Tramming - Front To Back

There are a few methods to tram your machine. Loosening some z mount bolts, using 123 blocks, tram arms, folded pieces of tin foil, are all methods that can have acceptable outcomes.
Left to right tram is relatively easy to correct. Front to back is a bit harder.

There is a unique benefit of buying a Onefinity CNC machine is that every Onefinity machine has built in front to back tramming bolts on the X axis. These allow for tilt of the z slider front to back.

There are 4 bolts on each foot (x-35 rails with the extra 3rd rail (stiffy) have 2 bolts in the feet on 2 on the stiffy but the basics are still the same).

This picture shows the location of the tramming bolts for forward to backwards motion on the front of the x axis foot.

This picture shows the location of the tramming bolts for forward to backwards motion on the back of the x axis foot.

Scenario 1: After surfacing your wasteboard, you may notice ridges showing the tilt of the router head. If the ridge is raised higher on the front side and lower on the back side, the router head is tilted back and the bit is tilted forward. To correct this, you would tighten the bolts (on both x feet) according to the green arrows and loosen the bolts with the red arrows to bring the router head forward and the bit backwards.

Scenario 2: After surfacing your wasteboard, you may notice ridges showing the tilt of the router head in the opposite direction as that of above. If the ridge raised higher on the back side and lower on the front side, the router head is tilted forward and the bit is tilted backwards. To correct this, you would tighten the bolts (on both x feet) according to the green arrows and loosen the bolts with the red arrows to bring the router head backwards and the bit forwards.

A little bit goes a very long way (sometimes were talking about a thou of an inch). After adjusting the 8 bolts (2 on front side and 2 on back side of both feet) you will run another surfacing pass. Repeat this process until you’ve reached the desired tram level.

When using this tram method, it’s important to do it at both far ends of travel, not in the center of travel.

You could spend your lifetime trying to achieve that .0001 perfection, so it is up to each user to determine their best return on investment = time spent tramming vs tramming results.

Our recommendation is to get it ‘good enough’ and cut a few projects. Then you will know if the level of tram is worth investing more time into perfecting. Most new cnc users could spend little to no time tramming and have successful cuts.

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