Wadkin Table Saw Brake

[woodchip]

Hi Guys,

Anyone know the approx cost of fitting a DC brake to a Wadkin AGS10?

Any links to appropriate companies?

Ta

 

[Richard Findley]

Hi Woodchip,

Do a quick Google for industrial woodworking machinery suppliers and you should find one in your area, or you could contact Wadkin, see if they could point you in the right direction.

If I remember when my old company had all it's breaks fitted when the laws came in, they ranged from about £150 on the crosscut to over £300 on the old P/T :shock: :shock: :shock: I don't remember how much the T/S was though.

HTH

Richard

 

[9fingers]

Apologies for a slight thread hijack!

Are DC brakes mandated by HSE rules or will they accept any method of braking that achieves less than 10 seconds to standstill?

I have a few braking enquiries following my write-up on running 3 phase motors on single phase supplies and so wonder if HSE will accept the programmable ramp down that inverters usually offer as well as the ones that offer a braking function as well.

I'm also interested to follow the DC brake route to conclusion and then possibly add a braking section to my write up as the next issue.

TIA

Bob with humble apologies in advance the Woodchip

 

[Steve (Correze)]

Apologies for a slight thread hijack!

Are DC brakes mandated by HSE rules or will they accept any method of braking that achieves less than 10 seconds to standstill?

I have a few braking enquiries following my write-up on running 3 phase motors on single phase supplies and so wonder if HSE will accept the programmable ramp down that inverters usually offer as well as the ones that offer a braking function as well.

I'm also interested to follow the DC brake route to conclusion and then possibly add a braking section to my write up as the next issue.

TIA

Bob with humble apologies in advance the Woodchip

Not sure how it fits with the UK legislation, but my SICAR has an electromagnetically actuated mechanical brake and is approved to current French standards. Certainly stops in well under 10 seconds.

Certainly an interesting alternative to DC injection brakes and has the advantage of operating in a power-failure scenario, which as far as I'm aware most electronic brakes don't.

Just need to remember to have the power turned on and the overrides engaged if you need to rotate a tool by hand, setting the planer blades for example.

 

[FatFreddysCat]

Are DC brakes mandated by HSE rules or will they accept any method of braking that achieves less than 10 seconds to standstill?

No. If they were SCM would be in trouble with some of their Minimax range which appear to brake by dint of the amount of tension on the drive belts. The larger saw manufacturers often opt for a mechanically operated brake which defaults to on and is held off only whilst there is power available

(I) wonder if HSE will accept the programmable ramp down that inverters usually offer as well as the ones that offer a braking function as well.

I doubt it unless the braking function is a "default condition" which will operate regardless when the eStop is hit.

 

[SVB]

I have no direct knowledge here just reading the thread but presumably the 10sec rule would still need to apply in the event of a power cut???

In that case, if the run-down was a software driven function its functionality would be lost and therefore non-compliant?

As I say, know direct knowledge just a thought.

S

 

[9fingers]

Apologies for a slight thread hijack!

Are DC brakes mandated by HSE rules or will they accept any method of braking that achieves less than 10 seconds to standstill?

I have a few braking enquiries following my write-up on running 3 phase motors on single phase supplies and so wonder if HSE will accept the programmable ramp down that inverters usually offer as well as the ones that offer a braking function as well.

I'm also interested to follow the DC brake route to conclusion and then possibly add a braking section to my write up as the next issue.

TIA

Bob with humble apologies in advance the Woodchip

Not sure how it fits with the UK legislation, but my SICAR has an electromagnetically actuated mechanical brake and is approved to current French standards. Certainly stops in well under 10 seconds.

Certainly an interesting alternative to DC injection brakes and has the advantage of operating in a power-failure scenario, which as far as I'm aware most electronic brakes don't.

Just need to remember to have the power turned on and the overrides engaged if you need to rotate a tool by hand, setting the planer blades for example.

There is absolutely no way I'd be adjusting planer blades with the power on, interlocks/overrides or not.
Just one more way in which the French seem a little mad :lol:
Oops I'd better withdraw that as I am currently a guest in their country
Bob

 

[Steve (Correze)]

There is absolutely no way I'd be adjusting planer blades with the power on, interlocks/overrides or not.
Just one more way in which the French seem a little mad :lol:
Oops I'd better withdraw that as I am currently a guest in their country
Bob

I turn it off again after I've rotated the block to the correct position, not that trusting of French wiring

Having said that, electric motors are less likely to randomly start on their own than CNC machines and I spend plenty of time behind and inside those each day. Had a few "brown trousers" moments... always have an escape route in mind and don't be afraid to jump if you think it's about to move.


I might investigate to see if it's possible to power the brake circuit separately on the SICAR, not really started to investigate the innards of the thing yet.


I'm not French, I just live there

 

[9fingers]

Small world Steve! I passed within 5km of Correze (D1089) last Monday on the way to Brive where we stopped for lunch.

Bob

 

[Richard Findley]

Hi all,

From my experience of updating our old factory, the P/T, T/S and cross cut saw all needed new elctronic braking. The B/S had a foot pedal break that stopped it within the time and so this was acceptable. The belt sander only needs breaking if an engineer type person deems it necessary and the LS Router had a hand break but apparently there is (was) no other type of break commercially available for them.

All of the electronic brakes are useless if the power is cut at the isolator and so I would assume in the case of a power cut.

Hope this is of interest,

Cheers,

Richard

 

[9fingers]

Hi all,

From my experience of updating our old factory, the P/T, T/S and cross cut saw all needed new elctronic braking. The B/S had a foot pedal break that stopped it within the time and so this was acceptable. The belt sander only needs breaking if an engineer type person deems it necessary and the LS Router had a hand break but apparently there is (was) no other type of break commercially available for them.

All of the electronic brakes are useless if the power is cut at the isolator and so I would assume in the case of a power cut.

Hope this is of interest,

Cheers,

Richard

Thanks Richard,

I assume from a safety assessment point of view that mains failure would be covered by 'dual fault' ie in the event of an accident, it would be deemed to be caused operator error plus loss of power.

DO you know if the electronic brakes fitted were DC injection or inverters.
I could imagine in the early days of HSAW/HSE that DC brakes would have been cheaper as a known technology whereas inverters were in their infancy and very expensive.

Nowadays inverters are much cheaper in real terms and offer other advantages such as soft start and variable speed (if needed) as well as replacing the DOL starter so could well be a preferred solution assuming HSE accept them.

It would be usual practice for regulation to be written in terms of 'what' has to be achieved rather than 'how' it has to be done. So maybe inverters are accepted but I'm still seeking confirmation of this.

Bob

 

[misterfish]

Do you actually need braking. My Wadkin 10BRT (basically an AGS10 with sliding table) takes well under 10 seconds for the blade to come to rest. Even with a full stacked d*do set (which is heavy and increases the inertia involved) it only increases to about 14 seconds - and you are not permitted to use these in a commercial environment.

Misterfish

 

[Richard Findley]

Hi Bob,

I must admit that I'm no expert on electrics. I think they are DC, as they are essentially a switch box fitted to the body of the machine and these have the electics in them to control and adjust the speed of the braking.

This picture of my table saw shows the switch box/brake (this is the same saw I talk about in my earlier post) The machine is 3 phase, no sure if that makes a difference?

I don't know about the other type of brake but as long as it stops it in time I can't see a problem. Best to check with someone that knows though!!

Cheers,

Richard

 

[9fingers]

Thanks Richard,

When I get back from holiday, I'll try and find a definitive answer re HSE.

The DC units I have seen in the past were on 3 phase machines and were fitted between the DOL starter and the motor.
The Brake unit simply passed the 3 phase power straight through to run the motor and to brake the motor, the 3 phase was disconnected and DC injected between 1 pair of motor leads for a few seconds - adjustable for machines with differing rotating mass - heavier ones needing more braking.

Bob

 

[woodchip]

Do you actually need braking. My Wadkin 10BRT (basically an AGS10 with sliding table) takes well under 10 seconds for the blade to come to rest. Even with a full stacked d*do set (which is heavy and increases the inertia involved) it only increases to about 14 seconds - and you are not permitted to use these in a commercial environment.

Misterfish

I timed it today at about 15 hippopotamuses.

 

[katellwood]

On placing a single phase 3hp motor on my 10ags (motor supplied by Axminster) the machine stops in well under 10 seconds even with a dado head fitted

 

[FatFreddysCat]

Do you actually need braking. My Wadkin 10BRT (basically an AGS10 with sliding table) takes well under 10 seconds for the blade to come to rest. Even with a full stacked d*do set (which is heavy and increases the inertia involved) it only increases to about 14 seconds - and you are not permitted to use these in a commercial environment.

The reason that the EU made braking a requirement was because of the high incidence of run-down accidents on woodworking machines - where the operator powered-down the machine, forgot that the cutters were still spinning and then opened the guards to make an adjustment and bye bye fingers, etc. This frequently occurred on single-end tenoners where the heads are so big they'll spin away merrily for up to 20 minutes if unbraked. Not unknown with other machine such as spindle moulders, rip saws and radial arm saws. The change in regs has apparently reduced accident levels markedly, so no bad thing.

As to the time it takes for the run down to occur that depends in the main on the load being carried and the speed at which it is turning when braking commences. I've fitted a few DC injection brakes and setting up spindle moulders where the load/speed combinations vary tremendously (because the weight/diameter of blocks is very variable) can be a real problem unless the DC injection braking system incorporates a motion sensor on the tool drive shaft and the necessary logic to sense that the tool is still spinning and keeps braking (or ceases if the machine has come to a halt).

For the record dado heads and trenching heads are not illegal in a commercial shop - it is their use without adequate guarding and on machines without locking pins and/or locking nuts to secure against braking forces which is illegal. In a trade establishment if you have an accident and you haven't got the guarding/braking then your insurance is invalidated. Same applies to self-employed working alone. In any case housing joints, or for those who insist on using that American term "dados" (which to a British joiner means a chair rail), aren't used that much in commercial work these days because they weaken the structure in MDF/chipboard and in any case we've found many faster ways to achieve the same effect more safely (e.g. biscuits, dowels, Dominos, carcass screws, etc)

 

[BradNaylor]

Apologies for a slight thread hijack!

Are DC brakes mandated by HSE rules or will they accept any method of braking that achieves less than 10 seconds to standstill?

As far as I know so long as the machine stops running within 10 seconds it complies.

The stopping time on my SCM panel saw was brought within ten seconds simply by tightening the drive belt slightly.

Likewise with my old Wadkin spindle moulder. If your machine only takes slightly longer than this to stop anyway it is well worth a try before springing for an expensive DC brake.

Brad