squigster Posted April 14, 2018 Report Share Posted April 14, 2018 Hi All, I have two of the Ultramolds smaller shooting star machines and one of them I am having issues with air getting into the baits. I took the injector apart and cleaned it, I removed the nut, plate and injector port from the machine. I can hear air getting sucked in when I draw the injector around the nut. I put two o-rings on the injector instead of one and it solved the problem temporarily until the additional O ring broke from the heat or something else. I added another one and the same thing happened. I tried tightening the nut and tightening the set screws but to no avail. The one thing that I do notice is that the bottom port of the two hole port slowly leaks when running. Not a lot but some so I am perplexed on what is wrong. I have cleaned them all and inspected them but still same issue. This is making me crazy as I get about a 50% success rate on baits. Either they have air pockets or are incomplete. I have tried shooting the molds on an angle and lowering temperatures to around 305 - 310 but still same problem. Something is not sealing and i can hear it when drawing from the machine. I readjusted the position of the support bracket also. I am tired of spending half my time fighting this thing. I have had it for a while and clean it about once every two months so I am perplexed at what might be wrong. Any thoughts or suggestions would be greatly appreciated. Thank you! Quote Link to comment Share on other sites More sharing options...
Cub48 Posted April 15, 2018 Report Share Posted April 15, 2018 I clean my injector every batch of plastisol. When i first got my system i did not clean between and i started having the same issues. Here is what i done to fix cleaned injector my system is bolted to table when i am pulling plastic in the injector i push in on injector while i draw in the plastic and also draw slow i had a problem once by pulling too fast. I shoot with system at 296 F. I did buy a second injector in case i started having problems i could switch injector. Also i bought the injector heater i love it heat the injector better than the system. let me know if i can help u anyway Cub48 Quote Link to comment Share on other sites More sharing options...
squigster Posted April 15, 2018 Author Report Share Posted April 15, 2018 Thanks Cub48 Im losing my mind with this, I loosened the set screws and pulled that out. Took off the nut then the 2 hole port. Cleaned them all making sure not to scratch the port and then put the two hole port back in put the bracket back on and spun the nut until it was tight then I got a wrench and tightened up the nut and tightened the set screws. The set screws seem far away from the body of the machine like the nut wasnt tightened enough. Anything here i missed? Appreciate the help. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 15, 2018 Author Report Share Posted April 15, 2018 Heres pics of them after I cleaned them again Quote Link to comment Share on other sites More sharing options...
RAZOR Jim Posted April 15, 2018 Report Share Posted April 15, 2018 Have you replaced the "O" rings in the bottom of the injector? The "O" rings that are in the bottom/tip plate that the tube seat in. I had problems with air and discovered that these "O" rings had torn. I also notice that as I locked my injector into the port/orifice that the body (tubes) would twist as I was locking in and removing. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 15, 2018 Author Report Share Posted April 15, 2018 No I have not looked at those as they are seated inside the bottom piece. I will examine them tomorrow but I do not have replacement rings if they are bad.. I see nothing on UM's site for spare parts so Ill have to call Monday I guess. I am wondering if the tubes that go in the machine are worn and also the orifice ports themselves. Look at the pics closer. It looks like wear. I have not shot all that much so hopefully this isnt going to be something I am dealing with all the time. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 15, 2018 Author Report Share Posted April 15, 2018 (edited) Also any suggestions on cleaning the injectors quickly? The one rod has rusted into the bottom plate and its pain trying to get the injector apart without beating it with something after taking the nuts off the rods. Edited April 15, 2018 by squigster Quote Link to comment Share on other sites More sharing options...
RAZOR Jim Posted April 15, 2018 Report Share Posted April 15, 2018 I don't clean the injector often. When I finish shooting the plastic, I evacuate the injector, run the plungers up and down a complete more times. I store the injector with the plungers half way down, not all the way down. When I take my injector a part, I remove the 2 nuts at the top. I don't ever recall removing the bolt shafts that screw into the base. You have to call Ultra Molds to get the replacement gaskets. I also had problems with the nipples/tips on the base plate. Apparently I was very careless inserting and removing the injector from the orifice and damaged one of the nipples/tips and had problems with injecting. Quote Link to comment Share on other sites More sharing options...
DaveMc1 Posted April 15, 2018 Report Share Posted April 15, 2018 When you over tighten the nut for the valve you also make it so the o-ring on the tip of the injector doesn't seat causing it to suck in air. Once you have done this you also have permanently squished the white PTFE o-ring between the nut and disc (2 holes in it). I just pulled all 3 of mine apart on both setups for the first time in several years and replaced all of the PTFE o-rings with 2 o-rings. The valve will be tight so I over tightened it a little (while it's hot) and backed it off a slight bit. All is perfect. Quote Link to comment Share on other sites More sharing options...
Painter1 Posted April 15, 2018 Report Share Posted April 15, 2018 I have, and use, this system. It appears from your pictures that you need some new parts. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 16, 2018 Author Report Share Posted April 16, 2018 Talked to Rupert 15 minutes ago and hes gonna send me some new parts. Hopefully this will resolve the issues. I do believe I may have over tightened the nuts also so maybe thats and issue as I may have damaged the seal, but when you cant get something to seal you tighten it more. I never payed attention to the seal inside the nut. I think its the plate thats an issue but we will see. Thank all of you for your help! Quote Link to comment Share on other sites More sharing options...
DaveMc1 Posted April 17, 2018 Report Share Posted April 17, 2018 10 hours ago, squigster said: Talked to Rupert 15 minutes ago and hes gonna send me some new parts. Hopefully this will resolve the issues. I do believe I may have over tightened the nuts also so maybe thats and issue as I may have damaged the seal, but when you cant get something to seal you tighten it more. I never payed attention to the seal inside the nut. I think its the plate thats an issue but we will see. Thank all of you for your help! You squished the o-ring, the disc looks fine. Like I said, I just rebuilt 2 setups (6 valves), I just added 2 o-rings, brought it up to temp, figured out how tight I needed it to be so it would seat the small tips in the disc and still seal the main external o-ring. Then I tightened the nut a 1/16 of a turn and backed it off, haven't had an issue since. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 17, 2018 Author Report Share Posted April 17, 2018 I added 2nd o-ring to injector and it immediately tears the new one. Tried it twice with adding another and same result. He thinks theyre may be burrs on the face of the orifice or inside the nut. We will see. He said to try sanding the inside of the nut to knock off burrs so I may try that. Ill let yall know. Thanks! Quote Link to comment Share on other sites More sharing options...
DaveMc1 Posted April 18, 2018 Report Share Posted April 18, 2018 16 hours ago, squigster said: I added 2nd o-ring to injector and it immediately tears the new one. Tried it twice with adding another and same result. He thinks theyre may be burrs on the face of the orifice or inside the nut. We will see. He said to try sanding the inside of the nut to knock off burrs so I may try that. Ill let yall know. Thanks! No, don't add a second o-ring to the end of the injector, I'm talking about adding a second white PTFE o-ring inside the nut for the valve. That is where the issue lies. You've pushed the nut too close to the disc, bottoming out the injector nozzle before it's o-ring can seat inside the nut. You need to space the nut out further to make a proper seal. Quote Link to comment Share on other sites More sharing options...
squigster Posted April 18, 2018 Author Report Share Posted April 18, 2018 Ok Dave I understand, If Rupert gets back to me. I will see where I can order the spare seals from. Thanks again for your help. I am getting dents in my baits now also. Im not sure if its air trapped or im not holding injector down long enough to keep pressure. I guess Ill figure it out. Thank you! Quote Link to comment Share on other sites More sharing options...
