After looking as some of the more expensive powder guns I made a couple of changes to my gun that helps me. A copper multi wire tip & powder diverter.
Attachment 162492Attachment 162493Attachment 162494Attachment 162495
Printable View
After looking as some of the more expensive powder guns I made a couple of changes to my gun that helps me. A copper multi wire tip & powder diverter.
Attachment 162492Attachment 162493Attachment 162494Attachment 162495
What does it "help" you do? What fault were you correcting?
Little more explanation, please? Your last pic shows the added 'powder diverter' with a screw-on cap in place...how does that work?
Bill
My powder spread was too large using the any of the included HF plastic tip diverters, no diverter worked better.
With my add on's my powder stream is reduced and denser. I also think the copper tip gives me a better charge as there is more contact surface as well as copper a better conductor. Its all subjective, but the powder seems to bond more even and faster.
If no one has guessed the diverter is a plastic bottle slipped over the gun barrel and taped. The cap just seals the end of the gun when not in use.
I added the wires and it does help. The step in the bottle may help with powder 'dumps'. Cap helps keep the powder dry. I used a 45 PVC pipe but no reducer or cap. Clean the wire after a while, to keep the charge going.
I take it the powder builds up faster with the added contact of the wire? I have tried moving the direction of the air that swirls the powder that seemed to help very little. Also added some airsoft bbs into the mix that seemed to help here and there one thing for sure it making sure the powder gets up into the air stream.
Thanks for added info. I've experienced much the same thing...wide spread/low powder density...no matter which tip I used. Might just get my HF gun out this afternoon and see what I can cobble together.
Bill
Just brush off the powder from the wires or blow it off with the compressor. Extra wires expose more powder stream to the static field.
Bill: You might want to start out with just the bottle, assuming you can find the right size to just slip over the barrel, and see how that works as little time and effort is involved. I am sure others will come up with better ideas. I considered cutting down a plastic funnel, but I had none the right size.
If anyone wishes to make a multi-wire tip. The thread size on my HF gun is 4-40.
Any other questions I will be happy to answer.
Pretty neat! The HF gun does need a little help getting more static to the powder. 8-)
Clean the powder off the wires frequently - powder build up on the wires reduces static.
I used a 5-Hour Energy drink bottle. It requires one wrap of duct or similar tape for a tight fit. Does a good job tightening up the powder stream
Hi Walter,
Is your bottle a #5 (Polypropylene) bottle as I would think this would also help by giving off electrons? What I am using is a #2 (Polyethylene), but looking for all the help I can get.
I always have a soft 3/4" artist brush handy when using either of my ESPC guns to brush off the powder from the busniness end. I does seem to help with the speed and qualtiy of the coating to have a clean end!
Amd I blow out the gun body each time I end my session. HF sells a 12" long air "needle" blowgun that is great for getting up inside the tubes.
Been too sick and now too busy to do any coating in the past 3+ weeks. Just now catching up on all that delayed engineering work I put off while under the weather.
banger
Has anyone given any thought to a spring inside the guns nozzle tube attached to the electrode? That would surely give it a lot more surface area to charge the powder but may build up with to much powder to fast to make it worth the effort. Just thinking out loud since I do not have the time to test it myself.
Here are a couple of pictures showing how controlled, dense and well bonded my spray pattern is also note the lack of overspray even outside without my wind shield. I didn't get these results with the out of the HF box gun before my additions.
Attachment 163723Attachment 163726
Looks good I have noticed the older my powder gets it must be sucking in moisture and its not working as well. I am going to try the improvements on my gun and see if that helps its been a real wet winter.
Check out my post "Keeping your Powder Dry", showing my very effective and inexpensive homemade in-line air dryer. Any moisture in your air supply is not good because the powder tends to cake and moisture dissipates the charge.
It looks like you soldered the additional wires on. Correct?
This is a very interesting thread, let's keep it alive! Any new stuff to add? How does this mod work for, say, automotive or motorcycle parts?
So, what gave you the idea for the 4-pronged wire thingy? And are those soldered to the rod in the gun, or are they soldered to some threaded piece that just screws on? More details please!
I got the idea of a multi tip from seeing one on a high dollar powder coating gun. It made sense that more surface area and a better conductor, copper, would transfer a better charge to the powder as it flowed through. I first started out trying the little plastic powder diverters supplied with the Harbor Freight gun , but quickly found they spread the powder out. I felt like what was needed was a tighter flow, not larger. I went through my box of funnels because what I wanted was to compact the air stream, like a funnel. I couldn't find anything on hand then I started looking in my box of jars and found a small plastic bottle. When I cut the bottom of the bottle off it fit almost perfectly over the HF gun nozzle, secured with a wrap of tape. It reduced the width the powder flow and allowed me to direct all the powder to a much smaller area, just what I wanted.
The multi-wire tip I made from a copper welding tip for a MIG welder. I shortened the length of the tip some, as it was a little longer than needed. I drilled out the center of the MIG tip with a #4 drill bit so I could later thread the tip. I drilled two 1/16" holes perpendicular to each other completely through the barrel of the tip and inserted two short pieces of copper wire into the holes, then bent the copper wire on all sides so the wire would lay flat against the against the outside of the MIG tip and the 4 wires pointed to an end of the tip and extended a little past the end. I soldered the the 4 strands of wire to the outside of the MIG tip. Then I redrilled the center of the MIG tip with the #4 drill to cut through the copper wire I had inserted through the drilled holes in the sides. I tapped the center hole using a 4-40 tap to cut the threads and cleaned the tip with a short soak in 1 to 1 mix of Hydrogen Peroxide and white vinegar and a little a little wire brush. Now the tip just screws onto the existing threaded shaft of the HF gun and my bottle diverter slides over and covers the tip. I have found this to be a big improvement over what I had to begin with; if your goal is a tight dense spray pattern.
You lost me here...according to my references a 4-40 tap uses a #43 tap drill bit not a #4. Is that a typo, or am I missing something here?Quote:
Then I redrilled the center of the MIG tip with the #4 drill to cut through the copper wire I had inserted through the drilled holes in the sides. I tapped the center hole using a 4-40 tap to cut the threads...
Yes, it is a typo, should be #43 drill bit for 4-40 thread, not #4. Thanks for catching it.
Don't know what it is, but the threads on my HF gun definitely AREN'T 4-40. Metric doesn't seem to work either. So I may forego the prong thingie, and just go with the bottle extension.
Been searching for this thread for weeks. Giving it a bump .
Good info, thanks.
Probably not needed as most are probably aware, but making sure you compressor air is as dry as you can get it makes a huge difference. The small inline plastic filter that comes with the gun is next to worthless for drying the air sufficiently.
I have a lot of trouble in my area with the moisture too. Which filter do you use?
I originally made a simple coalescing filter out of pipe and stainless scrubbing pads that then fed the air into desiccant. This filter was set up to dry the air as it came out of the compressor tank.
I have just purchased a new 60 gallon compressor that delivers 18 CF a minute, so I am presently working on a system that will dry the air before it goes into the tank. I have several ideas that I am playing around with involvingcoalescing filters and a refrigerated dryer. I would have had it finished by now, but my TIG welder had to go in for repairs and Everlast Welders is taking their own sweet time about getting the unit turned around.
Living on the Gulf Coast our humidity is almost always very high unless we have a cold front move in.
I've seen several other forums mention that they changed the hopper to allow it to be connected and hang down instead for up and over the gun but none of the sites have pics of what they did. Anybody done this here.
I've read that also.
I don't see how that would work. The whole point of the gun is to make a "tornado" of powder that is stirred up by the incoming nozzle at the bottom (which is buried in powder) and get picked up as it rises by the outgoing hooked tube at the top and then goes whisking on down the barrel of the ESPC gun and then gets its charge from the electrode(s) as it passes. If it were inverted, there would be no powder between the short incoming nozzle and the opening of the hooked tube as the air goes out. But I would definitely be up for taking a look at any other redesign of such before I said it didn't work.
If it helped with too much powder being fed to the HF gun then it might be an improvement. In comparison the HF gun comes up second to my Eastwood Dual Voltage Gun anyway, so I will probably never use my HF again and only keep it as a backup. The Eastwood gun does have a bottom feed and the powder flows so much better without any modification. One of the big pluses are the extra powder bottles for the Eastwood are cheap, so a bottle for each color is possible.
Now a Sticky to never be read again lol well we see.