Carving From Foam

[Clayton Jones]

You might take a look at the 3D .PDFs that the Whitmer Lab has produced. They have a T. rex!

The skull is a 3D model produced from CT scanning so it contains all the internals and not just the stuff you see on the outside. The whole skull is there! You can turn it around and hide certain parts to get a better view, perfect for your project.

Don't forget that tyrannosaurus had heterodonty, not all of it's teeth are the same shape.

[Koss1959]

Thank you. I can't seem to do anything with the pdf's. I've downloaded them and opened them but I can't do anything more. I think it's because I'm on my tablet rather than a laptop.

[Clayton Jones]

They do use up a bit of resources, especially the high-res versions... Usually you have to click once on the image before it will load the model so that you can rotate it around, but you might not have the right drivers or software to properly display the model on the tablet.

I could always screenshot angles for you if you can't get it to work.

[Koss1959]

Got started today. The foam was thinner than anticipated so the model is going to be made of several sheets glues together. Four at the thickest end of the skull. Even now I'm starting to become painfully aware of the challenge I've chosen to taken on. I've only started to draw out the templates but am already thinking how I'm going to hollow it out. Or if I even should. I think I might need a hacksaw to do some bulk removal, knives are hard work for cutting away larger pieces. Sandpaper will definitely be needed. Looking forward to doing some proper work on it tomorrow morning. Will take some pictures later even though nothing exciting has happened yet.

Question for this update:

Seeing as it is going to be made out of four pieces of foam, do you think it would be easier to hollow out the inside bits of foam before glueing together?

[LordTrilobite]

Personally, I don't see the need to hollow it out on the inside. the foam weighs almost nothing to begin with, so that's not really a problem. And If you leave the inside intact. You can always decide later to also carve the inner parts of the skull. Or just leave it filled with "Matrix".

[Koss1959]

It's quite convincing. Seeing as this is my first build, I might do that for simplicity's sake.

This foam is harder to cut than I expected. Cutting one way is fairly easy and can be done somewhat neatly with a kitchen knife, but cut the other way and it's a lot harder. Going to buy a hacksaw tomorrow so I can get the basic profile shaped. Then I'll glue the pieces together. This is not what I was expecting. Suddenly I realise the other models people have made on here are a lot more impressive than they seem.

Edited August 26, 2014 by Koss1959

[Koss1959]

Pieces glued together. Gotta leave it an hour to set then I can get on doing the basic shape. There's gaps between a few foam layers as I don't have any claps to hold it down. Shouldn't be too much of a problem.

[LordTrilobite]

Don't forget to post pics of the process!

[Koss1959]

Will do. Shaping it and rounding it off is hard. The nose isn't too bad but the rest of it will be difficult. Sandpaper seems pretty effective.

[squali]

I would suggest the next time you glue up some foam boards to place a sheet of plywood over the top and put weights or even pots of water on top to set the glue.

you don't want so much weight that the foam is distorted, just held in contact.

[Koss1959]

Thanks. This is the first time I've done anything like this. It's an easy fix. I'll just glue some wedges of foam in there and sand it down so you won't even notice.

[Koss1959]

Here's my progress. Pretty featureless and boring at the moment. I don't have high hopes for this anymore. I'll see it through but it's a lot harder than I imagined. I'll keep going and get better soon.

[LordTrilobite]

Looks good so far. You know. you can probably fix that gap by carefully breaking that piece of foam off of it again and glueing it again with more foam in a can.

[Koss1959]

I'll probably just wedge some foam in there and sand it level. How do you make the holes for the eyes and other cavities? I'm finding it very difficult to carve into the foam in areas where it bowls inwards.

[LordTrilobite]

For concave areas I generally draw a the outline of the hole with a short knife straight into the foam. Then with the same knife I draw a small grid, also straight down. Then I use tweezers to pluck out the individual box-shaped pieces, creating a hole. It's messy, but it gets the job done.

[Koss1959]

So essentially cross hatching the area? I'll give that a go, thanks. I've got a day off today so I should have plenty of time to make progress.

No point making a new post...

Lots of progress today. The general shape is coming on nicely, still got a way to go though. A few of the holes have been made. The skull is now in two pieces so to make carving the teeth easier. I'm feeling a bit more hopeful and optimistic now about this. I think it could come out quite nicely. I don't think it's going to be an exact replica of Sue's skull anymore, just a quarter scale Rex skull.

Edited August 29, 2014 by Koss1959

[Koss1959]

Updates. Got quite a bit done now. There's some parts that I've screwed up kinda, but for my first try, it's coming out fairly well. I don't think I'm going for anatomically correct. I didn't realise what a challenge this would be.

Mainly been working on the upper part of the skull. I'm particularly proud of the nostrils. The other holes need work and the whole thing needs some work to make it symmetrical. Still got a way to go with hollowing it out.

Pictures aren't uploading so I'll have to do it later.

[Koss1959]

[SharkGuy94]

That's looking great! I've been thinking about a project to take on over the winter, this seems like a great idea! As Majungasaurus is my favourite Dinosaur, I'll probably try and make a life size skull. I look forward to seeing more updates on this skull, it is starting to take shape now!

[Koss1959]

Thank you. I have a lot of work over this next week so progress is likely to be slow.

You should do a pproject . it's a lot of fun. Very hard though. It's not as easy as I expected. Having accurate and to scale references help loads. Of all angles. You can't have too many. A massive bonus is if you can get them all from the same specimen. Mine has gone from an exact replica of Sue's skull, to a Tyrannosaur skull. An exact replica is quite an undertaking.

[Koss1959]

Small update. Adding in the final fenestra. Been doing a lot of sanding. Trying to give the skull a more rounded shape, especially on the left and right sides at the back. The back of the skull is largely unchanged, hence no picture. I still need to work on the contours, the lower jaw is still very basically shaped. I'm going to have it in a mouth closed position. Yet to work on the teeth. I'll do that last I think. And I've got to add detail into the skull, cracks, holes etc. But that's still a long way off. Here's some pictures

Edited September 3, 2014 by Koss1959

[LordTrilobite]

Looks good, though the braincase looks a little thin. I would also suggest leaving sanding paper to last. I find that knives are more precise. Even though it takes more time that way.

[Koss1959]

The picture I was using as reference (done by eye as I had no scale reference) showed it to be very thin. Much thinner than what I've made it. The sanding was mainly to make it flow better. Obviously it's made from several blocks so I was trying to make it look more like one piece. It wasn't the kind of finishing sanding.

Thanks for the advice all the same

[Koss1959]

And my poor glueing has come back to bite me in the bum Lesson learned.

Edited September 5, 2014 by Koss1959

[LordTrilobite]

Personally I think a scale reference is one of the most important things there is when making something like this. Really useful for directly comparing your work to the original material.

Looking forward to seeing the final result.