How to keep hardboard flat on MDF bench?

[Ken Cohen]

Hi --

A simple question, but looking for anyone's successful experience. I have a basic glued MDF bench with hardwood rails that capture 1/8" tempered hardboard.

I built the bench last year and quickly found that the hardboard would not stay flat on my surprisingly flat MDF base.

I tried screws around the edges, but found that the hardboard kind of puckered between the screws.

I switched to carpet tape -- strips every 6" or so across the bench. It held everything flat, but was thick enough that there were "waves" between the strips. (And I found out the hard way that carpet tape is very sticky and hard to remove).

Having just replaced the hardboard top, I'm wondering if anyone has a better attachment technique.

Thanks for the suggestions.

Ken

[Aaron Wingert]

Contact cement, just like you'd apply formica. Yeah, it is more permanent, which might not be what you're after. I'd recommend doing the underside in the same hardboard as well to create a balanced panel. It has a much better chance of staying flat long-term if it has the same material on each face.

[Eiji Fuller]

try 1/4" mdf

[Robert gree]

Before i sold my old assembly table, i had good luck with just placing drywall screws on a 16" grid

[Ken Cohen]

Thanks to all for the suggestions.

Brads seemed like a good, fast solution -- but, when I tried it, my nail gun left the surface of the tempered hardboard dimpled.

So I switched to four rows (lengthwise) of countersunk #4 brass screws spaced every 8" or so. Because I'm using only 1/8" hardboard, I needed to proceed carefully with the countersinking, slowing down what should have been a quick operation. Still, it was only an hour of work. I chose brass based on the probably absurd notion that my chisel will survive a collision with brass better than zinc.

Top is now dead flat vs. MDF and easily removable. Hopefully, it will stay that way for a long time.

Thanks to all for the help.

Ken

[Jason White]

Are you using hardboard with the "waffle" pattern on the back? That can cause cupping/curling.

Try using "service tempered" hardboard. It's smooth on both sides and likely won't cup as much as the cheaper stuff like you find at Home Depot. It's harder to find, though. You might have to go to a panel/plywood supplier that sells to professional cabinet shops.

Jason


Hi --

A simple question, but looking for anyone's successful experience. I have a basic glued MDF bench with hardwood rails that capture 1/8" tempered hardboard.

I built the bench last year and quickly found that the hardboard would not stay flat on my surprisingly flat MDF base.

I tried screws around the edges, but found that the hardboard kind of puckered between the screws.

I switched to carpet tape -- strips every 6" or so across the bench. It held everything flat, but was thick enough that there were "waves" between the strips. (And I found out the hard way that carpet tape is very sticky and hard to remove).

Having just replaced the hardboard top, I'm wondering if anyone has a better attachment technique.

Thanks for the suggestions.

Ken

[Prashun Patel]

+1 to Eiji's suggestion (for next time).
I have 1/4" HB on my mdf top. Never tacked/taped/glued/screwed it. Lays flat. It's hard on both sides which might help too.

If you wax or oil it, It won't need replacing for a while.

[Howard Acheson]

>>>> hardwood rails that capture 1/8" tempered hardboard.

That's the major cause of the problem. 1/8" hardboard was not a good choice. 1/4" is what will work much better.

You can glue the 1/8" down or, if you still want a removable top, buy a sheet of 1/4" and make a new one.