Welding a severed bridge

In rarer cases, the parts will already be in full contact after having been cut, and you might be in favour of welding the parts together directly, although we do not recommend this. The penetration depth of the weld will most likely not be sufficient for a reliably stable connection, or you will have to work with such high welding parameters that distortion of the bridge can hardly be avoided.

In this case, even if this may seem awkward at first glance, we recommend grinding the joint in a circular V-shape to achieve a situation similar to the schematic diagram above.

If the two parts have a larger gap between them, a contact point must first be applied from both sides using a suitable welding wire as explained in the article Applying welding wire (Attention: CTE topic). This technique should also be used to achieve an initial situation as shown in the illustration above.

If the parts are now touching each other, we recommend first applying a temporary fixation, e.g. in the form of an old sprue or an old piece of work made from the same alloy. This will be removed again at the end of the welding process.

Two welding spots per segment with low welding parameters are completely sufficient for this fixation.

This counteracts possible warping and keeps the parts in the correct position.

A first connection welding spot can now be set centrally in order to then successively weld the connector
with welding wire. It is advisable to always place the first welding points diagonally opposite each other according to the wheel nut principle in order to strategically compensate for any stresses that may occur.

The bridge can be removed from the model at any time for welding or for being checked for correct fit on the model.

At the start of welding with the X-seam situation, the welding geometry , which was designed precisely for this situation, is well suited.

The contact point at the deepest point of the connector is best reached with a freshly sharpened electrode, with a blunt electrode it is difficult or impossible.

Later, to complete the desired contour, you can switch to the welding geometry to apply welding wire.

At the end of welding, the auxiliary structure can be easily removed and finished with the rest of the work.

Note: If the restoration is to be veneered with ceramics at a later stage, the area should always be ground over with a carbide bur if the electrode had been accidentally welded on in order to prevent the inclusion of tungsten particles and subsequent chipping of the ceramic.