Tube plugs

[joseph10s]

I was doing some casting this weekend and nearly all of the 14 blanks had a large slug of resin inside the tube after casting. I glued corks into both ends but am thinking that I used too much pressure. I think I was at 50psi. What does everyone else cast at?

Also, I was looking through some old posts and found a topic on silicon plugs but no reported results. Has anyone been using those instead of corks?

I was thinking that I could just fill the entire tube with something and wouldn't have to worry about the seal as much. I was trying to think of something universal that would fit in all tube sizes. One of the things I came up with (and probably read somewhere else but don't remember) was nails cut to a universal length. Any thoughts? I think others mentioned some type of putty. Sounds messy though.

Here is a picture of the PR plugs I've been dealing with.

I was also thinking I could just put these back in the tubes before I cast. I just don't know...

 

[Darley]

Joseph do a search about casting or snake skin casting, Don Ward perfect the problem of tubes ends, try to read Don tutorial on snake skin casting this will answer to your question, cast at 20 to 25 PSI

 

[karlkuehn]

Shove the tube all the way through a potato and trim the ends. I'll have to try that and see if it works, I'm just getting ready to cast some pre-drilled blanks myself.

 

[rherrell]

I use med. ca to glue the corks. When it's dry I use the disk sander to sand them down to 1/8" from the tube. I then put some thin ca on them. I cast at 50lbs. also and have never had a leak.
Hope this helps.

 

[Blind_Squirrel]

I hate the clean up involved with gluing the tubes in. I have been searching for an alternate solution. I think I may have come up with one. I microwave a candle for a minute or so, then dip the corks in wax. When putting the cork in the tube make sure you get it WAY in there and clean off all of the excess wax. I have cast as high as 60 psi without a leak.

 

[Sylvanite]

I've tried filling the tube with modeling clay before corking. That worked well except that I overfilled and some clay escaped from the ends under pressure.

I've also tried turning delrin rods down to the tube interior diameter. I figured they'd be reusable. I went for a snug fit, however, and later couldn't get them out.

I plan to try the delring again with a bit more play, and also try clay-filling with delrin end caps.

 

[joseph10s]

Thanks for all the replies. It is encouraging to hear that others are casting at the high pressure with no issues. I think I may try a few of the ideas suggested, wax and delrin, and see how they go.

Thanks again.

 

[rtrimyer]

I do not cast yet, my wife said I am not allowed to spend more money yet... I was thinking that the spray foam insulation that you can buy at Home Depot should work, that tube is not too big, and you can trim off the excess when it dries. It should be fairly easy to ream out with a small drill bit or even a barrel trimmer. Just a thought, if it sounds too weird just tell me.

Thank you

 

[Stevej72]

I haven't had any leakage since I started using rubber stoppers instead of cork, also they are somewhat cheaper than cork. Just a drop or two of medium CA, press the stopper in and hold until it sets.

 

[LEAP]

Where are you getting your rubber stoppers?

 

[Stevej72]

I get them at the hardware store, right beside the corks.

 

[bruce119]

I was wondering what do you guys use to support your tubes to stay centered in the mold.

This what I do I use balsa. I got a lot from my modeling days. I take a large soft piece. take a pen tube sharpen the end push it into the balsa then just push the balsa out with a mandrel. Whala a perfect balsa dowel. Then I med. CA it in the tube. Then to support the ends I cut sheet balsa to fit the mold then use a tube to punch out a hole and CA the whole thing together. I seldom get a leak and it is usually easy to clean out. And I cast at 50psi.

Just wanted to share what I do and perhaps find a better way.

I also started a new thread so outher could see and relpy to this.