Hmmm, it’s got me wondering if maybe you could McGyver something up with an old pressure cooker and a vacuum cleaner?
I dunno, just thinking out loud…
Going to the doctor last week and come across a series of about a dozen road signs saying:
“RIGHT LANE ENDS- MERGE LEFT”
And there were about a half-dozen guys in the right lane just driving happy along, not trying to get over into the middle lane at all.
About three miles / five kilos of signs and then the right lane is blocked. So we have all six or so drivers trying to force their way over into the middle lane. Had to hit the brakes to keep from running into a Kia.
I MEAN A DOZEN FRIGGIN’ SIGNS OVER THREE MILES/FIVE KILOS AND YOU COULDN’T FRIGGIN’ READ THEM!?!?!
Nice thought Gam, but it is opposite of what I need. What you are describing is a vacuum chamber. What I really need is pressure going into the pot and that forces the air bubbles to collapse or compress into tiny mostly unseen particles. But some people make pressure pots from pressure cookers. So you are not all that off with it.
Ahhhhhhhh, okay. I was thinking you wanted to lower the pressure to get the bubbles to come out of solution. My mistake!
Nice thought Gam, but it is opposite of what I need. What you are describing is a vacuum chamber. What I really need is pressure going into the pot and that forces the air bubbles to collapse or compress into tiny mostly unseen particles. But some people make pressure pots from pressure cookers. So you are not all that off with it.
Sorry, duplicate post
Its kind of an odd thing. Depending on the type of resin, some people will degass resin that way, as you are thinking but, it will only reduce the bubbles. A pressure pot is the best way to insure a bubble free cast.
A vacuum chamber is most often used to degass silicone. This is where a vacuum chamber shines. The silicone is put into the vaccum chamber and air bubbles are pulled out. Then the silicone is poured for the mold. I didn’t need to do this to make my mold because the silicone did a good job keeping bubbles from the surface layer. Here is the thing though. If I put my mold in a pressure pot to cast my resin, the pressure may force trapped air in the mold to the surface. This then would cause more imperfections in the cast!. I am hoping that I wont have that issue at the lower tank pressure of around 20 lbs. Most people use tank preasures in the 60 to 70 pounds range when working with resin. The jury is out. I will soon find out if the lower pressure will work. Like I said in another post, there are people out there that have tried it at 20 lbs or less and claim the lower pressure works.
So basically Gam, serious casters will degass silicone via a vacuum chamber, make the mold, when the silicone mold is cured, then pour resin into the mold, then place the mold into a pressure pot until the resin cures. This ensures a bubble free cast. The caveat is that the mold has to be designed correctly. A bad mold design will cause airpockets that no pressure pot can overcome. And that might be how I end up with mine. We shall see.
Yes Cliff, they read them. They know exactly what they are doing.
About like the [cnsod] idiots coming on a three lane freeway, jumping to the left lane, only to jump back to the right lane to take the next exit a half mile from where they got on. Just to get there two cars ahead…,.
Yeah, you and Greg are right, I just needed to vent… [6]
Thanks for explaining that. I understand a lot better now where you’re coming from.
I know. I vent all the time when I’m driving. Most of the time my wife quietly tries to ignore me. One of these days, i think she might whack me up the side of the head with something, though.
Just so you know, these merge-morons are one of my favorite ‘venting’ subjects. [:)]
I’m not convinced of that. That would require that they pay attention any further than the sellphone they have pinned to the 12 o’clock position of their steering wheel.
And, @Gamera, it’s funny, my PCP MD office is at the end of a Right Lane Must Exit, which is fine if I’m exiting there. When I need go further than the doc’s office is where I see commercial drivers not bothering to pay atention to he signs, and only lane changing at the last second.
So, traffic right there slows to a crawl at virtually ever hour of he day. Which is why I’m often willing to spend $5-6 to take the toll expressway to go around that traffic embolism. (I once paid near $30 in tolls on that road to get the 20 miles to Fort Worth in only 45 minutes rather than the 2 hours the “freeway” would have required.)
Now, back to Baxter’s build.
Actually, a vaccuum pot can help with casting resin, since the reduced pressure will “draw” the bubbles to the surface. This even works with many molten metals, too. The bowl turning guys I know swear by vaccuum pots for their resin casting, and resin blanks on a lathe really, really, do not “like” bubbles or similar voids in them.
Now, at a c-note per bowl, cobbling up a vaccuum pot for resin blanks is not a big deal, Bakster’s Basement, however, may not have that level of cost or time expenditure available.
Life is complicated that way. Whether we’d prefer it to be so or not.
Yeah it depends on what the end goal is it seems, how you are using it. Turning it on a lathe takes it into different realm. And then the type of resin has to be considered because vacuum pots take time to degass the material, and fast acting resin like I am using doesn’t offer the luxury of time. It would cure before you’d get it out of the pot. I have watched many videos on mold making/resin casting, and processes seem to take on an artform. There are many things to consider. Hence, why I didn’t want to dabble with casting on this project because it’s a time suck, and it surely ended up being that. But the wheel gremlin had different ideas for me and I have no choice but to punch it square in the face. For my purposes, I think a pressure pot is the best option.
I agree with your Captain on paying the toll to escape the extra stress and aggrevation. As I get older I’d rather just get where I’m going even if it costs more.
Bakster best o’ luck and please keep on keeping on keeping us informed. This is all new to me and I’m learning with each post.
Thanks Gam. New to me too but I am learning. Barring any drama this weekend, I will begin getting material for the pressure pot. I am really dreading all this, I just want to build a model. Dang it. Lol.
Where do you go if it dosn’t work Bako? A search for different wheels?
Well Bakster you have finally and convincingly confirmed what we have all surmised for many years. Scale modeling really is a pressure cooker of a hobby![:D]
Hang in there, even though it’s incredibly frustrating you certainly are learning a lot of new skills in a wide variety of areas. What’s that old saying? That which does not kill us…
THAT– is a good question. I have already done an exhaustive search but sometimes, when you least expect it, a situation presents itself. Long story short-- yeah-- that would probably be the plan and taking it back to square one. [:'(]
I am holding hope I will get through this with the PP. [;)]
Laughing! SO TRUE! And I am the poster child for it. You could put my face on a milk carton. [:|]
Thanks for the support!
That is also, SO TRUE. Casting is something I have wanted to learn and yes, I have already learned a bunch. The problem is, I am like a mule. I dig my feet in while the good Lord is pulling my bridle, “Come on you stubborn donkey! I am trying to give you what you want! Move them feet!”
Lol. And the solution may be just feet ahead, a solution of many new doors to walk through.
True! Killed by an exploding pressure pot! LOL
Speaking of a PP. In donkey fashion, kicking and screaming, I am relenting. I decided that I will order a PP verses a DIY. Why? Because for a little over $100 I can repurpose one for casting. It will be safer than a PVC DIY that I was going to do, and really, the cost variance is not that much. In the end I should have a decent setup for future projects. No, it’s not a really well built pot like what I was looking at early on, but this is $300 cheaper, and it will do the job. Many resin casters use this pot.
So that is the latest from Bakoland.
Hee Haw!