Hello.
After some go and back calibration process, I can say it is ok. I carved a star and a circle in de middle of the table and other in an upper corner and I can say it is almost OK.
As you can see is a good zigzag… my question is why? the same thing happend in the middle of the panel. but I don see this problem in the star… may be are very short lines…
I am thinking in the sled mounting braces… may be they have some friction that i dont feel… or the carving bit to wide? (6mm)… the OSB is tricky to cut it have hard and soft places…
I am going to make more cuts with a thinner bit or over a plywood, but may be somebody had the same problem yet, and had resolved it. If this is the case… here I am
top center is a known problem area, but you say same thing happens in t he middle so I am at a loss. .What router and z axis are you using? I have never seen that particular brand before?
I tend to suspect the linkage kit. I’ve seen similar zig-zap pattern with ring kits, but not to that extreme (have to look close). the linkage kit might be sticking and then breaking loose. It might be happening up top because of the extreme angle?
Again I think you should be able to see what is happening. A video would help to see if the linkage is jumping rather than rolling.
Also, if you cut the star and circle before, there is ‘tear-out/fruzzle’ from those cuts that the sled rides and sticks on. I have a ‘hand sandblock’ that I use to go after the cuts before the sled comes around again.
the sled weight about 5 kg… and the angle about 15…
I am going to do some adjusts in the sled and run some cuts and post you a video of how it move…but tomorrow.
OK, can not wait until tomorrow, so here i am again.
The frame angle is now 20°, I change the bit for one 2 mm diameter and I cut lines of 1 mm in depth.
Here are the graphics you ask me for:
runing a line 150 mm from frame top
the result
then i run 2 verticals lines, one near the border:
the border line near the bottom
and a second one in the middle
i can said it is near perfect all the way, from top to bottom
I think is the weight, and the OSB board, tomorrow i am going to increase the sled weight and see what hapend…
OK, can not wait until tomorrow, so here i am again.
The frame angle is now 20°, I change the bit for one 2 mm diameter and I cut lines of 1 mm in depth.
that’s moving the wrong direction, try going to 7-12 degrees
I think is the weight, and the OSB board, tomorrow i am going to increase the sled weight and see what hapend…
additional weight may help, getting closer to vertical may help, try using spray
adhesive to put a layer of paper over the OSB to smooth out the OSB.
how smooth is the bottom of your sled? have you waxed it to make it slipperier?
are the edges of the sled sharp or rounded?
OK dlang, I am going to follow you, the sled is not rounded, I will go to near vertical, wax everything, etc, etc…
I saw an other problem…I have to move de motors up, and add 20 or therty cms to the bottom, because wuen the sled CG pass the bottom of the frame the top tilts few degrees … or put some weight where the router is.
I read above that the weight of the router is half the weight of the sled? is it?
you don’t need to do them all, probably rounding the edge of the sled will be the biggest win (OSB has lots of edges for the sled to catch on, so rounding it will probably make the most difference). This doesn’t need to be a precise rounding, attacking with with sandpaper is probably ‘good enough’
adding weight won’t help, the sled is deliberately bottom heavy, and when you get too close to the bottom you run into this problem
take a long, straight board, and attach it to the bottom cross member with some sort of bracket (a board with a slot in it is good enough) and move it in and out to make it match the workpiece you are cutting.
This is what you will see referred to as a ‘skirt’ in other posts
yes, the stock router is pretty heavy, about the same weight as the two bricks.
Will give less pressure on the bit. You might see increased waves. Hoping that adding weight at the bottom of the sled and balancing will do the trick.
Your home made linkage looks pretty good! I’m sure you know this but make sure they aren’t rubbing/snagging where they cross. And of course make sure they aren’t snagging on the sled. It’s hard to tell from that picture how far they are from the sled.
on monday i am going to buy some iron weights… by the moment i change one piece of the sled, i replace the one who run in the middle by a thinner iron piece as pillageTHENburn wrote. https://photos.app.goo.gl/AFHRmNhQXtW6u7Hv9
Nice!
That steel piece should do the trick nicely!
The points of friction at the pivot points are actually not a very big problem because each arm acts as a long ever. This post sort of explains why: Throwing my hat in the sled modification ring That is assuming reasonable amount of friction. Those pivot points should move freely but they don’t need to be nearly frictionless.
I would spend time feathering the edges of your sled and wax the bottom and edges. I use bees wax for slipperiness, I have used candle wax to fill voids. Sand, fill, wax.
