sip table saw problem

[Pecker]

Hi all, I have the sip 10"cast iron top table saw.

When adjusting the height of the blade, during the first few seconds of cutting it drops down by several mm from the height it was set at. This is especially true if adjusting the height downwards.

Does any one have this problem? I cant really see what s causing it.
It's not a major problem as i dont often do anything where the blade has to e at a dead set height, but I would still sooner it didnt do this.
Any ideas guys?

regards
woody

 

[NeilO]

hi Pecker ,
is there a chance the rise/fall mechanism is fouling something below the table, as you state it happens when lowering the blade and the pressure from the cut is forcing it down to its true setting , not just the one set by eye/gauge??????

dont have the saw myself, but its a thought.

maybe someone with the SIP would be able to help more , or confirm my suggestion???

 

[Modernist]

It's better to always make your final adjustment upwards to take out any play in the mechanism.

 

[engineer one]

basic truism of any adjusting is to go below where you want to and then come back up. you are then taking the backlash out of the mechanism.

all screw threads have some allowance, and wear or cheaper items will have more or less wear.

not saying this is the only reason for the problem on your machine, and would suggest you check the saw blade mounting too.

however it really does sound like you are not covering the backlash problem. this is the movement between the nut and its screw as you move the nut.

for those lucky enough to buy either an LN or LV plane in particular, their instructions on adjusting the blades reminds you to loosen off past where you want to be, and then come back to it in the proper thread direction.

one area in normal life where this action gets to be a real pain is in the seat adjustment on your car. if you have manual adjustment, you will notice that the seat seems to slip if you move it back, and not then forward again. in fact often car seats just seem to move, but that's another story :roll:

paul :wink:

 

[paulm]

Hi Pecker,

I've had the same saw for a number of years now and not had the problem you mention.

Would suggest you take off one of the side panels and check the mechanism over, looking for any loose mounting bolts or similar......

Cheers, Paul.

 

[David C]

As Stated above;

all mechanisms have backlash/slop,

therefore it is essential to set all heavy tables in the up direction.

David C

 

[9fingers]

With this degree of height change, I suspect the problem is more than wear in the adjusting nut and probably endfloat in the screw thread bearings. These are often plain bearings and the endfloat controlled by a pair of lock nuts at one end or the other. Alternatively the slack is sometimes taken up by the location of the handwheel.

Study the mechanism when lifting and lowering the blade and you should be able to see what is happening and how to adjust out the worst of the problem. Lubrication should be added whilst you are at it. In time sawdust will wick out all the oil/grease there originally and this needs periodic replacement.

hth

Bob

 

[newt]

I had a similar problem on my TS in that there was so little friction in the rise and fall mech that vibration made the hand wheel turn, hence the depth of cut changed. My solution was to place a rubber O ring on the shaft between the hand wheel and the casing. The O ring was pushed up tight to the casing and held there by a small tie wrap, this then provided the necessary rotational friction, crude but it solved the problem. The saw is a PK 200. The blade height now always remains constant. By the way I descoverd this problem when cutting some tenons they always came out to thick even though I had set the height accurately. Then I sat back and watched the hand wheel rotate, but when the part that you hold moved to bottom dead centre the movement stopped. Woodwork is real fun sometimes.

 

[Pecker]

Thank you all guys, I'm mega busy for the next week, then got a week off, so it'll be a couple of weeks before I get chance to study it in depth, but I'll report back once finished!

cheers all
woody

 

[egtmcsq]

if you dont make anyheadway with any of the exelent suggestions above then there is one final very crude way to explore.i had the same problem with my sheppace 410 saw.if your rise and fall wheel is also part of your tilt an arbor you could find that there is a short piece of threaded bar directly underneath the blade simple take the blade down and rest a piece of wood on top then place a battery or something moderatly heavy on top of wood then carefully raise the blade useing the wheel if it starts to click and refuses to go up any more then its either the threaded bar or the brass nut controlling the rise an fall anyhow you;ll find out if its somethig serious hower do not place weight dirrecly over blade just use your judgement hope you find this usefu
in my case it was and i had to turn the machine upside down to attac the replacement

 

[jonny boy]

Hi, I'm almost certain that this problem is basically caused by the free play in the threaded bar of the rise and fall mechanism. I dont have this saw but my first saw which was a Kity 419 did exactly the same and the problem was solved by very lightly lubricating the area where the arbor housing raises up and down. If you have an airline, give the whole mechanism a good blow out first and you should be able to see where the problem is.
cheers,
jon