Tips for achieving this forearm profile

[JonBishop]

Hi all,

I would like to know what some of you accomplished builders do to profile your forearm wood. This is my last step to finishing this stock for now. I have some ideas but I am a bit afraid of going for it. I have some layout lines on it. You can see them in the picture.

Thanks, Jon

 

[rchas]

My favorite tool to rough in a stock forearm is a spokeshave. When I have it close, I use a homemade scratch-stock with a cutter made out of a piece of an old saw blade. The cutter is filed to the shape of the profile of the forearm. The top of the scratch-stock runs along the top of the barrel channel and the cutter forms the profile after several passes. The picture is sideways to the way you use the tool. The advantage is the profile is the same the length of the stock and both sides, and you can cut a molding at the same time.

 

[JonBishop]

That’s great! That was an idea I had. But the simple jig you have is a lot better than the one I was thinking about. I was thinking complicated adjustable type thing. Did you make the cutter with just files? If so, did you soften the saw blade then heat treat? I was thinking of making something similar from some 1084 steel. It would have to be heat treated of course.

Thanks, Jon

 

[rchas]

Wood saw blades are soft enough to cut with a file, but will hold an edge. I ground the profile close, then finished with files. When the scraper/cutter needs sharpening I lay it flat on a stone to touch it up. There is a saw slot cut down the center of the arm the cutter slides into, it is tightened by the two screws. It works best by angleing slightly in the direction you are scraping-- you can pull or push it as needed. The picture is of a forearm done with the cutter in the scratch-stock.

 

[Col. Batguano]

Use a long soled implement, like a Japanese rasp for your primary shaping. That will keep things even along a longer plane. If you use something shorter, like scrapers, the risk is that you will get a wavy surface as the cutting surface goes over hard and soft spots.

 

[tenngun]

I like to pick up a dowel as big as can fit in the channel and tape it in. Then I can work on it with out giving my self a month of constipation.

 

[pooch156]

Wood saw blades are soft enough to cut with a file, but will hold an edge. I ground the profile close, then finished with files. When the scraper/cutter needs sharpening I lay it flat on a stone to touch it up. There is a saw slot cut down the center of the arm the cutter slides into, it is tightened by the two screws. It works best by angleing slightly in the direction you are scraping-- you can pull or push it as needed. The picture is of a forearm done with the cutter in the scratch-stock.
View attachment 75553

That is a beautiful profile!

 

[pooch156]

Use a long soled implement, like a Japanese rasp for your primary shaping. That will keep things even along a longer plane. If you use something shorter, like scrapers, the risk is that you will get a wavy surface as the cutting surface goes over hard and soft spots.

My barrel, across the one set of flats was wider than the others. My barrel channel was cut to 15/16" wide while my barrel was slightly wider which meant having to take out more material than was needed on my previous three builds. So I made a scraper that would ride on the top of the barrel channel while scraping the side flats of the channel. Shortly after I started scraping I noticed a wavy appearance to the the area being scraped. My scraper, although sharp, was skipping over the harder "rays" in the stock. I caught it in time. Lessen learned. I don't think that I would have had much of an issue had the stock been cherry, walnut or just plain maple. But mine is CM3.

 

[rchas]

Use a long soled implement, like a Japanese rasp for your primary shaping. That will keep things even along a longer plane. If you use something shorter, like scrapers, the risk is that you will get a wavy surface as the cutting surface goes over hard and soft spots.

True, that may happen. When I built my first rifles, I did my best to get perfect finishes on the wood and perfect polishes on the metal. That is a worthy goal, and I admire the time, effort and patience it takes to get to achieve that work. I don't have that level of skill--maybe when I retire I can spend more time on it. In any case my interests began to go in a different direction. I started reading and researching on period tools, methods and finishes to achieve a "workmanlike" result. The scratch stock is a period tool, and traces of it's use can be seen on period rifles, namely a "wavy surface" depending on the grain of the wood. But it does work, and very well. It all depends on what results you want to achieve.

 

[JonBishop]

I like to pick up a dowel as big as can fit in the channel and tape it in. Then I can work on it with out giving my self a month of constipation.

Do you mean that you find a dowel and tape sandpaper to it? I thought about this as well. I think that there is a reference to it in “Recreating the American Long Rifle”. But the jig seems overly complicated. Something like @rchas posted is much simpler. I think that could be modified to use sandpaper on a dowel.

Jon

 

[Vaino]

All my LRs have an upper forestock molding and a line is cut in w/ the tool riding in the RR groove......this tool can concave the molding, but I don't use it for that. The adjustable set screw is the cutter. The forestock shape has to be nearly done to use this tool. I don't use contoured scrapers to shape the forestock...it's all done by "eyeball". Nothing wrong w/ using scrapers...I just don't use them. Two forestock shapes are used on my LRs....oval and "V" shapes.......Fred