I have a 1980 Delta Planer–18″x6″.  I am considering replacing original head with a helical head.  A company in Pennsylvania, Hermance, says they can make a helical head for my older planer. 

Questions

1.  Has anyone had a new helical head made for an older planer?

2.  Has anyone dealt with the company called Hermance?

3.  Are there other companies that make retrofitted helical planer heads?

4.  I live near Warrenton, N.C.  Is there anyone in my area that has an operating helical head planer that has advice or that I could visit?

Thanks    Bruce