Morso Manual Chopper and Fletcher 5000 V-Lock Underpinner


Grumbler in Training
Sep 24, 2021
Lotus Elyse Custom Framing

Just recently bought a Morso Model F Manual Chopper alongside a Fletcher 5000 V-Lock Underpinner and was finding myself running into some issues and had some general questions.

Morso Chopper:
1. I am using the rabbet supporters that are suppose to stop the rabbet from splitting but I am still finding them busted, could this be a moulding issue or that my blades are not sharp enough?

2. What are tall tale signs that my blades are not sharp enough or becoming dull?

3. Some chops are becoming a little off, so how do I align/calibrate the blades to create straight 45 degree cuts with no gapping when joining the moulding together?

Fletcher 5000 Underpinner:
1. My frames arent joining together tightly and I was wondering if that has to do with the v-nails being used?

Thank you for any help you can provide!

Rick Granick

SPFG, Supreme Picture Framing God
Forum Donor
Resource Provider
Jun 30, 1999
Cincinnati, OH
Too many variables here to answer these questions without seeing the equipment. Use the search function here on the Grumble and you will find previous discussions of similar issues, along with some detailed possible solutions. I will say that having properly sharpened (hollow ground) blades is vital to get good results with a chopper. As to the rabbet supports, you may have them set too high. They should just barely contact the underside of the rabbet when the moulding is securely held in place against the bed and fence of the chopper. If they are any higher, the lip will crack and/or your miters will be off, causing joining issues.
:coffeedrinker2: Rick

David Waldmann

Herder of cats
Forum Donor
Featured Vendor Forum Sponsor
Feb 6, 2002
Chester, Vermont USA
Vermont Hardwoods
1. I find that the supports need to be snug against the bottom of the lip. I do this by first putting slight pressure on top of the moulding with the knives and then pulling the supports up "snugly". It takes some experience to know just how much.*
2. I would say generally the first thing you notice the knives getting dull is chipping at the very end of the miters.*
3. See the following for a description as to how we adjust the fences for a true 45° and other helpful tips: How to Cut Picture Frame Joints | Vermont Hardwoods

*my experience is exclusively with hardwoods, other material may require different methods.