Acrylic fabrication questions? I can help!

[MrBlackIS300]

Thanks for the reply.

Well I was thinking 60" x 48" with 6" bracing and max height was meant before it fails. I'd like it to be min 24" high but if I could go a little higher it would be very nice.

 

[sick_bubblegum]

when the edges are prepped right, the joint vanishes when the solvent is applied and dries. so then you are just left with cleaning up the overhang and then polishing after all assembly is done.

ok, thanks for clarifying this. my local plastics shop is doing the cutting for me. they said the edges would be ok to glue as-is. hopefully this will be the case!

 

[Floyd R Turbo]

Their definition of "ok to glue" is probably very different than ours, if they are not used to building aquariums. You can glue an edge that is cut by a panel saw if you are making a display case or something of that nature. The edge can be done be free of bubbles and from the outset would look to be "perfect" but it would not be good enough for a pressure vessel over time. I would inspect the edges carefully and check for squareness of your end pieces.

 

[dahenley]

ok, thanks for clarifying this. my local plastics shop is doing the cutting for me. they said the edges would be ok to glue as-is. hopefully this will be the case!

floyd has some good inside.

while your at the acrylic shop. have them cut you some 3" wide strips a foot or two long. (a few of them out of scrap.) and see what pieces they have lying around.

then you can go home and practice gluing the pieces. (no order or anything, its all just practice)

then you can see how the joints look and try working with the solvent. (and see how it flows into joints.)
thats my best information.... practice. some acrylic places have bins of scrap that you can buy cheap. (that way you can play with different edges and not work and ruin the good stuff)

 

[sick_bubblegum]

thanks for all the great advise. take it slow and practice.

still wondering about this....

so, if i were making a 1 piece overflow box, would it be safe(r) to use a heat gun vs a propane torch? or does it even matter with an overflow box?

 

[Acrylics]

still wondering about this....

so, if i were making a 1 piece overflow box, would it be safe(r) to use a heat gun vs a propane torch? or does it even matter with an overflow box?

it's like asking what is safer; a gun or poison? heat gun = ~1000F, torch = even hotter.. both are far too hot, point source is too small and will probably fry your plastic.
neither are good at all.. while some have bent plastic with both, the results are usually shoddy at best and simply not good practice.. use a proper strip heater if you want to heat bend acrylic..

James

 

[sick_bubblegum]

thanks james! brings up another thought of mine....

how about bending a single piece of acrylic with a strip heater, to form the front and sides of a tank? i'm looking at final dimensions of 36" x 18" x 12". obviously i would need to make the bends in the right place, maintain 90 degree angles and make sure it stays flat. could this be a one-man job?

imo, this seems like an easier method compared to gluing all 3 pieces together individually. it would look better too.

 

[Acrylics]

thanks james! brings up another thought of mine....

how about bending a single piece of acrylic with a strip heater, to form the front and sides of a tank? i'm looking at final dimensions of 36" x 18" x 12". obviously i would need to make the bends in the right place, maintain 90 degree angles and make sure it stays flat. could this be a one-man job?

imo, this seems like an easier method compared to gluing all 3 pieces together individually. it would look better too.

aesthetics are subjective but it's not as easy as you might think. Can it be done? yup.. but after the piece is bent, both the top and bottom of it need to be routed again. There will be a flare created when you bend the piece and the bent corners will not sit flat - so it must be routed to get it to glue correctly.

I know you might not believe it, but gluing it is easier..

James

 

[overflowin]

i've got a couple questions about "recycling" some acrylic. i will most likely be purchasing an incorrectly built acrylic tank, and i'm planning on cutting it down and building a smaller tank with the bulk of the salvageable material.

my first question, what is the best way to protect the acrylic from scratches while i'm working with it? i was thinking masking tape and paper, but i have my doubts about that being the 'best' method.

my second question is about dismantling this thing... its a fairly large tank, and the idea of running it thru the table saw doesn't seem all that safe. straight edge and router?

any input would be appreciated...
thanks
donnie

 

[peppie]

i've got a couple questions about "recycling" some acrylic. i will most likely be purchasing an incorrectly built acrylic tank, and i'm planning on cutting it down and building a smaller tank with the bulk of the salvageable material.

my first question, what is the best way to protect the acrylic from scratches while i'm working with it? i was thinking masking tape and paper, but i have my doubts about that being the 'best' method.

my second question is about dismantling this thing... its a fairly large tank, and the idea of running it thru the table saw doesn't seem all that safe. straight edge and router?

any input would be appreciated...
thanks
donnie

I have used some recycled acrylic from semi large tank builds that have gone south for some reason or an other. On all of them I have found the the acrylic has been bowed!! Lets say a 2' X 2' piece would not sit flat if you layed it down on a flat surface. Most all the pieces I salvaged were distorted in one way or another.
This is just my experience. Be prepared to do some extra work on your assembly to make the warped pieces work.

As for protecting the acrylic. I just taped on some heavy brown paper.

You could use a skill saw to cut the large pieces into smaller manageable pieces if you like. Just over cut it and allow extra to run it thru the tablesaw

 

[Acrylics]

i've got a couple questions about "recycling" some acrylic. i will most likely be purchasing an incorrectly built acrylic tank, and i'm planning on cutting it down and building a smaller tank with the bulk of the salvageable material.

my first question, what is the best way to protect the acrylic from scratches while i'm working with it? i was thinking masking tape and paper, but i have my doubts about that being the 'best' method.

my second question is about dismantling this thing... its a fairly large tank, and the idea of running it thru the table saw doesn't seem all that safe. straight edge and router?

any input would be appreciated...
thanks
donnie

Peppie's post said it all..
If the tank has been used at all, hope you're getting a really good deal on it - the acrylic will not be fun to play with. As Peppie said, it will be badly warped and that presents some challenges. If still new, should be much better.

There is a masking paper you can get at most sign shops. It comes in 12" wide rolls (and many other sizes; 18", 24", etc.) as long as you don't let it sit in the sun *at all* you'll be okay.

Router and straightedge, sawzall, skil saw, all work fine. Sawzalls will cause lotsa chattering, but still workable

James

 

[sick_bubblegum]

so what's the best way to cut out the top? i have a router but no router table. also, how should i cut the top to accomodate my overflow? i will have a 2" overhang. i can either build my overflow extra deep so i can get inside, or i can route out a hole so i can reach through it to get to the overflow. obviously, building the overflow extra deep and keeping the rim 2" all the way around would be easiest, but would is 'standard'? thanks.

 

[overflowin]

Thanks for the input... I hadn't considered warping before. I feel I'm getting a good deal on it, but I will inspect it and see how warped it is. Will I be able to see it before I dismantle it, or will it show after the pieces are separated?

 

[peppie]

Thanks for the input... I hadn't considered warping before. I feel I'm getting a good deal on it, but I will inspect it and see how warped it is. Will I be able to see it before I dismantle it, or will it show after the pieces are separated?

Depending on the age of the tank, you will see bowing right off the bat. However some of the parts may look like they are not warped, but when you cut them free from adjoining pieces you will release some stress and they will look much worse than when it was all together.

 

[karimwassef]

This may be slightly off-topic, but I would appreciate a link to a cost effective acrylic sheet resource. I need 0.5" 2'x4'. Please PM if you can't reply.

 

[Acrylics]

This may be slightly off-topic, but I would appreciate a link to a cost effective acrylic sheet resource. I need 0.5" 2'x4'. Please PM if you can't reply.

I'd look in the yellow pages under "Plastics; sheet rod & film" or something to this effect for distributors like Laird Plastics, or look under "plastic; fabricating, finishing, and decorating" for fabricators.

Buying online and having it shipped is not the best way to go IMO.. go local, pay $10 more, see the material before you buy, and avoid shipping. JMO

You should expect to pay ~$100 for the piece you are looking for in good material like Plex G, Polycast is better but far more expensive and not many stock it. I wouldn't buy any other material, period.

HTH,
James

 

[overflowin]

I have access to a very large, relatively low temp oven. If I heat it slow, and cool it slower on a large flat surface, will that "reset" the molecular structure and return it to its flat shape? If so, how long at what temp, and what kind of timeframe for cooling?

 

[YoungREEFA]

what can i use to attach acrylic sheets to glass, overflowbox

 

[peppie]

what can i use to attach acrylic sheets to glass, overflowbox

Interior box, or exterior box??

 

[Acrylics]

I have access to a very large, relatively low temp oven. If I heat it slow, and cool it slower on a large flat surface, will that "reset" the molecular structure and return it to its flat shape? If so, how long at what temp, and what kind of timeframe for cooling?

If you heat it up to a forming temp of 300+F (necessary to flatten) - you will probably get a good bit of mark-off from the oven and the sheets will *probably* not return to a completely flat shape.

If you heat acrylic in the oven to ~180-200 for 24 hours and then slowly cool it - you will help realign the molecular chains and avoid much of the mark-off, but probably little to actually flatten it... but it would help.

James