Hi
@Floyd R Turbo
could you please validate my design? Is only the cover and I’m planning to use 5/8” thick
Looks good to me
After a few tries using the advanced search option to find a conversation that probably already exists I figured I’d just start posting, it’s probably faster.
These air pockets are killin’ Me! Edges are square, pins method of course, I used feeler gauges to get the gap consistent to within like .004 across the entire joint, I wiped both surfaces down with denatured alcohol, pins are 28 gauge, etc.. I didn’t blow the joint out but I do all of my fitting first including all the feeler gauge work and then break it back down to clean with alcohol then set it back up to run solvent which is weld on 4.
This is 3/4” thick Acrylite.
Thanks in advance.
What's the painters tape for? I don't use this, never have. 1) on the exterior edge, you are going to flush trim this off so you generally don't care, but also I never have an issue with dripping due to capillary action (the solvent wicks into the joint instead of running out) 2) on the inside you don't want anything that would cause the solvent to wick away from the joint, or you won't get a fillet on the inside, so the tape on the flat piece might actually cause wicking under the tape resulting in the problem you might be trying to avoid.
But all of that said, that doesn't explain why you're having this problem in the pic. Not blowing out the joint may cause particles to remain in the joint (dust) that could cause the formation of a bubble, but usually that's a tiny bubble. If I had to guess, you're running the needle ahead of the capillary flow instead of allowing the solvent to wick in ahead of the direction you are moving. That can cause the solvent to get "pushed" into the joint rather than "flowing into it"....it's hard to describe, and hard to catch on video without a helper.
Basically, what you do is start adding the solvent at one end and move the needle slowly and allow the solvent to wick in ahead of the tip of the needle, and it doesn't need to be much. {edit} then once the flow is ahead of the needle, you match the speed of the flow and the needdle. I've let this get as much as 2-3 inches ahead of the needle, so I actually stop applying solvent (in some cases) a full inch from the corner, because the solvent has already beat me there.
What happens if you have a line of solvent flowing out of the needle and then filling in an open joint is you can cause air to get sucked into joint along with the flow of the solvent. If you are adding the solvent in an area that is already filled with solvent, then the you don't have much of a risk of air getting pushed in, and the solvent flows from the application area toward the unfilled gap, because it has no where else to go (and it won't go through the joint to the other side, unless you are squeezing too hard
Also with joints 1/2" and over, I switch to the 16 gauge needle (at least for the top/bottom joints). This takes a deeeeep breath the first time you do it, because you are using a 2 oz bottle and the solvent comes out of there super freakin fast. That's a double edge sword, because while it's really easy to mis-apply the pressure (and blow solvent through the joint) it is also much faster, and on long joints (like the top of bottom joints on a 6 or 8 foot tank) you can get around that entire joint (so, 20 feet of joint) in about 30 seconds. Try that with a 22 gauge needle...but once you get used to it, it's the only way to do these types of joints (thick material and/or long joints)
