Thread: Heads Up to Hammer K3 Owners

Originally Posted by Mobyturns

Not true!

It may be partially true if and only if a test cut is made to verify the length and only if the toe of the stop is closer to the saw blade and the measure has been calibrated with that particular flip stop.

That was the context, using two different flip stops that had variations in slope would indeed nullify the assertion and I did not think of that at the time. I have three of them but the fence always has at least two mounted and used. Good catch Moby, we sometimes miss the obvious.

Following along with Chris I also checked my K3 Flip stop.

Unfortunately mine was very bad in that there was over 1.5mm gap at the bottom. This is the worst situation with the flip stop leaning towards the blade.

Tried to find out the cause of the problem. First I mounted the paddle on the mill and machined both sides flat and parallel. Mt paddle was not even flat. Very poor quality. Then I mounted the attachment block on the mill and machined the paddle end square to the fence in both directions.

Reassambling and checking showed no improvement even though the paddle end of the mounting block was square to the front and top of the fence. I then mounted a dial micrometer on the sliding table and determined that the top edge of the paddle mounting shaft was about 0.08 higher over about 12mm, at the end away from the blade, hence the paddle was tipped over with the top closer to the blade than the bottom.

How to fix it. Not easy. The best option would be to machine approx 1mm off the bottom of the mounting block at the paddle end so that the block now slopes away from the blade. However the cursor is mounted under here and gets it the way.

I decided to take the bodgy but easy way and machine 1.5mm off the top front of the paddle tapering to nothing off at the bottom. A bit of gentle sanding with a sheet of 800 G emery on a very flat surface means I now have a very close to vertical paddle front .
Ron

My flipstops are presently being worked on and I hope to have more news this week. I have to say that Felder have been very good over the whole thing and gave me a few flipstops from their stock to have a play with and they asked me to show them the result after they are fixed. Stefan at Felder has promised to take it up with the factory and sort the matter out once and for all. I checked all the Felder machines in their show rooms and they are all OK. Thanks for the feed back Ron and good to see you fixed yours. I am surpised that other owners have not commented for either good or bad.

Were you able to check if its an error in the machining or the mechanism itself? Does the Felder or Format4 saws have a completely different mechanism which ensures the flip stops are square?

I would imagine it would super annoying for owners with digital read out or motorised flip stops if they were inaccurate

Hi qwertyu
At least in my case the pivot shaft for the paddle was not drilled and tapped exactly square to the end of the paddle support bracket. I was able to measure at least 0.08 mm rise in the shaft over approx 12mm length of the shaft. This resulted in the paddle being tilted towards the blade by about 1.5 mm at the top. Ie there was a 1.5mm gap at the bottom between a square on the slider and the vertical face of the paddle. As far as I could measure my shaft was parallel to the fence axis in the horizontal axis so that the paddle was square out from the front of the fence.
Ron

In the cases presented by Chris and myself, a quick fix for the issue is simply to add a small projection along the lower face of the stop ...



This ensures that any tilt is at the bottom of the flip stop. Also that the height is low, reducing any error to negligible.

A better fix would be to re-machine the underside of the flip stop slide, but that proved to no be possible with mine. I added a shim (as photographed earlier), and this has trued up the flip stop.

Regards from Perth

Derek

Derek, what was the reason the underside of the stop block could not be machined? Ron has found as I presumed that the shaft has been pressed in out of parallel with the underside of the block. There are obviously three ways to fix that, machine the under face of the block or pull the pin out (it screws in) and fix the bore it is to be parallel or machine the face of the stop as Ron has done. I have just measured the top to bottom face on the fence and it is as near as dammit the same end to end which means the pivot hole is not parallel with the underside of the stop. I would prefer to fix the problem and not work around it but then I have access to ways of doing that. In theory it is an easy fix, pull out the pivot and screw in a bolt with an adhesive and then drill it correctly. I wouldn't even bother tapping the new hole, just glue the pivot in with Sikaflex or Loctite or cross drill it and use a roll pin.

Chris

I will have a look at the pivot hole, but in my case the angling appears to have run in the other direction. I cannot file away more material as the perspex on the underside of the top of the stop bottoms out on the ruler. Two layers of electrical tape, and it is perfectly square. I will likely just add a layer of epoxy, which will become a permanent fix.



Regards from Perth

Derek

In talking to my B in L he has found that each stop has to be assessed and dealt with on an individual basis because they all have unique problems. I have two which look like a production change and are identical and each slopes the opposite way to each other. These ones look like they are powder coated where my original ones are not finished at all. I looked at the plastic cursor thingy and that was the reason I chose not to machine the bottom face.

I received three of the flip stops back today all fixed and square. My B in L removed the pivot bolts and was able to fix two by machining the face of the block that the stop abuts to on the sliding block. The other he fixed by machining the face and adding a thin spacer and if it measures the same as the faced ones all is good. I haven't had a chance to measure them and it is something I didn't mention because I did not think they would be fixed in that manner. The dimension from the cursor line to the flip stop face must be the same if using multiple stops on one fence as I do. I might get to that tomorrow provided my day goes as planned.

Good point Chris regarding multiple stops on the same cross cut fence. I also had not thought about this problem.The hairline cursor is not easily adjustable so what are you going to do if they are not all the same dimension.
With three or four stops you might get lucky and find two that match.
The cursor is not adjustable so there doesn’t appear to be an easy fix.
Cheers
Ron

I checked mine, it was only .6mm out and 3 weeks old.

I found that there is some adjustment in the cast arm, you just need to use a little force, although it is not .3mm

Although it isn't ideal and it should be square from day one.

Im starting to think that each time you slide stock on to the stop with any weight, it causes the bottom to move.

as the force i used to square up the flip wasn't much on my flip.

i'm awaiting to hear back about a true square replacement.

Originally Posted by ronboult

Good point Chris regarding multiple stops on the same cross cut fence. I also had not thought about this problem.The hairline cursor is not easily adjustable so what are you going to do if they are not all the same dimension.
With three or four stops you might get lucky and find two that match.
The cursor is not adjustable so there doesn’t appear to be an easy fix.
Cheers
Ron

I found mine are not the same measurement from cursor line to flipstop, they possibly were but after machining that went out the window. Ebay is sometimes helpful and I found some stainless steel 10mm x .2mm shim washers to set the distance or at least very close.

Bryn, If they can't find one and if the heel is closer to the blade than the top of the stop then it will make no difference. The problem is if you are using two stops the slope of the stop has to be the same in both. The wood being cut then contacts the stop at the heel no matter how high it is. In fact I would not be surprised if that was the way it was originally designed because then the contact is minimal and no debris or a rough finish on the wood will not interfere with the measurement.

Originally Posted by Chris Parks

Bryn, If they can't find one and if the heel is closer to the blade than the top of the stop then it will make no difference. The problem is if you are using two stops the slope of the stop has to be the same in both. The wood being cut then contacts the stop at the heel no matter how high it is. In fact I would not be surprised if that was the way it was originally designed because then the contact is minimal and no debris or a rough finish on the wood will not interfere with the measurement.

If the stop is at an angle when you switch the fence to the other end of the slider and flip the stop it will then contact at the top of the timber and the scale will be totally wrong.

I think that your only real solution is to drill and tap each stop near the bottom and top (so you can reverse it) and fit an adjustable stop in the form of a screw and move the flipper away from the block with a thick washer. The screw will then take up the thickness of the washer and enable you to calibrate all the stops to be identical.