Phil,
I read your paper, nice work! I wonder though if you did any work
relating to the flash fire method? We use that specific method here at
Williams and would benefit from that sort of information. Here are some
items that we discovered and think that most would benefit from with
further discussion:
1 - The temperature/humidity levels during the first few coats of the
shelling process are at times are more critical then the structure of the
SL pattern.
2 - We have found that any solvents used on the SL pattern WILL in some
way react with the face coat.
3 - We have found that the placement of drains/vents that are put on
during the shell process will be critical to successful burnout.
4 - We have found that the addition of air during the burnout process is
critical for a clean burnout (not necessarily a complete one).
5 - As always the introduction of moisture during the build process will
result in an unusable pattern, the introduction of moisture after cure
will result in a pattern that may be oversized (swelling). By the
way...We have NOT been able to remove moisture in a cured or uncured
pattern regardless of the amount of silca-gel we put in a plastic bag or
how dry the dry chamber is. How much swelling can you expect? We had
patterns at times that were .040" to .050" over the upper limit on those
parts!
Food for thought.....
Karl
----------
From: owner-rp-ml
Sent: Monday, September 21, 1998 7:23 PM
To: Rapid Prototype Mailing List
Subject: ATTN: Phill Dickens RE: Investment Casting Paper
>With a large amount of help from one of my students I have placed the
>paper in our ftp site:
>
>ftp://ftp.dmu.ac.uk/pub/manufacturing/
>
>You can locate this easily (I hope) and take the paper which is called
>paper.rtf
>
>Please let me know if this works!!
>
>Prof. Phill Dickens
>
Phil:
This works great - it was a little slow bringing up the ftp site but no
big
deal considering the distance the electrons had to travel!
Thanks for making this paper available to us!
Regards,
Glenn Whiteside
e-mail: siderwhite@worldnet.att.net
For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
For more information about the rp-ml, see http://ltk.hut.fi/rp-ml/
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