SIP 01446 problem help required

[fluffflinger]

OK help is required

Said table saw is cutting a v in all cuts. So if you cut and place cut edges together there is a visible gap at the top of the board.

So the blade is wobbling right???

Checked with four separate blades same issue and also one from my saw at home which is the smaller brother and cuts perfectly at home but when attached to my saw at work produces the same problem.

Removed arbour, bearing seems fine. Went to local saw doctor with arbour so he could check it for me. He said it was a hair out and he skimmed it but said it was so miniscule he couldn't believe it was causing a noticeable issue.

Saw re-assembled and problem remains. I am not am engineer and other than setting up the saw, changing belts and blades and general maintenance I am a Neanderthal when it comes to engineering.

Apart from changing the bearing which has zero play in it in mine and the saw doctors opinion what bit of saw geometry is out of whack?

Any help would be welcome .

Best

Richard

 

[CHJ]

Is the blade at right angles to the saw bed?

 

[Ttrees]

Sounds like you have allready checked your table insert is flush.
Sounds like you might have had a look at the arbor flanges, and possibly gave them a lick on a surface
plate to check that they are will be in contact with the blade on the outside edges, so when arbor nut is tightened flattens out somewhat.

Have you checked the table for flatness?
Tom

 

[fluffflinger]

The blade is at 90° but it makes no difference as the cut is v shaped regardless of blade angle.

Insert is flush and the problem is the same either on the bed of the saw or if I use my crosscut sled.

I will check the arbour flange in the morning but I visually inspected when I replaced the blade and it appeared to be making contact all around. I have a granite plate and some lapping film so I will give it a touch up.

Not sure why the table being flat would cause this issue please explain???

I am truly mystified???

 

[Ttrees]

I just thought it might be worth putting in there for a possible explanation.
On an old tablesaw that I've been working on, (far from commissioning yet)
I have made up the missing rail for the sliding table, it was only when I mocked up a fence for a crosscut scenario, that the timber was rubbing on the bed so much, that it comes to a halt halfway through..
I only then looked at the flatness of the table, and its got a heavy dish in it.
Another winter project :roll:

Tom

 

[Deadeye]

Have you put a dial indicator on the arbor in situ? If that runs true, then the issue is blade or table.

If the arbour (in place, not as a separate cylinder with the saw doctor) runs true, then if you put a dial indicator on the blade is there run out?

If there's no run out in the fully assembled saw on either arbour or blade, then your table top/sled is the place to look.

 

[fluffflinger]

Have got the blade runout down to 0.02mm. As checked with a dial indicator. That is about 2 fag papers, so pretty good.

I'm sure if any of you have tried to set up a saw you realise how senative a dial indicator is. M

Biggest issue I found this morning was the flatness of the blade washer which I honed up on a surface plate. It was only contacting on the inner portion so we honed to flat and that helped get me to where I am.

Still have the same issue but alot less. Last thing to do is change the bearing in the arbour. Which is on its way to us. Although the blade is as true as we can get it under load the problem is still there and that can only be a tiny amount of play in the bearing???? There is no discernable play but maybe under load there might be?

I will update when I have changed the bearing.

The only other comment I have is that the blade washer is supposed to be a flat surface by design. Yet on the two chop saws we have the washer is machined to only allow contact on the outside portion, say 8-9mm. Is this the norm?

 

[Ttrees]

I noticed a huge wobble before I gave the arbor flanges a rub, and it was not noticeable that there was anything wrong by looking at them.
I just did enough to ensure there was contact on the outside of them, which was about 20 seconds each with some 400grit.
Presuming someone here can/has the equipment and measured their arbor flanges.
I presume they are hollowed out not just for wobble issues with regular blades, but for ones that have a blade reducing bush.

If they need to be hollowed out, have you a way of doing it?
Could the other sides of them be damaged aswell?, maybe this might be the answer if you can get away with them being flat.
You might need to be extra clean before installing a blade, for example.
At least you have a good reference now if they are chewed up or deformed by overtightening.

Tom.