DIY Tank (Dialup beware), Step by Step

[woz9683]

I thought of something else. I remember reading somewhere that it was important which way your applicator needle was pointed while you are applying the solvent, but I can't remember which direction or why it would be important. Is it, needle pointed back toward the start of your glue joint (applicator bottle leads solvent) or needle pointed toward the end of the joint (applicator bottle follows solvent)? The first seems like the most likely just for the ease of use, but maybe not. Or maybe the point being made was entirely different. Does this sound like something you've heard about before, maybe I mixed it up a little?

 

[H20ENG]

You dont want to push the needle into the melted acrylic. It will clog the needle. Always drag it

 

[woz9683]

That's what I figured. Thanks

 

[Acrylics]

Funny, this is one thing that I do the exact opposite of the rest of the industry. I push mine forward, keeeping the solvent flow a coupla inches ahead of the needle. I just find it easier to control. Clogging is limited if you keep constant pressure on the bottle, if the solvent is constantly coming out - hard for ooze to get in. May also help to use larger applicator needles, I use 18ga so a little bigger than most. Before and after each joint, blow a little out when you create your vacuum to clear any clogs.

James

 

[woz9683]

Ok, I thought I'd heard you say something about this before James. It does seem like it might be easier to keep plenty of solvent in the joint this way. By "create your vacuum" you just mean blowing the air out of the bottle before you store it, correct?

 

[Acrylics]

<a href=showthread.php?s=&postid=9416006#post9416006 target=_blank>Originally posted</a> by woz9683
By "create your vacuum" you just mean blowing the air out of the bottle before you store it, correct?

..before you *start*

James

 

[H20ENG]

I was thinking about this, and I guess I actually hold the needle at 90 to 120 degrees to the joint. I'll try it James.

 

[woz9683]

Hey James,

I've got all my material cut to size for my tank, and I did some modifications so the design isn't a true coast-to-coast overflow but should still be a much better skimmer than one with teeth. I just wanted to see what you think about the bracing design before I start cutting holes out of the top piece. I didn't label all the dimensions and the ones I did label aren't perfect anyway. So, here goes: Tank is 48"L X 30"W X 20"H. Overflow box is 48"L X 6"W X 6"H. The top is a single piece 48"L X 36"W to cover the overflow box and tank. All corners on holes will be 2" radius. The perimeter flange is 3"W. The crossbraces are all 4"W. The places between the sections of the overflow that contact the top piece are 4"L also, but these should be irrelevant. The overflow itself is 1/2" deep. So, what do you think? Is there enough bracing? Could I just make it a true coast-to-coast? Oh yeah, all material is 1/2" Acrylite GP, except the back wall which is black Plexiglas G, also 1/2".

 

[woz9683]

 

[woz9683]

Wow, adding pictures on here can be a pain sometimes. Here's the last one. Please let me know what you think.

 

[woz9683]

Well, I'm bored. Here's one more, just to make sure the dimensions of the flange and cross-braces were understandable. Again, 3" perimeter, 4" across the middle.

 

[melev]

I love your pictures, but would suggest that your overflow may be a bit too high in the tank. Remember that water will flow over the baffle itself, as much as 1/2" higher. Do you want 1" of air between the surface of water and the acrylic top?

 

[woz9683]

The reason I made it only 1/2" was an attempt to keep snails and such from getting into the overflow. If I made the slot 1" most of my cleaning crew would be able to get back into the overflow area. With a couple dursos back there they would still have a hard time getting into the actual pipes, but I would like to avoid the risk. When I first started looking into the coast-to-coast option I remember hearing about 1/8" sheet of water going over the overflow? I guess I need to calculate some flow rates and actually see what kind of volume of water I can move over mine. Any idea of a calculation I can use for this?

Do you want 1" of air between the surface of water and the acrylic top?

Do I need it?

 

[melev]

I like a little space at the top of the tank. If you stick your arm in while it is running, will it make the water rise up inside those openings in the top? :eek2:

It comes down to how you want the tank to operate. I can't help on the math question. Sorry.

 

[woz9683]

I like a little space at the top of the tank. If you stick your arm in while it is running, will it make the water rise up inside those openings in the top?

Yeah, that might not be pretty.

I found a website with a little flow rate calculator. http://www.flowcalculator.com/
I changed it to a rectangular channel with a total of 26"W (mine should be a little wider than that), .25"D (only use 1/2 of my 1/2" overflow), and 1.5 ft/s velocity (this is what I'm not sure about, 1.5 was just the default). This gives me 1,800gph flowrate. Seems feasible if the velocity is correct. The tank has a fairly large surface area compared to most(your tank excluded, of course ) so the water my arm/arms/head displace shouldn't raise the water level too much. What do you think?

 

[Acrylics]

Hiya Michael,
Personally, I'd recommend a coupla changes:
Remove one of the crossbraces and just use one 6" wide brace, along with the 3" flange - it'll be fine.
Change from 3 overflow slots to 2 wider slots. This will allow for the corssbrace to make contact with the back of the tank and the back of the overflow in the center.
If you follow the above; you'll end up with 2 larger openings over the overflow, make 'em like 4" wide as well rather than the 3.125". At 4" x 18", you'll have more access to the oveflow.
Personally, I'd make the overflow slots more like 3/4" deep (for various reasons but splashing is the majority reasoning). You could add eggcrate in there to keep more critters out if'n ya wanted to.
I'd also make the overflow itself taller, maybe 10" or so. A 1.5" Durso requires a little height and they have to be completely under the overflow covers to keep noise down. You are making overflow covers aren't ya? hint hint

Everything else is dandy...

HTH,
James

 

[woz9683]

So, like this?

 

[Acrylics]

IMO, Perfect

James

 

[woz9683]

Is that ok with just a 4" brace between the overflow slots and main holes? I already had the pieces cut for the overflow, but I've got plenty of black material left over. I could cut a 10" strip out of it to make the overflow taller, and then use the 6" clear piece for overflow covers?

 

[woz9683]

Oh, and one more thing , yeah right. To rough cut the openings in the top what do you use? I was thinking I could get away with a clean cutting jigsaw blade. It's supposed to be for laminate and stuff like that. The teeth don't have any rake so maybe they won't chip the acrylic?