

get the truck off the ground as high as you can
if you can do it in the street away from youre girl freinds car... the sand will go everywhere trust me. think about that 100 lb bag dumped across the driveway
dress like youre doing insulation work and whear a welding mask or like face protection.
avoid soft stuff
youll find you will have good controll of what youre aimin at
its really not hard
you will go thru losts of sand depending on how thourgho you are, i went thru almost 3 60 lbs bags, but i hit everything underneath... becarful of the back window when you get the bed
cheap sand works just fine
make sure the windows are up, and the rubber plugs, under the cab, are inplace
and its time consumeing, it does great on grease and rust (loose stuff) but decent paint coats can require sanding
when you clean up use air to blow it away. water makes a big mess

i washed my truck after the first time i did it and it didnt rinse well it just stuck to everything

 

I'm in the process of doing exactly what your talking about. First, I removed the bed by unbolting it and sliding it back then resting it on some old tires then used a engine puller to hold the back of the bed up while the front rests on the back of the frame. This made it a 1 man job.

I removed ALL the lines, brake cables, brake lines, wiring... then pressure washed it to remove dirt and stuff. I then removed the drive lines TC support cover and TC.

I used a siphon blaster that really sucked, I bought a 40# pressure blaster on sale for $89 (reg $139) and used 1/20 sand for about $7 /100# and I recycled the sand via a 5 gal plastic bucked with a hole cut in the lid and window screen under lid. I used a table fan to blow out the dust as I put the sand in the bucket.

So far I've used 800# of sand and I've done the frame, under bed, TC, TC support cover... The high speed blaster will turn sand into dust at about a 10~15% loss each run. So if you don't recycle the sand you'll be buying a lot more.

Apply the Por15 in THIN coats allowing at least 20 min dry time each. Don't let the Por15 puddle up too thick as it will make bubbles and holes.

Consider the cost of renting ($195/24hr is the best I've found) vs the cost of buying (harbor freight $139)

I used a welding helmet with TAP Plastics scratch resistant plastic custom cut to fit and a thick T shirt duct tapped on, this worked OK, but fogs up too fast. Fresh air hose would be helpful.

Get a cheap clip on type light ($8 from harbor freight) because it'll be ruined. Use a fan for dust control.

It's very important to practice on a junk part to see how long it takes to 'burn thru'. Mine is a 120psi max 80 working and it will burn thru if you don't pay attention.

I left the engine installed and it sucked trying to get into all the inner frame spots. This is one reason I purchased instead of renting 3~8 hours a day and I'm still working on it! most of the time is spent recycling sand and reloading the blaster and waiting for the compressor to catch up.

At the start, a huge amount of time was spend removing the TC drive lines, bed... IF you do rent, have everything ready in advance. Look closely at the TC and decide if you can really get the underside of the frame with the TC in place. I removed everything but the engine, tranny, cab and front end and it was still a BIG hassle to reach all the tough spots.

Use duct tape for anything painted that you want to save, the sand gets EVERYWHERE.

Other notes: I used a hacksaw blade w/sandpaper to get between the bed and under bed cross supports. I cut a 6" opening in the center of each under bed support and used a welding rod with paper towel for final cleaning. I just bought a sponge to used with welding rod to paint inside the under bed supports.

Again, consider the amount of time you have to rent vs buying. I could have bought a new truck with the money I would have spend on renting.
I don't know anything about the media your talking about, but 1/20 sand is about the same price and it was what the shop said would be best.

 

My only add would be that sand works very well for removing paint, but not real great on rust. The Black Beauty slag works awesome on rust. Most of your time will be spent refilling the blaster. Make sure to wear face protection and air mask.
Dave,
79 F-150 4x4, 390 w/C6, Edelbrock carb, 33X12.50 never will be finished.

 

Good advice so far. I just used commercial grade sand from Home Depot...cheap and worked great on everything but the hardened/baked-on clay soil that has mixed with oil and stuck to the frame over the past 30 years. A sledge and chisel barely took this stuff off. Start with around 5 bags of sand and plan on recycling (in other words do the blasting on a flat, hard surface so you can sweep up spent sand). You should have more than enough for your whole chasis. I used a sand blasting hood when doing my truck. I think it would work better than a welding helmet due to the fact it has 360 degree protection and goes down to the shoulders. Make certain you have a good dust mask, but you'll still produce some nasty loogies when you're done.

The bed is easiest to remove if you have a chain hoist. Just run supports along the sides, under the bed rails and join in the center with a chain. Then just attach the chain hoist from the top and lift it up. I think there are 8 bolts holding the bed to the frame (at least on a longbed).

 

As karljay said, the sand gets everywhere. That is, absolutely everywhere you don't want it. I masked mine very thoroughly but still have sand in the lght switch, radio, and of course, in the new paint. I started mine with the cab unbolted and blocked up on the frame. It wasn't long before it was clear that a good job was impossible unless the cab was lying on its back, so off the frame it came. Do your best to get the fresh air helmet suggested by others so you can breathe, and so you can clearly see all the seams and nooks and crannies that hide rust. If you find thin spots, rip away at them until you find steel thick enough to weld. I used POR-15, but wasted my money because if the rust is gone you don't need it - good epoxy primer is adequate. However the POR-15 is excellent for the seams as it seeps in well and dries very hard. It is very thin and goes a long way. Two gallons is an awful lot.
Eric

 

I dont know if anyone has said this or not, but make sure you get at least 3 feet away, or you will do alot alot of damage to the metal.......it will make small holes in the metal, since its not that thick.......