This is not to be taken as "mean spirited" in any way , I was there at one time and so were most of us . Your turning technique is probably wrong and that is the biggest problem . You have to learn better control of your tools . The most important technique is to learn to take light CUTS . Your problem is most likely you are addressing the wood with the wrong angle of contact with your tools . A gouge or skew are meant to slice off the surface of the wood or acrylic not to scrape it off . Scraping will tear the fibers of the wood causing tear out and blow outs . A gouge with the sides held straight up (like this "U") or a skew laid flat just scrape the wood off the blank , this will almost always lead to a blow out or a catch and tear out if you are not very careful about how much pressure is being applied .
You need to learn a "Shearing cut" with a gouge or skew , that is to say , you want the tool to contact the wood at an angle (somewhere around 45 degrees) . If you are using a gouge , you want to have the leading edge of the gouge to be lower then the trailing edge and you want the bevel of the gouge to be just about parallel with the wood blank (this is called riding the bevel) . These are difficult techniques to explain but are the fundamental techniques you need to learn .
The leading edge of the gouge is the right top of the "U" shape of the gouge if you are cutting from left to right , imagine the "U" shape of the gouge tilted 45 degrees to the right and the cutting should be done with the bottom of the "U" so that the part of the cutting edge that is contacting the wood is doing so at about the same 45 degree angle . This way the cutting edge will be shearing the wood not scraping it .
Riding the bevel means , the part just below cutting edge (the beveled part) should be almost flat against the blank , then you just lift the handle of the gouge slightly , tilting the cutting edge into the wood ever so slightly so that it starts to take shavings off the blank .
When you get these two angles just right , you will start cutting thin slices off the surface of the blank , if you are doing acrylics (and even some woods) you will be getting very thin ribbons that will shoot off the inside of the gouge . You want these slices or ribbons to be as thin as you can make them .
A poor glue up of the tubes won't help with blow out but I routinely make pens with out tubes and don't get blow outs even on very thin sections of the blanks . It's all a matter of technique , it takes practice but you can do it if you just remember , "Shearing cuts" and "Riding the bevel"
Sharp tools are also important and you should learn to sharpen your tools to make them as sharp as possible to get a good shearing cut . Most carbide cutting tools while very sharp are nothing more then very sharp scrapers and should be avoided until you learn proper tool control .
I hope this helps .