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SPE / SPI Standards, and DME Mold Finish Kit
Q. Where can I obtain a copy of 'SPI/SPE' Standards.Rick F [last name deleted for privacy by Editor]
- McAllen, Texas
Q. Where can I get the steel finish for SPE / SPI standards?
We need to know what a SPE / SPI #5 finish is. We have looked at DME [Ed. note: Detroit Mold Engineering] Mold Finish Kit, but it does not shows any # 5 finish. They only show A 1-3, B 1-3, C 1-3 & D 1-3 finishesLeandro V [last name deleted for privacy by Editor]
plastics - Bensenville, Illinois
Q. I too am looking for this info. I have Googled all over the place but cannot find this info. We have several drawings of parts that call out finishes like SPE #4 MINIMUM or SPE-SPI #5 MINIMUM. I have found the SPE-SPI A-1 through D-3 finishing spec, but not this other scale. Surely someone out there knows what it is? I have been to the Society of Plastics Engineers and the Society of the Plastics Industry, but no luck.David G [last name deleted for privacy by Editor]
- Greenville, South Carolina
A. THE OLD WAY TO DOCUMENT SPE-SPI FINISH WAS #1-#5. SPI HAS CHANGED THIS TO A1, A2 ETC.
SPI HAS A MOLDED PLAQUE WITH SAMPLES OF THESE NEW FINISHES AND A PAPER COMPARING THE OLD STANDARD WITH THE NEW.
- Phoenix, Arizona
Thanks, L. The current place to get the "Mold Finish Guide" is at
Look for item AR-106.
I don't know the order number for the cross referencing paper for the old vs. new system, but it may be AR-101. Good luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
Ed. note: Sorry that link has been broken for a while; we don't know if it's coming back.
If there anybody who knows where can I download a free copy of the SPI-SPE surface finish standard for reference? Or anybody know what is meaning of "Gloss: SPI-SPE#2 finish" and "Matte: SPI-SPE#3 finish with liquid hone." Please help, thanks.Thomas C [last name deleted for privacy by Editor]
OEM manufacturer - Hong Kong, China
Sorry, Thomas, these are copyrighted specs, and they are for sale, not available for free. Regards,
Ted Mooney, P.E. RET
Pine Beach, New Jersey
A. The listing correlates as follows:-
#1 = A-1
#2 = A-3
#3 = B-3
#4 = C-3
#5 = D-2
#6 = D-3
The info is on page N-112 of the current DME [Ed. note: Detroit Mold Engineering] catalog. There is also a chart with further info.
Q. I want to buy SPI-SPE mold finishing guide, can I buy it anywhere in Hong Kong or China?Janet Y [last name deleted for privacy by Editor]
- Hong Kong
June 8, 2009
Q. I am looking for guidance on texturing standards for injection molded parts that goes beyond the SPE/SPI AR-106 guidance which appears to just discuss polished and blasted finishes. I am looking for etched, cross-hatch, and other more "aesthetic" finishes.
I would like to reference, if possible, a better defined standard than an internally used description that individual metal finishers use in their sales literature.
product development - Maple Grove, Minnesota
September 30, 2009
A. SPI FINISH GUIDE
A-1 GRADE #3 DIAMOND BUFF
A-2 GRADE #6 DIAMOND BUFF
A-3 GRADE #15 DIAMOND BUFF
B-1 600 GRIT PAPER
B-2 400 GRIT PAPER
B-3 320 GRIT PAPER
C-1 600 STONE
C-2 400 STONE
C-3 320 STONE
D-1 DRY BLAST GLASS BEAD #11
D-2 DRY BLAST #240 OXIDE
D-3 DRY BLAST #24 OXIDE
SPI Finish A-1 -- Grade #3, 6000 Grit Diamond Buff
SPI Finish A-2 -- Grade #6, 3000 Grit Diamond Buff
SPI Finish A-3 -- Grade #15, 1200 Grit Diamond Buff
SPI Finish B-1 -- 600 Grit Paper
SPI Finish B-2 -- 400 Grit Paper
SPI Finish B-3 -- 320 Grit Paper
SPI Finish C-1 -- 600 Grit Paper
SPI Finish C-2 -- 400 Grit Paper
SPI Finish C-3 -- 320 Grit Paper
SPI Finish D-1 -- 600 Stone Prior to Dry Blast Glass Bead #11
SPI Finish D-2 -- 400 Stone Prior to Dry Blast #24 Oxide
SPI Finish D-3 -- 320 Stone Prior to Dry Blast #24 Oxide
SPE -- The Society of Plastic Engineers
SPI -- The Society of the Plastic Industry
- Dongguan City ,Guangdong province, China
Q. I wonder if anyone knows were I might find a chart the compares SPI surface finish to a RMS or a Ra surface finish?Jay C [last name deleted for privacy by Editor]
- Pittsfield, Massachusetts
February 5, 2015
Q. SPI also produced a "Cosmetic Specifications of Injection Molded Parts" (AQ-103) document with a Surface Identification and Classification scheme which closely parallels the Mold Finish Guide scheme, i.e., surfaces A through D and grades 1 through 4 -- but really speaks more about how a part should be inspected. This would seem to be confusing since they mean very different things. Does anyone have a nice way of distinguishing these callouts on a drawing?
- Waterloo, Ontario, Canada
January 20, 2016
Q. I'm interested in a final appearance of a SPI C3 finish. With a a picture to show the part in question, it has a surface appearance and feel that is not smooth. The part is a 3D printed FDM part. Can someone email me a picture of the required or close to surface appearance of this call out?David Torres
- Huntington Beach, Califronia. United States