ABS or Delrin?

[alexismeinto]

Hi everyone,

I'm looking to build some small devices. I'll be turning most of it by hand with a small lathe. The outer diameter is about 15mm, with a central 10mm hole and a few 1-3mm holes drilled throughout the body.

I need a material that is, first most, light weight. That seems to point to ABS or maybe Delrin. Then for the machinability I'm tending towards Delrin.

Any other suggestions? Will ABS give me trouble with welding-chips unless I flood it with coolant?

Thanks

[judleroy]

In general abs machines poorly and is not good in mechanical applications because it deforms when heated.

[alexismeinto]

Is there an alternative to ABS & Delrin that has the low-mass but machines well?

[Nadiel]

Originally Posted by alexismeinto Is there an alternative to ABS & Delrin that has the low-mass but machines well?

Hello. I think the best material is ERTALYTE TX. View schedule with the coefficient of friction.

http://www.alperton.com/alperton/Mai...20Friction.htm

[alexismeinto]

Originally Posted by Nadiel Hello. I think the best material is ERTALYTE TX. View schedule with the coefficient of friction. http://www.alperton.com/alperton/Mai...20Friction.htm

I don't think that material is readily available from my suppliers (e.g. mcmaster-carr).


I'm more inclined to choose the best out of these materials (the best in terms of mass, machinability, and cost):

-ABS
-Delrin (Acetal)
-Acrylic
-Nylon
-PEEK
-PTFE
...etc...
(see http://www.mcmaster.com/#plastics/=70qy0i for more)

[mactec54]

alexismeinto

Go with your first choice Delrin, the best of what is in your list is the Peek but the cost
you may not want to pay for your parts

The Ertalyte TX , the TX means it has lubricant added & is great for bushings etc, Ertalyte by itself does not have lubricant added & is slightly better than Delrin for some things

The order of the best to machine from your list
Delrin Peek
ABS Acrylic
PTFE
Nylon

[alexismeinto]

Thanks so much!

What would you say is an approximate wall size thickness for a Delrin? Say the minimum diameter of a cylinder? Or, if you prefer, the minimum wall thickness of a bored cylinder?

Thanks again.

Originally Posted by mactec54 alexismeinto Go with your first choice Delrin, the best of what is in your list is the Peek but the cost you may not want to pay for your parts The Ertalyte TX , the TX means it has lubricant added & is great for bushings etc, Ertalyte by itself does not have lubricant added & is slightly better than Delrin for some things The order of the best to machine from your list Delrin Peek ABS Acrylic PTFE Nylon

[mactec54]

alexismeinto

It depends on what your part is for, & how much strength you need for your part, that will determine the wall thickness

[alexismeinto]

Fair enough. I'll give it a try and see.

Hopefully I can get a 1.5mm wall size with reasonable rigidity.

Originally Posted by mactec54 alexismeinto It depends on what your part is for, & how much strength you need for your part, that will determine the wall thickness

[mactec54]

alexismeinto

That is easy to do, .1mm wall is when it gets a little trick just did some at .8mm wall

[alexismeinto]

Originally Posted by mactec54 alexismeinto That is easy to do, .1mm wall is when it gets a little trick just did some at .8mm wall

Thanks Mactec.

Do you recommend using coolant when turning small parts (15mm stock) from Delrin?

I do my machining at home so I try to limit my coolant-use. Will a little bit of auto-oil or WD-40 work fine?

[mactec54]

alexismeinto

You should not use auto oil,it is not designed for use as a cuttng or machine lub,But WD-40 will work quite well for finishing cuts, if you can't have flood coolant, You should use coolant for cutting almost everything, it's better for tooling, better for finish & for stress free machining