spindle moulder tooling

[wallace]

Just curious what it means when a cutter block has limiters. I understand the limiters are a safety feature of modern tooling. How do the limiters work. Surely if your daft enough to have your hands near to get cut how do they stop damage to pinkeys

 

[kinsella]

Wallace
I'm not an expert and I've only used my spindle moulder a few times so far. But the limiters are to reduce kickback as it limits the amount of material that reaches the cutter and ergo if your pinkey does the same then it too limits the amount of damage. But damage there will be if you get a pinkey near a cutter head. I've sure a more established veteran will give more detail.

 

[katellwood]

Think of the old square spindle blocks. if you were to catch your pinkey on them then there is a strong possibility you could loose your arm, this is due to the size of gap created when the flat part of the block passes the infeed fence no matter how close to the cut line you set the fence.

However with a round block apart from the depth of the cutter the gap between the fence and block remains constant and if set correctly is much smaller than the size of your finger (especially with a false fence which should always be used). The distance the cutter protrudes from the block will dictate the amount of material that can be removed in each pass (be it wood or flesh) and on blocks without limiters this too can be excessive which can result in serious kickback of the material being fed (especially when being handfed where the speed of feed is not constant).

limiters reduce the amount of material that can be removed in each pass to 0.9mm (if memory serves) again wood or flesh so injuries are kept to a minimum should the unfortunate happen (so you can still order five pints from a distance )

Another analogy, think of the difference between a cutthroat and a safety razor

 

[custard]

Limiters are about reducing the risk of kickback rather than reducing the amount it could take off a finger. Even if it were only taking a 0.5mm cut you've got to remember that it would be taking that 0.5mm not once but 6000 times a minute, that's two inches of finger getting shaved off every second!

 

[Woody2Shoes]

I agree - limiters are there to reduce/limit the size of each cut and thus reduce risk of kickback or other uncontrolled movement of the workpiece. At the kind of speeds we're talking about you wouldn't want your flesh to come into contact with a cutter OR a limiter - the effects would be similar, I imagine! Of course, your body parts would probably touch both cutter AND limiter anyway (for a few milliseconds at a time...).

Cheers W2S

 

[blackrodd]

If you read this from the HSE, It answers you're question.
I've been using these machines for many years and do find the HSE website is excellent on safety practice while still getting the job done but with a good safety aspect.
A must read in my opinion!
http://www.hse.gov.uk/pubns/wis18.pdf

The limiters are partway through the text.
HTH Regards Rodders

 

[wallace]

Thanks for all that most helpfull

 

[blackrodd]

Except for fully enclosed thicknessers, Square blocks were banned years ago, as they would drag you're fingers
and hand in and keep chopping away.
The Whitehill safety block, though much better, will take very large chunks of you because the cutter is usually arranged
above the block as well as the cutter projection, and so has full access to material or fingers.
The limiters, as the term implies, limits the amount of cut each revolution can take but as someone said in an earlier
post, at 3,500 rpm that's many, many nibbles a second.
As the amount of "bite" has been limited, so has the potential to snatch or grab of a workpiece and the operator be out of control.
A very good and simple way to "damage control" in the event of contact with the business end of a spindle moulder
Regards Rodders

 

[wallace]

I nearly always use the power feed and if not I use push sticks feather boards and clamps. I've often been tempted to have a go at moulding on my planer. It has a removable plates to accept knives. The good thing is it doesn't upset the planer knives so you could take a piece of timber straight from the sawbench and plane mould in one operation.