PDA

View Full Version : I know this sounds crazy but...



Kimberly Connor
12-09-2009, 5:56 PM
we have been fortunate enough to stumble into a great contact that we are working with that needs custom triangle bowl (I know a HUGE challenge for us.) We have made a mold and also a custom vacuum former to do a sample for her. It looks like it is going to work and they are going to need thousands of these bowls a month (they are international) and we just will not be able to produce them fast enough (vacuum forming them) each month on top of everything else we have going right now.

Here is our CRAZY idea. My husband has always wanted to get into manufacturing and so we thought we would start producing cast acrylic and just pouring the bowls instead of vacuum forming them. Our problem is that we have contacted a few companies that produce acrylic and they have been less than helpful in talking to us about where to begin to produce our own cast acrylic for production.

I am hoping that someone on here has a contact or an idea of where we can start to find out how to produce our own acrylic and manufacture it. We would be thrilled to offer discounts to Sawmill Creek members because of all the wonderful help you all have given us over the past year and a half. We just need to know where to start.

Thanks for any help, suggestions, ideas, etc. You have all been wonderful in the past and anything you offer is greatly appreciated!

Thanks again!

Kim

Doug Griffith
12-09-2009, 8:12 PM
Hi Kim,
I am in the vacuum forming business and think vac forming is your quickest and most cost effective process to get the job done. With the proper equipment, .250 thick acrylic will shallow form (like a bowl) in a few minutes. Most likely under a 5 minute cycle time. You need top and bottom ovens and a heated female aluminum tool to do it best. Any type of "3D" tooling such as injection molding is going to cost quite a bit. Plus acrylic is poured and has to set so you'd need multiple tools to have any type of throughput.

Michael Hunter
12-10-2009, 11:44 AM
To confirm what Doug has said really -

Cast acrylic takes a fair while to set after pouring - it depends on the thickness, but allow for at least a day in your calculations.
A whole load of moulds and a whole load of temperature controlled space to keep them in.
(I seem to remember reading that 1" thick sheets take a week to set, but thinner stuff takes a day or two).

Methyl methacrylate (the main component of acrylic) is pretty nasty stuff and whatever gets mixed in to make it polymerise is almost certainly horrid too.

Extruding is a much faster process, but needs an expensive mould tool, plus an injection moulding machine!

By comparison, the capital cost of extra vacuum forming gear is peanuts.

Rodne Gold
12-10-2009, 10:52 PM
Why use acrylic if you want to cast ? It requires heat and pressure to cure and needs to have curing ovens and the like.
Why not just use a water clear general casting resin? You can add various fillers and pigments for varied effects and even add stuff like powdered metals to get faux cast bronze and aluminium items.