Acrylic fabrication questions? I can help!

[m1k3]

^^ thejuggernaut I took your "donut" idea and simplified it. Cutting a square is much easier than cutting a circle

I ended up doing the donuts on mine. The inside hole, I used a hole saw in a piece of MDF to make a pattern and routed the hole into the acrylic. Then I used double sided stick tape and attached the b-nut from my bulkhead centered over the inside hole and used a flush trim bit to make a perfect donut. Or as perfect as I could make it anyway. I think it turned out pretty nice. I was out of black acrylic at that point and used a piece of clear for the donut spacers.

 

[WmTasker]

I am guessing that this will work since it says marine epoxy and has a picture of an aquarium on it.

 

[thejuggernaut]

I ended up doing the donuts on mine. The inside hole, I used a hole saw in a piece of MDF to make a pattern and routed the hole into the acrylic. Then I used double sided stick tape and attached the b-nut from my bulkhead centered over the inside hole and used a flush trim bit to make a perfect donut. Or as perfect as I could make it anyway. I think it turned out pretty nice. I was out of black acrylic at that point and used a piece of clear for the donut spacers.

Cool, what was the diameter thickness of the donut? Did the solvent wick all the way through it?

 

[Floyd R Turbo]

I am guessing that this will work since it says marine epoxy and has a picture of an aquarium on it.

No!!! "Marine" means for boats on the ocean, not reef tanks. Don't use that! I believe it has metal in it.

There is a fair amount of debate on what is "reef safe epoxy" but most of these are around the standard 5, 10, 15 minute stuff, and most arguments come down to the fact that after the curing process is complete, they don't react to anything and are pretty safe to use.

I would try superglue first, on a test piece.

 

[WmTasker]

Well I guess I'm going to Menards to try and find something then. I wish I could just figure out what other people have used. I just haven't found a pic or a brand that they say that they have specifically used.

 

[m1k3]

Cool, what was the diameter thickness of the donut? Did the solvent wick all the way through it?

Thickness was 1/4" or .23whatever it actually is for acrylic. Inner diameter is 2-7/8" and the outer diameter was whatever the b-nut outer diameter is on a 2" bulkhead. I think about 3-1/2" or so. I am in Mexico and it is installed on the tank now anyway. The solvent did wick all the way through (WO4) with a few micro bubbles. I did not use pins.

 

[thejuggernaut]

Cool, I guess it would wick all the way through, considering skilled fabricators and solvent weld 2" acrylic.

 

[Floyd R Turbo]

Doing laminate joints without pins is usually OK because they aren't structural & don't need to be water-tight. The rings/extenders on the BA box are an exception though. I didn't use pins on mine either, I just 'drew' a ring of solvent and then laid the material down on it, which gives usually the same result. Wicking it in using capillary action without pins is hit or hiss, somtimes it will leave a huge swath of air trapped with solvent all around, and sometimes this can actually leak.

Cool, I guess it would wick all the way through, considering skilled fabricators and solvent weld 2" acrylic.

...but they use pins, for sure. Any tank built using capillary welds is playing with fire. no soak time = no bite = weak joint. I've seen Youtube videos of people who do it but that doesn't mean it's right or safe.

 

[m1k3]

Doing laminate joints without pins is usually OK because they aren't structural & don't need to be water-tight. The rings/extenders on the BA box are an exception though. I didn't use pins on mine either, I just 'drew' a ring of solvent and then laid the material down on it, which gives usually the same result. Wicking it in using capillary action without pins is hit or hiss, somtimes it will leave a huge swath of air trapped with solvent all around, and sometimes this can actually leak.

No argument there. I don't have much acrylic experience, but thought process for not pinning it were:

The inside diameter of the holes matched perfectly and I wasn't confident I could kept it that way while pulling pins.

The joint is under constant compression from the b-nut instead of tension or shear force as would be the case for a tank seam.

It was a pretty narrow ring, about 1/2" or slightly more. Did not foresee an issue getting it to wick. Full disclosure: one wicked perfectly, the other did about 90% of the circumference. That second one had a good bond all the way around the outer diameter so I just hit with a little solvent from the inner diameter and filled that bubble. I like floyd's idea of putting down a circle of solvent and squishing it out. I think that would have been easier/stronger.

I was out of black acrylic. If I did not use clear for the ring I probably would have pinned it.

 

[JAGarciaOfTroy]

Hey guys,

Quick question regarding any official literature that may have come out of this thread. I know it has been split multiple times but the originator Acrylicman had mentioned early on that he was compiling some EBooks on the topic of DIY acrylic fabrication. I haven't had time to go back over all of the previous splits and was wondering if anything ever came of it. I am very interested in purchasing any literature or videos on the topic.
Thank you for your time.
Alex

 

[Floyd R Turbo]

m1k3, the joint may be under constant compression but that is not the issue because there is now structural component. The issue is that the 2 panes must be sealed 100% to prevent leakage. When you have a bulkhead holding on an internal and external box with glass in the middle, you have to put the gaskets on either side of the glass between the 2 boxes. You don't *have* to put gaskets on the insides of both boxes (on the flange and the nut). The reason is that you don't really care if water gets between the nut and the internal box and works it's way through to the external box via the space between the hole in the glass and the bulkhead that passes through it, because it can't get out from between the glass and either box, it can only get out via the gap between the bulkhead flange and the external box, which is under water.

If you have a extender piece laminated on top of the external box to push it out past the tank rim, the joint between these two is potentially exposed to water, because it is within the sealed path. If it is not 100% sealed all the way around, you have a potential leak point.

For a small lamination like this, this is why I described the process in post 4116

How you do it is you take WO #3 or #4 or even #16, lay the back panel face up on a table (preferrably, on a board with foam strips, you'll see why) and then essentially draw a circle around the 2 pass-through holes with the solvent. This is all you *really* need to bond, the panel is not structural but you need it to be watertight, so you need a full seal around the hole between the panels. Theoretically you could just silicone and clamp also, again, because it's not structural and doesn't have to be. Anyways, once you have the solvent in place (and you can add more all over the area that will be touching together) you will want to start with the 1/4" piece at a slight angle, touching on one edge, and then hold it there with one hand while you lower the piece down and make contact from one side to the other. It's a form of art to do this and make it bubble free. It's a form of art to do this and not make it look like total %$#% really. But generally it doesn't mater how it looks.

Make sure the holes and edges line up and you are good to go. Come to think of it, it's better to just cut & trim the holes, then bond, then after it cures, flush trim the other 3 edges, that way the will all line up for sure.

Also, technically, you only "need" the gasket between the outside glass and the external box to avoid any leaking. But, if you don't have a seal between the internal box and the glass, and you have a long-term power outage, you could theoretically have a slow drain effect between the glass and the internal box, letting water by and down the drain, which would eventually drain your tank down to the lowest point of the hole in the glass. Add $3 gasket and you avoid this potential scenario.

Quick question regarding any official literature that may have come out of this thread. I know it has been split multiple times but the originator Acrylicman had mentioned early on that he was compiling some EBooks on the topic of DIY acrylic fabrication. I haven't had time to go back over all of the previous splits and was wondering if anything ever came of it.

Nope he disappeared, no idea what happened to his purported books. There are a few referenced in this thread within the last few months. One made by Plexiglas, there's one you can buy from Craftics, I think one from Cyro. But really if you take the time an read this entire thread from start to finish, it's the best resource and costs you nothing. It just takes time to weed through the repeated questions, as it every mega thread. I actually did this and copy/pasted a bunch of it and categorized it for my purposes, one day I'll go through it all again now that I know what I'm doing and maybe I'll put together a summary. In my copious free time

 

[m1k3]

Floyd, as stated, I did have a good bond around the entire outer diameter. For probably half the thickness. I had a void on one half of the contact area which I was able to fill from the inner diameter before the solvent got the joint set. I realize it's not a structural joint, that was part of my justification for not using pins on this application. My entire post was that I was not concerned about the strength of the joint. Just the position of the donut and its ability to hold water relative to the external box.

I am well aware of where the gaskets go [emoji106] , I have one on each side of the glass. Two total per bulkhead. None inside either box.

We are both saying the same thing.

I made one big mistake in the making of this overflow. I chose not to trap the bulkheads so they would need to be cut down. No big deal I cut the template in half that I used to router the holes in the boxes and slid both pieces over the bulkhead trapping one against the flag and the other midway out with a thin piece of plywood held against it. I was able to the ride a bandsaw blade against that piece of plywood and get a nice clean cut. Unfortunately. ... measure twice cut once... measure once cut twice with a two day delay waiting on new bulkheads cause I cut them too short. [emoji1]

 

[Floyd R Turbo]

Yep I thought you had it all I was just filling in the blanks in case someone else might be following along and could have missed the original post where I mentioned the lamination process.

 

[tidus10]

im really sorry but there was WAAAY too much to read.. and maybe im over simplifying this...

Ccant i get 5 pieces of acrylic and find this bonding agent and stick them together? What is the same of that bonding agent?

If i get 5 12"x12" 1/4" thick acrylic and lay the solvent between the pieces isnt that all you have to do?

 

[Floyd R Turbo]

Put simply, yes. Weld-on is the brand name of the product. #3 is liquid-thin, #4 is a bit less thin and gives you more working time. #16 is a gel version but is really not good for structural joints, just repairs.

You are actually solvent welding the material together, not gluing. The welding process actually melts/dissolves the material, and when it dries, the two pieces become one. Because the solvent evaporates as it dries and the joint cures, you have to ensure that the 2 pieces of material fit together pretty well - the cut edge of one piece must be pretty much straight and square so that it makes full contact or else you will end up with air bubbles in the joint.

If you go back to some of my posts made within the last few months, I gave a quick run-down of the process, that might help you understand it a bit better. Start in January of this year and go forward.

 

[thejuggernaut]

Well I feel pretty confident that I have the tools and the know how to make an overflow and ATS now. I ordered a sheet of clear and a sheet of black plex g. I'm going to go pick it up tomorrow. I plan on drilling one of the 120s I have in my garage for the overflow as my test bed to get me back in the hobby after a few years off. Hopefully I'll fill this one up and in a year to 18 months need a bigger tank! I'll keep ya'll posted on how it goes!

 

[thejuggernaut]

Well I got my acrylic today, and he was nice enough to give me some 1/4 scrap and a 1" thick 60" X 2" piece to use as a straight edge on my router and for doing rough cuts. I was pretty stoked about that. However they were out of weldon 4 and only had 27 gauge squeeze bottles. I'm going to call around tomorrow and see if I can source a good supply of those close to me. I think I want 22 and 16 gauge 2 oz bottles. Does that sound consistent with what everyone else is using?

 

[WmTasker]

I decided to go the best route and just got some Weldon 16 to put back together my InTank media rack. Any suggestion for the best way to apply it. I'm afraid I might get to much on if I try to squeeze it from the tube.

 

[Floyd R Turbo]

Well I got my acrylic today, and he was nice enough to give me some 1/4 scrap and a 1" thick 60" X 2" piece to use as a straight edge on my router and for doing rough cuts. I was pretty stoked about that. However they were out of weldon 4 and only had 27 gauge squeeze bottles. I'm going to call around tomorrow and see if I can source a good supply of those close to me. I think I want 22 and 16 gauge 2 oz bottles. Does that sound consistent with what everyone else is using?

www.craftics.net is the best place to get the squeeze bottles. you will have a pretty hard time finding weld-on locally. It's just not in high demand I guess so you pretty much have to order it. I have trouble finding it in the metropolis that is Des Moines so I have to get it online. I use Methylene Chloride with 5% glacial Acetic that I mix myself tho so I haven't looked around lately. I think my local plastics shop carries the craftics version of #4 and #16

For most projects I use the 1/2 oz bottle and the #22 needle. I break out the 2 oz and #16 for the long joints.

The #16 needle is kinda scary to work with the first time. You need to squeeze the bottle pretty goo when using a #22 needle, but with the #16 is dumps out on it's own pretty darn fast. So fill the bottle 3/4 of the way, squeeze out the air, invert and release so it starts sucking air in and position the tip of the bottle at the start of the joint, and then before all bottle has returned back to it's full shape, give it a little pressure and get ready to move fast. When you get to the end of the joint, release your pressure and pull the bottle back from the joint.

Also because the needle is firm, you need to make sure your pins are in there good, because you will knock them out as you pass them if they aren't. Which is why I only use it on long joints, or more accurately, joints where the top part is heavy enough to keep the pins in place.

I decided to go the best route and just got some Weldon 16 to put back together my InTank media rack. Any suggestion for the best way to apply it. I'm afraid I might get to much on if I try to squeeze it from the tube.

oops I forgot to reply

you don't need much, just a really thin bead. The stuff is goopy and stringy so work fast, have a paper towel ready to put the tube on while you position things. It dries to a paper-thin profile, so any goops you get anywhere will dry up. But don't try to clean gobs off when it's still wet, all you will do it smear it all over. Wait until it gets tacky and starts to harden, and then slice it off with a razor blade before it gets really hard. Or just wait and sand it off after it dries

 

[thejuggernaut]

Well all three plastics places I called locally have weld on 4 in the 4 oz cans, but they all only have the 25 gauge needles and one guy had 16 gauge. You ever use the smaller gauge or are they really too small for welding 1/4" material