Humidity

[Gohon]

What is the affect of humidity with the shake and bake method? I've always powder coated during the winter months when stuck indoors. However, because the temperature was so high outside I decided to powder coat some casts to pass the time. Problem is I can't get the powder to stick no matter what color used or container used. Right now the humidity is at 55% and averages 60%-75% here where I'm at. Yes it is miserable. I'm using Columbia powder which has never given me a problem in the past. Only thing I can think of that is causing the problem is humidity. Appreciate any help given.

BTW...I do have a Harbor Freight spray gun but would prefer not to have to set that thing up and deal with the mess.

[Smoke4320]

Are you using black 25 gram Airsoft bb's

If not I would highly suggest that you do and before putting in powder and bullets (during hi humidity days) swirl the bbs for about 20-30 seconds in the #5 triangle marked tub
it will help build static .. then add powder and bullets .. proceed as normal then

[Gohon]

Smoke, I am using the black 25 gram airsoft BB's and the container is a #5 cool whip. Also tried a #5 ziplock screw on lid container but a no go. Only thing different than what you said was I did not swirl the BB's first before adding powder and casts but I've never done that in the past either. Been using this method for a couple years and never had this problem before.

[Smoke4320]

Try it once if it does not work all your out is a little time ..
The problem is the Hi humidity is killing the static so you have to do things to increase the static .. The above is one way ..
Some people say sliding the plastic tub back and forth on carpet woks for them .. a couple people even say they add Styrofoam peanuts first with the bbs ...swirl then remove Styrofoam BEFORE adding powder and bullets

[Smk SHoe]

I have to shake the living He77 out of them when the humidity is high ( NC right now is around the 75-85% range). will try shaking before adding bullets and maybe the peanuts to help build a static charge

[Bama]

Do you have access to a dehumidifier? In upset conditions (high humidity) I set the bowl next to the outlet of the dehumidifier. After an hour or so it is dry and it seems to add a significant amount of charge. Heating of bullets also get the surface moisture off, you don't have to heat over 160'F, just enough to remove surface moisture.

[farmerjim]

I do the shake and bake in an air conditioned room in my barn in the summer. No problem as the humidity is low in that room. 90% + outside.

[Gohon]

Appreciate the suggestions but no joy so far. Guess I'll have to break out the old spray gun. I am in a air conditioned room so that isn't a factor. I had heard the humidity played a factor in success or failure but just hadn't experienced it to date.

[MyFlatline]

Try a different container, even if it say's #5. I live in Central Florida, it doesn't get any more humid than here. When I first started coating, I sprayed everything, HF powder did pretty good, red will stick to anything. When I decided to try tumbling, they wouldn't coat. I tried some different powders online, still had issues, changed tubs, and wha la. I coated some yesterday, 90° and 85% humidity. they did fine.

[Gohon]

I coated some yesterday, 90° and 85% humidity. they did fine.

What is the container you used yesterday? I've tried the cool whip container which I've always used and also a ziplock screw on lid container. Seems odd something that worked well before all of a sudden wouldn't.

Added: Just tried two additional containers, One made by Glad and one made by Rubbermaid. Both were a no go.

[ChuckO]

I have found that storing the container, ASBB's and powder in an air-tight box with a couple of desiccant packs works well. I get good coverage after a day's storage to dry things out initially. I simply place each color's materials in a separate ammo can with the desiccant when I'm finished for the day. I get poor coverage if I leave a container out overnight while a similar container stored in the dry box will work.

[retrobass]

http://i.imgur.com/DuhlLYz.jpg

Here's some coated in unreal GA heat and humidity yesterday. I coated them with Smokes clear in my air conditioned reloading room, then brought out in batches of 100 to toast. Powder had NO trouble sticking.

[Walter Laich]

I've taken my powder storage containers inside in the a/c for a couple of days when I suspect they have gotten too much humidity. Seems to work.

2nd the idea of really have to shake the tumbling containers hard. Almost like you're trying to break them with the bullets inside. That solved my problem of a month or so back. Humidity along the Texas Gulf Coast rivals all the locations mentioned in this thread

[MyFlatline]

What is the container you used yesterday? I've tried the cool whip container which I've always used and also a ziplock screw on lid container. Seems odd something that worked well before all of a sudden wouldn't.

Added: Just tried two additional containers, One made by Glad and one made by Rubbermaid. Both were a no go.
the country crock fake butter containers have been working the best

[reddog81]

I have switched to a PVC pipe with some cheap "test ends" from Home Depot. It doesn't seem to be as sensitive to the humidity. AC makes a big difference. I haven't had to turn on my dehumidifier yet.

[Gohon]

As mentioned before the powder I'm presently using is Columbia Coatings RAL powder which has worked fine in the past. I have six different colors of that powder. The color I have been trying to use is the Brown Beige I use for 45 Colt loads. I am doing this in a air conditioned space and the powder is stored in the same space. Heating the bullets, shaking the heck out of them, different containers...all were a no go.

I live right next to a large lake and the humidity is always 20% higher than the weather guessers say so I'm right at 80% everyday this time of year. Well, I tried two different colors of the Columbia powder, Jet Black and Window Gray. The Jet black sticks perfectly and the Window Gray sticks but a little thin. Apparently some of the colors of this brand of powder is affected by humidity conditions much like the Harbor Freight powder. Dry low humidity, all of it works with the shake and bake procedure but high humidity, only some colors work well. Doesn't sound logical but that's what I've run into.

I do have a couple bags of Eastwood Powder on the way so I'll see if that works better.

[MyFlatline]

At least you have a idea on why, now. I ordered in a bunch of colors from Powder by the pound, all have done very good. When I order again, I may try some of Smoaks powder. 15 pounds of powder goes a long ways tho when tumbling.

Again, glad you got it figured out.

[rsrocket1]

Try going indoors into your air conditioned house. Do the shake in the bathroom where any powder can be cleaned up. You can shake in there and stack the boolits onto the tray, take it out to the backyard for the baking. It's unlikely that the coating will fall off in that short time period. What do you have to lose, 1/2 teaspoon of powder?

Our summer has had the humidity around 10% or less. The trouble is it's too hot @ 105-110 around 5 pm for many days. We just had a cool snap of 95 for the past 2 days.

[DEC505]

Gohon, When I got home this afternoon,thought I would try to coat some boolits. Being in central Florida we are in the middle of a tropical storm. My shop is not equipped with a/c or heat.

Using Smoke's powder I got good even coverage and they baked out perfect. I say all this to think that maybe humidity may not be your problem, any chance that your boolits may be contaminated with hand oil, or mold release agent from your mold ?

Hears hoping you can get this figured out. Derrell

[P Flados]

I have done a LOT of high humidity S&B. I am thinking that part of the puzzle is boolit temperature.

When I have taken boolits from my A/C cooled loading area outdoors for S&B during high humidity, I am thinking that minute amounts of condensate may be "killing" the static.

When I have used boolits that were stored outside, the humidity seems to be much less of an issue.

I remember "prewarming" some booits to 120 - 140 °F once. I recall getting quick & easy coverage.

[Dragonheart]

I live in the Gulf Coast. High humidity is not only a problem with shake & bake it is a problem spraying also if you have not taken steps to dry the air going into your compressor. The first step is keeping your powders stored in airtight containers. I have stored my powder in a freezer for years with no problems, also my garage & workshop are air conditioned. Before I had AC I had good coating days and bad coating days due to high humidity. Preheating helps a lot on the bad days. When I coat items other than bullets I usually preheat the object to 400 degrees then spray. The powder melts and flows on contact letting you see the result, then cure the object as normal.