work bench top

[jussi]

covered in laminate flooring and trimed in hardwood.

Is the laminate flooring 1 piece? It's not the tongue and groove type is it? Is it glued, floor stapled, nailed down? Your top looks like it's all 1 piece, how do you make it look so seamless? thanks

[footprintsinconc]

from what i saw in the picture, its the tongue and groove strips of floor laminate. do i see it correct, scott?

[footprintsinconc]

plan changes

well based on all the replies, i am going to be making the following changes:

• no pine top anymore, the ripping and planing and selecting wood, etc is going to take too much time. instead i will go with the (2) 3/4" mdf boards with hardwood edge trim all around.
• also, based on what ken has said, i will now either raise the drawer section all the way up and leave the two sides open OR i may just add two horizontal (short direction) supports like i have at the ends just above either end of the drawer section of the table. This will effectively reduce the span from 6'-6" to 2'-6"
• i have reduced the horizontal supports (short direction) from 2.5" tall to 1.5" tall x 1.5" wide. total of 6 supports, double on the two ends and singles at both sides of the drawer section.
• i will go what with what tom does for portable 1/4" hardboard pieces. (tom thanks for clarifying that for me)

the only things still i still dont have answeres to are:

1. should i run a 1.5" x 1.5" support the lenght of the table aswell (between the two end supports)? Ken, did you have trouble span the short direction wihtout any sags and without supports?
2. how far can i cantilever the mdf without causing it to deflect while working on the bench? does anyone have any experience with that? this is going to help determine where the face vise will go.

EDIT: when i am gluing two pieces of mdf togather that are 3ft x 8ft, how do i do it to ensure they are touching onaother completely and no air pockets.... and what type of glue do i use?


thanks for all the advice and suggestions!

[siliconbauhaus]

I dont know if there's a fool-proof way to tell if there's air in there but I would suggest using screws as well. Do a 6" X 6" grid and drill your pilot holes / c'sinks and then flip the board over and do partial c'sinks to the pilot holes. this allows for any pulling of the mdf you're screwing into.

[Tom Miller]

• also, based on what ken has said, i will now either raise the drawer section all the way up and leave the two sides open OR i may just add two horizontal (short direction) supports like i have at the ends just above either end of the drawer section of the table. This will effectively reduce the span from 6'-6" to 2'-6"
• i have reduced the horizontal supports (short direction) from 2.5" tall to 1.5" tall x 1.5" wide. total of 6 supports, double on the two ends and singles at both sides of the drawer section.

Will these 1.5" tall supports be resting on the cabinet underneath, or will they be unsupported? Hopefully the former....

the only things still i still dont have answeres to are:

1. should i run a 1.5" x 1.5" support the lenght of the table aswell (between the two end supports)?

You might not need to, but if you can, and if it's not too much trouble....

My 3 layer MDF top is 6' long, resting on trestles about 4.5' apart, with 2 front-to-back supports equally spaced in between. (The supports are in a small gap between the cabinet underneath, and the bench top.) I occasionally check for sag, and any low spots are on the order of 1/64" or less.

[*] how far can i cantilever the mdf without causing it to deflect while working on the bench? does anyone have any experience with that? this is going to help determine where the face vise will go.[/LIST]

Again, it's a 3 layer top, so take this with a grain of salt. I have a fairly large (heavy) face vise on a 12" cantilever at one end, and it's doing fine.



Regards,
Tom

[footprintsinconc]

Tom,

thanks for the detailed reply.

the 1.5" will be supported at on the cabinet edges below.

thanks for posting a picture of your table. if you could, can you take a picture looking up from the bottom with the top drawers removed? another one showing how the top rests on the end supports, if that wont be a problem.

EDIT: another question, the edge trim is that like deeper than the 3 layers of mdf? and is the vice a face mount or mounted to the bottom of the top?

lastly, how are you measuring a deflection of 1/64?!

thanks a bundle.

regards,

[SARGE..g-47]

Omar...

Very little I could add on the top at this point. You seem to be settled on what your top will be made of.. size.. etc.., etc..

But.. I did notice you are concerned with that 6' un-supported span from end strecher to end streacher. Frankly, that would cross my mind as a concern also. So... may I suggest that you use my whale-back design. I have built a number of benches for myself and friends over the years and came up with an idea one day a while ago as I was looking at a whaling boat.

Why not craft a very sturdy runner (whale-back) as you metioned in earlier psot and tie it into the two end strechers with a saddle or lap joint as I do. This separates the weight of the 36" wide top into two 18" sections as it gives the open span back-bone. Not only does it do that, but it also gives additional torque to the whole base.

If you do hand-planing or intend to.. you cannot imagine the directional forces that is generated and translated to the table base. You are concentrating on the top.. and there are a ton of ways to accomplish that as the guys have pointed out. Whatever method you chose it should be fine.

But.... Don't over-look the base. To do so would be like putting all your effort in the pent-house of a tall building and forgetting that the foundation is the key to why the pent-house will or will not endure over time. Pay extra attention to structuring the base as solid as a rock. Good.. deep.. solid joints and try to structure it in a way each component can stand as independent but all components locked together become im-pregnable team.

A top is expendable IMO. The base is the real work-horse that should stand tall long after you have replaced many tops. Without a solid design and well achieved joints in that foundation.. the top is going to sit on shaky ground! My bench won't budge with the deep through mortises and tie in of components with various joints. And that's the way it was before I added the glue to the joints just for insurance.

Good luck with your bench..

Regards..

[footprintsinconc]

sarge,

to tell you the truth, i am open to any and all comments. my mind right now cant decide on anything, i keep getting different ideas and sometimes i just cant decide.

to add to the my options, last night, someone at work gave me a 52"x38"x1.5" thick maple butcher block counter top which he ripped out and replaced with granite. then i started thinking about another table top option, combination of the two materials to get 8'. before i read your post last night, i had drawn up yet another configuration for my table.

what type of wood did you use? do you have one whale back in the middle? the top looks like it is about 3" deep or is that just the skirt around the top? the face vice, do the rods go thru a hole that you drilled in the legs?

i dont know if what i am going thru is normal, but its exciting and frustrating at times . for the space that i have, i can only have one 8ft long bench, maybe this is why i am still undecided

regards,

[Tom Miller]

the 1.5" will be supported at on the cabinet edges below.

thanks for posting a picture of your table. if you could, can you take a picture looking up from the bottom with the top drawers removed? another one showing how the top rests on the end supports, if that wont be a problem.

EDIT: another question, the edge trim is that like deeper than the 3 layers of mdf? and is the vice a face mount or mounted to the bottom of the top?

lastly, how are you measuring a deflection of 1/64?!

So, the 1.5" supports are themselves only supported at the ends? I'd be concerned that those aren't beefy enough to keep the top from sagging.

My cabinet has its own top, with dadoed verticals between the drawers. I have ~1/4" shim boards on the top of the cabinet, directly over these verticals, running front to back, that supports the top. So, the ~4' span between the end trestles has two equally spaced supports. And, the end trestles support the top along their entire front-to-back span, so there is support at least every ~16", as shown:




(Since the cabinet has a top, pulling out drawers doesn't show anything.)

The edge trim extends ~1/4" below the 3 layers. I later decided I wanted this flush to make it easier to clamp things to the bench, so I filled in with 1/4" material as this was easier to do in place than flush trim the edging.

The face vise has it's back jaw buried behind the edge trim, but is mounted from below, like so:




I periodically check the bench top for sag with a 6' level and feeler gauges (OK, post-its ).

Regards,
Tom

[dramey]

I just built the workbench featured in "Wood Magazine's Best-Ever Woodworking Jigs, Homemade Tools & Shop Organizers 2006". The workbench I built is on page 110 and is very sturdy. For the top I used a solid core door from the local lumber yard. The door is 1 3/4" thick and made from 1 1/2" MDF with 1/8" Oak Veneers. It is flat and sturdy and I got a great bargain from the lumber yard since they had it in their inventory since 1999 and they sold it to me for $25.00. I am going to build another of these benches and use it for an outfeed/work table behind my table saw.

[Ken Massingale]

Omar,
You can't have too much support under the top. Tom's suggestion is very valid.
I used screws along with glue on the MDF one I did.
I would however suggest that you consider a solid door. It would save you lot's of time. Lowes and HD often have chipped ones cheap, regular price isn't far from the cost of the MDF (2 sheets).
We're looking forward to pics.

[footprintsinconc]

tom, thanks once again for the detailed response. i greatly appreciate this.

ken and dramey, i will now go to hd and look for the doors that you suggest.

i now may have a new layout for the bench utilizing the hardwood top and then creating two smaller pieces on the both sides of this maple top to get my 8ft that i am looking for. once i get that and have looked at the doors at hd/lowes, i will post it only if the numbers for the loads/deflections work out.

for the next week, i probably wont think of this too much, but i will try to find some time for the calculations. this is probably an over kill, but i need some direction number vise to see if it is ok, before i put it out to you all for your opinions (which are really helpful-thank you).

and most definately, once i get the plans done, i will take pics through out the process and will post them. i just need you all to bear with me and my (dumb at times) questions and help me thru this planning process.

regards,

[SARGE..g-47]

There is one major suppost under that bench, foot.. It's 4 1/2" x 3 1/2" and that's more that is necessary to get the job done. This top is made of laminated ply stood on edge and face glued 3' thick. The boarder or skirt is maple and their is a piece of maple ply insert on top which would sit with gravity, but there are 6 3 3/4" sheet metal screws that attach from the bottom to make sure.

The base is made of a single Doug fir beam I recovered in downtown Atlanta in an old civil war warehouse being torn down. I ripped it up and latter laminated it as I decided to build this one from scraps laying around.

This is just one I have built. I have built them from yellow pine, maple, beech and pecan. I built a bench about two years ago that was made from shorts (maple scraps no longer than 13"). I was allowed to use a commercial finger jointer at a freinds business and the whole top was staggered pieces finger jointed together. Everyone told me it wouldn't work and that it would warp.

I wish I had it back (gave it to my BIL) and it has not had to be flattened in two years. It has moved no more that 1/8" over-all with expantion and contraction and just keeps coming back to square. ha.. ha...

Just build the base sturdy. If you don't like whatever top you decide on.. you can get rid of it and build another till you get a comprimise you like. You will be fine as long as you don't over-think it!

Regards...

[JimD]

My top is also laminated. I had a large piece of 1/4 luan plywood available when I made it so that is the top layer. It is looking pretty sorry, however, so I should probably go get a piece of masonite.

I have one layer of 3/4 plywood and then a stress skin arrangement that goes out only as far as the legs. I think Norm did something like this because I remember I copied his rolling arrangement. My oak edging is only about an inch tall - covers the plywood and the mdf or plywood top.

I do not use bench dogs. I clamp a piece of scrap from side to side of the top. I have some plastic bench dogs I got from Rockler that go in round holes, I just have never gotten around to drilling the holes. Clamping the scrap in place takes a little more time than setting a dog but only a little.

I am not a mdf fan for structural appliations. It will probably work but I like plywood better if it will see any significant load. Maybe that is just my issue. The strength is clearly less as you could see in a sagulator calculation of shelving strength. Still an inch and a half should be pretty stout.

Jim

[Tom Miller]

I am not a mdf fan for structural appliations. It will probably work but I like plywood better if it will see any significant load. Maybe that is just my issue. The strength is clearly less as you could see in a sagulator calculation of shelving strength. Still an inch and a half should be pretty stout.

MDF definitely has a tendency to sag, which is why an MDF top needs more support than a hardwood top of the same thickness. E.g. a hardwood top only needs the support of the two trestle ends, whereas my top needs two extra supports in the middle. But as long as it's well supported, I think it's exceptionally tough.

How is your luan ply top not holding up? I imagine it must pick up a lot of dents in use. My BB-topped outfeed table has a lot of denting (looks like scratches), whereas my mdf bench top doesn't show anything like that. I think a 1/4" hardboard cover would also hold up very well.

Regards,
Tom