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    Downward sloping table - yay or nay?

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    kiltedcelt
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    Downward sloping table - yay or nay?

    Post by kiltedcelt on Thu Oct 14, 2010 2:12 pm

    I'm getting close to the point where I'll be shaping the tiller for two bows. Neither bow has a quarrel groove but both of them have a small rest at the front of the tiller with a quarrel groove in it. I've seen one guy do a build along for a bow and he actually had the table sloped downwards slightly and that little quarrel rest had its topmost part on a level with the rest of the table and the roller nut. Here is a link to a photo showing his bow before the quarrel rest was installed:

    http://www.stormthewalls.kicks-ass.net/Crossbows/Full/Construction/NoseSlope.jpg

    Here are the two bows I'm more or less trying to duplicate:





    In both cases I can't tell from the photos whether these bows have a sloped table forward of the area where the string rests, which is where I'm assuming the slope would start. Question is, do these bows slope down or would the quarrel rest stick up above the flat surface of the table slightly giving a ramped rest of sorts as Geezer has mentioned some bows having had? How would you make these tillers? Flat from the nut forward, or some downward slope?
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    DARIVS ARCHITECTVS
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    Re: Downward sloping table - yay or nay?

    Post by DARIVS ARCHITECTVS on Sat Oct 16, 2010 6:47 pm

    The table begins to slope just in front of the brace position of the string, as you guessed. The reason it slopes is to allow a bit more space in height for the arrow rest which is dovetailed in the stock in a transverse direction. Think of it this way. The arrow rest rises up to meet the quarrel shaft but does not lift the quarrel out of the plane of the string's motion. Nor is it too low such that it offers no support to the quarrel shaft. The amount of slope is rather small, less that half the height dimension of the arrow rest. The less slope, the shorter the arrow rest must be.

    The string must move directly behind the center axis of the quarrel throughout its throw. The area of the table which is sloped never has to contact the quarrel shaft, so there is not friction to slow the quarrel down. The slope offers this small advantage over a full length table groove.

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