Hi everyone
I’m just doing some test signs and my last 3 letters are not working out. What am I do that is wrong? Any help would be great. Thanks
Test cuts are on MSF
If the issue is the missing center part of the S, that is a common problem when using MDF because of how it is made. You can try lower depth of cut and slower feed rates but it is a challenging material to work with.
1 Like
I had a feeling that is what it was. What do you recommend for a fees rate. I’m using 1/8 end mill down bit? Thanks
Without knowing the specific parameters (number of flutes, RPM you’re using etc) I’d suggest start by cutting your feed rate in half and experiment from there.
1 Like
You are not doing anything wrong. That is a cool little sign!
I blame mdf.
There should be a node edit mode in your software.
What bit are you using? size - up/down cut?
From what I see it looks like you are using a down cut bit. Top is smooth bottom is rough-ish.
If you are… it may be a simple as switching to an up cut bit so the chips are not being pushed down and breaking the thin mdf pieces off. then just lightly hand sand the fuzzies off the top.
If that does not work you may need to edit in node edit mode and make the thin pieces a little thicker.
How much? depends on your bit, you can only go so far before needing a smaller bit resulting in bit changes, longer carve time, or distorted appearance 
For painted mdf I have lightly sanded the top off of mdf so thin Starbond Cyanoacrylate soaks in deeper and then cut. As long as you are not cutting deeper than the glue soaks in it keeps little details in place a bit better (sometimes…LOL)
I’m not an expert by any means, I am what I would call a novice, I have experience with Vectric Aspire and an Iconic cnc through work. I have an OF Journeyman on order and fingers crossed it’s ready for pickup Mid-July.
1 Like
@Terryjames it is a little bit the MDF fault. But also what size tool is used. The path is determined but where is can fit for the clearance.
In this image first one is using a 1/8" if you notice the little grey lines don’t fill up the letters. Then same bit 1/8" in the second row but bigger sized letters. In the third I used a 1/6" end mill and it shows the letters filled and I know it will take longer because of the size of the end mill. The last on is a 60 degree 1/2" diameter 1’4 shank and it shows taking a single pass to cut the letters.
Sometimes I have to edit the nodes to get the tool to pass and cut what I want or resize the letters. I have also used sanding sealer to harden the MDF up also.
Hope this helps.
Frank
1 Like
