Re: Beam-comp on QC parts

From: Curtis Wahlgren (
Date: Fri Apr 28 2000 - 20:47:40 EEST

Mr. Casey,

Yes you can make QC parts with beam-comp turned off. However the proper method to use if you want to insure accurate
QC parts is to build a set of 'Christmas trees' with beam comp turned off and no scale factors applied. With the measurements
taken from these parts you can establish a beam comp and scale factors in x and y (there is usually no scaling done in z) that
are appropriate for your particular machine and resin. Build another set of trees using these values for beam comp and
scaling and measure them again. The dimensions should now be quite accurate. Make sure that you build the trees in the QC
style and not as solid pieces.

If you don't know how to build and measure the 'Christmas trees' you can contact me for more information.

Yes you can use a sealer to coat the QC parts. This is a common practice and helps to keep the dimensions of the part from
changing with time, particularly in moderate or high humidity environments. I can't recommend any particular coating material
because I don't have experience with doing this. I assume that you are building these parts for a foundry so they may be able
to give you advice on this depending on their experience with QC parts. One consideration you need to bear in mind is that
the ceramic slurry will need to have good wetting and adhesion to the outside of the part. You don't want to use a coating that
will prevent this from happening.

The cast metal part will not have the same dimensions as the QuickCast part you build (normally it is smaller). However it is
the responsibility of the foundry to take these factors into account when requesting the QC part from you.

I know that there are readers of this list with more experience in these matters than I have. I hope that they will be kind
enough to correct any incorrect or incomplete information that I have supplied.


>Date: Wed, 26 Apr 2000 10:17:22 -0500
>From: "Benjamin, Casey" <>
>Subject: beam-comp.
>List, I have a few questions about Quick Cast parts if someone could help
>me. 1.) can you make a QC part on a SL 5000 using Buildstation 5.0 with the
>beam-comp turned off, if so does the part need to be scaled?? 2.) Can you
>use a sealer or laquer on QC parts like you would with Weave parts??
>Casey Benjamin
>Tool Engineering
Curtis Wahlgren, Ph.D.
DSM Somos
2 Penn's Way, Suite 401
New Castle, PA 19720
(302) 328-5635

For more information about the rp-ml, see

This archive was generated by hypermail 2.1.2 : Tue Jun 05 2001 - 23:03:22 EEST