RE: [CAD_CAM_EDM_DRO] Delrin was (Re: all-thread question

Hi Dave,

From what I've gathered Delrin (Acetal), Delrin is the Dupont tradename, is
a bit shinear then Nylon. Nylon tends to be duller and not as strong. Here
are their respective properties.


Physical Properties Nylon Unfilled (English Units)

Density 0.0379 - 0.0475 lb/in³
Water Absorption 0.35 - 2 %
Moisture Absorption at Equilibrium 1.8 - 2 % 1.8 - 2 %
Water Absorption at Saturation 2 - 5.5 % 2 - 5.5 %
Linear Mold Shrinkage 0.0028 - 0.01 in/in
Melt Flow 3 - 6 g/10 min 3 - 6 g/10 min


Mechanical Properties

Hardness, Rockwell R 69 - 105 69 - 105
Tensile Strength, Ultimate 4640 - 13500 psi
Tensile Strength, 3920 - 6240 psi
Elongation @ break 2.5 - 360 % 2.5 - 360 %
Elongation @ Yield 3.2 - 13 % 3.2 - 13 %
Tensile Modulus 131 - 653 ksi
Flexural Modulus 160 - 653 ksi
Flexural Yield Strength 5950 - 17400 psi
Izod Impact, Notched 1.46 - 20 ft-lb/in
Izod Impact, Notched Low Temp 4.68 ft-lb/in
Charpy Impact, Unnotched NB NB Grade Count = 4
Charpy Impact, Unnotched Low Temp 2.86 - 10.9 ft-lb/in²
Charpy Impact, 4.76 - 35.2 ft-lb/in²



Physical Properties Delrin Unfilled Extruded (English Units)

Density 0.0509 lb/in³
Water Absorption 0.2 %
Moisture Absorption at Equilibrium 0.9 %


Mechanical Properties

Hardness, Rockwell M 89
Hardness, Rockwell R 122
Hardness, Shore D 86
Tensile Strength, Ultimate 11000 psi
Elongation @ break 30 %
Tensile Modulus 450 ksi
Flexural Modulus 350 ksi
Flexural Yield Strength 13100 psi
Compressive Yield Strength 16000 psi
Shear Strength 8990 psi
Izod Impact, Notched 0.993 ft-lb/in
Compressive Modulus 450 ksi
Coefficient of Friction 0.25 Dry vs. Steel
K (wear) Factor 200 10-10 in3-min/lb-ft-hr
Limiting Pressure Velocity 2570 psi-ft/min


Hi Russ,

Let me know the size piece you need for the Delrin.

I have some of what I think is black Delrin plate, 1" and a 2" rod
too.

If you wanted to buy that stuff, McMaster Carr again. A 2" bar, 12"
long goes for about $13.00.

My question is how to tell if the stuff is black nylon, or black
Delrin. Is there a simple test ? (fire, file, folding?)


Dave

--- In CAD_CAM_EDM_DRO@y..., "Russ Revels" <n4ft@a...> wrote:
> Thanks Smoke and Dave,
>
> After reading your replies I looked in the McMaster Carr catalog
and found
> some bronze bushings that look like what you describe. I have 1"
5tpi rod
> and the bushings are 1" id and 1 1/4od by 1 1/2" long. Judging by
your
> description I should be able to pin the bushing to the thread and
then run
> the bushing into a bearing. It appears like that will be an
inexpensive
> solution to what could be a costly machine shop task.
>
> I remember someone mentioning a while back that they had made nuts
from
> delrin. Is there a tap for acme 1 x 5? Or is this something that
would
> have to be done on a lathe? I am not familiar with the metal
working
> machines all of my tools are for wood. Is anyone aware of a source
of delrin
> or uhmw nuts that would work on a small router table setup?
>
> Thanks again,
>
> Russ N4FT


Addresses:
FAQ: http://www.ktmarketing.com/faq.html
FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/

OFF Topic POSTS: General Machining
http://www.metalworking.com/news_servers.html
http://www.metalworking.com/news_servers.html

Post messages: CAD_CAM_EDM_DRO@yahoogroups.com
Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
Moderator: jmelson@... timg@... [Moderator]
URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
bill,
List Mom
List Owner



Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/