Issue when I add a FixedHinge to an object

Hi All.
To give some detail first: Unity version 2018.3.9f1. I am having a very strange issue with an object (hammer (2 pieces mallet (parent object) and handle (child to mallet)) with rigidbody on both parts) that I can pickup (parent to player) and swing to break other objects into pieces. Of course there is gravity and kinematic required to be true to carry hammer. So this works well but I had an initial issue that when I dropped the hammer (unparent from player) object it would fall as expected to the ground; however the handle would break away from mallet object?

Searching around I saw in the help a 'FixedHinge' component that I added to mallet object and then 'connected body' is the handle... this solved the breaking apart issue when dropped; however if I do this pickup and drop multiple times the entire hammer object is randomly scaling to an enormous size each time I pickup and then drop. I did this 4 times to see if it would stop and finally the object was so HUGE it fell through the floor and out of site. If I remove the 'FixedHinge' I do not have this issue.

Any thoughts or is the a defect on the 'FixedHinge' component?

TIA!
Cheers!
Rick...