Frustrated. I’ve been doing carvings for only about a month now and I am always sanding to remove these “ridges”. I can’t figure out why this is happening. It is only leaving these slight “ridges” when the bit is moving in the X direction. I can see and slightly feel them. They are not coming out when the bit is moving in the Y axis. As you can see in the picture it is smooth (I can’t see or feel the ridges) as soon as it turns and goes from E-W to N-S movement. It does the same on the round pattern. Is it a tramming issue or just the grain? Brand new 1/4" downcut bit. Moving at 120ipm, DOC is .125" and the makita is on 3. I have done my best to tram it and over about a 10 measurement data set I have it at a difference in .02" over a 19" span in the Y axis.
I may not be experienced enough to answer that question but do you see the same pattern on your spoilboard? If you do then it might be a tramming issue. If that doesn’t help maybe turning your work 90° to check if it is the grain affecting it.
JJCal
This looks about normal to me… you are going to get ridges where the bit steps over (that’s why we all complain about sanding, the necessary evil). A tramming issue would give you deeper grooves… so I doubt that’s you issue.
I would try slowing your speeds way down (as in half of what you posted) and see how it works with the material you are using.
Looks good to me. The way I see it is there is always going to be some manual work involved. That looks like it can be solved with one pass of a fine grit. I’m sure others have perfected the process but I would be happy with that result and the minimal finishing work involved
This is assuming the stock piece was milled (jointed, planed) and as flat as can be
Thanks. The odd thing to me is that it’s only in the one direction. I will slow down my pass and see also change the orientation and see if its just grain.
If you are going back and forth (raster) you are switching between a climb cut and conventional cut. That may be why you get that pattern.
If you run your fingers along those patterns, can you feel a groove? If not, your probably good. I get those marks too, and have learned to love my orbital sander. Also, try an upcut or compression bit.
A big help to reduce this is to reduce the step over of the end mill within the pocket tool path. This helps but the amount of time it adds to the cut is probably more time than it would take to sand it!
I have used a two-step method for reducing sanding in a pocket and not increasing cut time too much. I use 2 pocket tool pants - one with a 40% step over and another with an 8% step over. Say the pocket will be .5 inch deep… I make the first pocket go to a depth of .4 and use a 40% step over. Then the second pocket tool path, I’ll cut to .5 depth but give it a .4 start depth and an 8% step over. That’s my way of creating a “finishing” tool path for the bottom of the pocket. This works well with making trays using a bowl bit. And as a bonus, V Carve can combine these two tool paths when exporting.
Nice technique. I will give that a go. The reason I find the frustrating is I am making some signs and some of the raised letters have pockets that the roughing pass goes into but my finishing bit just details the outlines and doesn’t clean up the bigger pockets or the larger pocket areas, leaving these marks.