Materials for machining fine detail for model making

[tallen84]

I was wondering if anyone has any recommendations for materials for machining very fine details for a model (cutting with 0.01" and 0.03" bits). The larger pieces and majority of the model are already made from 15 lb Duna Corafoam, however, its not quite solid enough for the very detailed parts.

I did try making the details using a test sheet of ABS, PVC, and Polycarbonate plastics but in each case the small parts flexed and didn't machine cleanly.

I was looking at maybe general plastic's FR-4600 series microcell foams, has anyone tried these and how do they compare to the duna corafoam?

Thanks in advance!

[Kyle Stapleton]

Corian holds detail great.

[Greybarn]

Have you tried Prolab65?

[Burkhardt]

Maybe 360 "free machining" alloy brass? Cuts nicely without coolant, obviously this needs very light slow cuts with your small bits since it is much harder than wood or foam.

[tallen84]

Thank you for the quick follow up!

@kyle, I have tried Corian before but I seem to get somewhat comparable results to ABS plastics where the fine pieces will tend to bend out of the way instead of cutting cleanly. I even tried playing with a bunch of different speeds / feeds with no luck. When carving into a larger block I agree it does tend to hold detail very nicely and I will keep that in mind for some other uses i have coming up, I really need to find a supplier of either scrap kitchen pieces or inexpensive stock.


@Greybarn, I am not familiar with Prolab65. From appearance it seems similar to other HDU products, do you know how it compares? I will look to see if i can get a small piece or sample to try out. Problem I had with the FR-4600 from general plastics is that they wouldn't send a big enough sample to test and their minimum order quantity is quite large / expensive.


@Burkhardt, I had not considered any metals such as brass. That might indeed hold some good detail. Might cause some other issues (like budget :eek: ) but i will order some and give it a try.

[Chuck Keysor]

Hello Tallen. I too have experimented around with lots of materials trying to do fine detail cutting, and had also considered aluminum and brass. But I stalled out as happens all too often. I will be interested in what you find. So I hope you publish your results. Thanks, Chuck

[Kyle Stapleton]

What does the part look like you are cutting?

[tallen84]

I am actually making a 3D model / sign for my daughter's room. It looks like a tweaked Disney world castle and will have her name engraved underneath. I have already carved all the main parts out of Duna corafoam and now i just need to carve a bunch of small details to add on. Rendering of my castle model below:

29387

[Chuck Keysor]

Tallen, I tried to open your attachment, and got an error message saying this was an invalid file type (or something like that).

Also, here is the type of detail I want to mold. I have cut these types of things as V-carvings, but they are hugely time intensive. Chuck

http://www.talkshopbot.com/forum/attachment.php?attachmentid=29388&stc=1

[tallen84]

@Chuck, here i tried uploading again:

29395

[Chuck Keysor]

@tallen,,,,,,,,,, Yikes! The amount of detail there is incomprehensible! I can't imagine getting a super high resolution model of that, without it being really big. The few 3D carvings I have made, I had to get the level of detail I wanted with some chisel work, and that was mostly to create sharp crisp "chiseled" lines. I could never chisel your model............. Now that you have posted a picture, I will be interested to see what knowledgeable people have to say. Thanks, Chuck