Trackball mounting -- 3" hole cutting bit? (what else can I use?)

[sofakng]

Tonight I cut out everything for my control panel on my father's drill press.  It came out really nice!  There is only one thing left to cut out -- the trackball.  I'm using a Happ's 3" Golden Tee trackball.  So, I need a 3" hole cutting bit to cut out a spot for it.

We don't have any 3" hole cutting bits.

Can I use anything else to cut this out?  My father suggested using a jigsaw but if I use that it will come out TERRIBLE espicially when we go to cut the plexiglass, right?

Anybody have any suggestions for me?

I really don't want to spend $15 or $20 on a bit I'm only going to use one single time for one single hole...

[whammoed]

I know rotozip has an optional circle cutting attatchment.  Do you have one, or know someone who does?

[stuzza]

I just used a Jigsaw to cut out the hole in the plexi for my trackball.  It worked a treat!  I used the trackball mounting plate as a guide and pre-drilled 4 holes with a standard drill bit first.  Then just use sandpaper to give it a nice edge.

You can see photos of how I did it here:
http://www.screenshotarchive.com/cabinet/cp_2.htm

[sofakng]

Hmmm, maybe I'm a bit confused then...

In your top picture it looks like you cut out only the trackball hole, but in the bottom pictures it looks like you cut out the entire trackball area (the rectangle-type shape).

Do you cut the rectangle shape in the MDF, and the hole in the plexiglass?  That would make sense I think.

Also, I'm guessing that you recessed your trackball mounting plate so it was flush on top?  Any tips on this?  How about the bottom, did you recess the trackball so it stuck up higher?

[Hoopstar]

Stuzza - good to see another Aussie on the boards  and very nice job btw..!!


Just a couple of questions:

- Where did you get your trackball mount plate from??

- What depth did you route the CP for the joysticks? what was the thickness of the material left when you finished?  And does it feel solid enough..?  (I am doing the same thing but am worried about breaking the MDF when my rough mates come over..

[Totallyout2lunch]

If your going to use a Track Ball Mounting Plate (got mine from Happs UK), you do not need a 3" hole for the Track Ball, (you will need one if you use Lexan or some other finnish for youe CP.

To cut my 3" hole I borrowed a 3" plummers hole cutter, (UK

[ThePaul]

Hmmm, maybe I'm a bit confused then...

In your top picture it looks like you cut out only the trackball hole, but in the bottom pictures it looks like you cut out the entire trackball area (the rectangle-type shape).

Do you cut the rectangle shape in the MDF, and the hole in the plexiglass?  That would make sense I think.

Also, I'm guessing that you recessed your trackball mounting plate so it was flush on top?  Any tips on this?  How about the bottom, did you recess the trackball so it stuck up higher?

You are going to want to cut the football shaped hole in your MDF, route a square in the top of the CP so your mounting plate sits flush, then when you put your plexi over the top you will need a 3 inch hole for the ball to stick out.

You don't need a 3" hole bit, you need to use your flush trim bit on your router or if you decide to take the plexi to the glass shop like you were talking about just screw the mounting plate to the CP so they have the hold in it as a guide.

[FractalWalk]

You don't need a 3" hole bit, you need to use your flush trim bit on your router

I'm not sure that this will work.  I secured  plexi to the top of my panel with the trackball plate underneath.  I flipped the whole thing over and grapped my router and pattern bit.  The problem that I ran into is that the mounting plate is only about 1/16" wide and the cutting edge of the bit was farther away from the arbor than that. So while the arbor rode along the edge of the mounting plate, the cutting edge of the bit was too deep to cut the plexi.   (See image:  red = inverted CP, Black = mounting plate, Lt blue = pattern bit, Dk blue = arbor)

To fix this, I would have had to space the plexi farther away from the control panel (e.g. stick a piece of wood between the plexi and panel), but then I couldn't be sure that my plexi lined up exactly with my panel.

I ended up free-handing the router and cutting out as much of the 3" area as I could using the plate as a visual guide. What I was left with was a very rough circle-ish like hole. I then used sandpaper to sand the edge of the hole out to meet the trackball plate.  

It came out great, but I'm sure there had to be an easier way.

[stuzza]

Hmmm, maybe I'm a bit confused then...

In your top picture it looks like you cut out only the trackball hole, but in the bottom pictures it looks like you cut out the entire trackball area (the rectangle-type shape).

Do you cut the rectangle shape in the MDF, and the hole in the plexiglass?  That would make sense I think.

Also, I'm guessing that you recessed your trackball mounting plate so it was flush on top?  Any tips on this?  How about the bottom, did you recess the trackball so it stuck up higher?

If you are going to flush mount the panel so only the ball is visible from the top (which in my opinion is the only way to go!) then as others have said, you only need to cut the 3" hole in your plexi, assuming you are using a plexi overlay.  Basically you can just use a jigsaw to cut out enough of the MDF to fit the trackball to attach to the mounting plate.  

You can see in the pics here: http://www.screenshotarchive.com/cabinet/cp_1.htm  (see bottom of the page)  which areas are cut out and the routed area on the top side to enable the mounting plate to sit flush with the top of the mdf.  You don't need to do any routing from the underside.

Hoopster: I bought the mounting plate from Happs when I got the trackball.  The joystick areas were routed out so there is about 8mm of MDF left - from memory?  I have made 3 cabinets using this thickness and have never had one break - and believe me they've had some heavy handed testing!

[sofakng]

stuzza, you used a jigsaw to cut the section out of your mdf, right?  What did you use to cut the hole out of the plexiglass?

FractalWalk, I'm not sure why you had that problem... If you use a plunge router (like I have) can't you just adjust the depth so the bit lines up perfectly?

If I make the mounting plate flush (recessed into the mdf on top), then the plexiglass will lay flat on top of the mdf.  Then when I flip it over (so plexiglass is on the bottom), can't I just let the plunge router ride the circle in the mounting plate to get the perfect circle?

I'm going to be making this cut tonight, so any additional help would be GREATLY appriciated.

[FractalWalk]

FractalWalk, I'm not sure why you had that problem... If you use a plunge router (like I have) can't you just adjust the depth so the bit lines up perfectly?

Look again at my picture to see if my explanation makes sense. The router bit arbor (dk blue) is riding along the trackball plate (black) that is flush mounted to the CP (red). See how the cutting edge of the bit (pink) is too low and it misses the plexi (green outline). If I adjust the bit up so that the cutting edge hits the plexi, then the arbor will be above my trackball plate and I would be free-handing it.

I also ran into issues of the mounting posts getting in the way of my router but perhaps that is a router specific problem.  I ended up securing the plexi on top of the CP (right-side up) and using the trackball plate as a visual guide, I free-handed the route as close to the plate as I could. Then I sanded the edges out until I was happy with the output. It actually came out quite nicely, but I never heard of anyone else having to do this and so I'm thinking there has to be a better way.

 

[sofakng]

Ok, I see what you're saying now.  I'm very new to routers so I don't understand how everything works yet...

Could you possibly cut right to the mounting plate, or is that really bad for the bit?  I'm guessing that if I tried this it would totally destroy the bit...

Also, how did you cut the trackball circle out of your artwork?  I have another thread about this and I've gotten some suggestions, but I'm wondering how you did it.

[ThePaul]

FractalWalk, I'm not sure why you had that problem... If you use a plunge router (like I have) can't you just adjust the depth so the bit lines up perfectly?

Look again at my picture to see if my explanation makes sense. The router bit arbor (dk blue) is riding along the trackball plate (black) that is flush mounted to the CP (red). See how the cutting edge of the bit (pink) is too low and it misses the plexi (green outline). If I adjust the bit up so that the cutting edge hits the plexi, then the arbor will be above my trackball plate and I would be free-handing it.

I also ran into issues of the mounting posts getting in the way of my router but perhaps that is a router specific problem.  I ended up securing the plexi on top of the CP (right-side up) and using the trackball plate as a visual guide, I free-handed the route as close to the plate as I could. Then I sanded the edges out until I was happy with the output. It actually came out quite nicely, but I never heard of anyone else having to do this and so I'm thinking there has to be a better way.

 

Fractal if your picture  is somewhat to scale.. couldn't you have attached the mounting late from the bottom of the cp and left the plexi on the top. This would give a gap between the cutitng surface and the template surface... I think your problem might be related to the bit though as it seems there should be some bits with no space between cutting area and bearing?

[FractalWalk]

Could you possibly cut right to the mounting plate, or is that really bad for the bit?  

That's basically what I did, but I avoided hitting the metal as that would be bad for both bit and mounting plate. This left a rough not quite circular edge. Sandpaper took care of the rest.


Also, how did you cut the trackball circle out of your artwork?

I just responded to your other thread, but to re-iterate I basically mounted it first and used an exacto to cut along the plexi hole underneath.  If your plexi is on top of your art, then you could use the mounting plate as a guide.



couldn't you have attached the mounting late from the bottom of the cp and left the plexi on the top.

Unfortunately, the mounting legs get in the way. But If I had drilled precise holes in the plexi where the legs could stick through then, yes that would have worked.  



I think your problem might be related to the bit though as it seems there should be some bits with no space between cutting area and bearing?

I'm thinking you may be right, but both my trim and my pattern bits have that gap.

[GadgetGeek]

If you have a drill press, http://www.rockler.com/findit.cfm?page=2393
I have one of these, but didn't pay near that amount so check locally at Lowes/Menards/HomeDepot to see what is available.
However, I think the flush bit with a router is the better way to go.  If there is the gap problem on the bit, temporarily add some spacers between the CP and the mounting plate to fix that problem.