Acrylic fabrication questions? I can help!

[Robert Patterso]

<a href=showthread.php?s=&postid=12179686#post12179686 target=_blank>Originally posted</a> by tundra1000
Awkward because of the base plate. Some one else might have a better thought but I would use a bandsaw with fine blade, make a tray so that the base hangs over and the tube sits nice and square then cut it off as close to the base as you can. Then you can run through a table saw jig to clean up the cut. Probably also be easiest to just put on a new base instead of trying to clean up existing

Is this the right skimmer?

Mine doesn't have a baseplate and is built a little different. Bandsaw, good idea. Should of thought of that. Now if I only had a band saw.
Thanks

 

[leebo_28]

Hey there,
Have you ever used the transition acrylic?...goes from black to white when lit , I am doing a job that calls for it , but I don't know if the glossy side goes out or the matte finish goes out , or does it matter?

 

[Acrylics]

Tundra1000,
too much to go into really, something I generally don't recommend here. There are many steps to doing it correctly from making absolutely certain the piece is truly squared, to heating temps and times, then must all be machined afterwards to get rid of the flares. In all but a couple of cases, the jigs set up in shops for doing this are essentially permanent set-ups so that nothing moves. 1/2" should be fine, 3/4" would be tough to do with a radius that small without messing the material up and would require a double sided heat strip so it's simultaneously heating from both sides.

Borge,
I'd use the 1" for the top and get another piece of 3/4" or 1" for the bottom.
IMO you will want a crossbrace on that tank, I'd use 4" perimeter flange w/ a 7" crossbrace yielding 2 top openings measuring ~ 24 x 19"
If the tank will not sit flat on the bottom because the bottom is warped, clamp as needed but if doesn't sit flat because the assembly (4 vertical panels) is not true, then you're in for issues IMO. If it doesn't sit flat now - it won't sit flat with a bottom glued on which will put more strain on the glue joints when filled with water.
Gluing the bottom is tough at times esp on large tanks w/ thick material. It is a kind of "speed gluing" without making mistakes. Simply takes practice. I start at one corner and don't stop until going all the way around while someone else pulls the wires behind me except for the first couple of wires - those must stay so the joint stays liquid.
Not sure where the term "eurobracing" came from but it refers to just a perimeter flange and no crossbracing. Standard bracing is the perimeter flange and any necessary crossbracing. Given the size of your tank and the material thickness you are using - I wouldn't even contemplate not using a crossbrace.

Robert,
Easy if you have a router table but if you can take all the parts off can be easily mounted in a large lathe or on a mill. Depending on the material, usually machines like aluminum or any other non-ferrous metal. If you have a router table, lemme know - there are easy ways with that.

Leebo_28,
Couldn't tell ya, never worked with that stuff before, sorry

HTH,
James

 

[tundra1000]

Thank you James, based on that I'll just go with square corners, just thought it would look nice to have the radius.

 

[Acrylics]

Glue it up and then use a router & roundover bit to machine the radius afterwards, that part is easy. The maximum radius you should use IMO is the thickness of the material so you don't cut into the joint at all. Eg, if using 1/2" material, the max radius is 1/2" and so on.

James

 

[Borge]

Borge,
I'd use the 1" for the top and get another piece of 3/4" or 1" for the bottom.
IMO you will want a crossbrace on that tank, I'd use 4" perimeter flange w/ a 7" crossbrace yielding 2 top openings measuring ~ 24 x 19"
If the tank will not sit flat on the bottom because the bottom is warped, clamp as needed but if doesn't sit flat because the assembly (4 vertical panels) is not true, then you're in for issues IMO. If it doesn't sit flat now - it won't sit flat with a bottom glued on which will put more strain on the glue joints when filled with water.
Gluing the bottom is tough at times esp on large tanks w/ thick material. It is a kind of "speed gluing" without making mistakes. Simply takes practice. I start at one corner and don't stop until going all the way around while someone else pulls the wires behind me except for the first couple of wires - those must stay so the joint stays liquid.
Not sure where the term "eurobracing" came from but it refers to just a perimeter flange and no crossbracing. Standard bracing is the perimeter flange and any necessary crossbracing. Given the size of your tank and the material thickness you are using - I wouldn't even contemplate not using a crossbrace.

Nice, I'll mill out the 1" plate then.
If I understand you correctly, a 4" all around and a cross in the middle with 7", right?

The bottom plate is warped alright, nah, the alightment on the verticals is pretty sound I think, ok some here and some there, but those I'll just grind off with a router or something.

As for the gluing; for now I just applied the glue to the "bottom" pieces, and placed the sides on. First the front, then lifted front w/sides and put it atop the backside. Used maskin tape as a barrier and gained a fillet on the inside from the excess glue.
I'm using a glue called tensol 70, works pretty good, mixing then waiting a few minutes to get rid of the air bubbles. Never tried the capilar method with anything other than metal pieces. You know that this is possible with every kind of glue?

 

[Acrylics]

Sounds like Tensol 70 is similar to Weld-on 40, a very thick, syrupy 2 part resin? Can you say what the ingredients are? Should be acrylic monomer (syrupy) and a catalyst if same as 40.

Capillary method can work with resins like 40, many shops will place a .090-.125" "shim" on each corner (later machined off) and fill the gap with 40 using syringe (no needle). It works but not bullet-proof.

Personally, I like capillary w/ solvent on the bottom. Primary reason is that it will yield a flat bottom provided the machining is straight. Filling a joint w/ 40 can yield uneven bottom as the "flatness" is dependent on the consistency of the gap. That said, can work and work very well

ETA: yep, 4" all around and 7" crossbrace, this does not account for overflow(s) though which must be accounted for

James

 

[Borge]

<a href=showthread.php?s=&postid=12188360#post12188360 target=_blank>Originally posted</a> by Acrylics
Sounds like Tensol 70 is similar to Weld-on 40, a very thick, syrupy 2 part resin? Can you say what the ingredients are? Should be acrylic monomer (syrupy) and a catalyst if same as 40.

Capillary method can work with resins like 40, many shops will place a .090-.125" "shim" on each corner (later machined off) and fill the gap with 40 using syringe (no needle). It works but not bullet-proof.

Personally, I like capillary w/ solvent on the bottom. Primary reason is that it will yield a flat bottom provided the machining is straight. Filling a joint w/ 40 can yield uneven bottom as the "flatness" is dependent on the consistency of the gap. That said, can work and work very well

ETA: yep, 4" all around and 7" crossbrace, this does not account for overflow(s) though which must be accounted for

James

Right then, I'll glue this one as the other sides,
*wet the glueing area
*lower the frame onto the top/bottom
*apply pressure to even out the warp. (not so much on the bottom as one of the side panels ;D)

done deal then ?

 

[Acrylics]

<a href=showthread.php?s=&postid=12188484#post12188484 target=_blank>Originally posted</a> by Borge
Right then, I'll glue this one as the other sides,
*wet the glueing area
*lower the frame onto the top/bottom
*apply pressure to even out the warp. (not so much on the bottom as one of the side panels ;D)

done deal then ?

As I have never built a tank in this manner, I can't qualify myself to say one way or another, hope you understand. If you are comfortable with it...

James

 

[Borge]

ok, how do you contradict the warp on the bottom/top then ?D

 

[Acrylics]

If gluing by capillary method, the weight of the vertical panes will counter the warpage in the material on the top & bottom.
Bewteen that and I try to keep material on the floor long enough to flatten out

James

 

[Borge]

<a href=showthread.php?s=&postid=12189827#post12189827 target=_blank>Originally posted</a> by Acrylics
If gluing by capillary method, the weight of the vertical panes will counter the warpage in the material on the top & bottom.
Bewteen that and I try to keep material on the floor long enough to flatten out

James

**** that sounds more like scifi, ever seen a 1" panel that small flatten out within a reasonable time? Say... overnight! =D

Tomorrow I would most definetly program one of my mills to you earlier posted hole size. How about those radius' got any special notes for me to take? r100? (that would be metric in mm)

heh, I bought a 6x80w T5 from ati, much of it actually gonna be over the acrylics.
I had a long look at the LumenarcIII Large MH's, those would probably be a better fit ;D, still I'll wait for some cool LED lights to appear at a reasonable price I recon.
Well,when I take a closer took at my T5's I see that they are only <1.50meter x 300mm So I'll only miss those 7" in the middle. Not to much I guess.

As for the earlier mentioned inlet/outlet, my original plan was to actually weld two pvc pipes throught the bottom. This we do from time to time at work on other gaskets and crates for water and gas. I've pondered this back and fort pros/cons. What is the likelyhood of gluing extruded acrylic tubes to the bottom instead (aestetics), with success?

 

[dzeadow]

Acrylics or other gurus:

I have a cube stand and am finding it difficult to utilize the space in the manner that I want. I just got back from a glass shop and got 2 9"x36"x1/4" and 4 12"x33"x1/4" panels for $10 total, pretty good deal I thought. Anyways, since none of the panels are big enough to do what I want, I was wondering if I could make 2 boxes, one like 12x24 and the other 12x12 and some how glue the two vertical panes together and then drill a hole through them... will this work some how? I'm basically trying to make an L shape but don't have a large enough bottom panel to do it out of one piece. TIA.

 

[detrazgw]

Want to verify design.

Want to verify design.

This thread is incredible! I have read allot of it and digested as much as I can. I want to build the tank I have pictured below and would like a sanity check that the parameter are within acceptable limits. This is going to be a species tank and a confidence builder for the display tank that will follow. I don’t know if the overflow design is a sound one either so if someone sees or knows inherent problems with this please let me know.

TIA
George

 

[RokleM]

dzeadow, I've seen a number of setups where multiple smaller sumps/fuges are tied together via bulkheads or uniseals. You could do something similar with your space. Just ensure you leave enough room when you build it for the plumbing in between.

As for your back wall, I can't comment on the complexity of bending the back acrylic, matching the sides up with the corner to get a perfect flat bond at an odd angle, etc... but I imagine it's not easy It's a cool idea, but you might be better served to just do a standard flat, black, full back section instead. It wouldn't take up that much more room. Also watch the size of your brace via back area. It looks like you'll have very little room to work back there, let alone replace/install PVC etc if necessary.

 

[detrazgw]

I am not sure I will be able to get a piece to bend like that either. The way I hope to manage this is to create a form from a rolled piece of sheet metal. Then place the acrylic sheet on the inside or outside (not sure if it maters) and use a heat gun to soften the piece till it sags to the shape of the form. Also not sure if I need to remove the protective masking before heating. As far as bonding to the tank my thoughts are to see if I can create a close fit and not bond it. My hope is that between the lower water level and live rock against it that it would remain in place. This would allow me to install plumbing prior to placing back wall. Am I coo coo or does this sound possible? Don't answer the coo coo part, I probably am, just the possible part!

TIA
George

 

[Borge]

<a href=showthread.php?s=&postid=12203285#post12203285 target=_blank>Originally posted</a> by detrazgw
I am not sure I will be able to get a piece to bend like that either. The way I hope to manage this is to create a form from a rolled piece of sheet metal. Then place the acrylic sheet on the inside or outside (not sure if it maters) and use a heat gun to soften the piece till it sags to the shape of the form. Also not sure if I need to remove the protective masking before heating. As far as bonding to the tank my thoughts are to see if I can create a close fit and not bond it. My hope is that between the lower water level and live rock against it that it would remain in place. This would allow me to install plumbing prior to placing back wall. Am I coo coo or does this sound possible? Don't answer the coo coo part, I probably am, just the possible part!

TIA
George

Don't use a heat gun. Put some CLEAN new blanket on the form, put it in a oven.
We have some ovens here at work where we dry out different types of plastic composits, where do also do windscreens in pmma and pc. Works fine.
DONT TOUCH the heated plastic with fingers. It will... not as much craze as it will get grey.

 

[Acrylics]

If you don't bond it - it won't act as a true overflow. If you are not concerned about that, just use a thinner piece of material and just bend it by hand and stick it place - no heat forming necessary. In either case, it's just a decorative false wall. For this, no problem and is easily done but remember that the standpipes in back will actually be the overflow, not the wall.
OTOH if you actually wanted it to work like an overflow, it must be bonded and must be able to support the load of water one side if the other is empty.
Also remember to make it big enough to access the parts inside, to adjust, modify, remove and replace them as necessary. From just looking at it, you're at roughly 2.5 - 3" of access (front to back) which simply isn't enough IMO. I don't like the idea of not being able to make changes down the road without taking the tank down.

IME the heat gun will not give even heat to make the part consistently curved. If you plan to heat form it in any way, take the masking off.

HTH,
James

 

[detrazgw]

Yep... I was thinking about that. I am hoping I can fit it well enough that the seepage will be well below the total volume of water cycling through the tank. Assuming I can achieve a tight fit or bond it I was planning on using 1/8 inch wall thinking also that the curve against the water pressure with the ends pined against the sides it could handle the pressure. Is this practical being that the water level would only have a couple of inches difference the majority of the time? I am sure the amount of room need for access is subjective but is there a number I should shoot for? I don't have any experience with an overflow.

TIA
George

 

[Sango-chu]

AcrylicMan, I apologize up front for not being able to nor attempting to read thru 6 years of thread. But I do refer to bits and pieces often Your advice is great. Hence, my question. I just puchased a 3 meter long tank that was being used to hold stock corals. It's sea-worthy, not leaks, but I would like to "clean it up a Bit" I need a recommendation as to which kit to use in order to save time, the acrylic itseld, and just some of my sanity. I was just about to purchase the heavey damage removal kit to fix up and polish the tank

Or should I just go with a light damage kit? Or anything else you recommend please...

Looking forward to your great assistance!!!!