Change spoilboard?

[GJHall]

I am finally about ready to get this machine going. I have base on the table with 3/4" baltic birch and them 1" plywood that was available cheap.
I want to put a 1" MDF sheet on top for my spoil board and am looking for how you would hold it down.

I was thinking to glue it but then how do you change it when the time comes? I have heard there are ways to screw it down, but not sure how. This is not a vacuum set up.

I am new to the router world, as I am a welder by trade and cut with a cnc plasma.

Any advice is greatly appreciated!

Thanks

Gary

[RyanS]

There are a million different answers to this question.

The simplets way is to put a screw in the four corners. Preferably where you won't be milling, of course. Simple and effective, but sometimes time consuming and it will make a mess of your spoilboard quickly - so you will have to resurface it every so often.

There are some plastic nails (RAPTOR composite nails) for nailguns that I hear work really well for soft / plywood / mdf. Simply tack em' in and don't fret - you can mill right through them. Haven't used them - but have wanted to. I use mostly hardwoods, and unfortunately the RAPTOR nails don't work so well through them from what I've heard.

You can also get some T-tracks and hold down clamps. This is what I use currently. My favorite clamps are the Shop-fox D3347 cams. They sit about 1/4" high off the spoilboard - and are great for holding things. They are quick and easy, and my favorite method so far.

I'm sure others will chime in with other ideas. Can't wait to hear some!

[Leo]

You can make a series of counter sunk screw holes and flat head screws. Make the depth of the counter sinks deep enough so the heads are at least 50% of the thickness of the spoil board deep.

[PaulRowntree]

Depending on the framing & supports below the spoilboard, nylon bolts with recessed heads may be workable.

[Adrian]

I glue my spoil board down and then just glue a new one down when it's been resurfaced enough times to be down to the original surface again.

[GJHall]

Thank you for your replies.

I think I will glue it down and surface it.

Thanks

Gary

[woody53]

I'm like ,Leo. I use 3/4 mdf and countersink holes 3/8 deep and screw with flathead screws. Can surface spoilboard many times and have never hit a screw. Maybe I'm lucky , but have done it like this for 3 years.

Dave

[GJHall]

I glue my spoil board down and then just glue a new one down when it's been resurfaced enough times to be down to the original surface again.

Can you explain what glue you use for gluing sheets of mdf together? I want to try doing this and then I will put T tracks on and then put my new board on in sectionss

I might even just glue the full sheet on and them route out for the tracks.

Gary

[Adrian]

I just use standard woodworkers white glue (PVA). Spread it thin with a card on one surface and weigh it down overnight.

[AlanAndrews]

Yes I agree with Adrian.

PVA woodworkers glue with mdf spoil board - 12 thick.

Once dry then surface the top face and repeat periodically as the spoil board wears.

Then simply repeat for replacement spoil board.

I made the spoil board the same size as my machine capability. This is a visual prompt when positioning new material for machining.

I also ran a 3 mm end mill around the outer faces to ensure squareness.

I use 2 strips of 25 thick mdf on x and y axis - screwed into permanent M6 threaded fixings on the vacuum table, and butted to the spoil board to act as material positioning stops. These strips are in turn drilled and fitted with threaded inserts to which I attach my clamps.

The spoil board is drilled with 12mm dia holes that I can also attaching clamping wedges.

[GJHall]

Thank you!
I will give it a try this week.

Gary

[pro70z28]

I have 3/4" oak plywood as a base with a 3/4" MDF spoil boar screwed 12" on center so it stays flat. I screw it down from the bottom side and I use aluminum screws, so if I happen to hit one it doesn't hurt the bit. I use 1.25" screws so it's not likely I'll ever will hit one.

[potzmannwoodshop]

Thank you for your replies.

I think I will glue it down and surface it.

Thanks

Gary

If you are setting up a vac table the PVA glue will prevent air from moving through the spoilboard. Just something to remember.

[Adrian]

He's putting t-tracks etc in it.

[AlanAndrews]

I have matching holes through the vacuum table and spoil board.

I can then use the holes in the spoil board as location points for clamping.... dowels seat through the spoil board and vacuum table top.