Thread: Is Delrin available in australia, for making an EvaNut

Delrin is the DuPont tradename for acetal resin.

It is available in various grades, as are other brands of acetal resin.

http://www.complast.com/delrin/DelrinData.pdf

Here's an ebay seller in Melbourne that has Delrin

http://www.ebay.com.au/itm/Black-Ace...item4ad2d64c3e

For this sort of stuff, I generally ring Cadillac Plastics. for UHMW, Teflon etc, the local bearing places usually have a good selection.

Ray

Originally Posted by twopintsplease

I wish to make an EvaNut for a hercus lathe I purchased some acetal rod and have had a couple of goes and sofar has not worked out to well, the nuts are just to tight and i can seem to chase out the thread to get a nice running fit with no play

I have been using Ertacetal "C" from Dotmar plastics, they list Ertacetal "H" but dont stock it, special order only 12 plus weeks etc

Tryed E-Plas same story only the Copolymer is avalable

After re reading the post on the home shop machinest site again Evan stipulates the use of Delrin a homopolymer and after a bit of a look on the net i cant find any one in australia that stocks it

Has any one here had any luck in making an EvaNut ?

or recomend a suppler on line ?

Looking forward to your thoughts

(edited for spelling)

I bought some from RS components in west aust. ? the postage was free from memory.

Originally Posted by RayG

Here's an ebay seller in Melbourne that has Delrin

http://www.ebay.com.au/itm/Black-Ace...item4ad2d64c3e

For this sort of stuff, I generally ring Cadillac Plastics. for UHMW, Teflon etc, the local bearing places usually have a good selection.

Ray

I was going to hit the buy it now button on that same piece the other day but hesitated when I found a US seller offering a variety of sizes for less with a fixed shipping price that seemed reasonable. Hesitated because I didn't know how much the stuff costs locally from a seller such as E-Plas. http://www.ebay.com/itm/Exact-Metals...item27bf015581

Bob

ps What's an EvaNut ?

Originally Posted by Anorak Bob

ps What's an EvaNut ?

Melted crossslide nut. Ibelieve
Stuart

Originally Posted by twopintsplease

I wish to make an EvaNut for a hercus lathe I purchased some acetal rod and have had a couple of goes and sofar has not worked out to well, the nuts are just to tight and i can seem to chase out the thread to get a nice running fit with no play

I have been using Ertacetal "C" from Dotmar plastics, they list Ertacetal "H" but dont stock it, special order only 12 plus weeks etc

Tryed E-Plas same story only the Copolymer is avalable

After re reading the post on the home shop machinest site again Evan stipulates the use of Delrin a homopolymer and after a bit of a look on the net i cant find any one in australia that stocks it

Has any one here had any luck in making an EvaNut ?

or recomend a suppler on line ?

Looking forward to your thoughts

(edited for spelling)

Yes I've made two or three !

Nut-02.JPG Nut-01.JPG

This is one that I made for my digital hight gauge modification.

Measure-01.jpg Adjustment_Arm-02.JPG Adjustment_Arm-03.JPG

You can see the nut pressed into the aluminium housing in the two pictures on the right, and the finished hight gauge on the left.

The technique requires that you apply sufficient heat to the threaded rod in order to melt the plastic from the inside whilst squeezing it in the vice. I've tried a couple of different plastics, one polycarbonate, which is a hard plastic often used for screwdriver handles. This one made a good thread and might have made a good nut, but it simply broke up whilst trying to get it to release from the threaded shaft after turning it to size.

Originally Posted by twopintsplease

the nuts are just to tight and i can seem to chase out the thread to get a nice running fit with no play

What about partially cutting along the original threaded part with an angle grinder to produce a section with a wire edge so you can use that section to chase out the delrin nut once it is melted into shape?

Hi Guys,

I think that part of the problem with getting the moulding off the threaded rod is that the rod is not necessarily perfectly round. I ran a die along a length of threaded rod and found that (a) the galvanised coat wasn't even and (b) the rod was slightly oval. In fact when I used the die it seemed that it got a little more tight every ten or twelve inches. Its as though the rod was being twisted as it was being threaded.

Certainly on the 1/4" x 20 rod that I used running the die along it eased the nut quite a bit. The acetal / deralin freed off on a length of 14 mm x 8 acme threaded bar with a little more ease, but it was far harder to get it hot enough to mould properly.

HTH.

Just called E-Plas over here. 40mm dia. x 1 metre of black Delrin will cost me 25 bucks plus gst. Sounds like good value.

BT

Sustarin® Acetals

SUSTARIN® Acetals, also known as PolyOxyMethylene or PolyFormaldehyde, are available in two types, Copolymer and Homopolymer, and both are highly crystalline linear thermoplastic polymers.

cut and paste from the E-plas web site, sorry about the formating, they dont sell Delrin it is a Dupont trade name, they list a Homopolymer but dont stock it only on special order, Dotmar is the same they sell an Acetal made by Quadrant and only stock Copolymer.


Acetal Rod, Delrin Rod, Acetal Sheet & Tube
Dotmar offers both homopolymer and copolymer grades of Acetal Rod, Sheet and Tube. Ertacetal®C (Acetron® GP) is porosity-free and offered as our standard general purpose grade. For slightly higher mechanical properties, we offer as a non-standard, homopolymer Ertacetal® H (Acetal) (Delrin®) products.

Ertacetal H (Delrin), homopolymer acetal rod, sheet and tube offer slightly higher mechanical properties than Ertacetal C Acetal, but may contain a low density centre, especially in larger cross-sections. Ertacetal C (Copolymer) also offers better chemical resistance than momopolymer acetal. Ertacetal H is suitable for small diameter, thin-walled bushings that benefit from the additional strength and rigidity of homopolymer acetal
Cut and paste from the Dotmar site same story only stock Copolymer any thing else is special order

what i have been trying is a Ertacetal C a Copolymer from Dotmar wish to try a Homopolymer to see if the out come is different

Thanks for the tip, and R.S. sell a Dupont product and have a data sheet that lists it as a Homopolymer i have ordered some and its on its way i will try it

Yes have tryed using slots cut in the thread and the thread cut in half sort of a cross between a tap and a D bit ,but so far once it has freed up it then has to much backlash, that sort of defeats the point of the exersize

Its good to see other have had a good out come with the process i think i just need a bit of fine tuning

Thanks Two Pints.

My experience with turning plastic is extremely limited. I have an immediate need to acquire some suitable plastic for the purpose of demonstrating to my daughter a few basic turning procedures. She is studying jewellery design and has been inspired by the work of a pair of jewellers whose work features turning. She flys home from Melbourne on Sunday.

I did have a fiddle with some Plexiglas. Cut beautifully on the mill but I haven't tried turning the stuff. On the mill it cut with small crisp chips, the nature of a slot drill's cutting.

Is there a plastic you would recommend?

Bob.

Sorry to butt in, Bob have a look at pen and bottle stopper blanks. They are available in either thermosetting polyester resin (ie cast) or acrylic resins (thermoplastic) and both turn and mill very nicely.

Have a look at the likes of Timberbits some of the other pen blank suppliers who are members of this forum.

HazzaB springs to mind in your neck of the woods.

Also Woodnworkshops

http://www.woodnworkshop.com.au/index.php?cPath=21&osCsid=2e7ad27740a0d5111b1d799f6deb056d

http://www.garypye.com/Acrylic-Blanks-c38/

The PVC plastic used for water and sewer pipe by the city are the right price for jewelry practice. Only downside is the turning swarf doesn't break on its own so wraps around the work. Ya gotta stop and remove it often. Threads well too.
Pete

Don't get me wrong Bob Acetal is beautiful to turn and gives a lovely finish and these company's are selling a quality product but my frustrations lie in the fact they have a catalogue full of product that they don't stock and the sales persons are just order takers and some don't even know or understand what they are selling , with the death of manufacturing in this country I can only see this getting worse, that said rant over ,I dont think you will be disappointed with acetal from E-plas and yes that seems a good price

I am surprised with my lack of success when other describe it as quite a strait forward process will keep plugging away