Neat jig.
Firstly, how many boards has the saw cut now, sharpness is a possible issue as is lack of kerf making the cuttings jam up the saw.
Most of the saws like the one pictured as supplied are not terribly sharp.
Do you wax the blade? That sometimes helps. I use candle wax.
I have moved to a small table saw for slotting but still need a hand saw after radiusing.

I was going to suggest wax too but usually when I notice that my fret saw needs some wax to help it along it means it needs to be sharpened too. But i have never used Richlite so I can't say for sure. But I would at least try the wax. Like Colin I use a candle, bust bite the saw into the candle to collect some wax.

You mean besides Gibson?

Just a thought, could it be the possible run of the saw through the bearings squeezing the kerf? That would reduce the life of the saw.

I think Fred O. has it right, "My verdict on Richlite is that it machines and finishes extremely well - hard as stone and smooth as silk. However, this is definitely a power tool kind of material."

I've used Richlite for fretboards and bridges on my last 3 or 4 builds, and I'll continue, but only because I can do the bulk of the machining using a bandsaw and CNC router. It's very hard. It cuts very cleanly and machines beautifully, almost like metal, but hand work is a challenge. It does seem to hold frets well.

What I would get is a Japanese saw that uses .010" blade body with the teeth set to .020".............................................

Fred O. asked if I "need to use glue with the frets or do they hold without it?"

All the fretboards I've built, Richlite or not, have been bound. I've not used any glue on the frets I've installed in Richlite and have not seen any looseness, either when shaping the fret ends or, later, during use of the guitar. I have, however, found it necessary to use fret stock with a wider-than-typical tang but that's because I cut my fret slots using a 0.6mm end-mill on my CNC and the resulting slot is a bit wide for "standard" fretwire. (I use FW75 fretwire from LMI which they list as being 0.048" barb-tip-to-barb-tip.) With this combination, I find that pressing frets into Richlite requires more force than pressing them into natural wood, so I bought a 1 ton manual press from Harbor Freight and drilled the end of the toothed pressure bar to accept the shaft of the fret press that I'd previously used in my drill press. (I hope this makes sense.)

As an aside, I've noticed that Richlite blanks (fretboard and bridge) are a bit pricy from luthier suppliers. The Cutting Board Company (cuttingboardcompany.com) sells ¼" and ½" thick Richlite cutting boards in custom sizes for attractive prices. (I have no connection with The Cutting Board Company other than as a customer.)

When I first tried cutting fret slots using a 0.6mm end mill in my CNC, the end mill broke off after about the third fret slot. To deal with that, I reduced the cutting speed to 4 mm/sec. with a 0.5mm path depth at 27,000 rpm to cut a 0.15" deep slot and shortened the end mill from 6mm to 3mm -- I did that by just clipping off the end mill with a diagonal cutter -- I thought that might cause a problem. It did not. I've now cut about 100 fret slots with the same 3mm end mill.