Tab Height Lock?

Hi all, I’ve been using Easel for the past few years for prototyping. I’ve run into a problem this past week that is delaying my project. I am unable to input a custom tab height taller than the size of my material. All other functions are working.

I can see and interact with the tab height input field but the height of the tabs keeps reverting to a maximum of the material size. For example: If my material height is 2mm but I want to set my passover tab heights to 5mm it will let me input 5mm into the field but it will auto revert back to 2mm (the full cut depth height of the material/board) as soon as I click out of the field. This was not like this a few days ago when I last cut.

Why would I want the tabs to be higher than the work piece? Because I am cutting a material with edges that flex up as soon as they are cut. I need my endmill bit to clear this flex zone (3-4mm) when passing over the tabs.

This is something that I have been doing for about 2 years now and now all of a sudden (this past week) I can’t customized the tab height beyond the material height.

I’ve searched the forums and tutorials to see if anything has changed with any software updates this past week but alas here I am with no solution.

I’ve also tried selecting the “custom” labeled button in hopes of disabling any possible auto lock when using recommended settings but nothing works. The tabs keep reverting to the height of the material. Was there a tab lock feature added lately?

Yeah, this may be something that they just changed. Most people would not really “need” a tab height higher than the surface of the material.

That being said, setting the tab height for the cutout in Easel should cause the tool path to retract to the surface of the material plus a minimum offset height since the machine is not 100% accurate. In your case the tool path would send the bit right over where the surface of the material should be, possibly slightly skimming that surface due to inaccuracies in Z movement.

This leads me to gripe, once again, about a similar issue. Easel will often send the bit right over an area of a carving that has multiple depths being carved out right at where it expects that surface’s Z height to be. Since there are inaccuracies in the Z movement, this often leads to a slight mark traversing an area that has already been milled and will not be touched again.

Easel SHOULD ALWAYS traverse any area that is not to be milled again, or in your case never to be touched at all, with a minimum retract height to ensure the bit never touches the surface.


Brandon Parker

1 Like

UPDATE: Just got off the phone with Easel support and it has been confirmed that tab height IS INDEED now locked to material height.

Apparently newer users were entering values for height they did not need and issues arose…thus devs locked the tab height.

Dear Devs: If you are going to lock the tab height then atleast create an unlock option (even if we have to search for it) for those of us that are using the software in a bit more advanced way.

1 Like

Hi @RiveraRobotics,

We hear you on this, and your use case makes a lot of sense. We will explore changing the tab height limit to material thickness + safety height.


@JeffTalbot while you are at it, please look at adding at least a millimeter or two safety height for any traversal of a path over a previously milled section during the middle of a carve.


Brandon Parker

1 Like

Thanks Jeff, as far as the tab height lock issue you guys are not alone…I’ve been trying to find another CAM program that allows this without success. This is why I kept using Easel for as long as I have. It’s such an easy thing to do (you guys literally allowed this a week ago). From the info I got over the phone it seems that it was done to curtail mistakes by novice users. Understood. However, I’m thinking that a reversion to the previous allowance of an unlimited tab height and then having a caution prompt or an override tick box would be a better solution. It’s pretty easy to do (the devs definitely have the previously working code in a recent folder) and it contributes to the robustness of Easel so please send this request to the devs.

Brandon, as far as the bit hitting a previously worked on area I think what you’re hinting at is what 3D printer software calls Z-Hop. Simply, the bit/nozzle moves up a specified safety height before traversing over ANY of the work area. The unlimited tab height would be great because it allows the tabs that hold the work piece in place to remain undamaged in the case of particular materials flexing up; what you are asking for should be MANDATORY as the bit is then doing damage to the actual workpiece. I believe Z-Hop only works in conjunction with Z-Retraction (retracting 3D printer filament) in software like CURA, for example, but this should be doable as a standalone function to CNC toolpath travel.

However, I’m thinking that a reversion to the previous allowance of an unlimited tab height and then having a caution prompt or an override tick box would be a better solution

Why would this be a better solution for you? Would adding an allowance to go up to the safety height limit you in some way from doing what you want?

From a safety standpoint, we feel the hard limit is safer as warnings/prompts, etc. are easy to overlook.

Easel already aims to do this and does do it in most cases. We are aware of some situations in which it fails to do this, and we are working on addressing and improving that behavior.

@RiveraRobotics, I agree with you… I’m just saying that the tab is like a piece that is not being milled again, and Easel should retract above it instead of skimming right over it at the surface height of the material. If all non-milled or finished surfaces forced a few millimeters of retract my issue would be solved. Your issue is more difficult though, and I can see why they locked the tabs, imagine what would happen if a novice user entered 10" for the table instead of 1". Crash - Bang - Boom, there goes the limit Z limit switch with possibly other broken parts. :frowning:

Enabling hard/ soft limits, where appropriate, might solve the issue, but people will always find creative ways to break things no matter what. :smile:

@JeffTalbot thanks!! This has been an issue that I have noticed quite a bit more recently. It is very interesting to me how Easel works it out fine in some instances, but in other areas, on the same piece, it fails to provide that extra Z retraction.

Thanks for looking into the issue!


Brandon Parker

I’ll add that the safety height is configurable (under Machine > Advanced) so the combination of two should achieve the desired behavior. However, changing that will affect the retract height for fast travels when moving between cut regions.

While you can adjust the safety height as you state, this actually does not affect the two things that are being discussed. I know my safety height is good, but it is not applied in all cases/ tool paths that Easel generates.


Brandon Parker

Why would this be a better solution for you?

The caution prompt or override tick box were just suggestions if the safety height allowance for tabs was not doable. Your solution of a Tab Safety Height field is better.

Would adding an allowance to go up to the safety height limit you in some way from doing what you want?

If you add a Tab Safety Height input field in the Machine > Advanced Settings pop-up box that would solve the problem (just allow the parameter to be unlimited :))

Beyond my original use in the OP for tall tab heights is this other particular case: Lets say I’m using a 3.175mm bit (1/8in) with a 12.7mm (1/2in) cutting surface. My material is .5mm thick and I achieve the profile cut I need with one pass at .5mm per pass. I want to be able to get the most use of that bit so when I’ve destroyed that .5mm section of bit I will input a larger/deeper cutting depth in Easel so as to use the “fresh” .5mm cutting section of the bit right above where it was previously hitting the material. My bit is 3.175mm in diameter and the safety protocol for my shop using this material and bit allows for pass depths up to 1/2 the bit diameter. Note that although I’m using a soft spoil board underneath with negligible damage/stress to the bit, I am factoring the spoil board as an added .5mm with each consecutive round in order to stay within bit cutting depth safety protocol. This means that I can use this particular bit with up to 3 different cutting depths within the safe zone (same bit, same material thickness, 3 rounds of cutting). Finish one round of cutting then trick the software with deeper cutting depth and cut at .5mm deeper on the bit. Repeat once more after the second round of cuts. All within the safety protocol of my shop and materials. This allows me to use the same bit for 3 rounds. If the tab height is limited to the material thickness I can no longer do this because after the first round the bit will be .5mm lower than the previous pass but my material will be at the same Z position as always. The software is telling my machine to cut the tabs at .5mm lower than where they need to be. Since my material at the Z is only .5mm thick the tabs are being cut.

Please help me save money on bits, haha. Add the Tab Safety Height input field please.

I think you misunderstood me. What we are thinking about doing is just using the existing safety height setting under Machine / Advanced.

I am having a hard time understanding your example.

@RiveraRobotics Check out Fusion 360. Those are non-standard use cases and you’ll have much more control of the toolpaths with Fusion. The issues @BrandonR_Parker is referring to drive the avid Easel users to move to other CAD/CAM packages.

I think you misunderstood me. What we are thinking about doing is just using the existing safety height setting under Machine / Advanced.

I liked it better when I misunderstood you, haha. Currently changing that setting doesn’t affect the tabs. So you’re saying that in the future the Safety Height setting under MACHINE > ADVANCED will include the tabs also? That doesn’t make sense. It needs to be independent of this setting since tab height may need to be within/lesser than the material thickness.

It’s suuuuper simple…just add another input field titled Tab Safety Height under the regular Safety Height and watch how many users take advantage of the setting. You guys literally allowed this within the past 2 weeks so all it really takes is the input of the field and a permission code to adjust the tab height parameter. This would take less than 30 min and would be used I promise. Without this feature I can’t use Easel for my projects using this particular material so its worth it for me to even offer assistance in funding the dev time for one of your guys to get it done. That or pizza party for the team (everyone loves pizza!)

PM me if your guys are interested in the help.

Thanks Jeff!