BeanAnimal
Premium Member
Ahh very interesting concept...
I think it, adapted to the fiberglass grid conbcept, would be a very viable option as well.
Last edited:
Acrylic fabrication questions? I can help!
- Thread starter JohnL
- Start date
Ahh very interesting concept...
I think it, adapted to the fiberglass grid conbcept, would be a very viable option as well.
Floyd R Turbo
Either busy or sleeping
Regarding water absorption, IIRC cell cast will absorb roughly 1% of it's weight in water over time (14 weeks I think) and extruded will absorb 60% more than cast or roughly 1.6% so it's pretty negligible.
James (or anyone else who knows) I have another chemical question. On the smaller bottles you use when you mix and store MC and AA short term, what caps do you use? Just a plain white plastic one or teflon coated, etc? Trying to figure out what to get for storing smaller amounts of MC and AA separately, and mixed
James (or anyone else who knows) I have another chemical question. On the smaller bottles you use when you mix and store MC and AA short term, what caps do you use? Just a plain white plastic one or teflon coated, etc? Trying to figure out what to get for storing smaller amounts of MC and AA separately, and mixed
dahenley
New member
BEAN: the grid is a great suggestions if using a foam to cover the holes. Plus, you wouldn't have to drill homes for securing.
When building, you might try to not make a perfect 90 degree angle. More of a 95+ degree would be better, as it would wedge in the tank. If the bottom touches the front. If not, the a 90 would be better.
When building, you might try to not make a perfect 90 degree angle. More of a 95+ degree would be better, as it would wedge in the tank. If the bottom touches the front. If not, the a 90 would be better.
BeanAnimal
Premium Member
It would also allow easy attachment (due to the structure) of the tracvertine or whatever "tile" he is looking to incorporate.
It is a typical weld, but MEK generally produces weak joints. That said, when I did mine - I compared several joints using PVC pipe cement, straight MEK, and several others gluing flat sheet to flat sheet (similar to laminating) in ~3 square in areas. None would break on break tests, period.
One thing to keep in mind when looking a PSI ratings and whatnot is that chemical welds stress acrylic and this weakens the material to varying degrees based on the properties of the solvent.
As an example; PVC pipe cement (primarily THF) creates "glued" bonds as THF does not dissolve acrylic but does stress the hell out of it, so more apt to craze. In this case, while the bond is strong, the acrylic becomes weaker than the "advertised" 10,000psi rating so the acrylic cracks before the bond. And all solvents will do similar, again to varying degrees as that is the nature in which they work - they stress the material into solution.
Even "soak times" will affect material in similar fashion using any given solvent. An acrylic bond with a 15 second soak time can be much stronger than a 2 minute soak time. While actual "joint strength" may be similar - the acrylic becomes more stressed with the longer soak time, therefore weaker.
These are the types of things that IPS nor Cyro nor anyone else goes into so I personally don't give much credence to any of their specs.
And yes, acrylic shavings can be added to any acrylic solvent to thicken it
Using 16 on a PVC bulkhead fitting produces a similar effect. Because it's (16) is thickened, it will stick to damn near anything, but it is not "biting" into the PVC enough to make a chemical bond. Please keep in mind I'm referring to PVC (Sch80) bulkheads. If you call Cyro or IPS or whatever, they might be referring to the standard ABS bulkhead fittings which methylene chloride will certainly bite into. Acrylic being the primary component of ABS
HTH,
James
Lotsa companies use extruded tube for skimmers, I don't care for the practice, but it is done.
That said, there is a *huge* difference between extruded sheet stock and tube stock. Tube stock is under far more latent stress and will melt on a table saw far faster than sheet stock and has a far lower mole weight which means it cannot handle the stresses than cast tube can.
Ok, so what does this mean... it means that extruded tube is *far* more apt to craze than cast tube, or even extruded sheet stock. It is not at all uncommon for DIYers to cut extruded tube and overheat the material such that when solvent is applied - it crazes on contact, thus produce a likely point of failure.
So, yes, it is a viable option, but one has to be careful when using it, do not over heat it, do not soak it too long, etc etc...
James
It is a typical weld, but MEK generally produces weak joints. That said, when I did mine - I compared several joints using PVC pipe cement, straight MEK, and several others gluing flat sheet to flat sheet (similar to laminating) in ~3 square in areas. None would break on break tests, period.
One thing to keep in mind when looking a PSI ratings and whatnot is that chemical welds stress acrylic and this weakens the material to varying degrees based on the properties of the solvent.
As an example; PVC pipe cement (primarily THF) creates "glued" bonds as THF does not dissolve acrylic but does stress the hell out of it, so more apt to craze. In this case, while the bond is strong, the acrylic becomes weaker than the "advertised" 10,000psi rating so the acrylic cracks before the bond. And all solvents will do similar, again to varying degrees as that is the nature in which they work - they stress the material into solution.
Even "soak times" will affect material in similar fashion using any given solvent. An acrylic bond with a 15 second soak time can be much stronger than a 2 minute soak time. While actual "joint strength" may be similar - the acrylic becomes more stressed with the longer soak time, therefore weaker.
These are the types of things that IPS nor Cyro nor anyone else goes into so I personally don't give much credence to any of their specs.
And yes, acrylic shavings can be added to any acrylic solvent to thicken it
Using 16 on a PVC bulkhead fitting produces a similar effect. Because it's (16) is thickened, it will stick to damn near anything, but it is not "biting" into the PVC enough to make a chemical bond. Please keep in mind I'm referring to PVC (Sch80) bulkheads. If you call Cyro or IPS or whatever, they might be referring to the standard ABS bulkhead fittings which methylene chloride will certainly bite into. Acrylic being the primary component of ABS
HTH,
James
Ah..... that explains some of what I'm seeing. I toyed with MEK yesterday and wasn't impressed by it except for it's ability to cause crazing.
Now, my MEK was old, so there is no telling if it's gone bad..... Quick question on tank testing: I saw that you recommend a curing period of a couple of weeks, which makes sense......I'm probably going to give the joint from the bottom to the sides 10 days to cure. The sides will be around 2 weeks old at that point.
When I go to test the tank I had planned on doing it in my garage. The garage floor is not perfectly flat, it's close, but it's a floor. Would a sheet of 3/4" foam be enough to protect the tank or do I need to do my testing somewhere else? The main reason for the garage is it's climate controlled and I can keep the tank at a reasonable temperature in case our weather gets nasty. I think the floor is just simply uneven to the tune of a 1/8" or 1/4" over the 8' run. It's flat enough to run pallet jacks over with no real issues, but water will form very thin puddles if we wet down the whole floor.
How long should I allow the water test to go on before declaring the tank "done"?
IMO/IME, styrofoam underneath is pretty much useless for acrylic tanks. Due the the nature of how it compress (or doesn't) - it doesn't do anything beneficial for our purposes. If anything, neoprene is better, but far more expensive
It doesn't matter where it's tested provided the bottom is *fully* supported.
IMO, if it holds water for a minute, it's done. If your joints are shotty or suspect, re-do the joints rather than testing for a month. But if the joints are good and clean and the tank holds water - it's done IMO/IME
James
Floyd R Turbo
Either busy or sleeping
James, do you have a 'standard' for how long you wait to fill a tank/sump with water (for use)? Longer for thicker material? Based on joint technique (solvent vs 40/42)?
How long for this sump that I just got done: All 3/8" Plex-G, MC/10%AA solvent joints, 1/4" bottom
Joint close-up (before flush trim/round)
a few other shots
How long for this sump that I just got done: All 3/8" Plex-G, MC/10%AA solvent joints, 1/4" bottom
Joint close-up (before flush trim/round)
a few other shots
Floyd R Turbo
Either busy or sleeping
Flash effect. rounded the edges with a 1/8" bit and didn't polish it (and probably won't)
dahenley
New member
looks good! (kind of the same design i am going to make when i get my other tank re-sealed)
Floyd:
do you think the DIY solvent flowed/worked as good/better/same/less effective as standard IPS WO3/4
just curious as to your opinion. (the seam in pic 1 looks sweet and bubble free)
Floyd:
do you think the DIY solvent flowed/worked as good/better/same/less effective as standard IPS WO3/4
just curious as to your opinion. (the seam in pic 1 looks sweet and bubble free)
dahenley
New member
looks good! (kind of the same design i am going to make when i get my other tank re-sealed)
Floyd:
do you think the DIY solvent flowed/worked as good/better/same/less effective as standard IPS WO3/4
just curious as to your opinion. (the seam in pic 1 looks sweet and bubble free)
Floyd:
do you think the DIY solvent flowed/worked as good/better/same/less effective as standard IPS WO3/4
just curious as to your opinion. (the seam in pic 1 looks sweet and bubble free)
Floyd R Turbo
Either busy or sleeping
Correction: I meant 5% Acetic Acid, not 10%...
I have used #3 and #4, I think #4 is better because you have a little more working time. The DIY solvent flowed exactly the same IMO but the nice thing was the AA extended the working time. This was particularly beneficial when I stopped short on one joint and had to add a little solvent, and forgot to get the solvent through the needle and shot air into the joint. Duh. I then proceeded to try and work the bubbles out of the joint which resulted in accidentally pulling the joint apart and introducing a massive amount of bubbles. By first exhaling a string of expletives and then working quickly, I was able to clear the joint of almost all bubbles and still end up with a nice joint. (edit: it was a different joint) There are still a few bubbles like these:
But to me that was completely acceptable considering the alternative of re-doing the tank.
I have used #3 and #4, I think #4 is better because you have a little more working time. The DIY solvent flowed exactly the same IMO but the nice thing was the AA extended the working time. This was particularly beneficial when I stopped short on one joint and had to add a little solvent, and forgot to get the solvent through the needle and shot air into the joint. Duh. I then proceeded to try and work the bubbles out of the joint which resulted in accidentally pulling the joint apart and introducing a massive amount of bubbles. By first exhaling a string of expletives and then working quickly, I was able to clear the joint of almost all bubbles and still end up with a nice joint. (edit: it was a different joint) There are still a few bubbles like these:
But to me that was completely acceptable considering the alternative of re-doing the tank.
DustinB
New member
Hey guys, I've been trying to track down some decent material locally for a decent price. Most everyone wants to charge me freight for Plexi-G or Polycast, they only stock no name. I did find one place that had great pricing on something I am unsure about.
It is unmarked brown paper masking, but, she said their invoice shows "Atofina - General Purpose". From what I read in this thread, Atofina is the same place that makes Plexi-G. Any ideas if this could be unmarked Plexi-G or any idea what it could be? It has a better price than Acrylite GP.
It is unmarked brown paper masking, but, she said their invoice shows "Atofina - General Purpose". From what I read in this thread, Atofina is the same place that makes Plexi-G. Any ideas if this could be unmarked Plexi-G or any idea what it could be? It has a better price than Acrylite GP.
Floyd R Turbo
Either busy or sleeping
BTW, big thanks to James and the other acrylic gurus on this site, without all of their advice, I don't think I would ever have been able to get close to this quality of work.
Through this build I made a few minor mistakes. There's no getting around that I don't think. I knew exactly what I had done wrong, because I read about it on this thread. But sometimes you can't learn what to do right until you do it wrong! Luckily, none of the mistakes I made were deal-breakers, and I have learned from them, as I'm sure I will continue to learn.
Next I am building a 30g frag tank, an 18g sump for a 29 biocube, a 30g sump/fuge/ATO, and then probably a 45g sump/fuge
Through this build I made a few minor mistakes. There's no getting around that I don't think. I knew exactly what I had done wrong, because I read about it on this thread. But sometimes you can't learn what to do right until you do it wrong! Luckily, none of the mistakes I made were deal-breakers, and I have learned from them, as I'm sure I will continue to learn.
Next I am building a 30g frag tank, an 18g sump for a 29 biocube, a 30g sump/fuge/ATO, and then probably a 45g sump/fuge
Floyd R Turbo
Either busy or sleeping
Arkema make Plexiglas, I believe Atofina is their european parent company or sister company.
If you look back in this thread a few weeks, I asked about this. Plex makes an unprinted version of their material that apparently is a "spec grade" material, meaning that it is of slightly lover quality than that with the printed mask, so it might have a higher incidence of black specs and inclusions in the material. I asked James and he said there is no concern whatsoever.
I asked my local Regal plastics if they could get this version in stock, and they said they would not. They carry the printed mask stuff (so it exists) at 20% more and they said they use it for museum display, etc so it needed to be top quality. The joke is on them though 'cause I can't find ANYTHING wrong with this stuff.
I would do what I did - get your supplier to call up their Arkema rep and verify that it is indeed Plexiglas-G, spec grade is what I was told. If that's what it is, you're good to go. I think that's exactly what it is - "General Purpose" sounds vaguely familiar.
All my 1/4" stuff has the mask. Trying to get my supplier (who got me the unprinted 3/8") to see if they can get that in unprinted for cheaper...
If you look back in this thread a few weeks, I asked about this. Plex makes an unprinted version of their material that apparently is a "spec grade" material, meaning that it is of slightly lover quality than that with the printed mask, so it might have a higher incidence of black specs and inclusions in the material. I asked James and he said there is no concern whatsoever.
I asked my local Regal plastics if they could get this version in stock, and they said they would not. They carry the printed mask stuff (so it exists) at 20% more and they said they use it for museum display, etc so it needed to be top quality. The joke is on them though 'cause I can't find ANYTHING wrong with this stuff.
I would do what I did - get your supplier to call up their Arkema rep and verify that it is indeed Plexiglas-G, spec grade is what I was told. If that's what it is, you're good to go. I think that's exactly what it is - "General Purpose" sounds vaguely familiar.
All my 1/4" stuff has the mask. Trying to get my supplier (who got me the unprinted 3/8") to see if they can get that in unprinted for cheaper...
