Acrylic fabrication questions? I can help!

[Floyd R Turbo]

From James:

eurobracing.. start with 3" eurobrace on any tank..

24" high, use 1/2" minimum
30" high, use 3/4" minimum
36" high, use 1" minimum

with these in mind, I recommend a 6" wide crossbrace every 24" of tank length. So a 48 x 24" will have 3" eurobrace and a 6" crossbrace. If the same tank were 72" long - just one more crossbrace. At 8' length, I recommend jumping up one material thickness to keep deflection down.

There are times when someone's lighting scheme doesn't match the above formula. Ie., if someone wants an 8' tank but only 3 cutouts in the top. In such cases, I recommend increasing the eurobrace width to 4.5" and increasing the width of the crossbraces to 8".

Iv'e been using this formula, 1.5" radius corners, and material thickness minimums above, for many years and I have *never* had a tank fail.

If someone doesn't want the crossbrace - they simply have to make the material thicker, and/or increase the width of eurobrace to maintain rigidity.

For a 16x16 you could probably get away with a 2" euro

 

[Floyd R Turbo]

Here's the next one of the batch. This one is 60" long, and my table has deteriorated over time so it's not very level anymore. So I have to shim with big shims under the foam boards in addition to shimming under each pin. One of these days I'll rebuild the table - summer project

I ran that 60" long joint using a 2oz bottle and the #16 needle. Filled the whole joint in about 15 seconds. Did the clear/external box with that too, took about 8 seconds

 

[silentscream]

Man, I need to go and get a bigger needle. The #24 is so slow, it's tough to get everything done in time.

Floyd, how many acrylic projects do you typically work on in a week?

 

[Floyd R Turbo]

Do you mean the #22 needle? I don't think there is a 24. 25 & 27, yes, but no 24 (at least not from craftics)

The #20 needle runs a bit faster than the #22, it's a flex needle. So it tends to push the solvent backwards along the joint you are filling, the rigid needles are better and pushing the solvent straight into the joint, which allows it to get a forward bead going. The #20 flex needles are good but you have to get used to them. I stiffen them up by wrapping the needle with a couple passes of blue tape, leaving only the last 1/4" or so exposed

 

[silentscream]

I just checked, it's actually a 25 not a 24.

 

[Floyd R Turbo]

Yeah that one is pretty much useless for anything over 1/8" or maybe 3/16" thick. #22 works pretty good for just about everything except the long joints

 

[thejuggernaut]

How in the world do you route the end piece on the internal box without loosing a finger?!

 

[Floyd R Turbo]

Acrylic fabrication questions? I can help!

I'm not sure I understand what you are talking about. I have a router mounted in the table and use a spiral up cut flush trim bit. I just slide the piece on the table across the bit

 

[thejuggernaut]

The way I understand it is that the end pieces are machined to size on all four sides. But they are tiny. Do you cut them with a table saw and then prep or cut to size with the router?

 

[Floyd R Turbo]

I had these made on a CNC but I've made piece this small and even smaller manually without any issues, you just have to be careful. I have a 1" thick x 2" wide slab of black acrylic that I use for my fence, I clamp that down at each end and then pass the piece between it and the router bit using a 3/4" diameter double flute straight cutter (Bosch). As long as you are shaving off a small amount with each pass, the router bit tends to push the material away from the bit and into the fence. So I start with my right hand on the trailing edge corner of the part pushing into the fence and forward, and then when enough of it gets past the bit I put my left hand on that about 1" behind the bit then press my fingers on the table to hold it against the fence while I slide it past the bit, then move my right hand to the back of the piece and push it through while keeping my right hand on the part. If the piece is really thin, then I pull it through with my left hand. Sometimes I'll use a pusher in my right hand on the back edge. I've done this to make strips as thin as 1/2", routed on both sides. That is a little hairy.

The only time I've ever injured myself was when I was trying to make some blocks for fitting in the corner of a sump that I was repairing. I needed to gusset with triangle material and at each corner I needed a 1" or so cube. So I laminated a bunch of pieces together and then routed 2 edges, cut them into cubes and then tried to route the rough-cut sides. I didn't have a problem with the first few, just held on to them well. Then one got away from me and got pulled into the bit, along with my finger. That sucked and that is an understatement.

It could have been worse. Thankfully I was wearing a full mask 'cause I got splattered with acrylic bits. I decided to let the rest go as is since I was using WO40 anyways.

 

[thejuggernaut]

Dang. You're more of a man than me. No way I could get an inch from one of those high spinning bits! Were you afraid to look down to see if your finger was still there?

 

[Floyd R Turbo]

I didn't even feel it at first. It only shaved off about 1/8" of so off.

A side note, on making end pieces, what I do is make one piece that is 2x the width plus a bit more, make that square, then cut it down the middle on a table saw and route the rough-cut edges with the same fence settings (pass each piece through, adjust fence, repeat). This usually makes identical pieces, with a little practice.

The other method is to make one end piece then double-stick-tape it to another rough cut piece and flush trim it.

 

[rfgonzo]

Here's the next one of the batch. This one is 60" long, and my table has deteriorated over time so it's not very level anymore. So I have to shim with big shims under the foam boards in addition to shimming under each pin. One of these days I'll rebuild the table - summer project

I ran that 60" long joint using a 2oz bottle and the #16 needle. Filled the whole joint in about 15 seconds. Did the clear/external box with that too, took about 8 seconds

You said it took about 15 seconds for the 60" run, I only see shims on the one side, did you just do one side at a time? or go around the whole Overflow box at once? So 30 seconds to complete the entire box?

 

[Floyd R Turbo]

The last 2 pics are of each side. You can't do just half a joint, you have to do the whole joint in one shot - so 15 seconds to fill the entire joint all the way around (10+ feet) using the #16 needle.

 

[rfgonzo]

I know you can't just do half, thats why I was confuse. WOW 15 seconds all the way around!!!! I need to get me a size 16 needle.

 

[WmTasker]

I purchased two InTank media baskets from someone at a great price. They are an older version of what they have on their website and is larger than the new ones. Its about 1/8" to big to fit in my JBJ 45 Rimless aquarium. So I took my 200 tooth saw blade and cut the back wall off on my table saw. Worked great. It was just enough that it is now a perfect fit. I was going to secure it back on with just aquarium silicone. Is there something that would be more permanent that I can purchase at one of my localhard ware stores? I have a Lowes, Menards, and Home Depot.

Thanks, Billy.

 

[Floyd R Turbo]

For something like that which doesn't have to be water-tight, and stay together under pressure, you can use just about anything that is aquarium safe. Silicone would work but it might fall apart eventually. Epoxy would be fine. I'm not sure if cyanoacrylite (superglue) would work, but it might. IME superglue & plastics = goo. If you can fine WO #16 or Craftics #33, that would work. You might also try PVC pipe cement. Or if you happen to have any chloroform sitting around, that works too.

If you're gong to try any of these alternative methods I would get a few scraps and try it on them first

 

[WmTasker]

Thanks Floyd. I thought about the Weldon 16 but I don't know anyplace local that sells it. I thought about a 2 part epoxy but thought it might be hard to apply. I didn't think pic pipe glue would be to easy to out on. I guess I could use a 20ml syringe to apply it.

 

[Floyd R Turbo]

2 part epoxy should not be that hard, mix it up and use a toothpick to apply it a little at a time. You could also use a small paint brush (like ones that kids use for watercolor, etc)

 

[WmTasker]

Is there a certain brand that is better than others for reefs?