Adventures with Kity and a question

[chipchaser]

Hi all,

I recently bought an old but I thought good Kity 617 table saw, the one with a tilting table which looks like this:

I needed something better than my old Draper 10” saw which has a tilting arbor but is very wobbly. I made a sled for the Draper but found the pressed steel trunnion carrying the arbor was very flexible making it difficult to get a smooth straight cut even with the sled.

When I collected the Kity I noted the blade wobbled a fair bit but, as the bearings felt and sounded ok, optimistically put this down to a poor blade. However, once at home I tried a few blades and found they all had a similar amount of run-out averaging about 0.5mm. With the blade off I measured the arbor face run-out at the perimeter as 0.15mm (0.0059”) twice the figure recommended in the Taunton book “Care and Repair of Shop Machines”. I wasn’t feeling too happy at this point, couldn’t get my dial gauge into the machine to measure the shaft run-out, so imagined the worst - a bent shaft.

Having acquired a dial test indicator I was relieved to find the shaft ok with only 0.0005” eccentricity, picture below:

I removed the arbor which was a sliding fit on the shaft and key. I was lazy and rather than make the trip to the garage for a 3 legged puller levered it off with a screwdriver. I shall be more careful next time as this made some of the nicks visible around the edge in this photo:

I wondered why there were sawdust deposits on the back of the arbor but the reason became evident when I mounted the arbor in my lathe. I wanted to measure the back face run-out but lacking a suitable shaft to mount it on in the lathe gripped it in the chuck as shown below:

I had checked that the chuck face was running reasonably true (clocked <0.01mm the smallest increment on the dial gauge) so on the assumption that the shaft and arbor face were at 90 degrees clocked the back face of the arbor. The pencil numbers are hundredths of a millimetre. I decided to skim the back face which revealed the dent visible as the dull grey area at the bottom of the above picture. Having skimmed the face a bit more to make it flat and lightly cleaned up the nicked edges I checked front and back faces were parallel and refitted the arbor. I was relieved to find the run-out now measured 0.07mm ( 0.0028”). Wobble near the blade perimeter is now 0.18mm so I am pleased with my amateur fettling.

I do have the Kity floor stand but don’t have any floor space left so put it on the bench. I need to build a shallow box for it to sit on to allow me to connect the chip extractor. The only criticism I have is that the guard is very small and only covers the top of the blade. I really like the transparent plastic guard on the old Draper which wraps around the blade.

The saw makes nice straight and smooth cuts but I have a question:

Do you think that it is possible to saw cut 45 degree mitres on the ends of small box sides accurately enough to assemble without further work on a shooting board or am I over optimistic? I would expect to make a little jig or sled to slide in the Kity Tee slots to hold the timber at the correct angles.

I do have a router shooting board made as shown in Robert Wearing’s book “The Resourceful Wood Worker”

I used the flattest board I could find to hand, which as you can see is water resistant flooring grade chipboard, with Beech for the wearing faces. Although scruffy it works well but I forgot that I would need to cut two complimentary angles for each corner and only squared one side to the edge so will probably make a better one with both sides square. I am assuming that the top and bottom edges of my box side may not be exactly parallel. If they were I could just flip it around and use the same side of the shooting board. Ah, another little jig to make but its freezing in the workshop!

I look forward to any advice on mitres from the saw.

Regards

Graham

 

[StevieB]

Nice fettling! I would say you are being over optimistic in expecting to take a mitre straight from the table saw without shooting it first. Even with a good quality Freud blade or similar the cut will be rough compared to a plane. The only exception would be if you were veneering over the box or outting in a corner post (I forget the technical term!) by routing a channel down the edge of the mitre, but even then the joint would be stronger with planed faces.

Steve.

 

[wizer]

Graham. On my brand new Jet Super saw, I can't get absolutely perfect mitres for boxes. I'm in desperate need of a good shooting board. I really don't like the idea of a tilting table. A good shooting board seems to be an essential tool for mitres, IMHO.

 

[Nick Gibbs]

I think mitres are the most difficult of all joints to cut well. It can be done straight off a tablesaw, with a many-toothed blade. One of the key problems, I think, is getting the mitre slide working exactly parallel to the blade, without the workpiece touching the 'rear' teeth. In principle, though, a fine blade should cut mitres good enough to join straight off the saw, indeed I've butt-jointed boards off a tablesaw for making table tops. It's setting it all up perfectly, and having no wow and flutter that's the challenge, and that will always stretch cheaper, smaller saws. But you'd be amazed what a good blade will do.

Nick

 

[9fingers]

When buying blade for this saw, you will need to buy 15mm bore ones or do as I have make an adaptor to centralise 16mm- 5/8" blades.

Nice to see you have metal working facilities too as I have.

One modification I have made is to replace the driving flange with an adaptor to take a 30mm dado blade set. I've done lots of work with this set up though now the kity is largely disused in favour of my Xcaliber tilting arbour TS.
I hated the Kity tilting table with a passion!!! It gets in the way of the rest of the machine as I have it as part of a CK26 Combo.

Bob

 

[chipchaser]

Thank you all for your comments which are very helpful. I found it difficult to achieve the standard I wanted and I feel better knowing that cutting mitres, or bevels, is difficult for others too.

Nick, I understand what you mean about touching the rear teeth and wobble on the blade. The Draper saw tilting blade structure was very flexible. I made a sled with very close fitting runners and an adjustable 90 degree fence. Even using this sled, pushing the work into the blade moved it backwards and off line but as the front teeth exited the cut the blade wanted to move back making it impossible to get a smooth cut.

I bought the Kity because of its compact size and because I reckoned that I had a better chance of finding a solid and hence accurate saw with a tilting table than one with a tilting arbor within my budget. Although the blade has no name on it I think it is fairly good as it makes a very smooth cut with an almost polished surface. The first picture below shows a cut without any blade marking visible to the naked eye. The second shows the other end with some shallow tooth marks:

I will make a sled for the Kity and see if I can get a consistently good bevel cut with the workpiece held securely. I don’t know whether the Kity Tee section to fit the table slots is available but if not perhaps I can make some. I’ll let you know how it goes but it won’t be for a while as I must do some “proper” work.

Regards

Graham