pearcetopher
12-22-2013, 07:51 PM
After casting for about a year my Lee pro 4-20 melter has fallen victim to a rapid drip. So fast I could almost use it to pour 6 cavity molds with, I was tired of getting splatter on my clothing so I thought I would try to clean it. However nothing would seem to work. I tried jamming a 1/16 drill bit in the spout, I tried turning the spout nozzle with a screwdriver, I tried praying to Allah, I tried heating up the spout on max, I tried blowing compressed air through it, I tried pouring water through it but nothing seemed to unclog my issue.
I decided to do a full clean,
I put on my P100 respirator and eye protection, (the eye protection needs to seal against your face as the dust WILL get in your eyes).
I then loosened the nozzle flow adjust screw and backed it out until I felt tension. Then I used a flat head screwdriver to pry the Nozzle Rod slot away from the adjusting screw lip so I could pull the nozzle directiy out up and through its hole on the nozzle screw bracket.
After the nozzle rod was seperated I instantly noticed that gunk buildup on the end of the rod. This gunk is what was causing the leak. I used my dremel brass brush (any brass brush will work mounted on any tool) to clean first the nozzle end of the rod and then the entire rod. The important thing to remember here is to try not and score up the end of the rod or it will not seal properly. DO NOT GOUGE IT or you will be buying a new one. When I was done the needle end of the rod was shiny and smooth, indicating it would seal well against the seat in the bottom of the melter. Very similar to carburetor needle and seats which is why I am writing this how to. This is what it needs to look like
91316
91317
After the rod is cleaned you will need to clean the seat it sits in. For this I decided to use an old small 22 calibre bore brush and run it into the seat. You will need to used a soft metal such as brass or bronze to do this or you will score up the seat, and it will not seal, and you will be mad. After you have ran the bore brush inside the seat a bunch of times it will be relatively clean. You can tell by looking through the top end and seeing a nice circular point of light. Indicating it is perfectly clean inside.
91318
Next is to flip the melter upside down, and run a dremel brass brush or any brass brush against the bottom pour spout of the melter, so that it is clean and has no more junk in it. It should look like this;
91319
Next is to take a 1/16 drill bit and insert it with your hand into the pour spout of the melter (from the bottom). DO NOT USE A POWER TOOL FOR THIS STEP .Twist the bit back and forth until it moves freely inside and is no longer catching on anything inside the spout.
Next step is to take a small amount of water and pour it inside the melter. A frothy yellow mix of junk should come out the bottom in a nice cylindrical pour indicating the spout is perfectly clean. If the water is not coming out perfectly straight down then junk has accumulated again and needs to have the drill bit fed back in the pour spout to unclog whatever has fallen in.
After the water is coming out clear, the only thing you need to do is take several Q-tips and insert them into the top end of the seat to grab the rest of the junk and clean out the last little bit of stuff that has accumulated in there.
As a final step make sure that there is still a perfect cirular beam of light coming through the seat before you put everything back together. Then insert nozzle rod back into seat, pry away from adjusting screw until the nozzle notch matches up with the adjusting screw edge and tighten down adjusting screw until you begin to encounter resistance. DO NOT OVER TIGHTEN OUR YOU WILL WARP THE NOZZLE ROD AND OR SEAT SURFACE. Then back the screw out three complete turns.
She will not drip anymore,
I decided to do a full clean,
I put on my P100 respirator and eye protection, (the eye protection needs to seal against your face as the dust WILL get in your eyes).
I then loosened the nozzle flow adjust screw and backed it out until I felt tension. Then I used a flat head screwdriver to pry the Nozzle Rod slot away from the adjusting screw lip so I could pull the nozzle directiy out up and through its hole on the nozzle screw bracket.
After the nozzle rod was seperated I instantly noticed that gunk buildup on the end of the rod. This gunk is what was causing the leak. I used my dremel brass brush (any brass brush will work mounted on any tool) to clean first the nozzle end of the rod and then the entire rod. The important thing to remember here is to try not and score up the end of the rod or it will not seal properly. DO NOT GOUGE IT or you will be buying a new one. When I was done the needle end of the rod was shiny and smooth, indicating it would seal well against the seat in the bottom of the melter. Very similar to carburetor needle and seats which is why I am writing this how to. This is what it needs to look like
91316
91317
After the rod is cleaned you will need to clean the seat it sits in. For this I decided to use an old small 22 calibre bore brush and run it into the seat. You will need to used a soft metal such as brass or bronze to do this or you will score up the seat, and it will not seal, and you will be mad. After you have ran the bore brush inside the seat a bunch of times it will be relatively clean. You can tell by looking through the top end and seeing a nice circular point of light. Indicating it is perfectly clean inside.
91318
Next is to flip the melter upside down, and run a dremel brass brush or any brass brush against the bottom pour spout of the melter, so that it is clean and has no more junk in it. It should look like this;
91319
Next is to take a 1/16 drill bit and insert it with your hand into the pour spout of the melter (from the bottom). DO NOT USE A POWER TOOL FOR THIS STEP .Twist the bit back and forth until it moves freely inside and is no longer catching on anything inside the spout.
Next step is to take a small amount of water and pour it inside the melter. A frothy yellow mix of junk should come out the bottom in a nice cylindrical pour indicating the spout is perfectly clean. If the water is not coming out perfectly straight down then junk has accumulated again and needs to have the drill bit fed back in the pour spout to unclog whatever has fallen in.
After the water is coming out clear, the only thing you need to do is take several Q-tips and insert them into the top end of the seat to grab the rest of the junk and clean out the last little bit of stuff that has accumulated in there.
As a final step make sure that there is still a perfect cirular beam of light coming through the seat before you put everything back together. Then insert nozzle rod back into seat, pry away from adjusting screw until the nozzle notch matches up with the adjusting screw edge and tighten down adjusting screw until you begin to encounter resistance. DO NOT OVER TIGHTEN OUR YOU WILL WARP THE NOZZLE ROD AND OR SEAT SURFACE. Then back the screw out three complete turns.
She will not drip anymore,