LV Plow Plane question

[Doug Shepard]

I might be interested in picking one of these up. Primarily as a way to put 1/16" inlay grooves in stuff rather than doing them with a laminate trimmer and edge guide. The 1/16" bits can be pretty fragile plus there's the normal reasons for wanting to do things with hand tools at times. But their smallest cutters are 1/8". For somebody with ZERO skill at making their own cutting irons and only a standard grinder available, is there a way to grind a 1/8" down to 1/16"? And how would one do it so that it's was exactly 1/16" for some portion of it's length (say maybe to 1/4" or so)? And is there a reason why a cutter that narrow might not work well with this tool?

[Larry Williams]

Just a guess here but I would expect the skate to be more than 1/16" thick. An iron narrower than the skate isn't going to cut deeper than the shaving thickness the plane is set for.

[Wiley Horne]

Doug,

What Larry said. The skate is in the way.

The simplest and best (my opinion after using several options) tool is the simple scratch stock. There are a zillion versions, but here is a version commercially made by Lee Valley:

http://www.leevalley.com/wood/page.a...79&cat=1,41182

Now you don't need to buy that tool--just trying to give you the idea. You can make something similar yourself, and it doesn't need to be fancy, just sturdy. The question is what to grind into a cutter. Any piece of hardened steel will do. Three choices would be (a) drill bit, (b) sabre saw blade, (c) masonry nail (it's hardened). Any of these are easy to slot for in the movable arm of the scratch stock. Probably the sabre saw blade is the easiest to square up.

The main thing about the cutter is that it needs to be square, and it needs to be sharp--meaning honed--on all 4 sides, plus the bottom. That way, it is presenting sharp edges to the work, whether coming or going. When you use a scratch stock, you want to be working with the grain, not against it, so it's nice for it to go either way in the work. Grind it to ever so slight of a taper--like 3/64"+ where it enters the work, and 1/16" at the top. This will ensure a clean precise cut at the surface (no 'run out' so to speak). The sabre saw blade is easy to prepare, because you already have 2 parallel sides; with a drill bit or masonry nail, you have to take something round and make something square out of it.

To use the tool, you 'roll' the cutter into the work, starting by just scratching and cutting the surface fibers, and then gradually lowering the blade into the work by rotating the tool toward you (this is intuitively obvious when you're actually doing it). If you go with the grain, and if the cutter is sharp, you'll get a perfectly clean cut, even in something splintery like cherry.

Stringing cuts are stopped cuts. That means you have an issue at either end. I use a very narrow chisel or gouge (like 1mm) to define the end limits and even dig out a short little mortise that I can easily see; then use the scratch stock between these end cuts. It helps to control the scratch stock if you have clearly defined end points--don't guess where the end point is (DAMHIKT).

Wiley

[Gary Herrmann]

Doug, will the grooves be cross-grain at all - if so, the plow plane won't help you much without prep. It works very well with the grain, but you'll need something with nickers or you'll have to prep if you go crossgrain.

I wonder who will come out with a fillister or dado plane first - LV or LN?

[Alice Frampton]

Just a guess here but I would expect the skate to be more than 1/16" thick.

Yep, it's 3/32"

Strikes me as all the wrong tool for the task anyway. Wiley's excellent advice on the scratch stock seems to me to be the way to go - having seen pictures of his incredible inlay work.

Cheers, Alf

[Doug Shepard]

Muchos gracias mi amigos.
You saved me at least $209. Hadn't thought about the cross-grain question either. So far IIRC it's always been with the grain but I might need to go cross-grain once in a while too. I'll put the scratch stock idea on my future plans list. Got too many things already on my To-Do list so I guess I'll just stick with the power tool for right now.