Acrylic Starter settings and glue source?

[Mike Audleman]

Looking at getting some acrylic sheets from Home depot this weekend so I can fab up a meter box for my china 50.

I have never done acrylic. So I don't have a clue for a starting point. Anyone have suggestions on where to start for power/speed to produce clean cuts? I will worry about figuring out engraving later. Right now, I just need a box to mount the mA meter in.

Also, anyone know a local store to acquire the welding cement for gluing the panels together that might be here in Milwaukee? Would like to run in and buy a can rather than ordering online and waiting. Even just a small tube to get this project done would be sufficient. I can worry about a larger supply via online later. Home Depot, though they sell acrylic sheets, don't seem to have a clue about acrylic glue (cement, chemical welding).



As a side note, can you actually gut polycarbonate? My SIL gave me some end-cuts from where he used to work. All it does is make fire and smoke. Very little penetration. The protective sheet says Tuffak. I think its about 1/4" thick and was used for windows on food processing equipment. Stuff is tough as nails. Is this stuff beyond my laser's ability?

[Tony Lenkic]

Your best source would be local sign companies. Often they will have off cuts that will go in dumpsters.
They may have acrylic weld glue as well.

Otherwise, contact N. Glantz (sign supply company)...........7000 W Marcia Rd, Milwaukee, WI 53223, USA

[Kev Williams]

50w glass laser, I assume 1/8" thick plex? Find what power setting entered hits 26mA on your meter, then set the speed at 15mm/sec. That should be close. If it doesn't get thru in one pass, deduct speed in 3mm increments...

As for gluing acrylic together, if you don't need immediate bonding, go to Lowes or HD and pick up some of this-
go2.jpg

it bonds great and bubble-free, but there's a waiting time-

Otherwise, you need basic acrylic cement, and best advice I have is to google "acrylic plastic supplier [your city]" and see what comes up. Anyone selling anything to do with plastics should have it-

and don't mess with polycarbonates, it doesn't like lasers...

[Mike Audleman]

Your best source would be local sign companies. Often they will have off cuts that will go in dumpsters.
They may have acrylic weld glue as well.

Otherwise, contact N. Glantz (sign supply company)...........7000 W Marcia Rd, Milwaukee, WI 53223, USA

Emailed them. Had already emailed Midland plastics as they are on the way home from work. I also emailed SignsNow as they aren't too far from work here (so I can pop out and buy if they got it).

50w glass laser, I assume 1/8" thick plex? Find what power setting entered hits 26mA on your meter, then set the speed at 15mm/sec. That should be close. If it doesn't get thru in one pass, deduct speed in 3mm increments...

As for gluing acrylic together, if you don't need immediate bonding, go to Lowes or HD and pick up some of this-
go2.jpg

it bonds great and bubble-free, but there's a waiting time-

Otherwise, you need basic acrylic cement, and best advice I have is to google "acrylic plastic supplier [your city]" and see what comes up. Anyone selling anything to do with plastics should have it-

and don't mess with polycarbonates, it doesn't like lasers...

Rofl! The mA meter is exactly what I want to mount

All I am trying to start out making is a box for the mA meter and some extra switches that will mount on the top right area of the laser behind the emergency button.

And, if that goes well, other projects to follow. Was hoping for a small tube locally at least to get started.

Found ePlastics online. $31 for a pint of #4 and an applicator. Seems a bit high. Especially since I can get the same thing off ebay for about $14 with an extra needle. Problem with either is I won't see them until end of next week.

Thinking the Loktite glue (assume its glorified super glue) may get me a box this weekend. I am probably gonna paint the outside a cream color to sorta match the rest of the laser. So pretty isn't a requirement. Staying together is.

So polycarbonates aren't an option. Bummer. He brought me a stack of pieces that are about 18" long by 10" wide. Probably 15 to 20 pieces. I can always saw and mill them with the router I suppose. But, yea, tried various guesses as to power and speed. Just made flames and black marks. Nothing usable (hoped to use it for the meter box).

[Bert Kemp]

1/8 BB makes a great box for the amp meter and just white glue. but if you want extruded acrylic 1/8 from HD like Kev said .

[Mike Audleman]

1/8 BB makes a great box for the amp meter and just white glue. but if you want extruded acrylic 1/8 from HD like Kev said .

I will be running 120v up as well as 12v and 5v dc (the extra switches mentioned) and the lead from the tube to the meter. I don't think wood would be an appropriate material for housing 120vac. I have sheets of 3mm BB as well as HDF. Most likely will use that as test pieces for fitting before cutting the acrylic.

[Neville Stewart]

Weld-On #4, its not an adhesive, its " melts" the acrylic momentarily, mixes together then resets. Essentially becoming one piece.

[Mike Audleman]

Weld-On #4, its not an adhesive, its " melts" the acrylic momentarily, mixes together then resets. Essentially becoming one piece.

I know its not an adhesive. Its actually a chemical welder. However, talk to someone in an orange vest at HD about a chemical welder and see how far the conversation gets you

[Bill George]

You don't have room on the laser panel to just mount the meter? You should be able to borrow a hole saw the right size from your electrician or plumber neighbor. Or just cut a square hole and use your laser to cut out for the meter and switches as needed in your acrylic sheet panel face.

[Mike Audleman]

You don't have room on the laser panel to just mount the meter? You should be able to borrow a hole saw the right size from your electrician or plumber neighbor. Or just cut a square hole and use your laser to cut out for the meter and switches as needed in your acrylic sheet panel face.

I have hole saws. And greenlee punches too.

However the panel I wish to mount it is not sloped very much so my viewing angle on the meter would make it all but impossible to read. And mounting it in the front would also make it very difficult to read being too low. My laser is sitting on a stand (where my radial arm saw used to). So the top is at about my chest level.

I don't think it will fit in the front anyway with the control panel, then below that the USB and the power switches. The meter I will use is an old one from my parts bin from old transmitter equipment. A Burlington ca. 1945 0-50ma meter. I cleaned the pin bearings and tested it against a bench supply, resistor and two digital ammeters and its dead nuts on at 10, 20 and 30ma which is the range I care about. I chose it because its a nice big 3" meter which means easier to read scale. It, unfortunately, is not a shallow meter. I would have to look but I believe its a good 4" deep to the pins.

Here is the machine:

This is the closest photo I can find of mine. My control panel isn't quite the same, its not recessed as shown. And I am pretty sure its farther forward as well as there is more space between mine and the kill button.

I can't mount it to either end as other things sit there and it wouldn't be easy to get in behind the machine if I did.

I removed the yellow stickers (caution) using a heat gun and had planned to place the box there behind the kill switch with the meter facing forward closer to eye level.

So, my solution was to build a box that would sit on the slightly sloped area on the top behind the emergency cutoff. I was going to angle the front slightly but that may not be practical with acrylic. Anyway, that would place the meter at a comfortable viewing height and angle.

[Dave Sheldrake]

16mA max on that tube or it's as good as dead

[Clark Pace]

I think someone should mention when joining lasered pieces on a lasered edge may cause crazing (mini cracks). Also a weeker bond. To minimize crazing use cast acrylic if you must glue. Sorry for the typos. I stink at texting

[Kev Williams]

Sorry, I'm not up on max mA ratings related to tube power--

so then try 70% power, that's where mine hits 27mA, which is the borderline for an 80 tube (I think)

And that Loctite isn't anything like superglue at all- it's the consistency of Blue Agave sweetener (like honey only not as thick, and if you haven't tried, it, get some, it's about twice as sweet as sugar with less calories and carbs!)--

It's more like thinned out clear silicone caulking, even has a faint silicone smell- it's crystal clear and remains flexible when dried, unlike superglues..

Honest, I don't sell the stuff, it just works great---

[Lee DeRaud]

...but if you want extruded acrylic 1/8 from HD like Kev said .

Does your HD actually sell 1/8" acrylic? Mine has 1/4" (nominal, actually 0.22"), but all the thinner stuff is 3/32" (0.092").
That's been true since I bought the laser in '05.

[John Lifer]

Just don't buy any Dap rapidfuse. Supposedly works on acrylic but took two days to dry and no strength at all.
Lowe's down here has several thickness of acrylic. I've some solvent off eBay seller was good and it works.