Do you have a pin table? How tall are the pins?

[Daniel Reetz]

I'm considering either making or buying a pin table. What I can't tell exactly from any of the pin tables I can find on the market is: how tall are the pins?

A little background:

On my Epilog Zing, I usually support workpieces with four 4" tall aluminum blocks. Using these blocks, there is absolutely no back-burining.

This method has worked well enough, but I'm starting to see the limitations as I get much more efficient with programming artwork. Now, most of the time there is no material left between my lasered pieces, and so I can't count on the material itself to provide any support. Seems to me that a pin table is an ideal solution. Any thoughts or suggestions here?

[Martin Boekers]

An idea I have been toying with is get some "L" aluminum channel, cut it to different sizes and add a couple magnets to the bottom.

http://www.brunnerent.com/Tools/Portfolio/frontend/item.asp?type=5&size=0&lngDisplay=0&jPageNumber=4&strMetaTag=

These would be easy to set up as well as store. They could be staggered, as well as set at angles. Very versitile.

And Cheap!:D

I haven't had a chance to get some in to try yet, but I thought I'd toss it out there in case it may fit your needs. If airflow becomes an issue I could drill holes through it to help promote the air flow.


Marty

[Daniel Reetz]

That's an interesting idea. I have a few of my own, as well. But I'm still curious what people think the pin depth should be. With a 2"FL lens and a 30W tube, I wonder what the minimum depth between the workpiece and the bed should be to prevent the back of the workpiece from being marred by the beam.

[Dan Hintz]

Depends upon your power level and the material you're cutting. 1" would probably be safe for a lot of materials, like wood, but to be on the safe side I would go with 1.5-2". Experiment and see...

[Daniel Reetz]

I would go with 1.5-2". Experiment and see...

Looks like that's what I'll be doing. Acrylic is my target material, so I'll err on the tall side of things.

[donald bugansky]

The vector pin table I purchased has 2 5/8" pins.

If you need photo to assist you, let me know and I'll post.

[Joe Peacock]

I have my acrylic up off the table 1". Are you all saying here that having the work higher than that will eliminate the "smoke damage I experience if I remove the protective covering from the underside of the acrylic? If I could remove just one side of the protective covering it sure would speed things up with the things I am producing. Being able to remove the protective covering from both sides and somehow not end up with smoke stains would be a huge thing for me.
Joe

[donald bugansky]

Joe,

I'm no expert by a long shot as I'm just learning. I cut a ton of acrylic this winter as I made about 200 ornaments.

I was having all kinds of smoke residue (don't clean it with brake fluid - that's another whole story) and purchased some pin tables.

It worked for me as the residue is no longer there.

[Dan Hintz]

Joe,

Height of the pins doesn't really have an effect on smoke damage, just on flashback.

[Joe Peacock]

Joe,

I'm no expert by a long shot as I'm just learning. I cut a ton of acrylic this winter as I made about 200 ornaments.

I was having all kinds of smoke residue (don't clean it with brake fluid - that's another whole story) and purchased some pin tables.

It worked for me as the residue is no longer there.
Donald,
Are you saying that the pin table cured your smoke damage problem? How high are the pins above the table?
Joe

[donald bugansky]

Joe,

The pins helped minimize the smoke damage as the pins allow the smoke to be drawn immediately into the exhaust. When I just used the honeycomb vector table, I think the smoke was trapped just long enough to leave the residue. Now it's rare that I get noticeable smoke damage.

Another issue was that I was using inexpensive acrylic from the big box stores and it only had the plastic covering on both sides which required you to remove it prior to cutting as it would melt if you left it on.

So in the end, I believe if you use the acrylic with the paper coating (remove it from the top but leave the bottom on) it is a major improvement and may mitigate the need for a pin table.

[Dan Hintz]

Donald,

If you remove the plastic, replace it with vinyl transfer tape... no more smoke damage.

[donald bugansky]

I forgot to mention that. In the end, it's far better (for me at least) to just buy the better acrylic versus pulling off plastic covering, then masking with tape.

The masking (bought at LaserBits so I'm not sure if it was vinyl) worked but when using larger acrylic sheets 24x18, I had issues with getting the air bubbles out of the masking, plus fighting with the roll as it took multiple rows of masking to cover the sheet and then cutting a clean edge each time I ran a row of masking....blah blah blah. What was supposed to be fun turned into a pain in the rear end. It only took about 5 sheets of the cheaper acrylic and issues above to just move to better acrylic.

After a frustrating weekend, I just bought the better acrylic, pulled the top layer off and had some fun.

Much easier and a whole lot more fun!

[Daniel Reetz]

The vector pin table I purchased has 2 5/8" pins.

If you need photo to assist you, let me know and I'll post.

THANK YOU!

I ended up finding a cache of 3.75" pins, so at least I'll know that they're over-spec. If you find the time, a picture would be very helpful, thanks!

[Michael Kowalczyk]

The vector pin table I purchased has 2 5/8" pins.

If you need photo to assist you, let me know and I'll post.

Hey Bugs,
Where did you get the pin table? from Trotec? or other?
Please post a pic :D


Daniel, Did you have your cache of 3.75" pins just hanging around or where can one get them now may be a better question?

I've been wanting to make one out of 1/2" solid surface for the base and drill the grid of holes on my CNC. If we can find some good (inexpensive) pins this could end up as something good for all.

Thanks and ...

[Daniel Reetz]

Daniel, Did you have your cache of 3.75" pins just hanging around or where can one get them now may be a better question?


Sorry, Michael, I bought them at a local surplus place and I bought all of them -- 20 in total.

I'm starting to think that stainless steel screws might be a good alternative. In fact, I am thinking about fabricating the base from acrylic (covered in aluminum foil tape to prevent it from melting over time) with screws embedded in it. I'll make 2 12x12" tables to fill the bed of my laser.

If I can get a decent design going this way, I'll surely share back the plans and art here.

[Dean Carpenter]

Hi To all,

To the best of my knowledge we were the originators of the pin table way back in 1998. You can see details at this link: laserite.com/co2-speedy-300-pin-table.html
Feel free to copy it; everyone else has!

The length of the pins depends on how stable and accuracte the table is made, the thickness (weight) of your material + the focal length of your lens and the power of your laser. Longer pins wobble more, especially if the material is light but longer pins are better to prevent small cut parts from accidentally being scored over after they have been cut-out from the sheet and have fallen through.

Your pins need to be stainless steel and they must be CNC machined fior accuracy. Round then ends, don't make them to a point.

Our early day versions had tapered pins for greater stability but this adds more weight to the fixture.

regards

Dean

[Dan Hintz]

Your pins need to be stainless steel and they must be CNC machined fior accuracy. Round then ends, don't make them to a point.
So my inverted golf tees won't work? ;)

[Daniel Reetz]

Dean, thanks for dropping in. I checked out your work and your site -- very impressive.

I came up with something that I'll share here soon. It's a simple, cheap, laser-able pin table that worked really well for me and my small-time stuff.

[Tom Bull]

You can buy stainless steel pins from McMaster-Carr with a tolerance of .01 inch 2x1/8 inch about 50 cents ea. Would that be suitable?

[Vaughan Raymond]

Wouldn't finishing nails work for pins?

[Michael Hunter]

Only two important requirements for the pins -

1 The fit nicely into the holes - neither jamming nor wobbling.
2 They are all the same length (to within about 10 thou if possible)

So nails should be OK. You can always use a file if the lengths are a bit off.
Because nails are pointy, you would need to be careful about scratching the underside of the workpiece.

Precision pins (dowels) even better.
The dowels I have seen normally have one flat end and the other very slightly rounded - perfect for the job.

[Dean Carpenter]

Sorry for not dropping in for a while; i've been away

The table must be stable and the pins fixed well. If they wobble the quality of your cut will suffer.

If the length of the pins vary then again, your material will wobble and you'll have defocus problems.

The pins must not be sharp. Otherwise your material will get scratched.

Ideally, the pins should be rounded on the ends to prevent scratching + as an added benefit this helps to bounce away any beam that passes through the material