I am trying hard to learn how to "stick" my own moldings with hollows and rounds.

So far I haven't had much success -- I do fine Sharpening/tuning up my old Stanley bench planes to work great, but in trying to make a couple of the old hollows and rounds I have take a decent shaving I am struggling.

I think I need to true up the soles and work harder on getting the irons perfectly aligned with the sole and then sharp. I know the theory is to use the hollow plane to true up the sole of the matching round or vice versa, but I'm struggling to take shavings in soft woods and am reluctant to try and plane the old, hard beech plane bodies.

I'm thinking it might be easier for me to start with getting the hollow working and then use that on the corresponding round. Can I glue sandpaperto a wooden dowel and use that to true the sole of the hollow?

From a geometry point of view, I isn't the curvature of all the soles the arc of a circle? If so, using a round dowel as a "truing/sanding" platform should generate the right curvature -- right?

Theoretically, shouldn't I be able to use the saying size Dowel/sandpaper to achieve a matching curvature on both the sole and plane iron?

Are replacement irons available for hollows and rounds and if so is that something I should consider?

I have made a number of wooden body planes that work well, but it seems to me the challenges involved in building a molding plane and particularly the metallurgy and grinding associated with making the iron are way over my head. Do you think the calculus of time, effort, cost of materials and probability of success in making my own molding plane is worth giving it a shot? In this case, I'm not so much interested in the building experience as I am in the final result of a working plane I can use.

I have been able to restore lots of old tools and get them working as well as anything manufactured today, however I'm beginning to think that when it comes to molding planes there is a big difference between trying to tune an old tool to work well and and the new planes being made by Matt Bickford and Old Street. If it were in my budget, I would love to get some of those new planes to see how these tools are supposed to work -- it sure looks easy in the videos!

Any advice and suggestions are much appreciated!

Thanks, Mike