Machining Noryl (PPO)

[clay]

Anyone with experience with machining and turning Noryl (PPO)
plastic, compared to Delrin? I have a project where a client would like
to switch from Black acetal to Black Noryl. Also, how well does it bead
blast?

ca

[SPI01]

We machine a ton of Noryl optical components. There are very important
things to consider when machining Noryl. It has an affinity to stress
cracking, commonly between holes or in sharp corners. The use of coolants
will accentuate this characteristic. Whe have found over years of
experience that complex parts must be annealed, rough machined re annealed
then finish machined. We machine Ultem using strictly Airblast to remove
the chips as they tend to weld badly to the part. Noryl only beadblasts
slightly better than Delin. I hope this helps.
Dennis

Post by clay
Anyone with experience with machining and turning Noryl (PPO)
plastic, compared to Delrin? I have a project where a client would like
to switch from Black acetal to Black Noryl. Also, how well does it bead
blast?
ca

[Cliff Huprich]

Post by SPI01
Whe have found over years of
experience that complex parts must be annealed, rough machined re annealed
then finish machined.

You may be able to get your raw stock already annealed from a vendor.

There was at least one thread about a year ago on such. IIRC several
vendors were mentioned but I don't recall if Noryl was mentioned. Probably
not the subject at the time <G>.

A search might find the thread(s) and/or a Web search vendors. As it's
also a trademark (I think) try asking or searching at the trademark owner's
Site.

My days of free research may be over <g>.

[SPI01]

Typically Noryl is in an annealed condition, however it is only a very
minimal anneal. We use a ramp up / down program of at least 12 Hrs on 2"
round, for the initial treatment followed by a 6 hr. treatment between
roughing and finishing. This rediculous sounding proscess was not
implemented for fun, but to eiminate failed parts, and has been 98%
succesful over the past 6 years, and aprox. 18,000 parts. previously we had
a failure rate of 1 in 8.
Dennis

Post by Cliff Huprich

Post by SPI01
Whe have found over years of
experience that complex parts must be annealed, rough machined re annealed
then finish machined.

You may be able to get your raw stock already annealed from a vendor.
There was at least one thread about a year ago on such. IIRC several
vendors were mentioned but I don't recall if Noryl was mentioned. Probably
not the subject at the time <G>.
A search might find the thread(s) and/or a Web search vendors. As it's
also a trademark (I think) try asking or searching at the trademark owner's
Site.
My days of free research may be over <g>.
--
Cliff Huprich

[clay]

Dennis,

These are pretty simple shaped parts, with a threaded ID on one end, a
counterbore, and two small dowel pin holes on the other. Think of a skateboard
wheel with internal threads on one end. Do you think we will have stress issues
even then? This is also black, which sometimes minimizes the problem, correct?
The bead blasting is used to remove tool marks and provide a consistant texture.

ca

Post by SPI01
Typically Noryl is in an annealed condition, however it is only a very
minimal anneal. We use a ramp up / down program of at least 12 Hrs on 2"
round, for the initial treatment followed by a 6 hr. treatment between
roughing and finishing. This rediculous sounding proscess was not
implemented for fun, but to eiminate failed parts, and has been 98%
succesful over the past 6 years, and aprox. 18,000 parts. previously we had
a failure rate of 1 in 8.
Dennis

Post by Cliff Huprich

Post by SPI01
Whe have found over years of
experience that complex parts must be annealed, rough machined re

annealed

Post by Cliff Huprich

Post by SPI01
then finish machined.

You may be able to get your raw stock already annealed from a vendor.
There was at least one thread about a year ago on such. IIRC several
vendors were mentioned but I don't recall if Noryl was mentioned. Probably
not the subject at the time <G>.
A search might find the thread(s) and/or a Web search vendors. As it's
also a trademark (I think) try asking or searching at the trademark

owner's

Post by Cliff Huprich
Site.
My days of free research may be over <g>.
--
Cliff Huprich