CNC Machining of Large Invar tooling

[toolingcomp]

Hi, anyone know of a tooling company or otherwise whom specializes in the forming and machining of Invar Tooling? I have found STADCO but want to obtain some other recommendations. We would like to machine a couple of production uav molds.

I have came across

http://www.janicki.com

but have not heard too many good things about there attention to detail and lead times. Anyone found out differently? Do they just do composites or do they do invar?

Thanks for any info,

 

[Albigger]

North Coast Tool and Mold

http://www.nctm.com

does invar molds (although specializes in steel/alum).

One-sided lay-up tools or closed-molds? They may be too big for us though.

Is there a specific reason you require invar tooling?

--Jay

 

[toolingcomp]

Thanks Jay, The program is early in the development (a uav) and suspect the tools to be approximately 30 to 40 ft long and one-sided lay-up tools. The customer will most likely request invar tooling for production.

Companies with large scale milling machines seem hard to come by. Was informed today Scaled Composites has a fairly large CMS machine

http://www.scaled.com/services/cms_mill.html

and also Brammo in Oregon

http://www.brammo.com/index.php?option=com_content&task=view&id=55&Itemid=129

Also, Rocky Mountain Composites is highly recommended. Sounds like they have developed a proprietary tooling concept for constructing composite fuselages for business jets.

 

[Albigger]

Well, when you want to get some ROM pricing and quotes, it can't hurt to have as many sources and as much input as possible. I strongly suggest you to at least talk with us and we will work with you.

As I mentioned we specialize in metal tooling mainly for the aerospace industry, and our sister-company, north coast composites, can perform tool-verification parts if those services are needed.

We have built large and segmented (if necessary) tools before. One of our larger mills has around 5ft x 12ft travel, and is made for high-speed metal contour cutting. While this is probably smaller than some machines you will find, there is also a difference between machines that are made to cut foam or light-duty materials and those that can cut invar and steel. I don't know what tolerances you have, but we can work to very tight tolerances, +/- .001 to .002 even on large scale parts.

-- Jay

 

[Compositepro]

Invar tools are very durable but there are drawbacks.
They are:
very expensive to make
require long lead times (sometimes 6 months or more)
very heavy, which may require special forklifts
very high thermal mass which requires energy to heat and results in low heat-up rates which can cause cure problems.

As a result carbon fiber/bismaleimide tooling is becoming popular. BMI tolerates the thermocycling well, weighs 10% of an invar tool, and can be made far more quickly.
A master model can be made from plaster or machined from monolithic graphite (which is very easy to machine)and then BMI tools are cured on the master model.

ACG makes BMI prepregs for tooling

http://www.advanced-composites.com/what-we-do/aerospace/

Coast composites can machine masters

http://www.coastcomposites.com/news/promill-250.html

 

[bklauba]

Also, COAST COMPOSITES, Irvine, CA.

BK