If you mean the 4A then there is not a lot of difference. I own a 4A and I think the only difference was that the 4B had a few more bells & whistles in that it could do outlines off any font and came with a font extender so that it could carry more than the standard 8. I still have mine and can use it through a Cadlink fastboard using Signlab.
I started with a Signmaker III. The evolution was:
Signmaker IV added the ability to used autokerned fonts.
Signmaker IV-A add the patented stainless steel alignment pins which was a thinly veiled effort to lock out aftermarket producers of punched vinyl.
Signmaker IV-B added more power to the motherboard allowing for the introduction of plugin modules for outlining, shadowing etc.
This was all obseleted soon after with the introduction of the Sprint series. Sprint featured Gerber's version of Bezier curve data which they called Cubic Curve Routines. The Signmakers had all used linear data which looked pretty bad when produced at large sizes. In addition the Cubic Curves provided nearly double the effective speed of cutting. The Sprint also had a monitor to allow you to see what you were creating.
Pat, I don't know why you would say that. At the time (around '84/85) Gerber was leading the field. In Australia the only other signmaking computers around were some Belgium made junk called CSR (Computerized Signmaking Robots) which had big noisy clunky boxes that kept breaking down because they were about ½ price to Gerber. They had an Apple computer which allowed the type to be seen, but from memory on more than one occasion I had friends come to me for lettering because their puters were out of action for months on end. I still use my old 4A for making pounce patterns and cutting Scotchlite®.
We have the 4B, and it's been running everyday for the last 20+ years. No boat anchor here lol
Me too. Bought mine used (5 yrs. old) in 1990 and that machine still runs every day, linked to my 12 yr old 64 bit generic CPU with GA 6.21. We routinely cut 10 yd. rolls into stripes with it while the big friction fed plotter has a nervous breakdown just contemplating 350" stripes. Remember they cost 10K when they came out!? Anyway, it's too heavy for a boat anchor. If it ever dies it will deserve a Viking funeral!