Custom Router Vacuum Attachment Part 1

I've been planning to do quite a bit of wood working over the coming months and some of it using MDF.  If you've ever worked with MDF, you know that cutting or routing it throws dust everywhere.  It shows up in places you didn't even know that dust could get to.  Now I have 2 routers, a table-mounted one and a non-table-mounted one.  The non-table-mounted one is very old, at least for a power tool.  Probably 2000 or 2001. (though it could be several years older)  That said, it is still in good working condition and does the job I need it to.

It is missing 2 features I wish it had.  The first is variable speed. There isn't much for that, it doesn't have it, that's life.  The other feature is a lack of a dust collection port.  This one is more important to me.  My garage pulls double duty as a car port and shop, so things that reduce the amount of dust I'm putting out while working are welcome.  Given the tool's age, there isn't much out there that will do the job of adding the dust collection to it.  To that end, I'm attempting to build my own system that will do the job.

 

So first we start out with the router itself.  There is a normal base not shown here that I'm going to replace.  Firing up LibreCAD, I started to the work of designing the pieces.  I knew I wanted to build it out of acrylic.  It is what I had on hand and I have done work in acrylic before (Custom Acrylic Submerged PC ).

There were 3 pieces to build.  The bottom (top left), middle (top right), and top (bottom left).  The center hole is, as you might guess, where the bit goes.  There is then a channel that sits in the middle out to a hole on the top.  The notion here is that the vacuum goes in the top hole and pulls through that channel.  (this is the step where I wish I had a CNC Milling machine, but sadly those are expensive and I'm trying to save myself 200$, not 2000$ :) ).

At this point the first order of business was to create a template in plywood that I could use to create all 3 of the pieces.  Most of the template I cut with the router except the straight parts with I did by hand with a jigsaw.  There is a little bit of a bend on the inside channel, but since it is going to be sandwiched in between I wasn't terribly concerned.  (Since this is a prototype experiment anyway.).

I then added a few holes to use as a clamping method to cut out the acrylic.  This was done entirely with a router and a flush bit that is designed for doing acrylic. (Same bit I used on the case I built).  I used a hole saw for the larger holes on the left and right.

Then all that was left was to drill new holes that match the old one and put it together to see how it all fit.

After fitting, I took a blow torch to all the sides to polish it and give it a shiny finish.  Then attached it to the router and stuck the vacuum port on it. To test fit.

That looked pretty good I thought.  The only problem was that the vacuum attachment was slightly smaller than what it said it was when I bought it. (Supposed to be 1.25" but was closer to 1.2" at the base due to a taper).  I put a line of silicon and put it back in and let it set.

Unfortunately this is where I'm stuck at now.  I tried attaching the hose, but found that the pulling stress was too much which yanked the vacuum attachment right out.  So I'm currently considering how best to combat this.  I have a couple of thoughts.  My first is to get a piece of acrylic tube that has an inside diameter of 1.25" and another piece of 1/4" acrylic and weld the tube to that piece and then that piece to the top where the outside hole is.  This would give a longer place to put the hose in.  The other option is similar but include somehow bending the tube 90 degrees to reduce the amount of stress the vacuum hose adds.

Right now I'm just not sure where to go next with it.