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Forum topic by Nashvillian posted 01-09-2022 11:50 PM 1338 views 0 times favorited 22 replies Add to Favorites Watch
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Nashvillian

32 posts in 376 days


01-09-2022 11:50 PM

Topic tags/keywords: question trick tip work table

I made my work table when I was first starting and I used insufficient support to keep it from sagging. There are dips wherever there is not a leg to support it.

I am constantly running into situations where I need a good, flat surface to line things up properly. I can’t move the project elsewhere because I live in a house that was built around 1945 (about 77 years ago) and I don’t think there’s a flat surface anywhere—wood floors, basement concrete, garage concrete, two concrete porches—none of them are reliably flat.

Eventually, I’ll build a proper table, but I don’t want to tackle that until I’ve had more experience.

As a stop-gap measure, I’ve had an idea to get sturdy piece of something that’s about 4 ft. by 4 ft., lay it on my current table and use shims or other support make sure it’s level in all directions. If I get new sags in the underlying table, I can always adjust the shims/supports.

My question is… what material would be best to accomplish this? Plywood? MDF? Melamine? Something else?

If you have any tips, I’d love to hear them. (Or is this just a bad idea?)


22 replies so far

View Madmark2's profile

Madmark2

3439 posts in 2047 days


#1 posted 01-10-2022 12:53 AM

Shorter span than 4’ is needed. Double 3/4” material glued face to face and strong aprons. Make all legs identical and shim the feet for level.

-- The hump with the stump and the pump!

View Aj2's profile

Aj2

4454 posts in 3257 days


#2 posted 01-10-2022 01:50 AM

What I do is the saw horse approach. What you will need is a long level and a jointer capable of making straight edge at least 8 ft.
First I set up the saw horses using the level and winding sticks. Then I add 2 2×4s that are jointed and planed parallel they must be dry. I use the same process on the 2×4 level and winding sticks.
All shimming is done at the feet of the saw horses.
When I get the 2×4s done I build a grid notching more 2×4 together for 4×8 sheet of melamine.
I uses to build a torsion box from mdf. The way I do it now everything can be dissembled and stored in my shed unlike a torsion box.
I would advise against working off the ground unless you don’t mind dirt and rocks in your projects.
Good Luck

-- Aj

View BamaCummins's profile

BamaCummins

131 posts in 5035 days


#3 posted 01-10-2022 01:57 AM

Look at what this guy did to prepare for massive carriage doors. Will work for now until you can build something more permanent.

https://www.youtube.com/watch?v=PEmhfZg8NY0

-- "I don't know, we haven't played Alabama yet." -- Vince Lombardi after being asked what it felt like to be the greatest football team in the world just after winning the '66 championship game.

View HowardAppel's profile

HowardAppel

160 posts in 4493 days


#4 posted 01-10-2022 02:31 AM

You might also look at the YouTube channel for King’s Fine Woodworking—The Extreme Torsion Box Assembly Table series. He does a VERY good explanation of how to create a flat, level surface using sawhorses.

View JohnDon's profile

JohnDon

243 posts in 2628 days


#5 posted 01-10-2022 05:08 PM

You might be able to straighten your work table surface by bolting a couple of lengths of angle iron (or repurposed steel bed frames) on the bottom.

While longer and narrower than 4×4’, you can built an easy, flat and cheap worktop by buying a slab hollow core door (search CL or Habitat store if one nearby- cosmetic defects are irrelevant) and cover with mdf or plywood to fit.

View splintergroup's profile

splintergroup

6950 posts in 2681 days


#6 posted 01-10-2022 05:48 PM

+1 on the hollow core door.

These are basically a torsion box on the cheap and are light enough to not deflect under their own weight. On their own they make a great platform to construct a beefier torsion box structure.

View bbc557ci's profile

bbc557ci

698 posts in 3533 days


#7 posted 01-10-2022 06:43 PM

Similar situation here, old crooked house. My bench consists of a pc. of 2 ft. x 8 ft. 3/4 plywood over a 2×4 frame. I knew it wouldn’t be all that great when I built it but figured I’d build a good/proper work surface when time allowed. That was about 6 years ago, hmmmm…. Anyways, so far when I’ve needed a good/flat surface for a glue up, clamping, or whatever, I use the top of my Unisaw.

I’ve seen marble top tables and other good size pieces of marble top furniture on Craigslist and Farcebook for pretty reasonable prices, and have thought about grabbing one as it should make a decent surface for glue ups and the like. Just a thought…

-- Bill, central NY...no where near the "big apple"

View Nashvillian's profile

Nashvillian

32 posts in 376 days


#8 posted 01-10-2022 07:12 PM

While longer and narrower than 4×4, you can build an easy, flat and cheap worktop by buying a slab hollow core door (search CL or Habitat store if one nearby- cosmetic defects are irrelevant) and cover with mdf or plywood to fit.
- JohnDon

Thanks!

Why hollow core instead of solid core? Wouldn’t solid core stay flatter longer?

View Nashvillian's profile

Nashvillian

32 posts in 376 days


#9 posted 01-10-2022 07:19 PM

and are light enough to not deflect under their own weight.
- splintergroup

Thanks for the response! Could you expound on that a bit? If a solid core door were shimmed to be level on an un-level surface, would it be more apt to bend, sag or warp than a hollow core door?

View ironchefboyardee's profile

ironchefboyardee

3 posts in 134 days


#10 posted 01-10-2022 07:41 PM

I would think that solid core may be more rigid, but heavier and more costly than necessary. My father had a solid core door as his desktop for decades, supported by filing cabinets on each end and it never had noticeable sag.

You might also look at the Bora Centipede. I use one with a sheet of MDF. They sell matching MDF tops with MFT/3 style holes in them. If you aren’t going to use the hole pattern for clamps or track saw use, you may be better off just throwing a hollow core door on top of it when in use.


and are light enough to not deflect under their own weight.
- splintergroup

Thanks for the response! Could you expound on that a bit? If a solid core door were shimmed to be level on an un-level surface, would it be more apt to bend, sag or warp than a hollow core door?

- Nashvillian


View controlfreak's profile

controlfreak

3742 posts in 1060 days


#11 posted 01-10-2022 08:03 PM

I had a 10’ oak wide solid door between file cabinets as a desk for years, it was great for rolling out plans. It DID sag in the ten years I had it. It was so damn heavy I left it there when I moved out. Couldn’t fit it up the stairwell so I had to get it to the fourth floor on the top of the elevator car.

View splintergroup's profile

splintergroup

6950 posts in 2681 days


#12 posted 01-10-2022 08:26 PM

Big thing is price difference and solid core doors can be warped a tad depending on their construction materials.
Hollow core doors are usually thin (1/8”) plywood over a cardboard ribbed grid and wood frame. If you cut into it, you would have to replace the missing frane edging.

A quick look on the Lowes website shows a flat, hollow core flush door at $54.

A solid core runs $101 (both are 32” x 80”)

The solid doors that have an MDF core (office/commercial) tend to be nice and flat. I have one, but it is heavier than I can carry. You state that your short term goal is a 4×4 and cutting a door down would be a waste.

The hollow core would get you started by being able to shim out any rocking on your bench, then if your projects are light enough you can use it as-is. Alternatively, you mention making something more permanent in the future and the HC door would be a good way to make a 4’x4’ torsion box using MDF or other flat material to make a nice, exceptionally stiff platform (instructions are everywhere). I’m just thinking of how you can achieve a flat surface without beginning with a flat surface in the most economical way. 8^)

You could even temporarily use a door removed from somewhere in your house (covered in plastic for protection) if you have one to save the initial expense.

Of course a solid core door will allow for more weight without deflecting as much, just depends on how long you intend to keep it.

Either way you need to eyeball the door before buying because I have seen some ugly stuff in stores.

View mnguy's profile

mnguy

321 posts in 4857 days


#13 posted 01-10-2022 08:32 PM

I have used a solid core door as my workbench top for 15+ years and while it is well-supported, I can’t believe it wouldn’t stay flat under normal use unless very poorly supported and left heavily loaded in the middle. While more expensive than a hollow core door, you might also be able to find one on CL or at a building salvage. Using a hollow core door as a flat platform for building something more sturdy is also a great idea.

I also built two torsion box / I-beams for assembly on saw horses in the garage – those have also served me well.

View HapHazzard's profile

HapHazzard

266 posts in 2327 days


#14 posted 01-10-2022 09:29 PM

Backer board. It has to be flat because it’s used as a substrate for laying tile. It’s also reasonably strong, but it chips, so you might want to cover it with a thin piece of plywood or MDF.

-- Unix programmers never die; they just > /dev/null

View CaptainKlutz's profile

CaptainKlutz

5610 posts in 2953 days


#15 posted 01-10-2022 09:47 PM

+1 solid core door

Built 3 work benches using 36×80 solid core door as top 33 years ago in my first dedicated shop. Had one painted ‘dirty’ metal working bench with 16ga steel plate on top, and two ‘clean’, poly coated hobby benches.

BIL wanted clean one when I moved cross country, and could not take all three with me. He still uses that bench in his garage. Had to add a new 3/4” plywood top to his bench about 10 years ago, as farm implement repairs gouged the top pretty bad.

Sold my last remaining bench last year due down sizing. Picture from sale:

Added an apron to keep it flat while heavy stuff was sitting on top, and as attachment for legs. Used four 4×4 posts for legs, and a couple shelves in the base. Top stayed flat entire time I owned it. Was my main assembly and glue bench for many years.

Top would lift off, to make it easier to move to a basement shop or guest room to work inside.

Solid core door can make a ‘forever’ work bench if you take care if it.

The only wood working skills needed to make that solid core door work bench are; a circular saw, hand drill, screw driver, and paint brush.

Suggest you stop waiting for skill improvement to make flat work bench.

YMMV

-- If it wasn't for bad luck, I wouldn't have no luck at all, Doom, despair, agony on me… - Albert King - Born Under a Bad Sign released 1967

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