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Jackie McGowan
02-16-2009, 12:57 PM
Hi,

I was wondering if there are any tricks you all use to align certain pain in the butt things. I have a plaque order (5 plaques -2 different sizes). I'll be lasering them one at a time as they are pretty large. My issue is I normally put something like this against the rulers but the rectangular plaques are rounded on the face and the back edge, so the edge is higher than my ruler and I can't but it. I thought of just lasering the image on a cardboard and then positioning best I can using that but the design has a line border and if it's off it will be very noticable. I wish my laserbed had a grid on it, that would help. Is there anyway to do that to the laserbed? Any thoughts, tricks experiences?? Can you tell I'm a little nervous!! not only about that but I'll be using the laser foil for the first time (that I'll practice on something else first).

Allan Wright
02-16-2009, 1:05 PM
I will usually make a positioning jig for cutting irregular things. I don't do a lot of engraving, but the one thing I engraved that couldn't be put up against the rulers I made a jig. I used some scrap plywood (that aligned to the rulers) and glued some blocks to it located in such a way that the engraved object couldn't move. I don't have a picture of the jig, but here's the object I was engraving:

http://www.wrightbrothersrc.com/img/engrave/nash1.png

Hope that helps.

Allan Wright

Albert Nix
02-16-2009, 1:21 PM
A lot of time I just measure them up, draw them on the table top, change them to a fine red line. lay a piece of white poster board down the turn the power down and lightly burn the patterns on the board then just lay them in place and go to town. Cheap template.

Hilton Lister
02-16-2009, 1:44 PM
Me Too,
I also place cardboard on the bed and laser the outline. Quick And Cheap

Martin Boekers
02-16-2009, 1:47 PM
Hi Jackie,

Here are some photos of a jig I made, I use this one daily!

I started with a thick piece of plywood, then with wood sheets from laserbits cut the outside rails. I then attached them to the plywood base.

Remember you have to subtract approx .125 inch from the top and ad .125 inch to the side as that takes into consideration the size of the edge pieces. I usually set this up in the file.

Out of a thicker sheet from laserbits I made the wedge for the crystal base and the back static piece (this holds the base square and firm while I position the wedge to level the top of the base.) The static piece is needed as when I would level it without this piece the base would shift out of the engraving area.

If anyone has a better way to do these bases please share them!:p

The bases usually aren't square so it take a bit of efferort to make them work.


Hope this helps!


Marty

Jackie McGowan
02-16-2009, 1:49 PM
Thanks Everyone, I thought that would be the way to go but wasn't sure :)

Mike Chance in Iowa
02-16-2009, 3:19 PM
I took a different route. I have blocks of - " thick wood that are the same width as the ruler guides. I simply stack the blocks of wood on top of the ruler guides until I reach the height of the item I'm trying to align.

Mike Null
02-16-2009, 4:22 PM
I usually use plywood or 2x4's against the rulers then measure accordingly.

Sometimes I use a draftsmans triangle to line up items, particualarly acrylics which aren't always uniform.

George D Gabert
02-16-2009, 4:30 PM
for our milling machines we use several pieces of aluminum square tube of differing square dimes. like 1/2" and 1" that you can get from lowes or HD. Use these against the rulers and subtract the square dimes from your corel home to your plaque.

GDG

Dan Hintz
02-16-2009, 5:46 PM
Jackie,

Pick up a length of 1" wide square aluminum stock and cut to table length. Set two pieces along the rulers but inside the table. Offset your design by 1" in the X and Y directions. The square stock should be high enough to push most substrates up against it. No welding, no fasteners or screws, etc.

Stephen Beckham
02-16-2009, 8:18 PM
Jackie,

Not sure if your laser gives you an X/Y readout of any sorts. If so, what I do is lay the odd or large object in the laser, get some good X/Y points of reference then use the guidelines to lay them out on the screen.

For instance, when I do raised panel doors that are too large and have to sit up on top of the rulers, I put a guideline across the top and bottom of corel where the top Y and the bottom Y are then repeat for my left and right X positions. Afterwards, I have a square on the screen that shows me exactly where my raised panel is located in the laser.

For the really strange ones, I recreate the shape of the item in a hairline then just use the laser pointer to trace the item in vector mode with the door open. When it's close, then what you put in the item on the screen lines up with the item on the deck.

art baylor
02-16-2009, 11:11 PM
Would it be difficult to do a Ceremark grid on the bed?

Art

Mike Null
02-17-2009, 7:45 AM
If you take Martin's idea and raise the tabs you can slide his jig against the rulers and still have the laser's 0-0 point.


Sorry forgot dwg.

Jackie McGowan
02-17-2009, 8:44 AM
Stephen,
The X/Y I can do, I just never have and forget that I can. Thanks for reminding me.


Mike,

I know what you mean with the tabs (like on the risers that came with your cutting grid) good idea!

Dave Yanke
02-17-2009, 9:13 AM
Another quick way I learned from Dave Stevens when I was at ULS in Arizona is to use tape.

If you have the outline of your plaque, us it as part of the design. Turn of all but the outline in the object manager.

I use very wide masking tape and place it down on the table in the general area where the plaque will go. Using the laser, cut a line in the tape and weed out where the plaque will go so all that is left is the outline.

Now simply place the plaque in the tape in the area you removed (the outline of the plaque) turn off the outline in the object manager, turn on the elements you want to engrave.

I am writing this while multi-tasking so it may not be as clear as it should be. It actually take more time to explain then do but it can make a nice down and dirty method to quicly do odd shaped items.

Dave Johnson29
02-17-2009, 11:28 AM
My issue is I normally put something like this against the rulers but the rectangular plaques are rounded on the face and the back edge, so the edge is higher than my ruler and I can't butt it.


Hi Jackie,

May be too little too late but here is what I have. The rulers are at the bottom for flat stuff, then I have spacers (nuts) to support 1-1/2" x 1/16" aluminum angle. The angle is on the spacers so I can get a good draft-through for smoke removal when doing flat stuff. The slots in the aluminum also allow good draft with taller stuff.

I machined up the angle a few months back and it all works well without the need for any adjusting or swapping things out. You can get a better look at the angle in this older posting.
http://www.sawmillcreek.org/showpost.php?p=950080&postcount=1

When the beam is focused on the bare table top, the bottom of my lens mount is about 1/4" above the top of the angle for clearance.

Richard Rumancik
02-17-2009, 11:36 AM
When I am in a hurry and there is only one item I often park a piece of plywood or MDF up to the rulers, plot the plaque or part outline, and set the plaque into place. Many of you seem to be doing something similar.

But when doing several items, and where I can't afford to have an error, I use a different approach. In that case I screw the MDF down to the table so it cannot move. (I drilled four holes into my aluminum table to accomodate screws.) Then I know that movement of the fixture is eliminated.

Then I plot the outline on the MDF from the file. I then attach "stops" right up to the line. They can be wood blocks or acrylic blocks. It can be handy to make them with slots if you want them to be adjustable. Three blocks are adequate (two on the long edge and one on the short edge.) I use a battery powered drill to make a few holes in the MDF for the stops and then screw them down with washers and wood screws.

If there is a chamfer or radius on the underside of the plaque, the block is thick enough so that is not an issue.

In some cases I apply another special block to force the plaque into the "corner" and keep it from moving outwards from the stops.

If I have to set up the same job again, I would not use the old lines. I would move the image on the screen and replot my outline again. If the MDF gets a few too many lines you can spray paint it and keep using it.

By moving the working area out from (0,0) to say (6,6) I find that I can see the work much better.

Brian Robison
02-17-2009, 1:57 PM
I made a fixture years ago out of 3/4" ply wood with 2 pieces of wood ( 1 x I think) sticking up about 1" on the top and left sides (0,0 corner). The plywood fits square in the corner. I made sure the wood was up just high enough to clear the rulers. No Math! I bet I've used it thousands of times.

Shaddy Dedmore
02-17-2009, 4:26 PM
If you take Martin's idea and raise the tabs you can slide his jig against the rulers and still have the laser's 0-0 point.

Do this, it's pretty easy really, and you don't have to make changes to your 0,0.

Take a 1/2 or 3/4" piece of ply or MDF then butt it up to where your rulers are, then take a thin piece of anything, even more ply would work, 1/8 or 1/4 then staple, nail, glue it to the edges over your rulers. up on it's edge would be best... so...

cut a rectangular piece of wood for a base, 1/2-3/4" that fits your table. then cut some thinner pieces like 1.5" x 12" x 1/4" change the 1.5" to the height needed to match the piece you're needing to position

Put large piece in place, snugged up to rulers, then put smaller pieces in place, on edge, up against the larger piece (covering up a little of the ruler) then affix it somehow, screw, glue, nail, staple.

there you have it.

Shaddy

Bill Cunningham
02-17-2009, 10:03 PM
Anything that will butt up against your rulers, but is still higher than your rulers will work.. Scrap wood/mdf, thicker plastic, ..etc..