Re: Cutting styrene sheet into narrow strips...


proto48er
 

Guys -

Just a wild guess, but I would think that Evergreen would have cut thin styrene sheet with a guillotine shear. The very small edge serations, if vertically oriented from top to bottom on the strips, would confirm this. Another wild guess would be that their scribed styrene sheet is made in an horizontal milling machine-like device.

I have used a 12" Di-Acro shear to cut 0.005" thick shimstock half-hard brass into 0.070" wide boiler bands ("O" scale). The width of the cut strip is set with a backgauge (in my case, a "frontgauge" for the real thin sheet), and the sheet adjacent to the cutting blade must be held down on the table while cutting to achieve an even width down its entire length. The shear will cut thin stuff all day long - have sheared styrene and phosphor bronze up to 0.030" thick, too. The width varied about 0.001" plus or minus down the length of the strips. I set the "frontgauge" with a pair of Scherr-Tumico depth micrometers so that the cut strips are not tapered.

I just sold three small 8-1/2" press brakes on Ebay. They will make a somewhat sharp bend in thin sheet brass. However, simply bending brass to a right angle will not make a dead sharp bend. The thickness of the sheet will cause a radius on the corner of the bend equal to about 62% of the sheet thickness. In other words, if you bend 0.005" thick brass sheet, you will still have a radius in the corner of the bend of about 0.003". The same rules apply to styrene.

To make a dead sharp bend in brass, you have to use sufficient "tonnage" to cause the brass to actually flow at the corner ("coining.") That is difficult. However, it may be possible to cause the styrene to flow at a much lower pressure. Frankly, I have never tried that!

Here is the Di-Acro website:

<http://diacro.com/>;

Their machines sometimes sell for reasonable prices on Ebay.

A.T. Kott

--- In STMFC@yahoogroups.com, "Kurt Laughlin" <fleeta@...> wrote:

----- Original Message -----
From: soolinehistory

I actually had some samples of Evergreen sheet cut on a waterjet, and all I
can say is, it ain't pretty. Waterjets are used to cut hard materials.
Styrene isn't that hard, and just kind of shreds.
----- Original Message -----

Harder materials can be cut (*), but they are not the exclusive application
for WJC. Diapers, fabric blanks for clothing, foam, and carpet (Did you
ever see an intricate logo or emblem in the lobby of a hotel or business?)
are among the many "soft" things it is used for.

(IIRC, really hard things like ceramics can't be cut because of surface
fracturing or something.)

KL

Join main@RealSTMFC.groups.io to automatically receive all group messages.