QUESTIONS TO ASK
VACUUM FORMING - Just Ask !
Vacuum Forming is a relatively simple process. Simple as it may be theoretically, at the same time it can be quite challenging to achieve good results. As I always say, "it's easy to hack but difficult to hack well". On top of that there are many nuances that present a significant learning curve. Add to that the lack of real nuts and bolts "good" information to get started and we end up with a lot of questions after the fact. So hopefully you found this before you started so you have a better chance of doing it right the first time. If you found this after the fact, it's not too late. To help you along, here's a few questions to start with before you buy or build.
QUESTIONS TO ASK:
1) Here's what I want to make ________ . Is this a good candidate for Vacuum Forming?
2) I want to make (X) many parts, (X) often @ (X) size. What would be a good set-up for this need?
3) My intentions are to become a: (hobbyist only - hobbyist w/sustainable sales - semi pro - professional ). How would that affect my choice of what to buy or build?
4) Can I buy a VF system or do I have to build one? Where do I go to find?
5) How much will it cost? What is the build skill level 1-10 if I build.
6) How much electrical power do I need for the system I want?
7) ROI & Cost Effectiveness
8) How do I make molds, what tools and materials are used?
9) How much space does this take up.
Want to learn "WHY" these questions? Keep reading -
1) Here's what I want to make ________ . Is this a good candidate for Vacuum Forming?
Many jump right in and start to hack out a machine thinking this is such a simple process and machine, I'll just spend a few hours or a weekend and whip one up. Caution: There are many types, sizes and qualities of machines that can make a major difference in what you buy or build and more importantly the outcome. If you intend to make a few parts here and there, the cost can be much different than making hundreds of parts, especially all at once.
2) I want to make (X) many parts, (X) often @ (X) size. What would be a good system for this need ?
There are certain thresholds that naturally occur where both size of subject and thickness/type of plastics will affect the answer to this question. I'll break it down to 3 categories. Let's simply call it Small, Medium and Large. This is governed by a few critical elements - the power source for heat, the vacuum power and the type/thickness of plastic.
Small - You can use a common vacuum cleaner with a hot plate to form light weight plastic with a relatively shallow draw. The size is usually smaller in area due to the limitations of both vacuum power and heating element. Both vacuum cleaner and hot plate can be powered by 110 Volt and light weight plastics can be easier to come by and form. Recycled plastics such as milk jugs and plastics sold at the local hardware store can be easily found and formed. I made a small machine called the Craft Vac that uses this method and uses inexpensive plastic food plates for stock. This is generally used for making sacrificial molds for resin, candy, soaps etc. but is also good for making clear windows and canopies for scale models. A small machine might be roughly 8" x 8" (forming plate)
Medium - Once you pass 1/32" .030" plastic thickness threshold, it takes more heat and vacuum to form a part. Both the size of the forming plate and thickness of plastics can increase however the vacuum and heat source must also increase. The good news is it can run off 110 Volt power supply but you will have to upgrade the vacuum source to handle thicker plastics. A vacuum cleaner can be used but limited to thinner plastics as per the "small". One benefit to forming thicker plastics it they can be used more for final product as they become more sturdy and durable. A medium Machine might be roughly 12" x 18" or 15" x 15" (forming plate)
Large - Going to a larger machine, the heat source becomes a bigger burden in that it requires 220 Volt to supply plastic with the optimal heat absorption. Installation may require modifications to your power supply from your electrical breaker box. This upgrade can be costly even before a Vacuum Former can be bought or built. A dedicated work space will be required since the size /weight is not easily portable or stowed. Handling large sheets of plastic requires a little more elbow room etc. A large Machine can be anywhere from 2' x 2' up to as large as you can buy a sheet of plastic for. Let's say 4' x 8' though there are larger, usually commercial systems for specific needs, like sign shops.
3) What quantity and or frequency do you intend to form parts?
Hobby or semi professional, quantity and frequency can vary greatly due to it's wide applications of uses. The quality, durability and costs of building a system can also depend on how many cycles you perform at one time and/or how often you form. Most systems are home built since commercial machine costs can be pretty steep, so the quality and durability of materials you choose should match your intended use.
4) Buying or Building?
Buying or DIY building is an important decision. Even though it's a relatively simple process, there are certain things that need to be right for consistent success. Buying can get a bit pricy for a hobby. Even for a side business, it takes a bit of time for ROI when going to a commercial machine.
5) Cost & Skill level 1-10 if I build.
Building a machine requires tools, space and a certain amount of skill to accomplish not to mention time, but if you can overcome those hurdles it's much cheaper and the results are much the same as commercial machines if done well. DIY systems can carry advantages especially in repairs and maintenance since you built it yourself. DIY machines will often have less complicated components and circuitry due to restrictions imposed upon companies that build commercially. Once built, very little will need to maintained anyway. Keeping it simple is key for a workshop setting.
6) Hobby or side hustle?
Your answer may make a difference on how much quality ($) and /or effort you build into a machine. If you're looking to do a few parts for your hobby or you want to grow a small side business, it matters. For example a small machine that uses a vacuum cleaner for vacuum and a hot plate to heat thin plastic is much different than needing a vacuum pump and surge tank to form heavier plastics with the intent of running many parts in succession.
7) ROI & Cost Effectiveness
Once you catch the fever of vacuum forming and see the possibilities, it's easy to think money will just fall in your lap. If you're lucky it will, but more often than not it can be a long learning curve looking for that cash cow. Vacuum forming is an ART in a garage setting due to so many variables to involved. Printing the part is often the easier part of actually making an end product.
8) Materials & Mold Making
9) Space for Vacuum Forming?
The space available can make a difference on what type and size of system you can accommodate. Will it have a dedicated space or will it be a portable/stowable system? Will it be a top down action (smaller foot print), flip rack or slide table (larger foot print)? Before you make the plunge, understand what space you'll need to accommodate the system. Remember - the platen is only part of the machine and usually what determines the "size" but the rest of the machine needs to be accounted for.
Depending on what you intend to form, the type of plastic used may also require more space. For example using plastics that require drying may need floor space to install a drying chamber. Some plastics need a cutting table to cut down larger less expensive sheets into formable sizes.