# Acrylic Project----Never used Router before



## mbrady (Apr 5, 2010)

I am building a 36L X 16W X 16H 3/8" acrclic aquarium. I want to use a router to finish the edges. I need to have the edges perfectly square in order for the joints to hold.
My plan is to use an old Sears router I inheriited (model # 315.17380). This router is in the neighborhood of 30 years old. I have the old router table but it appears to be nothing more than a two foot high table with a hole in the middle. 

*I would like a recomendation on a newer and more reliable router table that would accommodate this router.*

Add on top of this I am someone who has never used a router before and will have to learn how to use the equipment first.

Any advice would be greatly appreciated.


----------



## r32 (Feb 19, 2010)

I have limited experience using a router with acrylic and I currently am looking for a table too. But...be careful with the acrylic. Do some research on what bits specifically work well with acrylic. The guys from this company have been very helpful with acrylic projects that I've worked on in the past, and they make recommendations on how best to go about things.

TAP Plastics

They can also make custom cuts for you for a very reasonable price, and send you the acrylic.


----------



## timbertailor (Oct 4, 2009)

I have heard that some saw blades leave a clean enough cut to allow immediate joining without any additional work.

Just make sure that your table is 90 degrees to the bit or blade. This will go a long way to strong seals/joints.


----------



## jschaben (Jun 21, 2009)

mbrady said:


> I am building a 36L X 16W X 16H 3/8" acrclic aquarium. I want to use a router to finish the edges. I need to have the edges perfectly square in order for the joints to hold.
> My plan is to use an old Sears router I inheriited (model # 315.17380). This router is in the neighborhood of 30 years old. I have the old router table but it appears to be nothing more than a two foot high table with a hole in the middle.
> 
> *I would like a recomendation on a newer and more reliable router table that would accommodate this router.*
> ...


Hi Mike - Welcome to the forum
"I have the old router table but it appears to be nothing more than a two foot high table with a hole in the middle."
Sounds like it could be a functioning router table to me. 
Seriously, that table could probably me modified to make it perfectly good. Not knowing what the thing looks like I can't make any recommendations at this point. Modifying the table may give you an opportunity/excuse, to get familiar with the use of the router also.
My major concern is with your router and what you are planning on doing. A 30 year old Craftsman is likely a fixed speed, 25,000 rpm, 1-1/4 - 1-1/2 hp. When working with acrylic, I believe a variable speed unit is really a necessity. There are several good ones in the 2hp range on the market with variable speed. Many are priced reasonably, ie ~$150.
Well, anyway, first things first. Can you post a picture of your table and we can go from there?
If you are set on buying one, there are a lot to pick from. And a dizzying array of options, from nothing to everything (prices to match).
Keep us posted


----------



## eccentrictinkerer (Dec 24, 2007)

My brother is a machinist and is often asked to make acrylic guards to keep fingers out of the works.

He's fussy so his guards look as good as the machinery he builds. He uses a tablesaw/bandsaw to cut to size then uses several grits of sand paper to clean up the edges, ending with 400 or 600 grit.. 

After glue-up he 'flame polishes' the exposed edges to make them perfect. I'm sure there are a number of sites on the 'Interweb' that will explain these processes better than I have.

....
Just got off the phone with the bro. He says he only uses Lexan or equivalent. Lexan is much more scratch and crack resistant than acrylic.

He also says he can form the Lexan in the shop brake! I can't imagine bending any plastic without heat, so I'm going to have to visit his shop to see how he does it.

Good luck with your project and welcome to the forum!

J.D.


----------



## Charles Wong (Jan 5, 2009)

mbrady

I build sump and display tanks for money and there is a little trick to building a good tank with no bubbles.

Since this is your first tank, I would suggest building the sump first so if you screw up it won't be that bad. DO NOT use Weld-on #16 as that is for big gaps, like 1/16" but no bigger. Use Weld-on #4

Cut your plastic (hopefully it's at least plex G (clear cast) as Lexan is not for aquariums) 1/16" over size then route the sides taking small bits at a time. The trick is to rout all the pieces, all the same side, the same size.

Then when you are ready to assemble it 



















To answer your question, I mount my router like this, that is a 3 1/2hp Roybi RE600, that old Sears router has probably seen better days and IMO would not leave a good finish on acrylic.










24" cube








180gal








my current tank
My DIY 80gal reef - Reef-Solutions

And please don't flame polish the tank - this is bad advice from non aquarium builders. What happens is that you will change the molecular structure of the plastic and if you use a cleaner with ammonia it will start to crack and haze. Don't believe me just try it on a piece of scrap and see what happens. This is ok for other purposes not holding water.


----------



## BigJimAK (Mar 13, 2009)

Charles,

Do you have a recommendation for smoothing / polishing the edges, short of flame polishing? Ever-finer sandpaper until you get to 2500 grit or something lime that?


----------



## gav (Oct 12, 2009)

20 years ago when I was in high school, we would sand smooth and then use some buffing compound and of course a buffing wheel on a drill or grinder to polish the edge of acrylic.


----------



## Charles Wong (Jan 5, 2009)

The sandpaper is the only way to get a nice glass smooth finish. The wet/dry paper up to the 1500 grit, but I stop at 1200. After the sandpaper you can use a hand buffer (the one for cars) and some Novis acrylic polish to finish it off. 

But I'm too lazy for that and pay the wife to do it.


----------



## darkdun (Apr 18, 2010)

My experience with flame polishing is that the outcome is only as good as the sanding done first.


----------



## darkdun (Apr 18, 2010)

I have routed a 3/8 rabbet in polycarbonate but my router is not variable speed so you have to do many passes or the "shavings" will melt


----------



## tigerhellmaker (Sep 13, 2009)

For experiment I use sand blocks








After routing :
80 grid new
100 grid old
240 grid old
Surface looks really nice so I buy water paper 1000 & 4000 grid for better effect. Using that I destroy surface :/


----------



## almosta7ftr (Jul 29, 2010)

Sorry for the late post on this thread, but I just stumbled on it. 

Years ago (more than it seems or that I care to admit to) I spent about 4 years building custom acrylic aquariums and filtration stuff, including the qurantine tanks at the Denver Zoo's Tropical Discovery display.

To answer your first question about the edge to be glued, this is how I would tackle the problem:
First, cut the front, back and side panels on the table saw using the same setting for the panel height, but cut them about 1/16th wide (tall if assembled). Use an 80t carbide blade with a tripple chip tooth. You can then cut them to width, but leave the front and back a bit long because you flush trim them later.

Second run the front, sides and back through the router table to smooth the edges that will be glued and to cut to final dimension.

Then run the sides thru router table to finish remaining two edges on the sides.

If done correctly, the front, back and sides will all have identical height dimensions and the sides will have identical widths.

Glue the sides to the front. I always used Weld-on #3 for cast acrylic and #4 for extruded sheet or tube. A quick tip is to use a right angle jig to hold the side vertical, and place small diameter wire under the side panels to create a very narrow gap to allow the water thin glue to "suck up" under the joint. Make sure that the top and bottom edges are absolutely flush! Then glue the sides to the back using the same method.

You should now have a 4 sided box and you should be able to run your fingernail all the way around the top and bottom edges without noticing the joints.

Now get your top and bottom ready - they should be cut about 1/16th long and wide because you are going to flush trim them once they are glued on. 

When cutting your top, cut the access hole(s) out with a template and flush trim bit first!

Once the top and bottom are glued on, let the glue joints set up for a few hours , then flush trim the top and bottom, then the front and back to the sides.

Then you can profile route the edges with a round-over bit. ( I would just do the joints where the sides meet the front - not every edge because most aquariums will have a lid that covers the top edges and will sit in a base or on a flat surface and a rounded over bottom edge seems awkward there)

Now the million dollar question - To flame, or not to flame...

I always flame polished my edges. I did this because I worked in a commercial setting and spending the time to sand and polish was unthinkable. It is true that you can induce crazing in the acryic by flame polishing, but only if not done correctly. Here is the secret: I used an acetylene/oxygen torch - very HOT! With that setup, you move very fast so that only the very surface of plastic gets any heat. If you linger in one spot or go to slow, you will quickly boil the plasic and ruin the piece.
If you try to flame polish with propane, you can't get enough heat, so you end up going slower wich heats up the plastic deeper. In other words - if you use propane, buy the time the edge gets hot enough to polish over, you have heated it to the point where it will be hot to the touch for a while, but with Oxy/Acetylene, the edge will be cool to the touch immediately.

Without the O/A rig, I would route the edge, profile the edge then sand the edge to 320then polish with a wheel and some compound, but be careful with the wheel because you can generate enough heat to cause the same problems that you get with a propane torch.

Hope someone out there finds all of this usefull.


----------



## mbrady (Apr 5, 2010)

Thank you for the response. My first attempt was not a success but I am learning.

Response from original post


----------



## toolgle (Sep 21, 2010)

I would recommend a spiral cutter and use a ptfe spray to lube as acrylics stick to the tools. Some manufacturers can adjust TCT tooling with a finer grit diamond polishing wheel giving a sharper edge. HSS tooling is a good option too.

more router tips are here


----------

