Workbench Tension/Vibration

[Osvaldd]

Few weeks ago I finished my workbench. Its an English style bench made with construction grade softwood, 3" top, 4" thick legs, two shelves, tool well, it’s 70" long and 30"wide, it weighs a ton I can barely lift one side. It's all mortise and tenon joinery.
I messed up somewhere, the bench feels super solid yet tense, like a drum. If I hit the top or the sides with a hammer or even a fist it resonates and vibrates, planing something difficult like end grain is a nightmare... :evil:

 

[sammy.se]

Oh no! It's like the millennium bridge when it first opened.

Sorry, don't know how to help...

Sent from my SM-G973F using Tapatalk

 

[Osvaldd]

Its OK sammy, it's more of a rant rather than ask for help.

 

[Trevanion]

Try something soft under each leg like a piece of cork, that may or may not help.

 

[Osvaldd]

Good idea, I think I have a few of them kneeling pads somewhere. Will try that tomorrow.

 

[katellwood]

try a diagonal brace across the back

 

[Ttrees]

It sounds a strange occurrence to me, utuber Jay Bates mentioned he prefers his softwood bench compared to the hickory one he built because of the noise.
Not noticed any ringing with the hefty laminated iroko slabs I have though.

Could it be the floor in your shed that has a thin skim, or has some voids or pipes underneath?
I have caps on the legs of my bench as to not blow out the end grain if dragging it,
and also use bearers for chopping mortises which might be why I don't have any issues.

It might be worth doing a few tests to figure out if you can pinpoint where its coming from,
like giving a few blows with a hammer on some lump of timber positioned where the legs are.
Maybe giving a few taps on the shelf of your bench, to see if its the top or the frame that's the issue.

I think it might be sorted with feet or pads.

I can't imagine planing would cause the issues you mention, unless your work is some distance away from being secured, you should not expect vibration.

 

[Orraloon]

The bench looks to be a solid beast but usually if they dont feel sloppy when you try giving then a good shove both long and across ways they are good enough to plane on. Sure your plane is not the issue as in not sharp enough, blade chatter or taking too deep a cut. Does it happen when you plane both along the bench and across the bench? As the others said perhaps some rubber or something under the feet. These kind of things can take a bit of detective work to figure out but when found usually have a simple explanation.
Regards
John

 

[sunnybob]

That floor is rough cast concrete, put those high and low ridges against the 4 wooden legs (which have to be at the least slightly uneven in length) and the whole thing is resting on a square inch at most.
Anti vibration rubber pads will solve your issues.

 

[Osvaldd]

I added soft feet and braced the back in X pattern. Its still vibrating, driving me mad.

 

[That would work]

How about fixing it to the floor with a steel bracket on each leg?

 

[Osvaldd]

aye, either that or bolt it to the wall but I do like the option of having a portable bench for those sunny summer afternoons.

 

[Phil Pascoe]

Do you have problems when doing anything other than planing end grain?

 

[Jacob]

Looks like a very conventional bench and should be fine.
Maybe not as solid as it looks: some odd details? e.g. legs should be housed into the aprons.
Legs and top/bottom rails (at each end not lengthways) should be solidly morticed together. I see no through mortices in the legs?
A blind mortice is good for locating a piece but not very structural unless also pinned and/or draw-bored through. Still not as good as a wedged/through mortice.
PS I think that's most likely it - not as solid as it looks due to not very strong/stiff joints. Perhaps.

 

[Osvaldd]

The bench just feels odd, kinda rubbery and elastic. When I clamp a piece of wood in the vice, that piece becomes part of the bench and thus transfers those vibrations to and from. I noticed chatter or skipping when planing occurs a lot more often(need to sharpen, I know).
For the past year I have done most of my woodworking on a pair of trestles and latter a garden table I have not experienced anything like that.

 

[Osvaldd]

@ jacob,its not a through tenon but its 7cm deep, the leg is 9cm
Legs are housed into the aprons but I did not use wedges I just glued them and used heavy duty screws.

 

[That would work]

I would have gone for deeper aprons (and deep for the whole length of them rather than cut out)

 

[Jacob]

The bench just feels odd, kinda rubbery and elastic. .....

Yep. Not well jointed, in spite of appearances.
Sounds like start again?
n.b. not the fault of any one joint but maybe they all just a bit too floppy?
PS that "tension, vibration" sounds very much like what you get when trying to plane or saw on a B&D workmate - just not solid/rigid enough.

 

[sunnybob]

put some sandbags(heavy but soft) on the bottom shelf, see if that solves it.

 

[Osvaldd]

The bench just feels odd, kinda rubbery and elastic. .....

Yep. Not well jointed, in spite of appearances.
Sounds like start again?
n.b. not the fault of any one joint but maybe they all just a bit too floppy?

hm, I dont really think so, it doesn't feel loose or sloppy. In fact the opposite, you can stand on it and dance, jump up and down all night it will not fall apart. If the joints were dodgy it would not transfer vibrations, it would dampen them .