W750 Trouble

[Richard T]

Hello folks,
This is my first post here and I wish it were on a happier subject.
I have just recieved my much anticipated Charnwood w750 bandsaw and find that the bottom door will not close; that is to say that the key piece inside the door will not fit into the micro switch. This means that the saw will not start and nor would I want to start it with the bottom door open. I am talking (occasionally) with Darren at Charnwood but he seems to be baffled.
Has anyone else had this experience? Any thoughts would be very much apreciated.
Thanks in advance RT

 

[woodbloke]

Richard - welcome to the forum. I think Tony (one of the mods) uses a Charnwood bandsaw...might be worth a PM, though he'll be along later I guess - Rob

 

[Richard T]

Thanks Rob. Will do.
I was just reading his account of getting his w750 - he said it was quite quiet - not as quiet as mine unfortunately. I'll pm and look in later.

 

[TrimTheKing]

Can you post a picture up Richard so we can see the problem and maybe offer suggestions?

Oh, and welcome aboard

 

[Richard T]

I'll post the pictures we sent to Charnwood as soon as the brains of the operation gets home. She should be here about six.
Thanks so much for your interest fellers; I've been going (not so quietly) mad.

 

[Richard T]

This is the top microswitch, that works..

and this is the bottom one, that doesn't:

It has been really difficult to tell how the bottom differs from the top(lefthand white thing too big/wrong shape/wrong way round? ) untill we got these two pictures side by side.
However the chap at Charnwood has now seen them too and is going to send me a replacement switch on Monday morning. Although I really can't wait that long to play with it and may well have to hot-wire it.
Thanks again for your interest and help. I'll send more photos of my various doings in future now we have worked out the wonders of facebucket etc.

 

[Oldman]

This sort of safety switch requires quite accurate alignment of the key part on the door. I've not seen a pic of yours but generally they have a shape with a cut out in the center which when the door is closed the plastic parts in the switch iteslf roll round entering the cut out part of the "key" on the door.
It also doesnt take much dirt to stop the switch parts from rotating as they should.
I suggest removal of the "key" from the door and seeing if it enters the switch by hand operation when lined up with it. If it works ok like that refit and adjust till it fits.

HTH.

 

[TheTiddles]

Take the key off the door and stick it in the switch. Plug and Play!

Aidan

 

[jack55]

Hi the bottom switch seems to have more metal near the edge with the fastening screws, which appears to result in a small gap between the centre plastic striker.

Either that or my glasses need cleaning

 

[NeilO]

Richard,
I dont own the 750 personally, but is it possible the engaging tab on the door is striking high on the m/switch contact (marked in yellow) not allowing the door the close correctly?

Just a thought , as I noticed the mark or is it just a moulding imperfection?

HTH

 

[Oldman]

Again I'm guessing but it looks like the bottom switch may have already "rotated" into the locked position even though the key is no in it. I have seen this happen before when someone has been poking about trying to defeat the safety device. It still wont give a "door closed" signal to the safety controller as the key has to act on the other plastic parts at the same time.
Worth checking for if the key refuses to move the plastics when tried manually.

 

[Richard T]

The key is mounted absolutely correctly on the door and enters the mouth of the switch spot on but it can't move that left hand white plastic bit as the switch is in the closed position and is jammed there.
As I am going to change it for the new one on monday anyway, today I will take it off, take it apart and see if it can be unjammed.
Although it seems odd that it would be jammed in the first place as the bottom door arrived seperately wrapped in plastic and cardboard and can in no way be blamed for inapropriately poking it in transit. V suspicious ...

 

[newt]

They look like different switches to me, however that may not be relevant.

 

[Richard T]

Yup, they're different switches allright; one is broken. I took it apart this morning and two small broken bits of plastic fell out. It had been stuck in the "door closed" position - power on in other words.
So now I realise the importance of the health and safety issue covered by this switch. A thing designed to prevent the motor from running with the bottom door open arrived in a condition that not only made it possible to run the motor with the door open but also made it impossible to close the door. Hooray!
I have now put the wires back together with a connector block and have finally been been playing with the saw which is fantastic - even impressive with the general purp blade that came with it. I must do some looking into made-for-the-job ripping blades.

 

[MickCheese]

Definately a man after my own heart.

If it don't work take it apart.

Mick