Thread: Just injected my first molds have a few questions please !!!!

Hi guys
This my first try at injecting. Don't go by the color as this is just a bunch of old plastic mixed up. Also this is my homemade injector. I have a couple questions on improving it a little. I had a few told me i would be better to spend the 50.00. I have $0.00 in this one with about an hour of work. I think it done a good job for the first time. The improvements, What size is the tip hole in the store bought ones. Mine may be a little small. I just didn't want to get it to big to start. It worked good but wanted to clog up a little. I may taper the hole on the inside of the tip. I shot 6 molds and only lost one had a couple on the bottom the tail didn't fill. What does everyone do when they take the baits out of the molds hang them or lay them on something flat. How long do you let them cure before you oil and bag. My first shot had a dimple in a few not bad what causes this? Got to get me a better pan just looking for the right size . Used hot plate worked great. Need to make me some hand pour pots so i can do two color baits. Been looking for some metal measure cup for the hand pouring have not found them. Thanks Cub48

First of all I have only been into soft plastics for three monthe. I would advise you to read the saftey tips at the top of this forum. I would also advise you to spend the money and get a quality hand injector. Spend the $50.00 because your hospital bille will be more than that if yours malfunctions. I would also advise you to forget about using a metal measuring cup. The hot plastic will heat that up very quickly and again you are risking a severe burn. Go to the thrift store or flea market and get yourself a pyrex measuring cup.

When I take my lures out of a mold I just lay them on a sheet of aluminum foil for about three minutes.

You say when you shoot your lures you get dimples, clogging up the hot plastic etc. Get a good injector!

I also will put worm oil and also anise oil into the hot plastic as well as glitters made for soft plastic. Do not use any other glitter. I will also put a few drops of worm oil in the bag to keep them appetizing. I do not sell mine. I just make them for myself. Hope that helps some.

be careful about using homemade injectors just make sure that they are safe Mike is 100% right on when he said I cannot add any more to it he has said it. I definitely like the color of your baby Shad stingers.

Thanks guys I did do my reading i have bought some colors and anise worm oil. This batch was just some old plastic i had around for test purpose. But i believe it would catch a fish. LOL. Do you mix the oil in the hot plastic, does this not make the plastic softer. Also the homemade injector is all metal the piston is metal with a oring the tip is metal and has a screw to hold it in place. It fits tight in the tube. It can be taken completely apart to clean. it was designed for presure in its former life. It worked great i just wanted to know the hole size that works best in the tip. My next step is to order some glitter and a few more colors. On the pans i like the hot plate as it will keep the plastic hot between shots. I have been looking for a small sauce pan but have not found what i want. I am looking for one about 3 or 4 inches across and 5" deep or so. I used a stainless bowl last night its ok but not what i want. The metal measure cups i have seen i though would make good hand pour pans for small batches. Like on doing 2 color baits. I am just making baits for myself and a few friends. Thank You for your input it makes it easier on us newbies Cub48

Your injector should be ok. It looks like a bike tire pump? Should work good. I would recommend a high temp oring viton is the name brand I use. they are good up to 450 deg. or so. other than that , my injector has a .156" hole it is home made and works great. good luck.

Good looking baits there. My hole is .140" in the tip. I did replace the oring. it's not a tire pump it's off a car. The only problem i had was the tip cloging a couple of times. I may taper the hole on the back a little and enlarge it to your .156" Which maybe a job in it former life it was a torque socket and it's very hard took awlile to drill thru it. How many drops of color per oz do you use just as a starting point. Say like your tails on your baits. thanks Cub48

be careful leaving the plastic on the hotplate, soon as it gets to 350 pull it off.... plastic burns very quickly. but melts fast if still warm... i use between 5-10 drops per 4oz plastisol.. perfect sauce pans WITHOUT non stick bottom can be found at walmart, a silver bottom makes it easier to 'read' the color.... also watch clogs/pressure...again 350 plastic is dangerous...doesnt wipe off but smears the tip will cool but sometimes the plastic in the injector behind the coolwd tip will still be 350 and ready to blister your skin

Thanks for the input. I did some work on my tip. It was a socket in it's former life i filled the square hole with brass and redrill the hole. I think the square hole was holding plastic and giving it time to set. I found a pan at walmart it is a egg poach pan small it is coated but we will see how it does. I have been busy on other projects like replacing carpet in my boat and other things and have not had time to pour or inject thanks Cub48.

I have never shot my 2 plastic molds. I had one made and then made a mold myself. But my first mold was made using a 3/16 hole leading to the cavities. the mold i had made has 13 cavities and my mold has 48 i think. The injector hole size would entirely depend on your mold design. You injected plastic look good, i dont see any problems. As per your injector only you can say if its safe since you made it. Wondering if you made or modified it, at first glance i thought it looked like a pneumatic shock for like rear car windows, lol. I may have to find a bad one and cut it open. I have some tubing scraps sitting next to my dads lathe 500 miles away i will eventually get around to.

You guessed it on the injector i made. I made it out of a liftgate shock. The one i used had leaked the oil out of it. I sawed it to the length i wanted. Beveled the end of the tube. Replaced the oring on the aluminum piston. 3/4"inside bore that is super smooth. I made the tip from an old broken torque socket. It fit perfect and tight in the bore. the socket had a hole in it's side i tapped a hole in the tube and put a set screw in it to hold the tip. Only problem i have had is keeping the tip hot enought so the plastic won't cool to fast I solved that problem by pulling the plunger back and let the tip set on the hot plate when i am taking the plastic out of the mold. I have also ordered some 3/4" aluminum rod to make some tips out of I think this will help the cooling problem as it should heat up faster. I have $0.00 in this injector. The shock was free ,the socket was broken, the partsman gave me the new oring, if i add the new tip i am going to make i will have 10.00 in about 24 tips. this is my hobbie so won't count labor. P.S It can be completely taken apart and cleaned the end screws off the rod and the piston and rod will slide all the way out. Cub4