We have a lot of experience making all kinds of dies as well as pressing pellets so feel free to send us questions and we'll try our best to answer them over email (firstname.lastname@example.org).
Do you make custom dies? Yes we do, just send an email to email@example.com or submit a quotation form with you requirements. Custom dies take a fair amount of machine time and man hours however we try to keep them as cost effective as possible. Custom dies start at around $400 and lead time is around 4 weeks. You can also send us your own design / CAD drawing or sketch on a napkin.
How long does it take for you to ship out after purchase? Most of the common die sizes are in stock in both our US and European warehouses and we can have in the post within 24 hours. Shipping is offered free and tracked across USA and Europe and soon in other locations and typically takes 2-3 days. We also offer a 1-day and a 2-day shipping options which is a paid option. If you place the order in the morning, we will try to get to the courier same day however please allow for up to 24 hours. If you need something else which is not listed, send us an email and we may be able to organise special shipping.
What is the max load for my die? You can find the max recommended load on the individual product page. The steel we use has a very high yield strength of over 80,000 psi or 550 MPa. We recommend a 50 % safety margin, loads for each die set should be carefully considered before using the die to ensure safe operation. This is of particular concern with the smaller ID dies where you can reach the yield strength of the steel with a few pumps of the hydraulic press. Do note that using high pressing force does not guarantee a denser pellet. If you press too hard, you will most likely surpass the fracture stress of the compact well before you reach the yield stress of the material. The stress in your pellet will concentrate at the top side of your pellet and you will likely see cracking or "capping" at the top of your powder compact.
Do I need the prepare the die set in any way? We store our dies with a water resistant lubricant. When you get it, just give it a good clean with detergent before use. If you are storing your die for a long time or it will be exposed to moisture or humidity then you can simply spray with WD-40 or a similar product before storing.
Do you sell spares? Sure, just send us an email with your needs.
Do I need to use lubricants or binders? You do not need to lubricate your die before use for most materials nor do you have to use binders. Some people like to use a small amount on lubricant on the walls of the die as this is where there is highest friction during pressing and release which can lead to cracking. Likewise, some applications and materials use binders as common processing protocol. Both lubricants and binders can be burned out afterward when sintering above 700 C leaving behind minimal residual residue (carbon).
Will my die rust? The best steels high strength, high hardness steels for making dies are not stainless (sorry). If you don't dry it after washing or store it wet - yes it will rust. Don't worry it happens - the good news is that it should be easy to clean off. If you are storing your die for a long time or it will be exposed to moisture or humidity then you can simply spray with WD-40 or a similar product. If you so want us to make a custom die in stainless, we can do it - just send us a message.
Do you have some advice for making good pellets?
There is a lot to say here...
Number 1 - obviously - press safely, if unsure ask someone with experience. You are able to put a lot of force through your die with a hydraulic press. Think about the force you want to apply beforehand, do not exceed the force for the die you are using, wear safety googles with side shields, use a guard between you and the press, keep other items off the press table so they don't get caught, make sure everything is inserted correctly and well located before pressing, if the die is overfilled with powder before pressing, the plunger will not locate properly.
Always clean your die before use - this will not only stop contamination but make the die work better, with less friction.
Higher force is not necessarily better - if you find your pellet is cracking then you should consider using less force before using more force.
If you are having trouble with a certain material - don't worry we have all been there. Consider drying before pressing changing the grain size your materials before pressing (more grinding), tapping with a small rubber mallet after assembly and before pressing (helps the powder move around, reorganise and settle before pressing), you can also try using lubricants or binders to help get your pellet out.
If you need a higher density, a more rigid compact for further handling or better surface contact between materials then consider using cold isostatic pressing (CIP) after making your pellet. Cold Isostatic Presses are available in a lot of material science departments, available through 3rd party service companies (for larger parts) or you can buy a small CIP die which fits inside a normal hydraulic lab press - for smaller discs - this is normally a good and cost effect option. We can make these too so send us an email to firstname.lastname@example.org if you are interested.