nigellogan Posted March 18, 2007 Share Posted March 18, 2007 I have embarked on an ambitious project to construct a 30 key anglo and I am planning to construct the action levers de novo out of brass (as described by Henrik Muller) but I am seeking guidance on the profile. Can anyone help? Thanks, Nigel Logan nigel@old-lyme.com Link to comment Share on other sites More sharing options...
d.elliott Posted March 18, 2007 Share Posted March 18, 2007 what do you mean by 'profile' Dave Link to comment Share on other sites More sharing options...
Richard Morse Posted March 18, 2007 Share Posted March 18, 2007 The "ideal" (IMHO) parameters for the lever profile is that" The fulcrum post pivot hole be located at an elevation 1/2 way between the button lever hole when the pad is closed and when it is fully open (makes for the least friction at the button end due to lever arm swing/angle). The pivot point be located correctly for optimum button-motion to pad motion distances (which is NOT in the center of the lever). That the angle of the pad end of the lever is parallel to the pad (for good donuts/dots, etc. securance). The lever should be flat at the pivot to minimize any sideways or rotational motion. The lever should be stiff enough (ideally through section profile: tall/thin), and distributed well to insure positive motion (no flexure) and yet be light (better response and easier to heft the box). The lever, post and rivet should be of compatible materials (to prevent undue wear and galling problems). While designs of having the lever at the post encapsulated in a dowel of sorts looks pretty, there is concern of friction now on both sides of the lever - and that the size of the post may interfere with placement and operation of adjacent levers and springs. A good profile is the result of taking all the aboves into consideration - and is usually different for each lever as the padhole/button distances vary. Good luck with your project! -- Rich -- Link to comment Share on other sites More sharing options...
nigellogan Posted March 18, 2007 Author Share Posted March 18, 2007 (edited) I have embarked on an ambitious project to construct a 30 key anglo and I am planning to construct the action levers de novo out of brass (as described by Henrik Muller) but I am seeking guidance on the profile. Can anyone help? Thanks, Nigel Logan nigel@old-lyme.com Sorry, I was meaning design features (ratio of length to depth, ratio of length either side of fulcrum etc) Edited March 18, 2007 by nigellogan Link to comment Share on other sites More sharing options...
nigellogan Posted March 18, 2007 Author Share Posted March 18, 2007 The "ideal" (IMHO) parameters for the lever profile is that" The fulcrum post pivot hole be located at an elevation 1/2 way between the button lever hole when the pad is closed and when it is fully open (makes for the least friction at the button end due to lever arm swing/angle). The pivot point be located correctly for optimum button-motion to pad motion distances (which is NOT in the center of the lever). That the angle of the pad end of the lever is parallel to the pad (for good donuts/dots, etc. securance). The lever should be flat at the pivot to minimize any sideways or rotational motion. The lever should be stiff enough (ideally through section profile: tall/thin), and distributed well to insure positive motion (no flexure) and yet be light (better response and easier to heft the box). The lever, post and rivet should be of compatible materials (to prevent undue wear and galling problems). While designs of having the lever at the post encapsulated in a dowel of sorts looks pretty, there is concern of friction now on both sides of the lever - and that the size of the post may interfere with placement and operation of adjacent levers and springs. A good profile is the result of taking all the aboves into consideration - and is usually different for each lever as the padhole/button distances vary. Good luck with your project! -- Rich -- Great - this was exactly the type of guidance I was seeking - many thanks, N Link to comment Share on other sites More sharing options...
chris Posted March 19, 2007 Share Posted March 19, 2007 hi attached (hopefully) is a pic of the action in my J Scates 'english' which shows levers that look 'cast' rather than pressed wire. this method cut from plate may be feasable and maybe easier than wire have fun chris Link to comment Share on other sites More sharing options...
d.elliott Posted March 20, 2007 Share Posted March 20, 2007 do you perhaps think that we can substitute wrought, forged, or stamped for cast? Dave E Link to comment Share on other sites More sharing options...
chris Posted March 21, 2007 Share Posted March 21, 2007 Hi Dave you can substitute whatever you wish, or feel to be more accurate. I am not an engineer nor a metal worker so I don't tend to think along the lines of wrought,forged or stamped. I posted really to demonstrate that there are levers other than wire that Nigel may wish to consider. chris Link to comment Share on other sites More sharing options...
Dave Prebble Posted March 21, 2007 Share Posted March 21, 2007 hiattached (hopefully) is a pic of the action in my J Scates 'english' which shows levers that look 'cast' rather than pressed wire. this method cut from plate may be feasable and maybe easier than wire have fun chris Hi Chris, thanks for posting the photo - great definition btw I rather like this type of action. it makes for a nice stable pivot point and seems far less prone to clattering than Lachenal type hook actions. I have only ever seen them on English concertinas by Scates and Nickolds They are a joy to work on. Simply unhook the spring, a gentle push down at the pivot and the arm, complete with pad, just unhooks and lifts away. Regards Dave P Link to comment Share on other sites More sharing options...
chris Posted March 21, 2007 Share Posted March 21, 2007 Hi Dave I wasn't aware that Nickolds had used that action. I went and looked at a very early J Scates, Number 19 subsequently bought by someone else and noted that the action for that one was the same as used in a friends Nickolds see attached (hopefully) photo (courtesy of original ebay seller) I did wonder, who actually made mine. Bought for £48 about 1977/80 and can be seen as my avatar chris Link to comment Share on other sites More sharing options...
Dave Prebble Posted March 21, 2007 Share Posted March 21, 2007 Hi DaveI wasn't aware that Nickolds had used that action. I went and looked at a very early J Scates, Number 19 subsequently bought by someone else and noted that the action for that one was the same as used in a friends Nickolds see attached (hopefully) photo (courtesy of original ebay seller) I did wonder, who actually made mine. Bought for £48 about 1977/80 and can be seen as my avatar chris Hi Chris, I guess these guys were either varying their designs or, quite likely, using the same outworkers for some of their parts. The Nickolds I had, funnily enough, came from a Sussex antique shop for .... £48 some twenty five or so years ago. It was a nice instrument with finely fretworked and inlaid ebony ends and when restored, both looked and played like a dream. I shall always remember that box... principally because It went in a straight swap for a 38 button Bb/F Jeffries (albeit one in pretty bad shape) Regards Dave Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now