How to assemble 3d printed Cosplay Props? Tutorial for the Last Word from Destiny
Let’s do your own DIY Last Word inspired by Destiny.
We have 10 3d-printed pieces, which we have to glue, assemble, do sanding and painting work. You can get all 3d printed parts for assembling here:
Choose KIT DIY version and ornament you wish to have 🙂
The Last Word was 3d printed at 0,2 microns with PLA plastic. It has 4 layers on in perimeter, which makes parts durable and light. Infill is 10%.
Instruments you need :
1. Stationary knife and /or hobby knife and small metal stick or screwdriver.
I recommend to use stationary knife, as hobby knife breaks easily, but it’s smaller and can get to places hard to reach. We need this knife and metal stick or screwdriver for dividing support materials from 3d printed parts. Recommendation: use at least working gloves and be careful, as you can easily scratch your hand.
2. Sanding paper.
Sanding paper should do smoothing and finishing work. For such purposes we need at least 2 types: rough (~180 grit) and soft (~360 grit or more). Rough sanding paper type is used for first sanding step, we should make pieces of the Last Word absolutely clear of any scrathes, some other 3d printing defects and visible 3d printed layers. Soft paper is used like finishing step, makes pieces very smooth and nice. More you do sanding work – better the model looks. But don’t try to sand holes in it 🙂
We need this to glue pieces. There is no specific glue, so you can choose any good glue for plastics. Glue should work in 5-15 minutes. I would not recommend use 5-second glue for main purposes. We would need our later. Recommendation: glue should have transparent color, this will help us during the assembling and finishing (but you can buy any color glue).
4. 5-second glue
We need also 5-second glue to help main glue with assembling. We use it only for gluing small pieces, corners etc. It is not very good for main purposes. We use it after we have glued with the main glue (3) all parts, and we fill in with super-glue the gaps that have remained.
5. Rotary engraving tool.
You can use Dremel tool if you have it or any other brand. This tool makes the process faster, as you can easily smooth like 50%+ of the gun with the machine. It has many different attachments and I would recommend using same grit papers (around 360 and 180). It is not necessary but if you have it – cool! The only thing that you should know while using it – you have to be careful while sanding the 3d model. If you push to hard – you can easily make a hole/scratches in the model. When you do sanding with sanding paper by your hand – you will not be able to ruin the model.
I would recommend using clamps, as these things hold parts very good when you have glued them. Clamps stick to each other parts very well. Also, you need to know and check how do they hold parts, while the glue is wet. When you glue pieces and parts are yet not assembled (glue is still wet), you can put clamps and they compress parts, and parts may move because of clamps power. Make sure you have attached clamps good and glue is already not as wet as at the beginning. Otherwise, parts may move and be glued not evenly.
7. Gap filler
Bondo is ok, well-known gap filler. But we use another gap filler for woods and plastic and it also works well! You can buy it in any hardware store. The main thing – it should be good, do not crumble after drying. The main idea of gap filler is that it should fill in gaps between parts after they have been glued, to make the gun look as a one-piece model.
And now steps to assemble
Step 1. Delete all support materials.
We should remove all support materials after parts have been 3d printed. For big support pieces use a metal stick or thin metal screwdriver. For small supports – knife. I would not recommend using hobby knife for main purposes as it brakes easily, but if you use it carefully – its ok. Use only for small and hard-to-reach places. Stationary knife, in my opinion, is best for all needs. And if you break it – not a problem, it is easy to change or cut the blade.
Step 2. Glue main parts.
Recommendation: before gluing, do sanding a bit on places where you have to glue parts. There are small scratches and sanded surfaces have better adhesion. We need to glue handle, 1st middle parts, 2nd middle parts and front parts. For now, do not glue the whole gun, we will do it later.
Step 3 Glue main parts with a 5-second super glue
We need to glue with small pieces, corners around the perimeter of each glued part previously. The glue will also make assembling better. As you can see, I add 5-second glue after all parts are assembled, but there are small gaps remaining. Later we fix these gaps. Use 5-second glue over the perimeter of the parts.
Step 4 Sanding main parts
For this step we need rough sanding paper (180 grit). Our main goal to remove all 3d printing scratches, defects and do the pieces as smooth as possible. More you do sanding work – better the model looks. I use Dremel tool and sanding paper, Dremel just makes the process a faster. We need to sand all over the model and especially – gaps we glued. After checking the model for the support that can still be here after 1st step. Sanding paper can get to such places where Dremel can not.
Step 5 Glue the model
Glue 2 front parts (front and middle parts) and back parts (handle and middle parts) Do not glue the whole gun now, as we still have to put inside mechanism and barrel with the bullet. Take metal small stick. Put mechanism inside the middle part connected to fronts. After, put in the stick. Stick should hold the mechanism in middle part of the gun. We have 2 pieces with already installed mechanism inside, but it still can fell out. To continue the process, glue as we did in step 2 and 3 front and back parts. Now we have fully assembled Last Word prop with the mechanism.
Step 6 Filling all gaps
In this step we use the gap filling paste to fill the gaps we have in our model. We have just a handle part on the left – I will show you how to use filling gap paster, this is just an example. Need about 4-6 hours to become dry. We have already finished part at the middle – that is how it should look at the end. And we have a gun on the right – already with filling paste that is dry enough and ready to work with, but not yet finished. I will also show you how to finish it. So we need to cover with the filling paste all the gaps around the model.
Step 7 Smoothing step
We have to smooth all the fflling paste. Do it only after it is dry enough. Different pastes have different time for drying. Make sure you know what time you need before you start smoothing. The Last Word on the right is dried and we need to make it same as the left one. We have to sand the prop until the model becomes clean and all gaps are filled. Luckily filling paste sands very well and fast. Use sanding paper both grits (180 and 360) and Dremel tool if you want.
Step 8 Finish
Use soft sanding paper (360 grit) to finish the prop and make it as smooth as possible. Do it all over the gun. At the end use screwdriver to attach the barrel to the mechanism.