Topic: Phosphating 101 -

[jwc66k]

I've been phosphating for over twenty years and this is what it entails. There's a lot of items involved in the phosphate and oil process. Remember, you are playing around with acid.
1. It only works on steel and iron parts so don't try it on aluminum, brass, copper or non-metallic items.
2. Items to be phosphated must be clean. More on that later.
3. Use only stainless steel tanks and tools. One exception is the rinse tank.
4. I preheat three gallons of water in my kitchen and pour what I need into the stainless tank heated by propane.
5. Store unused chemicals in HDPE containers.
6. I found that air drying works best, in temperatures above 72F, in the sun and with a bit of breeze prior to the oil step.
7. I don't recomend drying in an oven as it leads to rust forming. It may be a matter of timing, but air drying works.
Tools - (see pictures)
1. Stove. I like propane. Electric stoves don't seem to last, don't produce enough heat and are too small. You need at least 180F water to phosphate.
2. Tanks - All stainless steel. You can get them from restaurant supply stores, Wall-Mart types or e-bay. My rectanglular tank is big enough to do a hood hinge (12 3/4 X 11 5/8 X 3 7/8), but you have to "splash" the spring retaining arm. The fish poaching tank (19 1/2 X 6 3/4 X 4) works well on long items, center links, strut rods, etc, but you have to swap ends of the item after 45 seconds to a minute. The round pan is for metal blackening and the sauce pan (stainless) is for small batches, mostly nuts and bolts.
3. Tools - Goodwill. I got the long hook from a hardware store. It is stainless (all stainless is expensive). It was 36 inches lon and I cut it in half and promptly lost one piece. Bend as necessary.
4. Metal blackening - Eastwood. Just get the metal blackening solution as the rest of the stuff is a joke. Well, the HDPE container is nice to have.
5. Rinse - A number 3 wash tub works. I also use a plastic bucket for small batches.
Not shown:
- the phosphoric acid concentrate I use. More on that later.
- a 1 cup Pyrex measuring cup, to get the correct mixture from the phosphating concentrate. More on that later.
- a thermometer - a deep fat fryer type.
- stopwatch. It's important.
- a large 5 gallon plastic bucket (paint, dry wall, dish soap types) for used phosphate water. After the water cools and I don't have any small batches to do, I pour the water into a bucket with a couple of scoops of Borax to neutralize the acid.
- neoprene gloves.
- hooks made from coat hangers to air dry items.
- shop towels.
Jim

[jwc66k]

Part two - Chemicals -

Metal blackening acid: Eastwood www.eastwood.com  Metal Black Concentrate replacement to get a dark looking part prior to phosphating. Mix 8oz concentrate and one quart water (Eastwood is very lax on their instructions) in a HDPE (High Density PolyEthylene, a number 2 in the recycle triangle) container with a HDPE lid, then pour what you need into a stainless steel mixing bowl. When you are done, you can pour the Eastwood black solution back in its container for reuse several times. Don't try any metal lids or aluminum foil in the lid, they corrode away. I used a glass container with a plastic lid for a while, don't bother. Rinse the mixing bowl in the rinse water when everything is done. The entire kit is a waste of time and money, it don't work and looks terrible.
(I left several bolts in this solution for an hour just to see what would happen. After phosphating I was surprised to find that after they were submerged in water for several days they looked great and did not rust. I intend on repeating the procedure.)

Phosphoric acid: E-Phos 630 for the phosphoric finish, available from: EPI www.epi.com There are other sources. I got mine thru the plating shop that does my clear and gold zinc plating. I don't know if EPI sells to the general public but they sell in bulk as in a case with 12 bottles. I don't remember the cost but my plater sold me two quarts and kept the rest as he was thinking of doing some phosphating for a customer. As it is a concentrate, I use 1 to 3 oz per gallon of water depending on what final results I desire. The mixture must be heated to over 180F to "cook" items properly.
I used another product called "Rust-Mort 69504" (the 4 equals a quart) from SEM Products  http://semproducts.com/ It's available from Amazon and many auto body shop supply stores. I "adapted" its use because the main ingredient is phosphoric acid. Again, I use 1 to 3 oz per gallon of water depending on what final results I desire. The only drawback is a fine lite layer of crystals that sometimes appears from the "cooking" process. 

Rinse water: right from the tap.

Oil: New motor oil, used motor oil, transmission fluid, WD-40. This is the tricky part.
- I tried heating new motor oil to 400-450F and succeeded in stinking up the neighborhood. Air temp clean oil seems to work sometimes if left parts are left for a day, but a hood hinge requires about three gallons of oil.
- Used motor oil has acid in it so you are defeating your goal. I've read that others use different "shades" of used to get the desired dark finish.
- Transmission fluid was suggested but I haven't tried it.
- WD-40. It works.

Arm and Hammer Borax laundry soap: used to neutralize the leftover phosphoric acid solution after it cools. A cup per gallon of water solution should do the trick. Let the water evaporate and then throw what remains in a garbage bag and then into the garbage. 
Jim

[cobrajetchris]

Sounds complicated, dangerous, messy and expensive, I think I will just send my parts out for phosphating to someone like you that has experience. Do you offer this service or just do your own parts?

[CharlesTurner]

Sounds complicated, dangerous, messy and expensive, I think I will just send my parts out for phosphating to someone like you that has experience. Do you offer this service or just do your own parts?

Phosphating is about one of the simplest coatings to work with.  I wouldn't consider it dangerous at all.

[CharlesTurner]

Good write-up.  The only thing I would add is to make sure the parts are dry before coating in oil or whatever.  I usually blow-dry with compressed air before putting in an oil bucket.  I just use a straight 30W motor oil, new, nothing fancy and soak the parts for 24 hrs.  What's nice about soaking in oil is that it penetrates the phosphate surface.  Once I've gotten all the oil off with paper towels, I let them sit out for a while.  Can wash them with dish-washing detergent, which removes oil from the surface so it doesn't attract dust.

[jwc66k]

Part three - Hardware Restoration - Preliminary

This applies to nuts, bolts, screws, washers and other small steel parts like clips and brackets. My intent was to do a lot of items with a minimum of hands-on labor as I had 4 Mustangs at the time.
1 I got a five gallon bucket of Mustang parts from an auto dismantler about every other month for the last 20 years. As I empty the bucket, I sort hardware into screws and bolts, nuts and washers, special parts, non-metallic parts and everything else. In this and every following step, if the part is broken, threads damaged, too much corrosion or beyond use – I toss it.
2 Soak all hardware in solvent such as Berrymans B12 for a week. I use coffee cans with holes punched in the bottoms and a small chain as a handle in a paint can, with a lid, with the Berrymans. I also have a 5 gallon metal bucket with Berrymans to strip paint from medium size items. Keep a lid on it.
3 After a week in the solvent and while still in the coffee can, rinse in soapy water, as in a deep sink where the laundry water goes using the laundry water.
4 Empty can on a shop towel and allow to air dry for a couple of days. The items will be dirty but the paint and crud will be soft. Put more hardware in the can and return to the Berrymans.
5 I use a two drum rock tumbler (Thumbler’s Tumblers - got the idea from my Postman) using the metal filings from brake shoes and rotors as a cleaning (abrasive) media, to clean most of the crud and rust off the parts. Your friendly local tire store is the source of the filings. Don’t put wet, moist or damp items in with the metal filings, everything will rust. It takes between two and five days at 24 hours a day to tumble parts clean. A week’s worth of tumbling won’t harm most metal parts. Use a straining screen (TP Tools) to separate the filings and hardware when done. I get about four loads (a months use) then toss the filings. On clips with the plastic/rubber insulation you may have to remove the plastic by hand and then return to the tumbler.
6 Dip tumbled items in kerosene to remove filing dust and to give a protective coating to prevent rust. Do not use paint thinner or gasoline.
7 Allow to air dry for a day or two.
8 Sort into containers for whatever you want to do next, phosphate and oil, paint, clear zinc plate, gold zinc plate or cadmium plate. 
9 An Eastwood Vibratory Tumbler is an asset. I use TSP (Tri-Sodium Phosphate available from Home Depot) and water with the Eastwood green pyramids.
10 What doesn’t work “well” is a wire wheel. It’s time consuming and will tear up your fingers.

Sources:
 -TP Tools & Equipment www.tptools.com
  Bead blasting cabinets, blasting media, restoration tools, paint
- Eastwood www.eastwood.com
  Bead blasting cabinets, blasting media, restoration tools, paint, vibratory tumblers, chemicals
- Thumbler’s Tumblers http://thumlerstumbler.com/
  Rock tumblers.

[jwc66k]

Good write-up.  The only thing I would add is to make sure the parts are dry before coating in oil or whatever.  I usually blow-dry with compressed air before putting in an oil bucket.  I just use a straight 30W motor oil, new, nothing fancy and soak the parts for 24 hrs.  What's nice about soaking in oil is that it penetrates the phosphate surface.  Once I've gotten all the oil off with paper towels, I let them sit out for a while.  Can wash them with dish-washing detergent, which removes oil from the surface so it doesn't attract dust.

I ain't done yet.

[jwc66k]

Hardware Preparation - Final - Phosphate and Oil, Zinc Plating, Painting
1 Bead blast everything. Use glass beads. I like TP Scatblast media made from crushed glass. It's more abrasive which saves time. There are other media: round glass beads, walnut shells, plastic, steel grit, aluminum oxide, soda, etc. You need a bead blasting cabinet to do any of this. I got my cabinet from TP Tools over 20 years ago and it shows its age. Eastwood has them as well. Mine is big enough to do 15 inch rims. I tape a 33 gallon black plastic trash bag over the open door to blast sway bars. If you do get a cabinet you must get a vacuum system otherwise you won't be able to see what you are blasting because of the resulting dust and the used media needs to get tossed. Glass beads are not considered a hazard (TP provides info about that) but what you blast off may be. A general use shop vac lasts about a week before the bushings get wore out from the dust so don't bother. A large compressor is needed to provide the air. Mine is a 6hp 33 gallon direct drive Craftsman. It's the third one I've owned and each one was an upgrade to a larger size. I sold the others to grateful neighbors with kid's bicycle tires, soccer balls and footballs to air up. 
2 To hold screws and bolts use plumbers tape. (See picture.) That's the perforated one inch wide metal strip that holds water pipes to floor framing. The large holes will retain 5/16 dia screws, bolts and studs, the smaller hole will hold 1/4 inch dia items. You may have to tap the holes to insert the items. I have about a dozen well used strips about 8 to 10 inches long. Start blasting the head of the bolt/screw first then under the head and star or disc washer. After you bead blast and while still in the cabinet, give each screw a couple of turns inward and that will expose the area covered by the metal strip. Don't forget the bottom end.
3 For 3/8 inch and larger bolts, hold by hand.
4 Use metal shower rings/clips for anything with a hole in it, washers, nuts, clips, springs, etc. Leave them on the rings for phosphating, remove for zinc plating. (See picture.)
5 For smaller parts (like 6-32X3/8 screws), use a homemade container made from metal screen with some heavier mesh backing. It may not last long so be careful. TP has a "Bolt Basket" that works but real small items tend to fly out. For one or two items, try a small electrical alligator clip about two or three inches long. Turn parts around to finish. 
6 For phosphating, do not touch cleaned parts without latex (or other types) gloves.
7 For zinc plating, you can handle everything sparingly. My plater cleans everything I send to him in an acid bath to remove any residual oil like from your hands prior to any other steps.

Sources:
-TP Tools & Equipment www.tptools.com
  Bead blasting cabinets, blasting media, restoration tools, paint
- Eastwood www.eastwood.com
  Bead blasting cabinets, blasting media, restoration tools, paint, vibratory tumblers, chemicals

[jwc66k]

Phosphating -
- (finally) -
Procedure 
Note: Don't phosphate anything that is greasy or has not been bead blasted. I've found that bead blasted items can be done a couple of days in advance and still come out OK as long as they are kept dry..
Actual steps: metal blackening (if required); phosphating; rinse; dry; oil.
1 Heat water in a large enough pot to provide more than you need as you may need to top off phosphating pan as the water boils off. My large pan takes 2 1/2 gallons so I heat 3 to 3 1/2 gallons. I usually do this on my kitchen cooktop in a big clean pot. The poacher is about 2 1/4 gallons full.
2 Get all equipment ready: propane tank, propane stove, stainless steel pan for phosphating, stainless steel pan for metal blackening, stainless steel perforated strainers (one for parts from metal blackening to phosphating pan, one for pan to rinse water), stainless hooks, Pyrex glass measuring cup, thermometer, stopwatch, drying towels, rinse water pan and water, drying hooks (coat hangers cut and bent), phosphoric acid concentrate, metal blackening concentrate, oil, oil bath table covered with newspapers, evaporation bucket, baking soda.
3 When the water is hot, pour into phosphating pan on propane stove, light stove, measure phosphoric acid concentrate. I use 1 to 3 ounces of concentrate per gallon of water, usually starting at a small ratio.
4 When the water in the tank is boiling you are ready to "cook" parts. Use the thermometer to verify the temperature. If the temperature drops below 180F, stop and allow to temperature rise to boiling (or at least 200F). This is important. I use a wooden cover on the pan while heating.   
5 Start with items that do not require the blackening step or items that should have a natural steel look. Do items that need to be blackened last. The phosphating tank will become "contaminated" with the blackening solution items if you do them first.
6 Timing:
- Natural looking steel - two to three minutes in the phosphating bath. 
- Large bolts - four to six minutes in the phosphating bath. 
- Small bolts, nuts, washers and screws - one to two minutes in the metal blackening solution and then eight to ten minutes in the phosphating bath. Any more than ten minutes may leave crystals on the items' surface.
- Dip in rinse water for 15 to 20 seconds.
- Air dry until no trace of water is seen.
7 Do small batches, a single item up to maybe 20 screws per batch. The most items I've "cooked" in one afternoon session were about 400, mostly screws, bolts and nuts. Don't touch items with bare hands, use a shop towel or vinyl gloves. Stir items in pan as bubbles will form and stirring will allow bubbles to escape. Large items (hood hinges) need to be turned a couple of times for the same reason. Long items will require a fish poacher and may require lifting out "cooked" end and dipping the other end in swapping ends about every 30 to 45 seconds for three or four minutes to get an even finish.
8 When item have "cooked" for enough time, scoop out and rinse.
9 Place rinsed items on hooks or on drying towels.
10 When items are dry, oil. I found WD-40 works very well. SAE 20 works but can get expensive.
11 When you are done, allow the phosphating bath to cool. Pour leftovers into a HDPE plastic bucket and add a cup of baking soda per gallon. This should neutralize the acid. Allow water to evaporate then scrape out residue or toss the entire bucket.
12 Clean metal blackening pan, phosphating pan and tools in the rinse water. The metal blackening pan will probably turn black but don't be concerned. The grey-white residue in the phosphating pans will come out if lightly bead blasted. Do not use baking soda or laundry soap to clean pans or tools as they might have residual alkali that will slow or stop the acid from working the next time you use them. 

Safety
The acid baths are diluted enough that if you get splashed, soap and water will neutralize them. This does not apply to the concentrates. Use the borax to neutralize spills.
It is hot water, so be careful.
Keep kids and animals away. Wives or girlfriends are encouraged to bring adult beverages while working.
Jim

[jwc66k]

Phosphating

Tips and Tricks
I found that small items rolled off the strainer so I put a couple of stainless steel screws and nuts at the handle end to keep them in the strainer.
If I have more small screws or bolts to do, I'll save some phosphating bath in a covered stainless steel sauce pan for use later (like the next day).
Tie rod ends and center links, items with a ball stud. Remove rubber cover from ball stud and clean the item with a solvent. Scrape, dab or whatever you need to do to remove as much grease from the ball stud as possible. Clean with a solvent again and when dry, using Permatex Ultra Blue No Leak Silicone Gasket sealant (the blue stuff), seal the ball stud. Use a lot. Allow sealant to dry at least three weeks. Bead blast item being careful to not disturb sealant. As most of these items are natural and some are longer than the rectangle pan, use the poacher for a short cooking time. Cook, rinse, air dry and oil per steps above. After a couple of days, remove the sealant using a razor blade, wire brush and/or wire wheel. Set the item in the hot sun with ball stud up so heated grease is forced out along with air bubbles. Rotate the ball stud to facilitate bubbles getting out of the gap. What also may come out is rusty crud. Add heavy oil, 20W or 30W, to the gap around the ball stud. When the item cools off at night the oil will be drawn in. Don’t leave the item out in any rain. Do this daily for a couple of weeks until the rusty crud stops coming out. The entire process may take over a month. Remember, a NOS center link is over $100.00 and NOS tie rod ends are over $40.00, if you can find them.
Thanks goes to Rich Ciaffredo, a MCA Gold Card Judge, who got me started phosphating a long time ago, and to Charles Turner, a MCA Gold Card Judge, who gave me some critical tips.
Samples:
1 and 2 - Rear bumper bolts.
3 thru 8 - Fender and other 5/16 bolts
Special tools:
9 - The tumbler with strainer screen.
10 thru 12 - Something I made from a dip basket, funnel and a ABS pipe coupling (it fit, that's why), assembled, and with a blasting nozzle inserted into the funnel. You place small parts in the basket, assemble it and hold it up side down so the glass beads blasting up cleans and gravity returns the parts to the narrow end. After about 3 or 4 minutes check the results. Repeat as necessary. Remember, I was going for m inimum effort on a lot of items.
13 - A TP blast basket in the back, and a basket I made from a small dip basket, tin can and a clamp. I wore it out.
Jim

[jwc66k]

Some more samples:
1 - Hood hinges and springs. I did these about 4 years ago and the hinges are too dark. The springs are OK, but I will do the hinges over but lighter in shade.
2 - Center link. I did these the way I described in the Tips and Tricks section. I did four in this lot, one went on my "K" car, the other on a 66 GT-350.
3 - Strut rods. These are the pair from my "K" car, I had another set ready to go. The center link and strut rods are lighter in color because of less time in the acid bath.
Jim

[Pete Bush]

Thanks, Jim. I've really been enjoying this series of posts. It's been very educational. I might even try tackling some small stuff to experiment with. 

[Murf]

Jim, I have always wondered if using Evapor-Rust rather than water in a vibratory parts cleaner such as you described along with the green triangle media would hasten the cleaning  process or make the job easier and better.  Posed this question some time ago but no response so maybe it is just a silly notion.  Anyone attempted this?  Enjoy reading these posts greatly.  Normally use an outside propane  BBQ grille for heating the phosphating solution since it is handy and has four burners to heat the pan for hood hinges and other larger items.  Thanks for sharing your methods.

[jwc66k]

John,
  It's the warning message on Evaporust that bothers me. The chemicals in Evaporust strip off everything, which is what you want, but you must put on a protective coating within two weeks or the part "rusts". That's what stopped me in doing rear springs, It was, "What's the next step?" I fooled around with a few degreasers until I spotted TSP on a shelf and tried it. The TSP and green pyramids in the Eastwood vibrator removed that last bit of oil/grease/dirt and left an item clean enough for the next step. I'll take a picture tomorrow of some items ready to be bead blasted and then clear zinc plated. They spent about four hours in the vibrator then air dried. They are almost usable at that stage.
Jim

[CharlesTurner]

Evaporust cleans the parts really nice and speeds up the blasting process.  But, I would never phosphate parts that have only been soaked in evaporust.  I would always either lightly bead blast or use an acid wash.