DIY Tank (Dialup beware), Step by Step

[woz9683]

Yes, they're only charging you for what you take, but they're pricing it at a per square foot price. Generally, it's cheaper to buy material by the sheet. You should be able to get two full sheets of 1/2" for around that price. Are they cutting the pieces to exact size or would you still be doing the final pre-glue router work? If you're doing the final routing, I think the price would be very similar if not cheaper for you to go ahead and get two full sheets. Obviously, the purpose of purchasing the full sheets would be getting the extra material to add a full top to your design to make it stronger.

I'm not sure what material Port plastics sells, just make sure whatever you get is Polycast, Acrylite GP, or Plexiglas G. And other than suggesting to definitely stay local, I don't have any other specific places to suggest.

Colored material is harder to work with because when the solid colored piece is on top while you're gluing you can't see if you're getting a nice even fill of solvent. It's also more expensive, especially wen buying small quantities.

You'd have to cut your tank size down significantly if you wanted to get the whole thing out of a single piece of material, which would be the only easy way to drastically reduce the cost ($200 or so per sheet, by the way). I was thinking 30x30x18 or 28x28x20 (either would have enough material left over for the overflow), but that's really a big drop. Probably too much for you to consider.

 

[woz9683]

I wrote that earlier before your last post, but got a busy server and couldn't post until now. In addition, you really should avoid any brands aside from those 3 that I specified. Considering that's a per square foot price it's actually pretty cheap, which means the material is probably cheap. I don't know if you can do the edges yourself, but I'd say get two sheets of quality material and do all the cutting yourself.

I think, if you find a place using quality material, the cost for all the cuts premade is going to jump up significantly.

 

[miwoodar]

So how does this sound? I have a quote for 2 sheets of clear Plexi G for $460. They will cut it close to the approximate size then I will take it to the second shop to have the final trimming and routing done for $20 by a guy who has experience building tanks. I'll end up with a 38x38x29 in 1/2" with a one piece top. How big should the eurobracing be for this? Would you up it to 4"? Would that include the thickness of the acrlyic (actually cut it to 4 1/2")?

If I practice on a handful of scraps I will be able to pull this off, right? I'm fairly handy, have attention to detail, and have read a number of these threads in their entirity.

Here's a summary of my notes:
* For 1/2", use actual push pins (I'm not worried about oozing as much as I am about bubbles and I want very strong seams)
* Push the pins in half the thickness of the acrylic sheet
* Use #4 and overcut the acrylic in the appropriate places to give me a spot to apply the glue
* Make sure the bottle stays behind the flow rather than leading
* Add shims directly under the pins until all of the pins are slightly snug
* Apply more #4 as I am pulling the pins
* In Denver, at 75 degrees in my basement and ~40% humidity, I should wait about 30 seconds before pulling the pins
* Pull the pins out in order from where I began with the glue
* Use a 20 gauge needle to apply the glue
* Use a fresh spiral upcut bit to trim, make sure the bit stays clean of debree (Whiteside, MLCS Katana, Bosch, or Dewalt)
* Work on a flat, steady surface with some type of foam board
* If I see a wet spot as I'm pulling a pin, add a shim to that spot
* Order of operations...route the overflow, glue the front pane to one of the sides, then the other side, then the back, then the top, route the top, add the overflow box, then add the bottom

Anything I missed?

 

[miwoodar]

<a href=showthread.php?s=&postid=11615423#post11615423 target=_blank>Originally posted</a> by woz9683
I don't know if you can do the edges yourself, but I'd say get two sheets of quality material and do all the cutting yourself.

I wish. My table saw is a POS and I will be using a borrowed router. I would love to upgrade my saw and buy a router but it would come down to new tools versus getting a new tank. Plus, I don't want to ruin any of the edges while I am learning how to use the tools.

 

[miwoodar]

Other notes I forgot about...

* Don't weight down the piece, let the weight of the acrlyic do the work
* Use plastic speedsquares with the corners knocked off and apply them with double sided masking tape

Lastly - something I didn't read but I expect to be true - it's not a bad thing to wait a touch longer than 30 seconds (up to 60 or 90) to let the #4 start to goop up. This would be preferred to pulling the pins too early and possibly ending up with a dry joint.

 

[Chatouille]

miwoodar-
I didn't care for the speed squares... I made a right angle jigs out of MDF for my projects. It made clamping the acrylic easier for *me*.

* Add shims directly under the pins until all of the pins are slightly snug

When adding shims... you want to make sure that there is equal tension on all of the pins. After you have it shimmed, pull your pins and examine the entire joint to be sure that the pieces mate together properly. It's easier to do a dry run and check things, then to try and correct it after the weldon has been applied.

About the only other thing I would suggest is to play with a few scrap pieces beforehand to see what works best for *you*.

-Chris

 

[miwoodar]

The problem with the MDF jigs in my head is I have no way of knowing if they were exactly 90 degrees until I am to the point of applying the bottom. How did you ensure that yours were perfectly square? The math of the sides?

If you hadn't ever built an acrylic tank, would you throw $500 at a project like this with the expectation of success? I'm getting nervous thinking about what my wife would say if I told her I messed it up...

 

[Chatouille]

When I made my jig's, I used right angle clamps, and then checked them afterwards with a square.

If you hadn't ever built an acrylic tank, would you throw $500 at a project like this

I did , my tank build is documented in this thread. It's also why I suggest to get a few pieces of scrap to play with first. Atleast you will get a feel for what you are doing before you start on the real thing.

It all comes down to what you feel comfortable with, and what works for *you*. Like I didn't care for the applicator bottle, and went with a 2 oz syringe with 18 gauge needle. For me, it was easier to control.

-Chris

 

[Acrylics]

The MDF jigs are only used for gluing the vertical panels together. You'll know if they are out of square when you do the first glue joint using them as the "gluing" end of the vertical piece will not sit flat.

I'd highly recommend you practice a bit prior to tackling this. You'll not only get the practice but also get a "feel" for it - if it's not for you, better to know that now than after you cut up a bunch of material.

And NO NO NO to the "import" material, it's absolute trash for this application. Port carries Polycast, not sure how much stock that branch will have but they absolutely carry Polycast as well as Cyro GP. Plex G will be fine, far superior to the import.

For the eurobrace, definitely use a 1 piece top with 1" radius minimum, will help distribute the load much better. At 29" high with that footprint, might be kinda pushing it for 1/2" for deflection. It can easily hold from a structural perspective but will tend to bow over time a little more than one would like to see.

You've been given good advice by Michael and Chris IMO and very worthy of following :thumbsup:

HTH,
James

 

[woz9683]

James, how wide would you suggest on that eurobrace?

 

[H20ENG]

An easy way to shim is to start with NO pins, just set the side piece on top of the base piece.

You will be able to see light under the side piece if there is a gap. This also makes it easy to see any glaring defects, like a divot from the router, etc.

You can even use a $3 automotive feeler gauge to "search" for gaps that you cant really see. Just use the .003 or so and drag it along the joint. It'll catch or slip underneath if there is a gap.

Now shim it to lose any gap. Then put your pins in and it will be perfect. Your pins MUST be all the same thickness for this method, so dont just use random stuff laying around.

I use copper wire since I have oodles of it, but James recommended wire ties that come with plastic trash bags, just strip the paper off. They work great too.

I would NOT use push pins. Too big, and you run the risk of getting glue under your jig. Ask me how I know

I second losing the plastic squares. Its not that hard to square up a jig. Just be sure to lop the corner off on the tablesaw. Look at the jigs James uses. Very easy to make and the spring clamps help a lot.

See if you can get some scrap to practice on. It will give you way more confidence on the bigger project.

That 30 seconds will go FAST, so you may want a helper on the main tank seams.

Best of luck, glad you are doing your homework.

Acrylic fabrication is alot like golf. Lots of stuff to remember to do all at once, and sometimes you slice

 

[woz9683]

I wish. My table saw is a POS and I will be using a borrowed router.

I actually do the rough cut with just a circular saw and a good blade.

If you hadn't ever built an acrylic tank, would you throw $500 at a project like this with the expectation of success? I'm getting nervous thinking about what my wife would say if I told her I messed it up...

Definitely, you're list of details looks pretty darn good. Practice a little with some scrap just to get a feel for the flow of the solvent and to get a better idea of the time before pulling the pins. I think 30 seconds might be a little quick for WO#4.

 

[Chatouille]

That 30 seconds will go FAST, so you may want a helper on the main tank seams

Yeah... those top & bottom joints are long. When I did mine, I used small guides double taped down on each side. That way when the pins are pulled, the thing won't shift on you. There is an example of these on page 4 of this thread that James posted.

James, good to see you... I've been away from the boards for awhile.

-Chris

 

[miwoodar]

<a href=showthread.php?s=&postid=11616458#post11616458 target=_blank>Originally posted</a> by Acrylics


For the eurobrace, definitely use a 1 piece top with 1" radius minimum, will help distribute the load much better. At 29" high with that footprint, might be kinda pushing it for 1/2" for deflection. It can easily hold from a structural perspective but will tend to bow over time a little more than one would like to see.

You guys rock! I think I'm going to do this...pending that I can convince my wife that it's OK that I've totally blown my initial budget.

OK, so I'll make a couple of good square jigs and practice a number of times before doing the real thing.

I'll use the twist ties minus the wrappers. Do you have any problems with keeping them nice and straight? I assume that half way through the width of the material is correct even with the thinner pins (wires).

Can you give me an idea of how much bow to expect? Will it be noticeable from across the room or will it be little enough that only I notice it? What if I cut an inch or two off of the total height - will that make a tangible difference?

I'm still planning the rim to be 3 1/2" with the final 1/2" to be overlapped with the panes. Enough?

No to the import material - glad I didn't pull the trigger without asking you folks first!

 

[Chatouille]

<a href=showthread.php?s=&postid=3321523#post3321523 target=_blank>Originally posted</a> by Acrylics
Yes, I use a block on each side of the baffle. Do note that this is on the second side and I use the blocks just to line the pieces up. I don't use pins but rather wires which will serve the same purpose, just that pins allow too much solvent in for my taste.

Here's the post from James I was talking about....

-Chris

 

[woz9683]

I'll use the twist ties minus the wrappers. Do you have any problems with keeping them nice and straight? I assume that half way through the width of the material is correct even with the thinner pins (wires).

On the pins I would tie a loop in one end of the wire or have some pliers ready to help pull them out. They can get tough to pull very fast some times. And yes, half way through the material thickness is fine. Not sure what you mean by straight, but the weight of the acrylic will flatten them out or if means slightly sideways, it doesn't matter.

James, will probably be able to give you the best idea on the amount of bow to expect. 29" is tall for 1/2" material, so there will definitely be some deflection.

I'm still planning the rim to be 3 1/2" with the final 1/2" to be overlapped with the panes. Enough?

My first thought here is definitely not thick enough, although I want to defer to James on this one. You're talking about a very tall 1/2" thick tank that's 37" long and wide with no crossbracing. I think the eurobrace will need to be significantly thicker than 3.5"

 

[Chatouille]

I used a 3-1/2" eurobrace on mine.... 37"x24"x20" made out of 3/8" acrylic, and I have a very slight deflection, ~1/8". I built this tank Dec '04, and it's holding up very well. If I had to do it over again.... I would go with 1/2" material like you are doing instead.

It was a great project, I really learned a lot, and enjoyed doing it. I'm sure I'll be building another one before too long.

-Chris

 

[Acrylics]

I'd *probably* use 4.5-5" (total) for the eurobrace but don't quote me on that, just sounds about right.

The amount of delfection you can expect will be noticeable from the ends but not enough to be distortive, my off-hand guess is 1/4", maybe a touch more, but given the span is only 37" - I wouldn't expect much more. Cutting down the height will help a bit, even a coupla inches will help. If you can live with maybe 25" height, your yield would be much better if you're using 4x8' sheets as you'd be able to get all 4 vertical panels from a single sheet.

FWIW, this would be a tank I'd build from 3/4" with 3" eurobrace, based mainly on height and most folks don't really like the wide eurobrace.

If you are using the MDF strips with camper foam (as shown on first page of this thread), you'll be able to gently push down on the horizontal piece to pull out the wires fairly easily. Wish I could easily explain this as it sounds like you'll kill the joint but it does work.

For shimming, there are 2 times to shim once you'r practiced. You can "pre-shim" to get all the parts fitting well prior to gluing. You can also shim after you apply the solvent if you're quick about it. These seconday shims would go between the camper foam and the acrylic, I use .030" and .060" Lexan for this but anything thin is workable. After you glue the joint, gently lift up on the lower piece, if you see the solvent move - needs a shim. Again - hard to explain but practice helps.

Chatouille,
Good to see you too my friend, I haven't been around much either lately but working on it

HTH,
James

 

[miwoodar]

<a href=showthread.php?s=&postid=11616898#post11616898 target=_blank>Originally posted</a> by woz9683
Not sure what you mean by straight, but the weight of the acrylic will flatten them out or if means slightly sideways, it doesn't matter.

I think I was making it harder than it needed to be.

Maybe I'll take an inch or two off the top and bring it down to 28 or even 27. 1/4 inch of deflection doesn't sound too bad to me though. I was hoping to end up with not having to stoop to see the water surface. The stand can't be increased in height due to the width of the doors in my house.

---edit---

5 inches leaves a 28 inch opening...I'll have to ponder on that. I can see what you mean about people wanting a smaller brace.

 

[woz9683]

Make the stand in two pieces, that's what I did. 36"x48" is the tank footprint, and the stand is 42" tall. The top and front make a single L-shaped piece and the back and bottom make another. Bolt together with a couple stainless steel bolts and you're good to go. Oh, and you'll probably want a vertical support in the middle on at least the sides. Just permanently attach those to one half and it will still be narrow enough to fit through almost any doorway.