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Michael Carter
02-20-2007, 11:44 AM
I'm just starting on the MIP, and I'm trying to use the actual MIP from the Boeing 727 as much as I can. I have three pieces of the MIP and hopefully can find the other three.

I'll have to make my own instrument bezels for the holes in the panel and I need some advise on the type of plastic I should use for these. It needs to be easily worked with both a hobby knife and a bench top Dremel router.

My McMaster-Carr catalog has tens of different plastics listed. PVC, ABS, Acrylic, Styrene, Polyethelene, etc, etc.

I've worked a lot with styrene and it's OK, but I was thinking about PVC since it's already molded in dark grey. Acrylic is out because it's too brittle and difficult to machine.

Trevor Hale
02-20-2007, 12:06 PM
Some Problems with PVC and ABS are they will melt before they cut, you will have to be careful with your dremmel.

Especially PVC, that dark grey will trun brown if your not careful.

Good Luck,

Trev

Westozy
02-20-2007, 06:19 PM
My whole sim is grey PVC, it's easy to machine and can be kept cool when machining with CRC spray. (Light spray lube). Use high speed settings on the Dremel and only use sharp tool bits. I made my MIP in a day with the Dremel in a router attachment and have had no problems making PVC parts. The PVC I used is called, "Trovidur". It's easy to glue pieces together with super glue aswel.

Gwyn

Trevor Hale
02-20-2007, 06:46 PM
LOL!

Thanks for taking the wind out of my sales Gwyn :) ROFL

Polmer
02-20-2007, 09:41 PM
I have had great luck working with "sintra board",which is a closed cell PVC foam.
It is light weight, easy to work with, yet very strong.

You just have to be carefull when you take a dremmel to it because it will cut through it like butter sometime.
I have not yet seen this material melt.



Polmer

dodiano
02-20-2007, 09:47 PM
Milky White acrylic is a good material to use but I have to differ a bit with the high speed on the dremmel actually lower speeds at least on a CNC when cutting plastics and acrylics is better so you avoid melting unless you use a coolant!!

Regards,

Roberto

Michael Carter
02-20-2007, 09:56 PM
Thanks for all of the suggestions. I'm going to see if I can find some of that Sintra board and order a sample.

I may order several samples beore I decide. Thanks again for the advise.

I'm really leaning toward the dark grey PVC.

Westozy
02-20-2007, 10:47 PM
I did mention the coolant Roberto, (CRC spray), Machining is my trade!

Gwyn

Polmer
02-20-2007, 11:15 PM
If it helps,

here is a link to the Sintra board the supplier I used;
http://www.usplastic.com/

Just do a search for "sintra" on the site for the various types.
I ended up going with 1/4 inch sheet thickness.


Polmer

dodiano
02-21-2007, 12:55 AM
Yeah I`m actually a Amateur machinist have been learning with my CNC the hard way LOL! But it is fun still Aluminum is a pain in the *** for me!!

Roberto

Michael Carter
02-21-2007, 06:04 AM
Thanks for the link. I found the stuff on several sites. I've actually used that in the past but didn't know that is what it was called.

I made a new dew shield for my 6" refractor several years ago and used the foamboard as diffuser rings inside the tube.

The only thing that concerns me about using the foamboard is the raw edges will be somewhat porous. I might experient with some I have here in the shop.

JW&Partner
02-21-2007, 08:46 AM
@ dodiano

just use ethyl alcohol for cooling, high speed rotation and a low speed motion and it will work. But most important is the alcohol...
But open the window not to get drunk :-)

regards Jörg

dodiano
02-21-2007, 11:06 AM
Or maybe we should let the window close and get Drunk... LOL!! Thanks!

Roberto