Grinding and sharpening some hollows and rounds

[Thomas Crawford]

Finally got a (near) half set of hollows and rounds. Got the irons de-rusted and some of them need a grinding due to a crummy job by the previous owner.

I was thinking of the DMT Diamond wave for honing: https://toolsforworkingwood.com/store/item/MS-WV.XX

What are my options for grinding? Particularly for the hollows. They are all skewed if that makes a difference.

450619

[Tom M King]

They're probably soft enough that a file will work for shaping. For honing things like that, if I don't have the right slipstone, I use twist drill bit shanks wrapped with various abrasive films. The aluminum oxide sheets that LV sells have a very tough backing, which makes them good for final sharpening wrapped around something. Wet-or-dry sandpaper helps with the initial shaping. I have repurposed molding planes by changing the profile.

[Thomas Crawford]

Ah, that makes sense. Like an appropriate sized dowel wrapped in low grit sandpaper?

[Charles Guest]

Finally got a (near) half set of hollows and rounds. Got the irons de-rusted and some of them need a grinding due to a crummy job by the previous owner.

I was thinking of the DMT Diamond wave for honing: https://toolsforworkingwood.com/store/item/MS-WV.XX

What are my options for grinding? Particularly for the hollows. They are all skewed if that makes a difference.

450619

Be careful not to alter the shape of the irons (sweep of the curve) or they'll be useless or very close to it without changing the shape of the plane's bottom to match.

[Robert LaPlaca]

I found the Larry Williams videos available from Lie-Nielsen pretty helpful. The half set of Griffith’s I bought also was a skewed set. I used a 1x42 belt sander/grinder for the rounds and a mounted point in a Dremel for the hollows to regrind the irons to match the shape of the planes. I used Larry’s technique to use Dikem red and a scribe to mark the profile of the planes on the iron.

Make sure that you check the bodies of the planes along the escapement to make sure the plane isn’t bowed.

[Jim Koepke]

Hi Thomas, Are all those from the same maker or is it a mixed set?

Most likely more than half of the molding planes available today have had their blades buggered by a previous owner. Often the center of the blade gets all the abrasive action and the edges are untouched, especially on hollows.

Here is an old post of mine on rehabbing old molding planes > https://sawmillcreek.org/showthread.php?242156

Way down in the thread is this link > https://blog.lostartpress.com/2017/02/16/how-to-sharpen-moulding-plane-cutters/ < it is an article on sharpening molding plane blades.

The tapered diamond stones seem to have one problem, they are tapered. The area that can be used for a smaller blade is limited.

Using dowels our rods wrapped in abrasive sheets works okay, but it gets tedious fast.

When first starting on this when a blade got sharp enough to make a decent cut a profile would be cut and then abrasive sheets would be used on the profile to further refine the blade. Now a similar technique is used for stropping.

My current set up uses both oil and water slip stones.

Water stones are available here > https://www.leevalley.com/en-us/shop/tools/sharpening/stones/33013-traditional-water-slip-stones?item=60M9000 < They carry others, search their site for > slip stones <.

My oil slip stones are mostly from Dan's Whetstones > https://www.danswhetstone.com/product/slip-stones/ < They also have others including carver's slip stones. They also have round and oval Arkansas stone files that are useful on molding plane blades.

A couple of my oilstone slips are from Norton > https://www.nortonabrasives.com/en-us/product/crystolon-sc-round-edge-slip < one is a crystolon and another is an India stone.

A good book on using hollows & rounds for making moldings is Mouldings in Practice by Matthew Sheldon Bickford from Lost Art Press.

One thing to remember is the shape of the blade is more elliptical than round since it is 1/6th of a circle at an angle.

jtk

[Steve Voigt]

If you are asking about grinding the hollows, there are a couple options. You can buy a thin wheel from Tools For Working Wood and shape it to a desired radius. Those wheels are expensive. A cheaper option is to use chainsaw grinding wheels. I get them at Tractor Supply. They have a 7/8 arbor, so you will need an adaptor. If you have an 8" grinder, then the flange from a 4-1/2" angle grinder works great--you can get the flange cheap f you don't have an angle grinder. I'm sure there are other ways to solve that problem.
You can also grind with cylindrical or cone-shaped grinding tools that can be chucked in a drill press, but these are slow and awkward.

[Tom M King]

One method that might be useful is a variation of what I do when I'm matching old window sash. I use plumbers epoxy putty to make a mold. You can find it in the plumbing aisles of the box stores. You roll the two parts together in your hands to mix it, and then press it around what you want to get the negative of. I use the thinnest plastic sandwich wrap (from the girls at Subway) for a release agent between the part, and the epoxy.

You could use a couple of layers of wax paper laying in the sole of the plane you're matching, or whatever it takes to match the sandpaper thickness you'll use. Once it's cured, lay sandpaper on it, and make a wooden angle guide to match the bedding angle of the plane. In the picture, I had forgotten to take gloves with me, so used some of the plastic wrap to knead the epoxy, and get it in place. There was also a layer over the muntin for clean release.

Sometimes I have made molds off the molds, to get the other part.

[lowell holmes]

I would start with the least desirable chisel to develop my technigue.

[Thomas Crawford]

Hi Thomas, Are all those from the same maker or is it a mixed set?

Most likely more than half of the molding planes available today have had their blades buggered by a previous owner. Often the center of the blade gets all the abrasive action and the edges are untouched, especially on hollows.

Here is an old post of mine on rehabbing old molding planes > https://sawmillcreek.org/showthread.php?242156

Way down in the thread is this link > https://blog.lostartpress.com/2017/02/16/how-to-sharpen-moulding-plane-cutters/ < it is an article on sharpening molding plane blades.

The tapered diamond stones seem to have one problem, they are tapered. The area that can be used for a smaller blade is limited.

Using dowels our rods wrapped in abrasive sheets works okay, but it gets tedious fast.

When first starting on this when a blade got sharp enough to make a decent cut a profile would be cut and then abrasive sheets would be used on the profile to further refine the blade. Now a similar technique is used for stropping.

My current set up uses both oil and water slip stones.

Water stones are available here > https://www.leevalley.com/en-us/shop/tools/sharpening/stones/33013-traditional-water-slip-stones?item=60M9000 < They carry others, search their site for > slip stones <.

My oil slip stones are mostly from Dan's Whetstones > https://www.danswhetstone.com/product/slip-stones/ < They also have others including carver's slip stones. They also have round and oval Arkansas stone files that are useful on molding plane blades.

A couple of my oilstone slips are from Norton > https://www.nortonabrasives.com/en-us/product/crystolon-sc-round-edge-slip < one is a crystolon and another is an India stone.

A good book on using hollows & rounds for making moldings is Mouldings in Practice by Matthew Sheldon Bickford from Lost Art Press.

One thing to remember is the shape of the blade is more elliptical than round since it is 1/6th of a circle at an angle.

jtk

Thanks for all the links. They are mostly from 1 maker.

[Jim Matthews]

If your stash is like mine, the blades were made to fit the plane bodies and are difficult to replace.

I sharpen mine *only enough* to cut a given run.
I don't use high speed tools for fear of ruining blades I can't easily (or cheaply) replace.

*****

I have a slightly different approach, using the plane bodies as guides.

Apply painter's tape to the sole of the plane.

Insert the blade "proud" of the sole by 1/16".

Mark the bevel to be polished with a Sharpie or Dykem.

Use spray adhesive to attach 220 grit and 600 grit wet/dry sandpaper intended for metalwork to dowel rod. (Mine is from 3M and easily wraps in a tight circle.)

More than one diameter rod may be necessary.

I use small diamond "paddles" for the convex parts.

Hone the blade from the back of the plane toward the front, with the dowel (or paddle) resting on the plane sole. This will raise a fine burr, only at the tip of the iron.

When a bright line appears on the marked section of the bevel, remove the blade and lap off the burr.

The tape might show some wear during use, but it's intended to be wasted as a protective layer.

Clear the sole with a mild solvent and reapply wax prior to use.

*****

It is important to remember that wood species, and grain selection are vital to creating crisp moldings.

The irons used in most antique molding planes are very soft, and will dull or deform in harder woods.