Reed gapping establishing the zero-point question
Hello,
I would really try and finetune my instruments.
So I am curently working my way through Harp Tech Study 4 - Reed Gapping.
I seem to be missing the point how to increase the gap at the base of the reed in case it is too tight.
I got the point how it can be decreased with those lessons:
Reed Gapping - Level 2: Setting the Zero-Point All at OnceReed Gapping - Level 2: Setting the Zero-Point with One Reed
but I am missing the point how it can be increased.
Can you please jhelp me with more info about how to increase the gap at the base of the reed in case it is too tight?
Thanks in advance!
WOW! I have certainly not been expecting such a detiled answer.
Wonderfully and professionaly explained!
Million thanks, Kinya!
We endeavor to provide you with the best knowledge we know how. Good luck Angel, stay in touch.
Your Harpsmith, Kinya
I've been trying to set the zero point and I have been using the end of my .002 gauge with the hole and pulling the shim back towards the rivet. I have found that sometimes the shim will actually peel a brass burr off the embossed/sized reed plate that then needs to be removed from the slot. I've never had success pushing the feeler gauge tip in and under the reeds, it's just too flimsy. Any comments or pointers Kinya?
Hi Grasshopper, please refer to the alternate techniques I used in the last three photos (and linked Harp Tech Series).
https://www.bluesharmonica.com/zero_point_tip_of_the_year
Your Harpsmith, Kinya
Hello Angel, thank you for your question regarding adjusting the zero point.
For readers not familiar with Zero Point, it is a term coined by Dick Sjoberg--the inventor of the Harp Tuning Table--used to define the gap at the rivet end of the reed.Specifically, the shaft of the reed that transitions into the rivet pad--the last part of the reed that butts up to the far side of the reed plate slot.
Top View
Angle View
With the reeds facing away from you, stand the reed plate on it’s end on top of a white background (preferably a light box)
With the slivers of light shining through the reed slot, you will be able to see the knife edge outline meeting the rivet end of the reed plate. This is your Zero Point gap
This close up shows that the free end reed gap is approximately .006” and the Zero Point gap is .002”
Angel requested, “Can you please help me with more info about how to increase the gap at the base of the reed in case it is too tight” (less than .002”)
TECHNIQUE: Have ready your .002” and .003” feeler gauge (shims)
Carefully (not shown, also place a finger on top of the reed to prevent any bucking upward) slide the .002” feeler gauge (shim) under the reed and push back all the way until it stops. Repeat about three times. Next, pull out the shim, then repeat the above light box examination to visually check the new gap.
Here is another way to approach the Zero Point. For better control, try “Pulling” the feeler gauge, instead of pushing the feeler gauge (shim). Tip: trim the radius off the feeler gauge. This will come in handy when you Profile your reed.
If the .002” feeler gauge does not raise the zero point, try this:
Push a .003” feeler gauge all the way back.
Your Harpsmith, Kinya