Cutting trackball hole in plexiglass (revisited)

[sofakng]

Just a little bit of an update for those wondering...

I've cut nearly every hole in my plexiglass using a laminate/trim router bit.  It works PERFECTLY.  I'd very highly recommend them for anybody needing to cut holes in plexiglass to match holes in MDF.  I haven't seen the actually plexiglass yet (the brown protective paper is still on it), so I'm praying that once I remove the brown paper there are no cracks or anything...  I'll let you know how I make out

However I still one hole left -- the dreaded trackball hole -- the only completely visible hole in the plexiglass (all other holes have buttons with lips, joystick washers, etc).

Today I bought a 3" hole cutter bit ($30 !!!  Home Depot said I could return it if "it doesn't work" even after I use it, heh)...  So tomorrow I'm going to make a cut a 3" hole in a piece of wood, and then place that directly below my plexiglass.  This will give the laminate/trim bit a nice area to ride on and make a perfect 3" hole.

Anybody have any other ideas for what I'm doing?  I'm pretty sure my idea will work OK, but I'm always open to other suggestions.

[Sasquatch!]

Today I bought a 3" hole cutter bit ($30 !!!  Home Depot said I could return it if "it doesn't work" even after I use it, heh)...

Rage against the Home Depot corporate machine.

[Nannuu]

Make sure you actually want it to be 3".  The largest part of the trackball is 3" but the top where you are drilling may only be 2 7/8 or less?  Anyway, my point is measure one more time to be sure  

[sofakng]

Well, I bought the 3" hole cutter already...  From what I've read though, I thought you're supposed to cut a 3" hole and not a 2 7/8" or whatever...

[chrisindfw]

Heres what I did...

Took a small piece of wood. About 1x4" or so.. Drilled a hole at one end, and screwed a screw all the way through the wood so the point is poking out 1 1/2" from the hole.

Drill your center hole for the trackball.

Put a bolt through the hole in the plexi and throught the wood..

Rotate the wood. It slowly cuts a very clean hole. It takes about 5 minutes of turning. About half way through i moved it to the other side of the plexi. I make the hole slightly smaller and then made it bigger with a dremmel so I have a tight fitting.

Just my ghetto way of doing it without getting a router and such.

[Kremmit]

Heres what I did...

Took a small piece of wood. About 1x4" or so.. Drilled a hole at one end, and screwed a screw all the way through the wood so the point is poking out 1 1/2" from the hole.

Drill your center hole for the trackball.

Put a bolt through the hole in the plexi and throught the wood..

Rotate the wood. It slowly cuts a very clean hole. It takes about 5 minutes of turning. About half way through i moved it to the other side of the plexi. I make the hole slightly smaller and then made it bigger with a dremmel so I have a tight fitting.

Just my ghetto way of doing it without getting a router and such.

Sweet idea!

[ThePaul]

Can't use the trackball mounting plate as a guide for the flush trimb it eh? That's really a bummer... I hate when I think I have something figured out in my mind then find out it doesn't work that way... seems to happen all the time in this hobby LOL  

[pointdablame]

why wouldn't you be able to use the trackball plate as a guide? It would serve teh same purpose as a piece of wood with a 3" hole in it.  That is what I plan to do also.

[ThePaul]

I've read a few posts where people say the tb mounting plate is too thing to use as a guide.

[patrickl]

What I wonder most is the 3" size of the hole. I understand this was mentioned before, but I find it so hard to understand that could be the right sized hole for a 3" trackball.

Maybe off-topic, but on the mountingplate trimming issue; even if you can't use the mountingplate directly for trimming the plexi, you should still be able to use it to trim a hole in wood to use as a template.

[FractalWalk]

If you are using a trackball mounting plate, then you want your hole to match exactly to the plate. I would be wary of anything that didn't derive it's dimensions directly from the plate.

In other words, I wouldn't use a hole saw. How can you tell if it is the exact same size and cut exactly in the middle of your plate?

[Pixelhugger]

In other words, I wouldn't use a hole saw. How can you tell if it is the exact same size and cut exactly in the middle of your plate?

....by clamping the plexi beneath the wood and cutting the hole thru the existing one. Assuming the existing hole lines up with the plate.

Or.... cut a smaller hole the same way. Then flip it over and flush trim it out.

The 3" hole saw works well. It's how I made mine. After cutting it I HIGHLY recommend bull nosing the edge of the plexi (if it's 1/4" stock) and polishing the bejeezus out of it. Here's a pic of mine. The image doesn't do it justice tho. It shines like glass. Oh, BTW the hole saw does cut a hole larger than the lip of the trackball.... but the mounting plate covers the gap and actually looks pretty cool.

Only regret is that I did this before Happs "invisible" mounting bracket was available. DOH!!

[Kremmit]

Pixel-

How does one "Bull Nose" plexi?  It looks really good!

[Pixelhugger]

With a router and a bullnosing or "round over" bit like this

http://woodworker.com/cgi-bin/FULLPRES.exe?PARTNUM=110-129

Available at any woodworking or decent hardware store. The trick is the polishing. Use a plastic polishing compound (a gritty brick of solid wax like material - around $5) and a polishing wheel (cloth wheel on a spindle - few bucks as well) in your drill or Dremel. You want a smooth (although frosted looking edge) prior to polishing. I smoothed the edge with 220 followed by 400 grit sandpaper before polishing.

So you:

Cut hole

Bullnose or round it off with a router using the matching hole in the wood below as a template for the router bit's bearing.

Sand it smooth with fine grit paper, taking care not to change the bevel of the edge

Polish with a cloth wheel in a drill or Dremel using polishing compound going lightly and carefully.

BLING... glass like shine appears out of the frosty edge.

This is always the most impressive thing about my CP when people first see it.

Here's a closer close up. Still doesn't do the edge justice....  

[Nannuu]

One of mine was similar to Pixel's.  This a a 2 1/4" with Ultimarcs mounting plate and 1/8" plexi.  I cut the hole smaller than 2 1/4"  and wish I'd gone smaller even.  The hole sets between the mounting plate and the trackball lip.  Rather than a bullnose I used a 45 chamfer bit and followed the same procedure as above to shine it up.

This is why I brought up the smaller diameter hole  

[Pixelhugger]

Nicely done Nannuu! That looks fantastic.

[FractalWalk]

....by clamping the plexi beneath the wood and cutting the hole thru the existing one. Assuming the existing hole lines up with the plate.

If I recall correctly, the problem is that sofakng has already cut and routed his wood and now he is trying to cut the plexi after the fact to match the CP.  This probably means that the exisitng "hole" is a cut out square for the mounting plate.

I don't believe a hole saw will help in this particular instance.



Or.... cut a smaller hole the same way. Then flip it over and flush trim it out.

For everything but the trackball hole, you can use a trim or template bit to follow your previous cuts. However, you can't trim out using the plate as a guide because it is too close to the CP (either the arbor misses the plate or the cutting edge misses the plexi).  If you space them apart far enough (e.g. stick some MDF in between) for the arbor to ride the plate while the bit cuts the plexi, then you run into problems lining up the plexi exactly with the CP.

I had the exact same problem and had to free hand a hole and sand it out to match the mounting plate.

[Pixelhugger]

he is trying to cut the plexi after the fact to match the CP.  This probably means that the exisitng "hole" is a cut out square for the mounting plate.

Yikes, hopefully that's not the case.

I don't know that all is lost if the hole in the wood has been cut away though.

What about trying this:

Secure the mounting plate to the particle board in it's final position.

Clamp the plexi to the board in it's final position

Use the hole saw to cut a hole in a separate thin sheet MDF.

Remove the resulting disc from the barrel of the saw carefully without enlarging the hole the drill portion of the saw left in the center of the disc.

With both the particle board and plastic still clamped together, turn the panel upside down so the plexi is on the bottom and you can access the mounting plate

Remove the saw barrel from the hole saw, so only the drill portion remains.

Center the MDF disc in the hole of the mounting plate. You'll probably have 1/8" or so around it.

Hold the disc CAREFULLY and firmly in place and place the drill back through the hole it originally left in the disc.  Remember... the saw barrel is OFF the drill and arbor at this point

Drill through the plastic carefully so you leave a perfect hole taking care not to enlarge it or allow for slop.

Unclamp the plastic from the particle board.

Replace the saw barrel onto it's arbor.

Feed the drill back into the small center hole you just made.

Drill the 3" hole using the small hole as a guide.

I imagine it will align about as accurately as you aligned the disc within the hole of the plate.

Or maybe I'm just talkin crazy talk.

To bullnose the plexi you would simply cut another 3" hole in a scrap piece of wood, align it with the plexi and clamp them together. Then use the hole in the wood as a guide for the router bearing.

[patrickl]

Or.... cut a smaller hole the same way. Then flip it over and flush trim it out.

For everything but the trackball hole, you can use a trim or template bit to follow your previous cuts. However, you can't trim out using the plate as a guide because it is too close to the CP (either the arbor misses the plate or the cutting edge misses the plexi).

You can buy trim or template bits where the bearing is much closer to the blade than the bits you have. Mine have no spacing between them at all.

You can also use the mounting plate to create a proper sized hole in a piece of wood. There must be a way to make sure you line up that hole correctly.

If all else fails you could at least take a CP sized piece of wood and make a copy of the main CP (all the button holes and mounting plate position). Use the mounting plate on that copy to create a 3" hole and then use this copy CP as a base for routing out the trackball hole in the plexi.

I wonder what sofakng's situation is though. Is there even a mounting plate? Didn't he explain in another thread he drilled a 3" hole in the CP wood?

[Nannuu]

Nicely done Nannuu! That looks fantastic.

I forgot to mention that I did mine this way after seeing Pixel's phenomenal looking trackball.  
You can learn cool things on the board!

[sofakng]

Ok, here's what I did for those that are curious...

First I cut a football shape out of my MDF for the trackball itself.  Next I drilled the holes for the trackball mounting plate and routed a small groove on the top so it would sit flush.

As for the plexiglass, first I cut a little wood template to fit onto the mounting plate.  I used a 3" hole cutting bit and a jigsaw (the jigsaw was only used to make the template square).  After that I attached my wood template onto the mounting plate (this gave me a circle for the router to ride).  Finally, I used my laminate/trim bit through the plexiglass and had it ride my wood template to cut a 3" hole.

It cut the 3" hole PERFECTLY.... but there was other problems....

Problem 1) I made two small "dings" (not cracks or scratches, but a little chunk of the plexiglass got removed..).  It's definitely visible, but not worth re-doing the entire plexiglass piece over with.  Maybe I'll re-do it down the road.

Question--  Do they make any plexiglass repair glue or anything?  I'm thinking something that would fill the dinged area...

Problem 2) The 3" hole cutting bit was bigger than the trackball.  The 3" is actually the size of the trackball plus the little black area bordering it (check the pictures above and you can see it there as well).   There's not much I can do about this, but again it's not a huge issue.  It would have been nice for *only* the trackball to be visible, but  

Let me know if anybody wants me to post pictures.  If so I'll post some later tonight.

[foomench]

The trick is the polishing. Use a plastic polishing compound (a gritty brick of solid wax like material - around $5) and a polishing wheel (cloth wheel on a spindle - few bucks as well) in your drill or Dremel.

Where do you get this polishing compound? Is this something I'd find at <insert favorite home improvement store here> or is this a more specialized item? What about something like this Dremel stuff (http://www.dremel.com/productdisplay/display.asp?sku=421&color=cc9900)?

I have a cloth polishing wheel for my Dremel. I also found this http://www.dremel.com/productdisplay/display.asp?sku=520&color=cc9900 which is for hard plastics. Does anyone think this might work, or is there too much risk in chipping?

-foomench

[pointdablame]

I'd also love to know about that plasctic polishing compound.  Is it a specific name, or are there different varieties of it?  Will it work on painted plastic too?  I'd like to polish up my newly painted xbox case, but have no idea what to use.

Sorry to derail the thread slightly.

[Nannuu]

This is the polishing compound I use with my dremel for plastic:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=9737

This is the dremel bit I picked up as well:
http://www.widgetsupply.com/page/WS/PROD/dremel-router-bit/D-AD09

[Pixelhugger]

What about something like this Dremel stuff (http://www.dremel.com/productdisplay/display.asp?sku=421&color=cc9900)?

That looks like it would work.

I also found this http://www.dremel.com/productdisplay/display.asp?sku=520&color=cc9900 which is for hard plastics. Does anyone think this might work, or is there too much risk in chipping?

I would stay away from a "solid" polishing wheel for plastic. It's not so much a risk of chipping but a risk of "warbling" or creating smooth divets in the plastic (which I even managed to do with a CLOTH wheel around a chipped button hole I was trying to polish back to normal. Granted I was a bit heavy handed and persistent, but if it can happen with cloth, I imagine it's far more likely with a solid polisher.

I'll see if I can find the name of the stuff I used. I got it at a local plastics store. I'm sure it's available online as well.

I don't think it would work on painted plastic... it removes too much. Maybe a mild car wax?

[pointdablame]

Yeah, I was going to try either a car wax or rubbing compound.  I have some tape designs on the case and I'd like to get rid of them.. so much for "no mark, less sticky" masking tape    If not... I guess I'll be sanding and painting again  

[sofakng]

So... umm... any suggestions for my problems mentioned a little ways up?

I've spent waaaay more than I planned to, so I'll probably not buy any new bits or anything, UNLESS you guys highly suggest I do it.

Like usual, my concern is appearance and even though this is my first cab, I really want this to look nice.

Do you think it will look OK with an extra large hole like mine?

[ThePaul]

I ran into the same problem this past weekend. I have already cut my CP (button holes football shape etc..) and now came the time to cut the Lexan. Everything was simple until it came to the trackball. Like you guys my flush trim bit had a little gap between the bearing and the cutting blades.

I took two scrap pieces of lexan and clamped them down over the track ball mounting plate (which is bolted into its proper position on the CP). The extra thicknes of two pieces of lexan rather than one was enough to let the bearing ride the TB mounting plate as a template and cut the top piece of lexan perfectly. The middle piece did not cut smothly, it melted a bit since it was positioned where the gap fell in the router bit.

Now I had one scrap piece of lexan with a perfect 3" copy of my TB mounting plate hole and one piece that was kind of jacked up. I threw the jacked up piece away.

Now I clamped the scrap piece with the perfect hole and my non scrap good piece of lexan to the cp (order was MDF-ScrapLexanwith3"hole-Good Lexan with no 3" hole yet). After drilling a pilot hole for my router bit in the good piece of lexan. I now had enough surface for the bearing to ride (the TB moutning place and the scrap piece of lexan.

My TB hole came out perfectly. As sofaking found the black lip is exposed although it sits flush with the lexan. I could have used the spacer that came with my TB, but then the amount of exposed ball would be less. I think I like to expose maximum ball

[sofakng]

Well, it shouldn't look too bad.  At least the lip is black so it matches most cabinets

Another strange problem I had for some reason is that after cutting the trackball hole in my plexiglass, my trackball mounting plate had some plexiglass melted onto the inside of it.  It's quite sharp but only amount a centimeter wide.

It's very hard to explain... It's taking FOREVER to file off too.  It didn't permanently damage it, but I'm really not sure how it got there...

[ras2a]

What about something like this Dremel stuff (http://www.dremel.com/productdisplay/display.asp?sku=421&color=cc9900)?

That looks like it would work.

I also found this http://www.dremel.com/productdisplay/display.asp?sku=520&color=cc9900 which is for hard plastics. Does anyone think this might work, or is there too much risk in chipping?

cheers
I would stay away from a "solid" polishing wheel for plastic. It's not so much a risk of chipping but a risk of "warbling" or creating smooth divets in the plastic (which I even managed to do with a CLOTH wheel around a chipped button hole I was trying to polish back to normal. Granted I was a bit heavy handed and persistent, but if it can happen with cloth, I imagine it's far more likely with a solid polisher.

I'll see if I can find the name of the stuff I used. I got it at a local plastics store. I'm sure it's available online as well.

I don't think it would work on painted plastic... it removes too much. Maybe a mild car wax?

I'd like to 'bullnose' or smooth the trackball hole also but was gonna opt for sanding (very fine wet and dry...wet).  However after seeing Pixel's SUPERB effort I don't think my idea will work.  I dont have/cant afford at this stage a dremel.  Is there ANY other method I can use to get the trackball lip smooth (not frosted) and chamfered?

[Pixelhugger]

If you have a router you can chamfer or bullnose it. You don't need a dremel to polish it. If you have a drill... which you must... you can get a cloth polishing wheel for that and use it to polish.

[ras2a]

If you have a router you can chamfer or bullnose it. You don't need a dremel to polish it. If you have a drill... which you must... you can get a cloth polishing wheel for that and use it to polish.

That's great - thanks pixel

[nostrebor]

I also used a router to round over the edges on my plexi, but I flame polished mine. Basically it is round over edges, sand with 180 then 220 then 400, then with a VERY light touch and a few minutes of patience, melt the edge with a small butane torch. You get to magically watch the stuff go from frosted to clear in seconds

 WARNING/DISCLAIMER!  Practice on scrap first. This is an aquired taste, and takes some getting used to. If too much heat is added, the plexi will bubble and distort. On mine I just pass the flame quickly over the edge repeatedly, sneaking up on it so to speak, until it just starts to kick over. If you over-do it all is lost.

I'll try to get some pics and post later.

EDIT: pic added... ignore the white fuzz at the inside of the opening, its just rough edges from a temp cpo. this polished opening took approximately 15 seconds to flame

[ras2a]

If you have a router you can chamfer or bullnose it. You don't need a dremel to polish it. If you have a drill... which you must... you can get a cloth polishing wheel for that and use it to polish.

Just gotta find a polishing cloth wheel for plastic now!  Will have a mooch around

[Pixelhugger]

May not need to mooch much. Should be around $7 at the local hardware store.

[drunkatuw]

Definitely don't try to use the trackball mounting plate as a guide for a flush bit on a router...I made the mistake and had to buy a second mounting plate.  Even if the mounting plate is made out of metal, even an old router can rip right through it.  I ended up using my old (read ruined) mounting plate as a guide to create a new template.



And I think it turned out pretty well...

(The flash makes it look like it's not flush, but it's perfectly flush all the way around the trackball)

Edit: Spelling

[ras2a]

Hey drunk, that's brilliant...sorry about your first trackball plate.  I'll deffo not be using mine!

[ras2a]

Ok, I am getting pretty worried about cutting the trackball hole out of the lexan for my CP.  I've done a rough drawing of how I understand some of you (I think) have/intend to do it using your Trackball plate as a 'guide' >>>



The way I see it, if the router bit is tight within the router and a steady-hand used, then there can be no movement up and down and therefore no chance for the router bit to 'dig in' and ruin the trackball plate.  Does this approach look ok and is this the method used by some other people?  Of course I'll be clamping the lexan to the cp firmly so it cannot move!

One more question, do you guys sandwich your CP art in-between your lexan/plexi and CP so that you can cut holes through it at the same time as the lexan/plexi, or do you cut the holes out of it after with a scalpel/craft knife etc?

thanks a lot

EDIT: Just read those posts stating that this method can't be used due to the space between the bearing and the cutting blades on the bit.  I'll re-read through some of these posts!  DOH!

EDIT 2: Is the Trackball mounting plate hole exactly 3"?  If so I'll use a scrap piece of MDF and drill a 3" hole through it..then attach this piece to the plate and use the extra depth for the flush-trim bearing to ride along.  

[Dekelia]

Definitely don't try to use the trackball mounting plate as a guide for a flush bit on a router...I made the mistake and had to buy a second mounting plate.  Even if the mounting plate is made out of metal, even an old router can rip right through it.  I ended up using my old (read ruined) mounting plate as a guide to create a new template.

I wish this topic had come up prior to last weekend.  I was going to do the same thing with mine (trimming laminate though, not plexi).  I realised that with my trimming bit I couldn't use it for a guide.  I finally decided to take the chance and just be very careful with the router and just "feel" when the bit got the metal and glide around the inside.  

Well, mine didn't look quite as bad as your ruined plate but the same idea.  It was too late to replace mine (had already laminated it...to much work to go back now) and it doesn't look too bad (I'll probably be the only one that notices).

Once I realised I was hacking it up a bit (only in one place) I just used the router to get very close to the edge freehand and used my dremel with a grinding bit (which does stop when it hits the metal) to make the laminate flush.

[ras2a]

May not need to mooch much. Should be around $7 at the local hardware store.

Still can't find one of these polishing wheels.  What are they made from Pix?  is it a soft material.  I've seen something called a ''flap whee', but this looks to have abrasive 'flaps' protruding from it.  I would have thought the polishing wheel would have been smoother.  Unless it's just a case of getting the correct grade?

just had another thought, would using very fine wire-wool be ok for polishing the chamfered edge?  maybe in combination with a plastic polishing compound?