Thread: HELP - Jointer problem driving me crazy

It sounds like you have a resonance problem, ie, some part of the cabinet is resonating with small vibrations from the motor.
You could try using thick/stiff rubber gaskets washers between the motor and cabinet although this doesn't usually do much.

Even though the motor runs smoothly on the bench it can still cause cabinet panels to vibrate.

Maybe check if any of the panel welds have cracked first

To find the offending panel is tricky because the culprit panel will often set other panels vibrating.
One way to to find and change the resonant frequency of a panel is to place or attach a large/heavy piece of steel (or lead) onto the panel.
You can drill holes etc but that's going a bit far especially when you don't know which panel it is.
However 4 strong REE will stick even a very heavy piece of steel to the panel certainly good enough for a test.
Pity your'e not closer as I have the perfect thing for the task - a 20kg bar magnet. One problem with that is once it sticks its a nightmare to get off so I put a thin sheet of plastic underneath it so it can slide off.

Reminds me of a similar situation at a high rise research lab in San Diego. We were using incredibly sensitive electron detectors, but nosies like slamming doors and motors/fans from the rest of the building were sending vibe through the building onto the experimental apparatus. We were going to fork out 1000's of bucks for a special anti-vibe table but ended up just putting a lead brick on top of it and it worked.

I'll be interested to see what you find out.

Another rough & ready method to dampen panel vibrations is to cut a length of timber slightly longer than the internal dimensions of the cabinet & "brace" them internally by forcing the "braces" into position. Check the tightness of any bolts in the jointer chassis / cabinet.

Is the machine on a level stable base?

Thanks for the replies and will try out the timber braces and report back

In addition to what has been said above, stick polystyrene foam to the panels (inside) or that spray on foam.

Take the knives out and the wedge blocks and run it like that, if it’s a straight knife head. If it’s still there, Take the head out and take it to an engineering shop to get the balance checked. Likewise check all bolts and fasteners. I had one once that had been dropped and the cabinet was twisted, it was Nearly impossible to repair it.

My old 9” Wadkin Bursgreen jointer suffers from at least two sources of vibe noise.
The belt guard, possibly one of the twin belts might be actually hitting it.
Next is the fabricated aluminium Surety style guard wot rests on the bed rattling away
I guess I should put some rubber on the edge where it touches
H.

What Riverbuilder said.

It sounds like you bought it second hand?

This is probably a silly question as I'd hope you've sharpened the knives since you bought it, but... you have inspected the head and removed the knives at least once in that time? All the blade fixtures are present and in place and none of the knives are broken at one end?

I've seen used jointers for sale with missing bolts, mismatched knives, etc. and had the seller inform me "I can fire it up if you like."

Most jointer/planers I've used were noticeably noisier when the cutting head was out of balance even by one grub-screw's worth of weight.

Originally Posted by riverbuilder

Take the knives out and the wedge blocks and run it like that, if it’s a straight knife head. If it’s still there, Take the head out and take it to an engineering shop to get the balance checked. Likewise check all bolts and fasteners. I had one once that had been dropped and the cabinet was twisted, it was Nearly impossible to repair it.

He's already tried running it without the belt and he still gets the vibe so it's unlikely to be the cutter head.

Originally Posted by BobL

He's already tried running it without the belt and he still gets the vibe so it's unlikely to be the cutter head.

Ok, missed that bit. So it’s most likely the motor mounts. Push and pull everything until you find something that is moving that shouldn’t be. The only other thing could be the motor pulley is floating on the shaft? Seen plenty of grub screws come out of pulleys.

Originally Posted by riverbuilder

Ok, missed that bit. So it’s most likely the motor mounts. Push and pull everything until you find something that is moving that shouldn’t be. The only other thing could be the motor pulley is floating on the shaft? Seen plenty of grub screws come out of pulleys.

He's tried the motor on teh bench and that is fine too - he didn't say if the pulley was still on there - I assume so.

Hi everyone,

At the moment the machine has the belt taken off and the problem persists. The pulley is on the motor and i have checked the screws etc. Will try to wedge some timber inside today hopefully.

Thanks to everyone for their input.

Hi everyone and thanks for all the replies.

I have tried putting my knee with quite a bit of force on the front panel and this alleviates the noise to some extent. The front panel is quite thin and tack welded every hundred mm or so internally. Will try a few braces internally but it is not easy to do.

The rubber belt is removed at the moment.

I have emailed the service representative as directed to from the Jet website and am awaiting their response.

There is no current Jet representative in Australia.

hi all,
thanks for all replies and suggestions,
it appears that I have been locked out of this thread so i will not reply further
Peter

Hi again, it appears that i am no longer locked out.

I have heard from the Jet representative who is referring me to another fellow so am awaiting his contact.