Acrylic seam repair

[shermoen]

Soooooooo, I bought this tank for 80 bucks i think (it was last year). I was planning on setting it up this year as it needed the acrylic polished and I was not doing that over the winter.

Previous owner had it setup for over a year I believe until he upgraded. When I purchased I didn't notice it had a seam that looked stressed. Thankfully another reefer on reef2reef noticed it!

I have not filled it to see if it will leaks. I think I'm gonna try and repair it anyways and will then leak test it. Unless otherwise advised.

I found an old forum that discussed using square or triangle acrylic rod in the corners to repair exactly what is happening in this tank. I figure I can give that a shot since I'm pretty handy.

I've found the acrylic rod but, my question is do I have to use clear acrylic or could I use a colored acrylic? I think it would look pretty cool with a blue or green or yellow rod in the corners. Im not schooled enough in acrylic so don't know it the weldon process would work the same with the colored rod compared to the clear.

 

[cdemoss01]

Keep us updated.

 

[albano]

In the past 20 years, I’ve had at least 5 custom acrylic tanks built (130, 170, 200, 450 & 500g) all with the added triangular corners. Wouldn’t want a tank without them… as a bonus, most magnet cleaners will clean around the corners!

I would suggest clear acrylic, IMO colors would make it look cheap/toyish !

 

[shermoen]

In the past 20 years, I’ve had at least 5 custom acrylic tanks built (130, 170, 200, 450 & 500g) all with the added triangular corners. Wouldn’t want a tank without them… as a bonus, most magnet cleaners will clean around the corners!

I would suggest clear acrylic, IMO colors would make it look cheap/toyish !

I understand your opinion on this idea of being cheap/toyish, but I thought it would look like a rave with all the glowing corals and the corners of the tank as well!

Anyway, doesnt really answer my question as to if the colored rods will weldon just the same as clear.

 

[UncommonSense]

I understand your opinion on this idea of being cheap/toyish, but I thought it would look like a rave with all the glowing corals and the corners of the tank as well!

Anyway, doesnt really answer my question as to if the colored rods will weldon just the same as clear.

All cell cast acrylic should weld similarly, regardless of color!

I’m glad we spotted those bubbles prior!

Consider doing the bottom perimeter seam with reinforcements too; it's kinda a case of “while we’re in there”

Acrylic solvent welding is a bit of an art form… I’m definitely still learning the ropes! — I recommend seeing if you can get some free acrylic scrap from your local plastic fabrication shop to practice welding on!

Also, my LFS wants me to try this technique on a few ancient sumps next month… keep us posted on results? I know I’m curious!

 

[shermoen]

All cell cast acrylic should weld similarly, regardless of color!

I’m glad we spotted those bubbles prior!

Consider doing the bottom perimeter seam with reinforcements too; it's kinda a case of “while we’re in there”

Acrylic solvent welding is a bit of an art form… I’m definitely still learning the ropes! — I recommend seeing if you can get some free acrylic scrap from your local plastic fabrication shop to practice welding on!

Also, my LFS wants me to try this technique on a few ancient sumps next month… keep us posted on results? I know I’m curious!

Hey buddy! Good eye on you, and I'm really exited to try this out. Found an old thread by a gentleman named Bob Fenner, whom discusse this topic alot on a website called wetwebmedia.com.

Thanks for the input!

 

[UncommonSense]

Hey buddy! Good eye on you, and I'm really exited to try this out. Found an old thread by a gentleman named Bob Fenner, whom discusse this topic alot on a website called wetwebmedia.com.

Thanks for the input!

Oh yeah!! I remember that website! — I’ll check it out!

Haha this eye has been trained by years of disappointments! — like you said, better than a flooded house!

Of course! I’m also looking at other solvents for acrylic welding which aren’t as volatile, and offer a longer working time than 2-3mins!

 

[shermoen]

Oh yeah!! I remember that website! — I’ll check it out!

Haha this eye has been trained by years of disappointments! — like you said, better than a flooded house!

Of course! I’m also looking at other solvents for acrylic welding which aren’t as volatile, and offer a longer working time than 2-3mins!

Im actually looking forward to this project. After the mini crash I had. I still figure it's a good time to start getting ready for my next build and this will be a great project.

This one will get me out of my comfort zone since I'm doing everything completely different than normal (Acrylic tank opposed to glass, closed loop opposed to powerheads, metal halide opposed to Led).
I'll setup a build thread once I get it going.

From my research so far weldon 16 is the way to go when installing the corner rods, and for this project 1/4" is supposedly enough. I am wanting to do triangle rod to make it flush with the inside corners but some have stated they sometimes dont fit completely flush because it's extruded, so may cause small gaps between the rod and tank.

Please let me know how your trials and research go looking into other solvents. I look forward to your advice and input.

By the way here are the posts I've been sifting through.

FAQs on Acrylic Aquarium Repair and Modifications 1

 

[UncommonSense]

This one will get me out of my comfort zone since I'm doing everything completely different than normal (Acrylic tank opposed to glass, closed loop opposed to powerheads, metal halide opposed to Led).
I'll setup a build thread once I get it going.

I think you’re going to really like this setup if you can get it up and running!

From my research so far weldon 16 is the way to go when installing the corner rods, and for this project 1/4" is supposedly enough. I am wanting to do triangle rod to make it flush with the inside corners but some have stated they sometimes dont fit completely flush because it's extruded, so may cause small gaps between the rod and tank.

I’ve found that acrylic prep is 99% of the work when solvent welding; you can always sand the rods down to be perfect right angles! (I’m actually planning on making mine out of an old 3/8” acrylic tank… cell cast material vs. extruded; just pass a pane through the table saw a few times to make some triangle rods, then sand/prep!) — here’s the guide I used to successfully do my first watertight weld!

Acrylic Fabrication Q & A

I am very active on a similar mega-thread elsewhere but I couldn't find an active one here on R2R. @Troylee started the Acrylic 101!!!!! thread a while back, but it doesn't look like he's very active here anymore. Maybe this thread will suck him back in, he has great advice. SHORT CUT LIST...

www.reef2reef.com

Please let me know how your trials and research go looking into other solvents. I look forward to your advice and input.

I’ll keep you posted! There are a ton of different ways, apparently! Haha one person in another country posted here on R2R recently saying they repaired a broken acrylic pipe with freakin Chloroform!!!

By the way here are the posts I've been sifting through.

Awesome! I’ll be digging through this too, thanks for the link!

 

[shermoen]

Haha one person in another country posted here on R2R recently saying they repaired a broken acrylic pipe with freakin Chloroform!!!

Wow thats interesting. I hope they didn't pass out while fixing it!!

 

[UncommonSense]

Wow thats interesting. I hope they didn't pass out while fixing it!!

Haha right?? It was that octo Skimmer thread IIRC!

 

[fish_collector]

I’ve found that acrylic prep is 99% of the work when solvent welding; you can always sand the rods down to be perfect right angles! (I’m actually planning on making mine out of an old 3/8” acrylic tank… cell cast material vs. extruded; just pass a pane through the table saw a few times to make some triangle rods, then sand/prep!)

As someone who has been using their table saw for 20 years for things, I would never have suggested trying to cut triangle shaped sticks with it. The possibility of a kickback and/or binding the piece against the fence, even keeping your work piece against the fence while pushing it through would be a no-go for me. Cutting acrylic with a table saw is also something that must be done all in one pass with no pause, the acrylic gets gummed up on the blade and will start to melt the piece as you cut it if you slow down or pause at all. The finish a table saw leaves on acrylic is hardly good enough to solvent weld, edges are typically finished with a spiral router bit. You can just as easily find them in triangle shaped sticks already, amazon probably.

Personally, I don't think acrylic seam repair will come out as nice as one would think it would. Solvent welding a stick into a corner with no bubbles is hard to do. The corner isn't likely to be a perfect 90 and it will be hard to get a bond without bubbles. The pin method is also hard to implement because of 2 angles that need to be softened at the same time before pins are pulled. Id suggest using #16 from the tube, that would give you some dwell time and allow it to fill better should the filler stick not be 100% in contact with both angles of the corner. It may not come out as clean as one would like but at least it would strengthen the corner of a seam that has delam.

Id set the tank up at an angle and secure it somehow so the seam to be repaired is pointed straight up. Then Id apply #16 as a healthy bead into seam, then press the filler stick into it. It might even be advantageous to apply #16 to the stick as well but remember you've got about 5 seconds before your solvent will skin over so it's likely you may not get your piece into position fast enough. A nice fillet into the seam may be enough to have some squeeze out by itself. Id also suggest masking off the rest of the tank as you don't want to get any solvent on the viewing panels.

If you've never done work with acrylic before, what you are going to try to do is about a 9 on a scale of 1-10 with 10 being the most difficult. It's not impossible but I'm just giving you a primer of what you're up against. Practice a few times before you attempt the seam repair.

Sorry for the pessimism. I don't want to see you ruin a tank that may have been salvaged by someone who had experience doing it.

 

[UncommonSense]

As someone who has been using their table saw for 20 years for things, I would never have suggested trying to cut triangle shaped sticks with it. The possibility of a kickback and/or binding the piece against the fence, even keeping your work piece against the fence while pushing it through would be a no-go for me. Cutting acrylic with a table saw is also something that must be done all in one pass with no pause, the acrylic gets gummed up on the blade and will start to melt the piece as you cut it if you slow down or pause at all.

I also have a tad over two decades of experience on my saw… I’ve cut 1/2” thick acrylic bevel strips regularly, among other wild shapes…

What sort of blades were you using? Presumably not a triple chip style?

For someone with cheap tools and minimal experience; this claim is indeed true…

However, actual craftsman with significant tool investments make cuts like these on a daily basis…

 

[shermoen]

Id set the tank up at an angle and secure it somehow so the seam to be repaired is pointed straight up.

Yes, I thought it would be a good idea to make a stand that the tank would sit in as I made my repairs. I would have it to where the corner i am working on is pointed down. Thanks for confirming this thought for me.

If you've never done work with acrylic before, what you are going to try to do is about a 9 on a scale of 1-10 with 10 being the most difficult. It's not impossible but I'm just giving you a primer of what you're up against. Practice a few times before you attempt the seam repair.

Sorry for the pessimism. I don't want to see you ruin a tank that may have been salvaged by someone who had experience doing it.

I have very minimal acrylic work. A very basic understanding after a few basic welds on a previous project, as well as hours of research at this point.
No worries about the pessimism, I'm pretty pessimistic as well but I'm pretty handy and not to worried about a perfect look. If by chance it gets screwed up I'm sure the Lord will have other plans for it!

 

[fish_collector]

I also have a tad over two decades of experience on my saw… I’ve cut 1/2” thick acrylic bevel strips regularly, among other wild shapes…

What sort of blades were you using? Presumably not a triple chip style?

For someone with cheap tools and minimal experience; this claim is indeed true…

However, actual craftsman with significant tool investments make cuts like these on a daily basis…

Not going to disagree with you at all. I feel those kind of cuts with acrylic on a TS are dangerous no matter if it is a budget saw or a 5hp SawStop. I wouldn't expect anyone except a cabinetmaker to be able to cut something like that with any success. I'm not calling you out on it, I'm saying I wouldn't recommend doing it. If you can do it, good for you.

And Fwiw, I have a vintage Ridgid 10" saw running on 220v, cast iron top, mobile base, ShopFox T Square fence and a 50" extension to the right of the blade and an outfeed table. I don't change blades very often, most of the time I use a 60t Forest laminate blade for everything except ripping plywood. I don't care for any higher tooth counts the cut finish isn't much better. Besides when I do acrylic work I cut oversize on the TS and use the router table to bring it into dimension, or clamp on a straight edge and route it by hand. I'm neither a cabinetmaker or signmaker.