Mega V Tramming question.

[jeremy]

Hey folks, I am brand new to CNC machines. I have my Mega V assembled and actually cut out a waste board with the same hole pattern as the Mega V base. So it works and it is awesome.

I am now onto the tramming part. I plan to surface the waste board and then tram the machine. My issue is that I can see just from putting a square on the base that the router already has a decent amount of forward nod (I think this is the right term, please let me know if it isn't) so that it will cut deeper toward the front of the machine. 

My question is, how do I correct this? The gantry extrusion has 4 bolts on each plate (2 of them unreachable) so I cannot loosen them to "twist" the gantry extrusion to correct this. I was initially thinking about loosening the spindle mounts and putting some thin shim material between the spindle mount and the the plate behind it but the bolts for the spindle mount are also not accessible. Can I put shim material on the inside of the spindle mount or will that not be stable?

Thanks in advance for the help!
   Jeremy

[agrpm]

I cannot speak for what others have done, nor do I have a mega V. I am the proud owner of the millright power route system. That being said, I did correct the tram on my machine by placing shim stock on the inside of the router mount between the router body and the mount. I was able to dial my machine in within .005 over a 15" swing, which I personally thought was very good. I have had no issues arise thus far from solving the issue this way and the machine cuts great! The only real difference worth pointing out between what I was able to do and how you would do it is that I have two router mounts which gave me quite a bit of freedom to "kick" the router which ever way it needed to go.

Regards,

Alex

[Derek the Admin]

I am a fan of shim stock as well. You can place a bit between the X plate and each Z rail.

[btreichel]

FYI, my local Ace hwd has sheet shim stock in Al & Brass for 4 to 7 $'s; and amazon has it for similar pricing in thin rolls.

[jeremy]

Ah, I hadn't thought about putting it behind the z rails. That would not be too difficult. And yeah, I am pretty sure I've seen shim material at the ACE here in town. Thanks for the suggestions everyone!

[garymkrieg]

You can also get a feeler gauge at Harbor Freight for $5 that you could cannibalize.

Gary

[btreichel]

Feb 21, 2020 17:28:14 GMT garymkrieg said:

You can also get a feeler gauge at Harbor Freight for $5 that you could cannibalize.

Gary

Yep, but that's 30 miles one way, and I could never get out of there with only a single item!

[Bruce]

I used some paper folded into 1/4" x 4" strips and shimmed up the bottom of the router mount. It is a pain having to pull the Z axis off to get to the back mounting screws, shim it, and then check tram and do it all again... but you'll only have to do it once. And you'll thank yourself when it's done.

[jvenn]

Bruce, I followed your suggestion and shimmed the bottom of the router mount with paper. It seems to be square to the platform now. If necessary, I will shim between the X plate and the Z rails to fine tune things.