Upgrading to Mach4, have some questions about custom things added

I have had my pro 4896 since late 2017. It has done well enough for me but, mach3 sucks and I am thinking of using mach4 now.
I have created my own rotary axis and it works great. However, the fusion post processor has not been updated since 2019 on the avid site and the options available show only wrapping the y or x axis around the a. My current setup has an a axis and I can use my y axis while using the a. Is the avid post only capable of locking my y axis in place to use the a axis? I want to be able to machine whatever needs to be machined during the whole operation and not limit my movements. Pocketing with actual 4 axis available is much better than the garbage output you get when you have to access a pocket from an angle. they are never correct. I can see that being ok for art carvings or whatever.

Besides the rotary setup, I have also been using an m6 tool change setup in mach3 that allows me to have a permanent touch plate and my avid touchplate. Touch off of the material with the avid touchplate at the beginning and it moves the tool to the permanent to get the difference. Then when M6 comes in, the tool moves to the tool change position, allows the change and then moves to the permanent touch position and touches to get the correct length based off of the original touch position.

Many times during machining a project you will lose the material that you started the job with. If you change tools, how can you get the correct length from the same position if it no longer exists? I am sure it is possible to create a new m6 script to account for this but, this is a huge feature that I will lose if upgrading to mach4 and I would have to learn the lua language enough to build it back out unless someone here has that capability already. It is a huge reason I have not upgraded.

My 3rd concern is that I may just be waiting my money on the mach4 license. It is hard to get new information about problems that I have had with my machine because it seems most are now using mach4. I purchased my machine before avid came about and got all the attention it has now.

On that point, I cannot get my circles to be circles and was hoping that mach4 might help in that. I have done an insane amount of troubleshooting movement and verified that everything is square and trammed. My distances are almost perfect when measuring using 12" digital calipers over and over in different areas of the machine and in diagonal tests. Yet, every circle comes out slightly oval at any size and the measured differences around those circles is pretty much the same at all sizes. This means that the smaller the circles are, the more pronounced it seems. a 1/2 inch circle would vary between .5 and .48. I was hoping that the mach4 program would be capable of running circles better than mach3. I am willing to pay $200 for circles that are circles. I have spent so many hours trying to fix this issue and nothing makes sense to me any longer.

Anyway, if anyone knows if the rotary setup is only capable of wrapping an axis and not being an independent a axis, M6 permanent touch plate and better ability to create legit circles, please respond.

It is an independent axis. You can also get true 4 axis machining with F360 on a pay-by-use model which is very affordable.

Thank you. I do have that capability now but was worried by the post processor naming that says wrapped y or x axis. The clarification is great to hear.

Yeah, that is true. I just created my own from the default AvidCNC and added my own 4th axis. I think the reason (pure speculation) is that most CAM doesn’t actually do true 4th axis so they made it for “the average joe.” In F360 you use 5 axis but set the constraints on the 5th. Then you start getting that A axis and X axis motion together (if that is how you have it set up).

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Thinking through it at first was harder than I expected. Once I played around enough I learned how to deal with the motion. it is amazing what is possible with an added axis. I use zbrush to import stock shapes generated in fusion and sculpt organically over the stock. import back into fusion and I cut accurate pockets as well as artsy sculpting and know it will fit what I am going after.

This is some trim I made for my garden window in my kitchen that used the method and when I installed it, it fit perfectly into the recesses that I measured. The vines are wrapped around the flat areas and could not have been done using wrapped mode. I tried, it was terrible and a waste of wood.