# resufacing cnc router table



## signman1 (Mar 2, 2011)

I have a Gerber Dimension 200 & don't know how to resurface table. Any help would be greatly appreciated.


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## xplorx4 (Dec 1, 2008)

Greetings and welcome to the router forums, we are glad to have you join us.


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## jw2170 (Jan 24, 2008)

G’day 

Welcome to the router forum.


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## Cherryville Chuck (Sep 28, 2010)

I had a look at one on youtube and it appear5s to be a metal t-slot table. If it is best to take it to a machine shop and ask there.


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## Arcticfox46 (Jul 19, 2007)

signman1 said:


> I have a Gerber Dimension 200 & don't know how to resurface table. Any help would be greatly appreciated.


If it is aluminum -- you could mount a 3/8 of 1/2 3 or 4 flute carbide end mill in the spindle. Touch off and zero the tool to the table top. 

Write a simple program to zig zag across the table and cut it at Z-.005 or so until the entire table is flat.

That is how I did mine. No regrets.


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## Trevor Walsh (Jan 12, 2011)

I don't know about other manufacturers, but the company (Techno CNC) that built ours does not suggest levelling the extruded surface. From a metallurgy point of view that can do more harm than good. 

Your best bet is to use some contact cement to adhere strips of 1/4-1/2 mdf in a way as to not interfere with the t slots. Then use a large zig zag pattern and a surfacing bit to flatten to the machine. 

I do the same thing with the stock hard rubber strips that are on there now, and plan to replace them when worn with 1/4 MDF.


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## Arcticfox46 (Jul 19, 2007)

Trevor Walsh said:


> I don't know about other manufacturers, but the company (Techno CNC) that built ours does not suggest levelling the extruded surface. From a metallurgy point of view that can do more harm than good.
> 
> Your best bet is to use some contact cement to adhere strips of 1/4-1/2 mdf in a way as to not interfere with the t slots. Then use a large zig zag pattern and a surfacing bit to flatten to the machine.
> 
> I do the same thing with the stock hard rubber strips that are on there now, and plan to replace them when worn with 1/4 MDF.


What harm does it do?


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## Trevor Walsh (Jan 12, 2011)

Excellent question, from working with solid wood we know or may have experienced wood that wasn't quite dry in the middle, when you cut it or let it sit, this moisture difference becomes apparent by resulting in warped stock...

A lot of metals have similar stressed caused by work hardening Cold Rolled Steel for example has more stress than Hot Rolled, nicer finish, but the cold rolling work hardens the exterior layer of steel and can cause warping when only some of those layers are removed.

Aluminum extrusions may not suffer from the same drastic stresses as CRS does, but considering the possibility, and the fact that the extrusion is only so thick, what happens after it gets flattened three, four times? Now you might be looking at a buying a new table rather than a sheet of mdf. 

And if that doesn't do it for you, I'd think the small feeds and passes needed for cutting aluminum, and the cost of cutters that it's way cheaper and faster to do an mdf top. 

I hope I make a little more sense now.


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## Arcticfox46 (Jul 19, 2007)

I am a manufacturing engineer with over 30 years experience cutting metal, including aluminum. I cut metal all day, every day.

I have in fact cut the machine bed of my own machine about 2-3 years ago.

Yeah there are stresses in metals, but it would be totally insignificant in this case, whereas the material removed would be maybe .010-.020

Cutting the bed with the machine will ensure that the bed is parallel and flat with respect to the "X" and the "Y" axis.

Of course, I can understand the inhibition in cutting the machine bed. It is "sort of" an unusual and somewhat scary thing to do. It kinda messes up that "new" look.



Actually before cutting the table top:

Is there a way to shim and adjust the table with respect to the "X-Y" axis with an indicator mounted in the spindle? 
A decent result could possibly be had in that.

Have you contacted the manufacturer about the steps needed to get the bed flat and parallel?


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## Trevor Walsh (Jan 12, 2011)

I think that after use re-flattening the metal top just eats away at your table. I'd rather get a few flattenings from 1/4" mdf and replace that periodically.


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## BOOMER52 (Jun 4, 2011)

I'm certainly no expert but I did build my own CNC router. One of the setup adjustments was 'tramming the head' or insuring the router was plumb, level, & square to the table. However that may or may not completely solve the issue... so I and almost all others I've communicated with in my CNC router community use a sacrificial swarf board... typically MDF... that we machine to that plumb, level, & squareness we are looking for. 

I took a gander at the particular machine you own and the gantry clearance seems to be at a premium... so something like 1/4" MDF might be best for this approach. I have a 3/4" MDF swarf board that I resurface on an as needed basis... especially if I do a lot of profile or through cutting. I'l be able to do that 3-4 more times before I need to replace it.

BOOMER52


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## acryldesign (Jun 7, 2011)

I currently own a gerber dimension 200 & 2 saber 408 s with vac tables manufactured by the same company. I purchased the dimension 200 15 years ago . In the beginning t slots were used for clamping which they still are & vac tables came into being. With that MDF was found to act as a sacrifice sheet that you could mill down to keep the integrity of the x y plane to the traveling router head. My suggestion is do not change the integrity of your machine by milling the extruded bed table. MDF was suggested earlier with contact cement . The dimension 200 comes with a milling program in router utilities that is to mill the table for it is expected to be done. One further suggestion is to use Sintra ( foamed pvc sheet.25 thickness ) other brand names will work . Mdf is more used for the vac tables because it is porous. Then mill the surface with the program supplied. Also I use aggressive double sided tapes to adhere the sintra to the bed around the perimeter of the slats for we go through the sintra slats periodically and it makes them easier to remove


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## Onfilm1 (Oct 4, 2015)

The correct way to "level" the surface of a Gerber Dimension 200 (or 800) CNC Router table is this:

1. Cut 1/4" thick strips of SENTRA to fit each of the tables aluminum "strips".

2. Remove whatever material that is currently attached to each of the tables aluminum "strips".

3. Thoroughly clean each aluminum "strip", removing all traces of tape, glue, etc..

4. Carefully cover each aluminum "strip", one at a time, with heavy-duty Double-Faced Tape.

5. Carefully attach each piece of 1/4" SENTRA to each aluminum "strip", and firmly press down to insure a very tight bond to the tape,

6. Once you have all 1/4" thick SENTRA pieces firmly attached the the table, press it all down very firmly again.

7. Open your Gerber GSP software program, and open your file manager. 

8. Look for the Table Surfacing file. It looks like a "square" with several lines running through it, left to right, and up and down.

9. Load this file into you ArtPath screen, and make sure you have the correct sized table selected (Dimension 200).

10. Using your Router's Control Unit, move the Router head into the correct position for cutting, which should be the at the front right corner of your Router Table.

11. Make sure you have the proper Router Bit installed in the chick, and make sure you select the correct Router Bit size in the ArtPath program.

12. At this time, you want to "Zero" your Router Bit to the table, usually done with a 3" x 5" piece of 3/16" Plexiglass scrap. Save this. It's your new Depth Guide.

13. Raise the Router Bit by turning the knob on the top of the Router Motor, and put the Depth Guide onto the table surface, across at least two parallel "Strips".

14. Turn the Router Motor height adjustment knob until the Router Bit just meets the surface of the Depth Guide. 

15. Slide the Depth Guide around, raise or lower the Router Bit height until you achieve a "no play in it" condition. You Must be able to remove the Depth Guide.

16. Press the INIT button on the Router's Control Unit.

17. In ArtPath, select the proper file, and send it to your Router's Computer.

18. Wait for the "BEEP". 

19. Make sure everything is cleared from the table surface, and all safety gear is on.

20. Push the START button on the Router's Control Unit, and wait until the program has completely finished surfacing the table.

21. Clean off all debris by vacuuming, then by using a 3" wide paintbrush and compressed air, to clean out all the small passageways.

22. WARNING ! NEVER ATTEMPT TO MACHINE THE SURFACE OF THE TABLE. ALWAY USE EXPENDABLE MATERIAL ON TABLE TOP, THEN SURFACE IT.


DONE... YAY 

Now go make some really cool stuff !


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## The Hobbyist (Apr 25, 2015)

I could not imagine needing to mill down the aluminum table. You should have some sort of sacrificial material on the bed anyway, so the cutting tool does not cut into the table bed. Centerboard, or MDF,or nylon, or whatever you use, perhaps 3/8" to 1/2" thick and set up so you can still use your clamp down points ... that is what I would do. Then use the router to level the new spoil board and use it until it needs to be replaced again.

Don't start milling the aluminum!


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## Bmr1 (Oct 21, 2014)

I agree with Trevor, I've worked as a Tool & Die maker for 30 years unless something drastic happened to the surface of the machine table we used a perishable table top (alum) that could be machined flat as wear and tear took its toll. I use MDF as a perishable for my machine; alibi hate the dust but it only requires clean up periodically to maintain flat


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