DIY Sump Thread

George Lopez · Aug 11, 2017

Ok that's not fair you guys have some beautiful craftsmanship I your sumps

Mine is a 10 gallong glass tank with 1/4" acrylic siliconed on i had major size restrictions spitfire its a bit tight but i got everything in there

This is the design for my new 30 gallon sump on the 90 I'm setting up. But same style glass with acrylic

Dom · Aug 11, 2017

litenyaup said:
This was the setup I build about 5 years ago for my custom 189 gallon build. Local acrylic shop is going out of business so I picked up some stuff for a great price!! Can't wait to get started.

I have a question related to sump fabrication using acrylic:

How do you cut it without melting?

I've built several sumps, but have always used glass fish tanks with glass baffles cut at the local glass shop.

So again:

- Are you cutting on a table saw?
- What type of blade do you use?
- How are you joining (what adhesive)?

TaylorPilot · Aug 11, 2017

If you are making straight cuts and it is 1/4" you can typically score it with a box blade using a straight edge as a guide and snap it. To solvent weld it though, that method won't work because you have to have a perfectly straight machined edge. You can get away scraping it with a flat blade, but this manual technique isn't consistent because it requires that you remain perfectly perpendicular to the edge. The generally approved method is to use a router with a twin fluted bit. You would use a fence opposite the blade with the piece in the middle and shave off approx 1/8". That will prep your surfaces for welding. Then you have to seam the two pieces together. They need to be shimmed so that they have the exact same gap along the seam when welding. Typically you would put a series of metal pins along the seam to create a gap for the solvent to wick into the seam, allowing it to soften up the material before pulling the pins and mating the surfaces allow them to cure. There is also a very specific series that acrylic sumps have to be welded together. The two end pieces have to be exactly the same, and the front and back pieces have to be the exact same height as the sides. The top and bottom are over sized, and flush routed to make it all look right. There a few very long threads around the internet. Google acrylic pin method. It is pretty involved to get a good seam, but once you have the proper technique and equipment to do it, it gives very consistent results. If I was trying to make just one sump for the purpose of saving money, I would just go out and buy the most expensive custom sump you can find, and you'd probably come out ahead! LOL But if you want to do DIY for the sake of learning and building your own, I say go for it. It will take a bit of research, and a little trial and error, but it isn't impossible with a little bit of equipment.

George Lopez · Aug 11, 2017

Dom said:
I have a question related to sump fabrication using acrylic:

How do you cut it without melting?

I've built several sumps, but have always used glass fish tanks with glass baffles cut at the local glass shop.

So again:

- Are you cutting on a table saw?
- What type of blade do you use?
- How are you joining (what adhesive)?

I used a table saw with a fine tooth blade and it didn't melt. And will use that same method for my next sump. It also gave me an edge that i was able to weld together

bottled-ocean · Aug 12, 2017

Landy · Aug 12, 2017

Sheldon Jessup said:
Why Screws? i just noticed you put screws in the top panel?

The screws are so the top panel can be removed, allowing all but 2 inserts to be removed. Also, the screws are grade 5 titanium. This will allow the sump to be cleaned easily.

Landy · Aug 12, 2017

Dom said:
Wow... nice job! I love the modular concept.

thank you, I'm glad you like it!

Landy · Aug 12, 2017

JoshH said:
My guess would be for cleaning purposes, super easy to just unscrew the top and wipe off any salt creep. He did mention something about some baffles being removable as well. Some awesome build's here I wish I had the cash for all these fancy manufacturing toys, sorry, machines

you would be correct! the cnc machine is an investment for sure, but if you enjoy building things it is worth it.

landy

Dom · Aug 12, 2017

TaylorPilot said:
If you are making straight cuts and it is 1/4" you can typically score it with a box blade using a straight edge as a guide and snap it. To solvent weld it though, that method won't work because you have to have a perfectly straight machined edge. You can get away scraping it with a flat blade, but this manual technique isn't consistent because it requires that you remain perfectly perpendicular to the edge. The generally approved method is to use a router with a twin fluted bit. You would use a fence opposite the blade with the piece in the middle and shave off approx 1/8". That will prep your surfaces for welding. Then you have to seam the two pieces together. They need to be shimmed so that they have the exact same gap along the seam when welding. Typically you would put a series of metal pins along the seam to create a gap for the solvent to wick into the seam, allowing it to soften up the material before pulling the pins and mating the surfaces allow them to cure. There is also a very specific series that acrylic sumps have to be welded together. The two end pieces have to be exactly the same, and the front and back pieces have to be the exact same height as the sides. The top and bottom are over sized, and flush routed to make it all look right. There a few very long threads around the internet. Google acrylic pin method. It is pretty involved to get a good seam, but once you have the proper technique and equipment to do it, it gives very consistent results. If I was trying to make just one sump for the purpose of saving money, I would just go out and buy the most expensive custom sump you can find, and you'd probably come out ahead! LOL But if you want to do DIY for the sake of learning and building your own, I say go for it. It will take a bit of research, and a little trial and error, but it isn't impossible with a little bit of equipment.

The trouble with cutting plexiglass is that it melts from blade friction. Does acrylic melt when you cut it with a power saw?

BeelzeBob · Aug 12, 2017

My little 10g under a 17g display

TaylorPilot · Aug 13, 2017

Dom said:
The trouble with cutting plexiglass is that it melts from blade friction. Does acrylic melt when you cut it with a power saw?

Plexiglas is acrylic. It is just a brand name for an acrylic produce by Arkema. You have to use the proper blade to cut it with. For a circular saw blade, you want something with a "triple chip tooth". I have used a 7.25" Diablo blade in a Skil circular saw and have cut 100s of feet with the same blade, and it still cuts like butter. The edges are almost smooth enough to solvent weld. I usually just have to run them by a router blade just to shave off a tiny bit, and they are ready to go. I went and checked the No. on the blade, and it is this one. They make larger ones for miter saws, and/or table saws.

http://www.diablotools.com/products/product/D0756N

TaylorPilot · Aug 13, 2017

I should also add that the blade is a little expensive, so if you do get one, don't wear it out cutting wood or PVC. Although it is designed for cutting PVC, it is allot rougher on the blade than PMMA (acrylic).

Fudsey · Aug 13, 2017

Has anyone with a glass sump/baffles tried to have a piece cut down after it was installed? I want to lower the water level in one of my chambers but the baffles are installed. Is it possible to cut one down without removing it?

The circled one is the one I am referring to

Dom · Aug 14, 2017

TaylorPilot said:
Plexiglas is acrylic. It is just a brand name for an acrylic produce by Arkema.

I did not know this.

Even Further · Aug 28, 2017

Just finished this. Made from free glass from a broken tank.

Landy · Sep 6, 2017

Got the sump up and running a few weeks ago. Still have a lot that needs to be done. I'm really liking how the covers came out. First I made them from clear acrylic but didn't like the look.

landy

Dom · Sep 7, 2017

Landy said:
Got the sump up and running a few weeks ago. Still have a lot that needs to be done. I'm really liking how the covers came out. First I made them from clear acrylic but didn't like the look.

That sump looks GREAT! Hope it functions as well as it looks. But I still don't understand the use of anything other than clear acrylic as a building material. If something was going on inside the sump, you wouldn't know it unless you decided to open a compartment and look inside.