What is a vacuum press
A vacuum press is a very simple and efficient way to perform veneering and laminating tasks either in home workshop or indusrtrial settings. The equipment consists of a sealable PVC bag and a vacuum generator. This can be a small venturi such as supplied with our low cost starter kits or an electric vacuum pump as used in our MiniPress and Professional ranges. If the bagpress is being used to create curved forms then a mould is also required. In the past, these tended to be made of solid material such as MD, plywood or chipboard but now Bagpress has pioneered the use of high density extruded and expanded polystyrene foam as mould making materials. This makes it much easier and cheaper to make your own moulds and Bagpress also offers a CNCmould making service called STYROMOULD allowing you to order your moulds by email or fax and let you get on with making money rather than being occupied making tooling.

How and why does it work?
In the simple terms, you put your mould and glued up layers on material in the bag, seal it, and then suck the air out with your vacuum generator. Once you have removed the air you have created a pressure differencial between the air (or what's left of it) inside of the bag and the air outside and it this pressure that is used in vacuum pressing. Why does it work? Air is all around us, on all sides and for a considerable distance above. Just as the deeper you go under water the higher the pressure being exerted on you, if you are on land at sea level you have a considerable volume, and therefore, weight of air pressing down on you. Around 1kg per square cm in fact. Now that might not sound a lot, but when you multiply it up it works out at nearly 9 tonnes per square metre! Our vacuum generators and electric vacuum pumps develop up to 95% vacuum and so exert anything up 8250kg per square metre on the contents of the bag. Not as much as you can create on a small area with a mechanicam clamp or hydraulic rams but a very significant level of pressure nonetheless. It is also important to remember that this pressur eis entirely even and also nidirectional. By this I mean that if you imagine you are laminating a complete semicircular panel, the pressure being exerted on the sides is identical to that being exerted in the middle. This is impossible to acheive using the male/female former method of laminating as generally speaking you are only apllying pressure in one direction.

How big is a vacuum press?
How big is piece of string? The standard bags that come with our low cost Starter and Minipress kits is 775mm x 1220mmwhilst the Professional systems are all supplied with bags measuring 1350mm x 2500mm so you can get a full 8x4 sheet inside. Bigger bags are available from stock and we can get any size made up to special order, the biggest we have made so far measured 10000mm x 4500mm and took two people to pick it up!

Does it do anything else?
If you are considering buying one of our BPEL08 or larger Professional systems then you can use the pump assembly to power vacuum hold down pods and also for vacuum templating. This is a very quick and easy process that is perfect when you have to make multiple copies of a shaped part. You simple make a master template, stick sealing foam around the base and fit a connection for your vacuum tline through the top. You can then suck the templeate down onto a rough cut blank before running the whole assembly past a top bearing trim cutter on a router table thus trimming the blank to the shape of the template. This speeds up production no end and you may never need to buy a toggle clamp again!