# Replaced Spoil Board and It Looks New Again



## cjskelton (Feb 27, 2015)

After almost 3 years of use, the MDF spoil board on my Probotix Meteor needed replacing. I had surfaced it multiple times, it was riddled with lots of screw holes, it had scars from too many deep cutouts and was sagging. Since I was going to have the spoil board off, it was a perfect time to add some supports to the frame. Probotix builds their machines with an open frame which is great for adding a 4th axis or special fixtures like our very own 4D uses. I'm not planning on adding either of these options so I'm beefing up the frame to try to stop some of the sagging of the MDF. I guess time will tell if I'm successful. Here are before, during and after photos. Like I said, it looks like a new machine again. I cut new grid lines in the board using a Probotix provided file.


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## Semipro (Mar 22, 2013)

Well the bottom picture does look much better!


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## difalkner (Jan 3, 2012)

Looks great! I wouldn't want to use it. :wink:

David


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## honesttjohn (Feb 17, 2015)

Good job Jay. What kind of nuts and bolts did you use to fasten the spoilboard down with? Nylon, metal, or combination?

Have we had these 3 years already?? Doesn't seem like it.


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## cjskelton (Feb 27, 2015)

honesttjohn said:


> Good job Jay. What kind of nuts and bolts did you use to fasten the spoilboard down with? Nylon, metal, or combination?
> 
> Have we had these 3 years already?? Doesn't seem like it.


I just used the original metal hex head screws. Yep, it's been since April 2015 for me. Time flies, doesn't it HJ?


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## 4DThinker (Feb 16, 2014)

Looks great cj! Now that you have it braced and flat a trick I use to do less damage to the spoil board is:

- Set the Z origin on top of your board in the software, 
- Touch Z off on the MDF bed, then enter a negative value of the material thickness instead of zero. For a .75" board use -.75.
- Don't set any through cuts deeper than your material thickness. 

This will make sure the bit cuts down to the MDF, but not into it. It also accounts for any thickness variations or warping your board may have. 

4D


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## marecat3 (Nov 30, 2010)

Looks great. I love having new spoiler board, not that I get one but every few years.


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## Scottart (Jan 8, 2015)

Pretty. don't touch it .. 

So chat about the gridding that is on it. Is that dimensional for lay out, or is it drilled for a vac table. 

Looks great. I need to start over and follow 4 D's rules for not eating spoiler boards..


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## difalkner (Jan 3, 2012)

I'd love to do that but a lot of what I do is pockets from the top surface to a dimensioned value, regardless of the thickness of the material. So if I need a pocket 0.255" deep from the top surface then I have to zero off the top surface. Either that or measure the thickness of each piece precisely and then modify each file to fit that particular work piece - too much effort for that. I'll just have to live with the knowledge my spoilboard will be spoiled. :wink:

David


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## honesttjohn (Feb 17, 2015)

4DThinker said:


> Looks great cj! Now that you have it braced and flat a trick I use to do less damage to the spoil board is:
> 
> - Set the Z origin on top of your board in the software,
> - Touch Z off on the MDF bed, then enter a negative value of the material thickness instead of zero. For a .75" board use -.75.
> ...


I wouldn't trust my limited abilities to cut it that close. So I just put a cardboard separator on the spoilboard under my material. Can use it several times, and then pitch it. Only cost 25-50 cents depending on the size. I also will profile cut to just above the bottom, and then finish cutting on the band saw and sand the edges smooth. I think 4d turned me on to that trick.


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## cjskelton (Feb 27, 2015)

Scottart said:


> Pretty. don't touch it ..
> 
> So chat about the gridding that is on it. Is that dimensional for lay out, or is it drilled for a vac table.
> 
> Looks great. I need to start over and follow 4 D's rules for not eating spoiler boards..



I use to grid to make sure my work-piece is square to the table. I also have a file to drill holes for threaded inserts. I don't use clamps so I don't need the inserts. I'd love to have a vacuum table but that's not gonna happen.

I like HJ's idea for using cardboard under the work piece. I'll have to give it a try.

Jay


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## 4DThinker (Feb 16, 2014)

On our CNC shark with the aluminum t-track bed I've also been using cardboard (or scraps of 1/8" plywood) to protect the bed. 

4D


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## difalkner (Jan 3, 2012)

I may do that whenever I get to my second spoilboard. Right now I'm still on my first one and consider it a *SPOIL*board, so I use it like that. :grin: I cut into it, drill holes, have locating pins for templates and fixtures, etc. but I may try and preserve the next one for a while. I don't try to abuse it but figure it's there to be a sacrificial and replaceable piece of the machine. 

Although, this one is going on 15-16 months and I will probably surface it another 2-3 times before I replace it. And the replacement is standing in the corner so it's already cut and ready to drop onto the machine.

David


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