Sunday, April 29, 2012

Lots of interesting developments, and more DIY madness.

  Hi again folks.
  Today I am going to explain some things that are going on and that should be having an impact on future projects.
  First, I have been looking into resin casting some things. It seems to be a better medium for some items. So I have constructed a vacuum chamber to de-gas the rubber mold material.

  This is a weak $15 vacuum pump from harbor freight and a couple of 4" PVC pipe sections from Home Depot.  The top gets a piece of thick plexiglas covering the hole so I can look in and see if the silicone is bubbling up or not.

  The end simply unscrews and allows you to place a container holding your silicone for de-gassing.

  Next I needed a pressurized container to reduce air bubbles in the resin while pouring a model. So this time I went to Lowes and they have 6" sections of PVC. I picked up a union and 2 screw cap adapters and made this.


  You can see on the back an air fitting to connect to the air compressor.

  Now, when I was at the store all of these PVC pipes say in large letters-  "NOT FOR PRESSURE".  I am sure this is more of a guideline than a rule. I filled this with 60 PSI and the glue held. However, as a disclaimer I must insist that no one else try this at home. And if you do make sure you have a good regulator on your air supply. It would sting a bit to have this thing explode and impale plastic bits into my body.
  So for less than $100 I am ready to look into resin casting.
  Now I need to play around and make some masters too. For this I was counting on 3d printing.


  I told you before about my problems with shapeways and the lumpy stuff they ship you.  I actually see people selling stuff direct from shapeways and this amazes me. First of all it is REALLY costly and on top of that it is super crappy.
  This tank was printed out by another company-and it is very smooth and ready to use. It was Vision Proto in Texas that did it. The owner called and talked to me and we worked out any problems. This tank however is too big. And that is the real problem I keep running into. Something looks good on screen and it turns out to be quite different when you hold it in your hands. And this is what keeps me from making some of the molds I want in plastic. It is a waste to run 200 hours of machining and then find out the women are too thin.  So I want to get most things printed first to determine suitability for production.
  And here is another problem. Getting a tank like this printed is going to run $60-90 depending on how hollow you make it and how big it is. And then it turns out to be not what you expected. So I have to re-size and re-spend. Not what I was planning.
  And that brings me to my ultimate solution. I have ordered a 3D printer. It is one of the budget models but it will allow me to check for fitment and scale on everything before I commit to machining any molds and it will possibly allow me to make masters for resin casting. If my budget machine is too rough for this I will have to spend for the better quality out put, but I think I can play around and get something usable. It has a 6" square build platform so that will be the limitation.  I ordered the Solidoodle machine. At $500 it is the lowest priced 3d printer I have found. There is an 8 week waiting period.  I will offer a full review and pics of what I print out after I get it.
   I have to thank my friend Chris who has explained all about resin casting to me. He has made these hay barriers and I am adding them to the store to sell for him. I painted up a batch and they look quite nice. They will be made by him but stocked in my little warehouse. (OK, it is a shelf from Ace Hardware, but it works)

  Which brings me to the last bit of news. I have been looking for some die cast vehicles to steal parts off of. As I explored it occurred to me that a lot of these would look great for 28mm wargame scenery. I have always thought that every urban battlefield would be littered with wrecks.  I looked at Lucky Joes blog and he is making use of them quite nicely.  http://ljshobbyspot.blogspot.com/

  As soon as I get them in I will be adding some 1/43 scale vehicles to the store. I plan to order a few to see how they go. Mostly I am looking for older vehicles that would look good in a WW2 or sci-fi "grimdark" world. Or maybe post zombie uprising.  There are a couple of diorama pieces I am going to sell also. 
  This is more of my not very smart way of doing business. If I think it is cool I make it or sell it. No market research here!

   Wow, that was a lot of typing. I am going to take a rest and will post more if anything happens.

 



 

2 comments:

  1. Recommend using the stronger schedule 40 or 80 PVC pipe for vacuum or pressure applications.

    ReplyDelete
  2. I read this post. Its just perfect about the creation and the use of the many fields. Thank you so much for the post. Master-Pipe

    ReplyDelete