Acrylic fabrication questions? I can help!

[Acrylics]

James,

Thanks for the years of advice you've provided on this forum. I've browsed this thread many times over the years and always learn something.

My issue - I learned the hard way that coraline can etch acrylic if its allowed to remain in place for too long. My tank is 54x48x24 and I've got etching on the lower 2 - 6 inches along the bottom of the tank on three sides.

I assume to do this right the tank should be drained. (Is that correct?) The etching is like a haziness that I can't feel with my fingertips. Since it seems fairly shallow but widespread, is this likely something that could be fixed simply with the Novus progression or will I need to start with a wet dry sandpaper?

Hmm, can't say to be honest. You'd have to drain it to try the Novus but you can use Micro-Mesh in a fully stocked tank, won't harm anything. If it's a mature tank, I'd be *very* hesitant to drain it just to do some sanding. I'd be more apt to try Micro-Mesh while still stocked - might take longer but I'd rather not disturb the balance.

Also is there a recommended RPM range for a variable speed sander for doing this?

I do a good bit of sanding with 2400 and keep it at the lowest possible setting. Too fast and you can burn the acrylic. Also, be very liberal with water if doing this on a drained tank. Even the lowest setting can burn the material if dry sanding.

The best kits I've found are available at micro-surface.com and they have hand kits and power sander kits. There is a 3m kit out there which I hear is very good, but I don't have any experience with it so really can't say how good it is or where to get it.

James

 

[NYDiesel]

I recently received a 125 gallon acrylic tank.Dimensions are 72"x24"x24" and 3/8" thick acrylic.The top has 2 narrow openings currently.If i decided to cut it down to 16" high what would be the best way to brace the top? Whats the highest i can go without bracing? looking to make a frag/display tank.Thanks in advance

 

[NYDiesel]

^^ Correction-72"Lx18"Wx24"H

 

[Acrylics]

I recently received a 125 gallon acrylic tank.Dimensions are 72"x18"x24" and 3/8" thick acrylic.The top has 2 narrow openings currently.If i decided to cut it down to 16" high what would be the best way to brace the top?

probably similar, just larger openings. Or 3 top openings with a coupla crossbraces, depends on your lighting scheme

Whats the highest i can go without bracing?

Not high at all, not high enough to make it worthwhile anyway. Maybe 6-8" and that's about it IMO

James

 

[NYDiesel]

Thanks Acrylics..Im going to cut the tank down to 16" and go from there. Maybe a 3" eurobrace?..I have access to a router and circ saw..what bit or blade is best?

 

[Acrylics]

yeah, 3" or a li'l better, but you will need the center-brace. I'd use a router with a flush trim bit.. Double face tape strips of *whatever* onto the top to use as router guides. I wouldn't plunge into it though with anything, just take any spade bit out and drill a pilot hole.

James

 

[Saltwaternooby]

Question I want to build a 160g out of 7/8" with these dimensions without bracing. Is it possible? Or what is the smallest bracing option?

Tank Height = 24"
Tank Width = 32"
Tank Length = 48 "
Approximate Gallons = 160

Got a sheet that is 10' by 4' that's 7/8 for cheep.

And could a local plastics shop cut it?

 

[Editour2]

I have 2 sheets of acrylic I picked up from Home Depot....I think they are 1/4" thick, (.220 I seem to recall), each sheet is 72" x 36". I would like to build a refugium with the following dimensions....46" long x 23" high x 12" front to back.
Questions: 1) Can I cut this acrylic using my table saw? 2) Can I just glue this together using weldon 16? 3) I am thinking that a brace will be needed all around....what and how do I do this? Can I just cut a piece of acrylic 2" wide and glue all around the top while also adding some type of center brace? If there is a link to walk me through this I would greatly appreciate it. Tried looking through this thread but it has been split so many times and is voluminous. I do have a 40 gal sump as a model (can't use it because it is too wide). Thanks in advance for any help.

 

[Acrylics]

I have 2 sheets of acrylic I picked up from Home Depot....I think they are 1/4" thick, (.220 I seem to recall), each sheet is 72" x 36". I would like to build a refugium with the following dimensions....46" long x 23" high x 12" front to back.
Questions: 1) Can I cut this acrylic using my table saw? 2) Can I just glue this together using weldon 16? 3) I am thinking that a brace will be needed all around....what and how do I do this? Can I just cut a piece of acrylic 2" wide and glue all around the top while also adding some type of center brace? If there is a link to walk me through this I would greatly appreciate it. Tried looking through this thread but it has been split so many times and is voluminous. I do have a 40 gal sump as a model (can't use it because it is too wide). Thanks in advance for any help.

IMO this material simply isn't thick enough to built the tank. Either lower the height substantially or get a thicker material

James

 

[Editour2]

IMO this material simply isn't thick enough to built the tank. Either lower the height substantially or get a thicker material

James

What is a height that would hold up using this material? If I reduce it from 23" height to 16" would that work? Actually with that reduction I could make a top that would be 1 piece with 2 cutouts (left and right).
Frank

 

[Acrylics]

What is a height that would hold up using this material? If I reduce it from 23" height to 16" would that work? Actually with that reduction I could make a top that would be 1 piece with 2 cutouts (left and right).
Frank

That would be very helpful. The problem is two-fold; 1) the material is very thin and the 46" span is pretty long for that height and that material - kinda pushing the limits of the material, and 2) the material is extruded material, which can't handle the stresses that a good quality cast can withstand. A 1 piece top with a good radius in the corners of the cutouts will certainly help.

James

 

[Editour2]

That would be very helpful. The problem is two-fold; 1) the material is very thin and the 46" span is pretty long for that height and that material - kinda pushing the limits of the material, and 2) the material is extruded material, which can't handle the stresses that a good quality cast can withstand. A 1 piece top with a good radius in the corners of the cutouts will certainly help.

James

James,
I thank you in advance for your help....I have never done this before..I am a bit confused by what you mean regarding "the material is extruded material". If it helps I checked with Home Depot and the product is manufactured by Optix. Also, I guess I will be using a router for the radius cuts...do you think the straight cuts can be made with my table saw? OR should I cut everything with the router? Can the straight edge that already exists be utilized or do I need to take off a bit (1/16") to provide a fresh edge for joining? I read about using pins when applying the weldon.....is this basically used as a spacer between the 2 pieces being joined? Lastly, (for now), I have some weldon 16...can this be used or should I use 4?
thanks again,
Frank

 

[Acrylics]

look through this thread for a little tutorial
http://reefcentral.com/forums/showthread.php?t=390652
many of these questions will be answered in there. Optix .220 material they sell at HD is extruded acrylic, a fairly low grade material which is fine for small display cases, replacing windows, etc., but not very good at handling the stresses of pressure vessels such as the tanks in this hobby.
IMO 16 is pretty much useless garbage. Anything it can do - something else can do far better

James

 

[Editour2]

Does that mean you don't like any Weldon products or that 4 is the preferable way to go?
I'll take a look at that thread.

 

[Acrylics]

I'm not particularly fond of the weld-on line, bit it is pretty good and the industry standard. Just that they are rather generic and made for lots of materials in lots of environmental conditions so they have to be rather generic.

James

 

[Chatouille]

look through this thread for a little tutorial
http://reefcentral.com/forums/showthread.php?t=390652
many of these questions will be answered in there.

Wow James... haven't seen that thread in a while. Brings back lots of memories of when you had to hold my hand thru my tank build. :wavehand: BTW, it's still holding water after 6 years of use, all due to your expert tutelage.

I've been away from the forums for a bit, but it's great to see how active you still are with helping everyone here.

Hope everything is well with you.

Chris

 

[CJBROWN]

Euro-bracing has been cut back

Euro-bracing has been cut back

Lots of great info here James, been through a bunch of the thread...

I am just finishing up plumbing and did a test run in the garage with this older tank. My question is about structural integrity after the previous owner cut back the bracing. I added the external box and full of water I notice there is a pretty good jog in the brace where the external box is glued on. The brace is only about 1" across the back. So the back is bowing out and the box is holding it in, so there is more bowing in the tank back at the ends of the tank. Do you think I have an issue here or will I get advance notice of impending disaster if what is left of the bracing starts to crack? I cut the drain slots in the tank back to flow to the overflow box.

 

[blackizzz]

James,

A couple weeks ago, you recommended me to "mix/blend/make" my own solvent.
Do you have a recepy of whats needed, or a link to it? I've tried to search and look for it, without luck.

Thanks

//Oskar

 

[Chatouille]

blackizz-

try these posts.....

http://www.reefcentral.com/forums/showthread.php?p=16080979&highlight=methylene+chloride#post16080979

http://www.reefcentral.com/forums/showthread.php?p=17838687&highlight=methylene+chloride#post17838687

They should be what you are looking for.

Chris

 

[blackizzz]

thanks!