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20090505 Tuesday May 05, 2009
Mold is done, die is cast

As I kept on spending money to make a mold of the w2100z CPU retainer bracket, I came to the realization that I wanted to make a mold more than I wanted a silent PC. It is that simple. I came up with a cheaper method to extend the original brackets, and I may end up falling back on that.

But that is later, for now we should concentrate on my travel to get a mold.

I'd have to say the biggest non-lethal mistake I made on this project was assuming that since the retainer was pretty plain and out of sight, I didn't have to be as careful as I needed to be with making say a figurine. I didn't always measure twice, which can be seen in my choice of using a sandwich container for my mold box:

Sandwich to the rescue!

I didn't make sure that there was a 1/4-1/2 inch space at the top and I ended up having too much extra space. Also, an expensive lesson here is that all of that dead space in the middle of the bracket needs to be filled with mold material. If I had placed an object there to take up room, I would have had a donut shaped mold and saved some money. Ehh, I don't know how easy it would have been to work with that mold!

I really should have taken the time to smooth out the layer of clay. That really ended up hurting me when I casted a bracket. But that all is in the future. Right now we can see that I've run out of mold material:

Need more goo!

I had calculated the amount of product needed and was dismayed to realize that just for the top portion it was more than the starter kit provided. BTW - the kit tells you how much base you have, but it doesn't tell you how much of the activant you got or how much the base container weighed.

Speaking of weight, I needed to buy a gram scale:

Scale!

I felt weird walking through a store looking for a gram scale, syringes, and disposable plastic gloves. I.e., I realized what else that stuff could be used for!

Anyway, the scale was a wise investment and I can now use it on the expense reports I need to send in (i.e., do I need one stamp or two?). Also, I flashed back to HS Chemistry. I must have been paying attention at some point, because I knew to offset the weight of my containers.

A day later, and I have some cheesecake with a nice blue playdo crust:

The top is done

And if we flip it over, we see the next issue:

Who has my can-opener?

I need to cut open the sandwich container. I realized this before I added the mold material, but went on with it anyway. I was having a tough time figuring out what to use as my mold box (did I mention that this was my very first attempt to make a mold?). You can see another problem, I didn't make sure to get a good seal with the clay against the wall.

Once all of the clay, well most of it, is removed, we can see the bottom part:

Bottom

I would end up getting more of the clay removed, but I mainly concentrated on the stuff on the retainer. I had meant to leave some on the inside corners of it, but decided not to do so. My other idea was to later add some milliput and shape it as needed.

I didn't capture my next mistake - which was probably the worst. I forgot to add the mold release before I started to pour in the bottom mold. I caught this after I had started, but before the mold really set. I poured out the product, scraped it down, and added some release agent. I was already screwed and not inclined to buy another $29 bottle of mold material. I had the milliput in mind already.

Also, as can be seen here, I didn't have enough clearance on the bottom:

Oh no, its Mr. Bill

I used duct tape to build up the side. That actually worked out okay.

After I pulled out the set mold, you can see there really isn't a line to separate the two halves:

No tan line!

I took a line and cut along the clay residue. Another lesson is that I should have marked the line on the clay box. Here we can see the original part, rescued from its early grave:

Free at last!

And here we can see the mold:

Rugged terrain

I set the mold and it is alive I tell you! Alive!

My clone

But it does need some surgery:

Surgeon wanted

At first I thought my mold was bad, but then I realized that it was simply an air bubble. I got rushed at the end, resin was pouring out of the bottom of the mold. I had been burping it, but I didn't get enough product up to the top corners. Some vent holes there might have done wonders.

The main problem with the resulting part is that I don't think it is strong enough. I'll need to recast and add some fillers. I read somewhere that nylon string strands would work. But I need to confirm that.

But what I can do with this part is fit it perfectly to the fan clip and the motherboard. I can use milliput to reshape. And once I have that in order, I can either create a new mold (wouldn't be prudent at this juncture) or have an easy way to reshape strengthened clones or the originals.

It was fun and I'm amazed that with as many things I did wrong, I got close to what I wanted. The unit cost can only go down and I'm pretty sure I can get a stronger retainer!


Originally posted on Kool Aid Served Daily
Copyright (C) 2009, Kool Aid Served Daily

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