blade problem

[slemishwoodcrafts]

Hi,

I have a small B&Q circular saw, handheld type with a 184mm blade and a 20mm bore. I bought a new blade for it from axminster with a reducing ring because the blade bore was 30mm. However when fixed to the saw the blade wobbles really badly. Axminster have since replaced the blade and bush however the problem still persists. It works fine when the old blade is in the saw.
The bush is not as tight a fit as the one for my tablesaw, it needs a mallet to force it in, yet i can insert this reducer with my finger. Can anyone help/offer advice?

Regards,

Michael

 

[OLD]

Have a look where the large washers on the saw spindle contact the blade there may be a problem with how they are under cut so they do not give full firm grip.

 

[brianhr]

Is the reducer the same thickness as the saw blade?

 

[misterfish]

Is the reducer the same thickness as the saw blade?

Yes sounds like the reducer ring is thicker than the body of the blade. I use a reducer on my table saw which is fine, but I'm sure its thicker than the blade in my Hitachi circular saw.

Misterfish

 

[slemishwoodcrafts]

Hi,

Thanks for the replies.

Yes, i measured the bush and it is 0.5mm thicker than the blade although both are supposed to be the same. This was the same on the first blade the replacement sent by Axminster.

I tried grinding the bush down and whilst I achieved the same thickness, the wobbling still persisted!

I'm fresh out of ideas!!

Regards,

Michael

 

[Digit]

It needs to be slightly thinner than the blade so the the pressure is applied to the blade, also I would chamfer the bore on the side against the fixed face.

Roy.

 

[Travis]

It needs to be slightly thinner than the blade so the the pressure is applied to the blade, also I would chamfer the bore on the side against the fixed face

This is good advice, even if it came from-------007

Travis

 

[mtt.tr]

Can you not file about a mill of it?

 

[jasonB]

Also check what dia the flange that clamps the blade is if its not much over 30mm you will have problems.

Jason

 

[Digit]

This is good advice, even if it came from-------007

Somehow I get the feeling that I'm gonna have trouble living this down! :lol:

Roy.

 

[cutting solutions]

I would not recommend chamfering the bore at all.
Axminster are not likely to replace a blade you have altered from the original.

The saw bush should be thinner than the saw plate thickness, not the tooth thickness. it is likely the plate is about 1.6 mm so the bush should be thinner than that.
the diameter of the bush should be 30 mm. is there any "play" around the bore when the bush is fitted? is the internal diameter 20 mm? is there any "play" on the spindle?

Check the lock nut is larger than the bush. for safety the nut should be at least 10 mm bigger then the bush, though you can get away with smaller.

next check the blade is flat. actually a good quality blade will be slightly dished in the centre (I am only talking a very small amount). use a steel rule to check both sides of the blade.

If the old blade works ok there is something wrong with either the blade or the bush.

 

[Digit]

I wasn't referring to the blade bore but the bush bore as there is likely to be a small chamfer on the shaft unless it has been relieved at the corner.

Roy.

 

[Benchwayze]

The best procedure with a reducing washer is to remove it very carefully, and bin it!

I am not being sarky. I believe reducing washers are a disaster waiting to happen.

Regards
John