Plastic Kuhn Fin Jigs

RandyT0001 · Oct 12, 2014

I was looking at some 11/16" PVC corner molding online and thought I could use it to make some Kuhn fin jigs of several fin thicknesses. So I went to the local big box home improvement center and bought an 8 foot long piece for about $5. I cut several pieces about 8 inches long then I carefully used my razor saw to cut the fin slots into the jigs. I sanded the slots to their final sizes. I had to practice a couple of times before I got it right, slot centered and at a 45 degree angle to the sides. Here's a pic:

K'Tesh · Oct 12, 2014

RandyT0001 said:
I was looking at some 11/16" PVC corner molding online and thought I could use it to make some Kuhn fin jigs of several fin thicknesses. So I went to the local big box home improvement center and bought an 8 foot long piece for about $5. I cut several pieces about 8 inches long then I carefully used my razor saw to cut the fin slots into the jigs. I sanded the slots to their final sizes. I had to practice a couple of times before I got it right, slot centered and at a 45 degree angle to the sides. Here's a pic:

The Estes fin guide that I have is similar to those, and all of my L1's fins are "off" by the same amount. I'd say that spending the money to buy some foam board (a dollar at Dollartree), a glue stick, and a printed guide from Payloadbay.com is probably a better investment.

Micromeister · Oct 15, 2014

RandyT0001 said:
I was looking at some 11/16" PVC corner molding online and thought I could use it to make some Kuhn fin jigs of several fin thicknesses. So I went to the local big box home improvement center and bought an 8 foot long piece for about $5. I cut several pieces about 8 inches long then I carefully used my razor saw to cut the fin slots into the jigs. I sanded the slots to their final sizes. I had to practice a couple of times before I got it right, slot centered and at a 45 degree angle to the sides. Here's a pic:

Plastics are subject to warping with temperature and pressure. While a step up from Wooden Corner moldings, I don't use plastic angles for anything. Instead you might want to try Aluminum angles for such things. 1/2" x 1/2" x .063", 3/4" x 3/4" x 1/8" and 1" x 1" x 1/8" are common sizes available just about anywhere.

accooper · Oct 16, 2014

K'Tesh said:
The Estes fin guide that I have is similar to those, and all of my L1's fins are "off" by the same amount. I'd say that spending the money to buy some foam board (a dollar at Dollartree), a glue stick, and a printed guide from Payloadbay.com is probably a better investment.

Where on payloadbay is this tool. I can't find it.

Andrew

K'Tesh · Oct 16, 2014

accooper said:
Where on payloadbay is this tool. I can't find it.

Andrew

https://blog.Payloadbay.com -> Tools -> Fin Guide Tool (or just click this link)

RoyAtl · Oct 16, 2014

K'Tesh said:
https://blog.Payloadbay.com -> Tools -> Fin Guide Tool (or just click this link)

previous info deleted. I mis-read the error message. <emily litella>Never Mind!</emily litella>

K'Tesh · Oct 16, 2014

RoyAtl said:
Except you can't do a guide for a tube less than 1.0" dia (i.e. BT-50, BT-20, or BT-5, despite them being listed in the combo box).

You *could* try making one that uses a 1" diameter, and fin thicknesses scaled up to the 1" diameter, then photocopy it while reducing it at the same time.

RoyAtl · Oct 16, 2014

K'Tesh said:
You *could* try making one that uses a 1" diameter, and fin thicknesses scaled up to the 1" diameter, then photocopy it while reducing it at the same time.

or you could ignore what I said! Darn it, you quoted it before I deleted it!

K'Tesh · Oct 16, 2014

RoyAtl said:
or you could ignore what I said! Darn it, you quoted it before I deleted it!

Ya gotta be pretty fast around here... :wink:

Plastic Kuhn Fin Jigs

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Plastic Kuhn Fin Jigs

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