Source for ABS and a Noob Needs Help

[Cartierusm]

Ok so I just started to ponder doing some IJ molding for the binding around the head of my guitars. Seems fairly simple to me, as I can fabricate machines no problem. But i've never done it before so maybe you guys can let me know if I've got the point.

1. Make a mold out of aluminum. The part I'm making will just be 1/16" wide and .25" Deep and will just be a simple channel with the curves of the head. I will just mill it and then put a lid of aluminum on top of that with registration pins.

2. Load the material into a heater chamber, once melted have some sort of plunger or ram to force the heated plastic into the mold.

so I guess my questions are can I use any type of aluminum for the mold?
Do I need to spray or brush on a release agent on the mold each time?
Do I need to have a vent hole at the end of the part and how large of a vent hole should I have or does it not matter?
My guitar vendors describe the plastic binding as ABS, where should I go for that or can I just remelt the abs binding I have as it's already the right color?

Thanks for the help, as always I will continute to read past posts and google until my hands fall off.

[navnav2006]

I dont know what is your final outcome. But if I was you i would defienetly made a mold out of steel instead of aluminium.

Though there is nothing technically wrong since melting point is above 650C.
But never heard of making aluminium mold for plastics.

May be give a Try.

[mc_n_g]

For onesy-twosy things you can get away with aluminum molds. Try to use 7075 if you can. Works nice and cuts cleanly without all the gumming of other aluminums (4000 series and some 6061). You can use 6061 but it can be a mess if you have not used it before for milling.
For you first adventure I would look up Dave Gingery's book on builidng a small home-made plastic injection press. It is not heavy duty and you will most likely have quite a few failures. I would learn more about what plastic injection is and how it works to answer some of your questions. Look into materials after you understand the process first. Every material has a different set of factors involved.
I run 7075 and 2024 aluminum all the time on short runs in injection machines from 4-15 tons without any problems.

[Cartierusm]

Thanks for what I'm doing now that i've got it down it just takes a couple of minutes to use a heat gun to bend the plastic around the form. Thanks anyway for the help.

[ckirchen]

There are plenty of molds out there that are made out of aluminum.

One of my customers has a "prototype" mold that has run 500,000 parts made of 40% glass-filled nylon. Sure the gates wore out and had to be replaced, but that's to be expected with such an abrasive material and after so many parts. The rest of the mold shows minimal wear.

I had lunch today with a customer that runs a large aluminum mold (1" x 10" x 30" part); it still looks brand new after 65,000 parts.

There are specific grades of tool aluminum, but I have used both 7075 and 6061 in the past with good results. Use flood coolant and you won't have problems with gumming up the cutters.

Chris Kirchen

[Michael.lee]

Chris Kirchen,

Injection molding plastic products have the similar concept as what you thought now. If you need quality ABS components for your guitars, my suggestion,

1. If you only need a few, you can consider to create them via prototypes ;
2. If you need many, you can consider to get a mold for molding these, the way you done is too simple, and I am sure that the quality is bad ;

Concerning of product design, protoype or mold, if you need assistance, please contact me directly.

Cheers,
Michael.L