Planing bowed boards on PT

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Am I doing it right?

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And you remove the weights.....SPROING!!! (Thank you, Mike and Dana ) ....the wood bends up again?

Concave up, weighted 'flat'(???) seems like being perverse for the sake of swiming against the tide. P!$$ poor publicity ( or is it notoriety?) attempt.

Sam, who can't wait until a weight slips and nukes a planer blade..."Shrapnelfreude"??
 
Here's my thoughs before I keep out of it.
Putting weights on a board crossing a spinning blade would get me shut down.
However I'm an employer and not a hobbyist so do as you please, just seems crazy to put loose weights on a vibrating board. However you're all grown men and the risk is up to individuals.
Not adverse to planing upside down when necessary, not the norm though.
 
Trevanion":ox794n8f said:
Am I doing it right?

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You've got the idea but rather over done it. The little weight placed centrally would be more than enough. But keep trying I'm sure you will see the point sooner or later.
Maybe later in your case. :roll: :lol:
What should be obvious is that the only risk is in being able to move the workpiece at all.
Joking apart - it works really well- bit of candle wax on the bed - push with push sticks, hands safely out of the way.
PS I'm interested in why such a simple and risk free idea causes so much alarm.
 
SammyQ":34grltrj said:
And you remove the weights.....SPROING!!! (Thank you, Mike and Dana ) ....the wood bends up again? ...
Nope. You've completely missed the point, which is that the weight is placed in the centre of the concave side of the board. Difficult to explain you just need to pay more attention and think about it a bit.
I'll do a little drawing if you still can't get it. But maybe you never will. :lol: Don't worry about it.
SammyQ":34grltrj said:
..
Sam, who can't wait until a weight slips and nukes a planer blade...,,
How and why would the weight slip?
 
doctor Bob":198ztoy4 said:
... loose weights on a vibrating board. ..
1. The weight is not loose - it's firmly held down by (guess what) its own weight.
2 The board is not vibrating because it is firmly held down by.. guess what? :lol:
Don't know why I bother - pearls before gammons - but there must be someone out there who gets the idea.
3 Don't worry about it chaps. Carry on as normal, take not notice of me - I wouldn't want to be responsible for you getting it wrong and doing something really stupid.
PS you could think of the weight as a "gripper block", except that instead of holding it down with your hand, perilously close to the cutters, it's held down by its own weight with your hands well out of the way.
 
Trevanion":22or68g1 said:
The high and mighty attitude is beneath you Jacob.
I'm just trying to explain something simple and useful so I really don't know what on earth you are talking about.
If somebody could say anything intelligent about my weight suggestion I'd be interested, but so far they haven't.
PS It works really well and quite safely, but please don't try it if you don't understand it.
 
I’ve come across the approach of bow down when surfacing a board enough times that I have tried it and added it to my working option. With certain boards I’ve found it an easier way to get a flat area that I can use as a reference and work from. Skip planing the ends of a board tends to cause vibration with some boards as this is when I swap to bow down.

Regards the weights in the boards I have concerns. I appreciate the analogy to the pressure applied by ones hands or a power feed however my experience with vibration is that it can result in a drastic reduction in friction. When vibrating a surface big heavy things can start to slide very easily, it’s the principal behind vibrating conveyors and the like. Trying to manage a lump of wood and a couple of heavy items would be to much to try to keep track of.

Fitz.
 
Fitzroy":3jcxb0w7 said:
I’ve come across the approach of bow down when surfacing a board enough times that I have tried it and added it to my working option. With certain boards I’ve found it an easier way to get a flat area that I can use as a reference and work from. Skip planing the ends of a board tends to cause vibration with some boards as this is when I swap to bow down.

Regards the weights in the boards I have concerns. I appreciate the analogy to the pressure applied by ones hands or a power feed however my experience with vibration is that it can result in a drastic reduction in friction. When vibrating a surface big heavy things can start to slide very easily, it’s the principal behind vibrating conveyors and the like. Trying to manage a lump of wood and a couple of heavy items would be to much to try to keep track of.
Fitz.
Er - no vibration involved, nor conveyors, nor sliding weights :shock: . The whole point of the weight is to introduce stability and eliminate vibration, like a power feed except that the weight moves along with the workpiece rather than just over the cutters.
PS for me it's not about whether I'm right or wrong (on this issue at least) I'm right, it works, it's more about how how to explain it.
PPS I've been at it for years but this idea only cropped up recently; maybe I have to appreciate why others don't cotton on instantly!
 
My point was missed.

Vibrating conveyors use the principle of vibration to reduce the friction between the surface and the items on the conveyor. It’s highly effective.

On my planer I find the cutting action results in vibration in the board, I feel it in my hands.

My concern is if any vibration is introduced to the board the weights may move much more easily than expected.

I appreciate the idea of the weights is to introduce mass to eliminate vibration. I can however see a situation when there is an unexpected outcome.

Fitz.
 
Fitzroy":14lm8x6t said:
My point was missed.

Vibrating conveyors use the principle of vibration to reduce the friction between the surface and the items on the conveyor. It’s highly effective.

On my planer I find the cutting action results in vibration in the board, I feel it in my hands.

My concern is if any vibration is introduced to the board the weights may move much more easily than expected.

I appreciate the idea of the weights is to introduce mass to eliminate vibration. I can however see a situation when there is an unexpected outcome.

Fitz.
The test is whether or not it works. In my experience it works. There have been no unexpected outcomes, no vibration, no slipping weights.
n.b. the weight is placed dead centre of the bow, convex face down. The only thing which could destabilise it would be setting the depth of cut so deep that it would overpower the workpiece plus weight. Set it for a shallow cut to start with, until you have the feel for it.
 
I'll use my power feeder, thanks. I value all the bits of my body remaining in contact with the rest. Wonder what HS&E would have to say about sticking weights on ? But then, hey, what do they know when we have the world's woodworking expert on this forum ?
 
Jacob":3u6l8a4m said:
I'm just trying to explain something simple and useful so I really don't know what on earth you are talking about.
Actually, no. You are taking a contrary position in order to cause a fuss. In other words, trolling.
If somebody could say anything intelligent about my weight suggestion I'd be interested, but so far they haven't.
Normally your nonsense is mostly harmless, but in this case you are advocating puting a heavy metal weight on top of a planer block. It is, as you know very well, a monumentally stupid idea, which doesn't even need countering, except that if some newbie such as myself can't see through the idiocy and has a go, someone may actually die. Show me the intelligence in advocating people kill themselves, please.
PS It works really well and quite safely, but please don't try it if you don't understand it.
"Hold my beer, and watch this!"
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Crack on, and have fun: by all means earn yourself a Darwin Award.
 
Trainee neophyte":29zmpme4 said:
,,,, you are advocating putting a heavy metal weight on top of a planer block...
No I'm not.
I put the weight on the workpiece. 5kg is not that heavy either = five bags of sugar*. The workpiece may weigh more. The anvil was Trevanion's idea. :roll:
OK if you don't get it don't try it, but if somebody did something monumentally stupid and dropped the weight directly onto the block it would wreck the cutters and probably jam the machine, but there wouldn't be enough power in the machine to actually throw the weight anywhere, other than nudging it out of the way. Which is rather the whole point - weights have inertia.
For me the most interesting thing about this thread is the strange panicky adverse reaction! I'm really amazed. Oh well.
Another advantage is that the firm 3 point holding (2 push sticks AND a weight) reduces or eliminates snipe. You get a very steady cut though you do need to push horizontally (the workpiece, not the weight) and not rock the boat
PS don't try it with 5 bags of sugar they won't balance and you'll get sugar all over the shop!
 
https://www.hse.gov.uk/simple-health-sa ... /index.htm

"As an employer, you’re required by law to protect your employees, and others, from harm.
Under the Management of Health and Safety at Work Regulations 1999, the minimum you must do is:
identify what could cause injury or illness in your business (hazards)
decide how likely it is that someone could be harmed and how seriously (the risk)
take action to eliminate the hazard, or if this isn’t possible, control the risk"

The hazard of the weight and push stick procedure is that you could damage your machine, however the risk of this happening would be very low, involving no risk to the operator.
Risk of damaging push sticks themselves is quite high and to be expected, but with no harm to the user
Compare hand feeding the workpiece: the hazard would be coming into contact with the cutter and the risk of this happening, as we know, is quite high - there are regular reports, here and elsewhere.
 
Given the prominence of planers and the longevity of their use in both the professional and hobby arena I would suggest that there is probably a really good reason the practice of putting loose weights onto your planing stock hasn't taken hold and become standard practice.

That reason is probably why the suggestion has caused such argument among the professional and well respected wood working members on this forum also.

It may seem like a good idea but it is potentially dangerous. If it were me I'd take that as a hint that the idea I thought was groundbreaking may well not be and in fact perhaps I should stop doing it, or certainly stop advocating it.
 
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