General Racing Discussion Open discussion about racing and racing related topics

Prather Pitch Gauge

Reply
Old 11-17-2013, 11:20 AM
  #1
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Prather Pitch Gauge

Please see my listing.

http://www.ebay.com/itm/141116239987...84.m1555.l2649

Thanks, D
daven is offline  
Reply With Quote
Old 11-18-2013, 05:46 PM
  #2
skull1971
 
skull1971's Avatar
 
Join Date: Apr 2006
Location: Willis, TX
Posts: 1,569
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Really Dave? thought we were better than this
skull1971 is offline  
Reply With Quote
Old 11-18-2013, 06:42 PM
  #3
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Better than what? Helping someone else out that can use this now that I am done with it?
daven is offline  
Reply With Quote
Old 11-19-2013, 03:51 AM
  #4
skull1971
 
skull1971's Avatar
 
Join Date: Apr 2006
Location: Willis, TX
Posts: 1,569
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I was just hoping to get it in the "Brother-in-law" deal instead of hand to hand combat on ebay.
skull1971 is offline  
Reply With Quote
Old 11-19-2013, 04:27 AM
  #5
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Ahhh... I get you now... Well, that I understand, but I'm trying to maxamize my $'s..... Could really use some extra cash for Xmas and maybe a trip... Just selling off a few odds and ends that appear to be highly coveted at the moment..
daven is offline  
Reply With Quote
Old 11-19-2013, 04:28 AM
  #6
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

and not to be mean, but I really hope there is LOTS of "hand to hand" fighting over there, lol...
daven is offline  
Reply With Quote
Old 11-19-2013, 06:36 AM
  #7
twitte1
 
Join Date: Oct 2005
Location: Knightdale, NC
Posts: 170
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Dave,

How much for a PDF copy of the instructions??

Trey
twitte1 is offline  
Reply With Quote
Old 11-19-2013, 07:18 AM
  #8
ALbert.S
 
Join Date: Jul 2002
Location: Roseville, MN
Posts: 263
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Dave people are willing to pay real money for old stuff ???? I have one here somewhere in my "Hobby " stuff I'll have to look for it
I didn't know you could get $$$$ for old stuff haven't used it since we quit Quarter midget WOW
ALbert.S is offline  
Reply With Quote
Old 11-19-2013, 07:21 AM
  #9
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Some are I guess Al... One of these sold on EBAY for over $100 recently... I guess some of the Control Line guys still use them, and some still use them for Q40 props... I just take em out of the bag and go...

Trey, I'll do my best to scan these in the next day or so. PM me your email.

D
daven is offline  
Reply With Quote
Old 11-19-2013, 08:10 AM
  #10
skull1971
 
skull1971's Avatar
 
Join Date: Apr 2006
Location: Willis, TX
Posts: 1,569
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Add me to that too Dave, a copy of the instructions. I think you already have my email address.
skull1971 is offline  
Reply With Quote
Old 11-19-2013, 09:52 AM
  #11
ALbert.S
 
Join Date: Jul 2002
Location: Roseville, MN
Posts: 263
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I founed it !!! A little dusty but still usable
ALbert.S is offline  
Reply With Quote
Old 11-20-2013, 01:11 PM
  #12
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Mines up to $177.00 Al, with several days to go... Better get yours listed
daven is offline  
Reply With Quote
Old 11-20-2013, 01:23 PM
  #13
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Actually, make that $280 now, wow...
daven is offline  
Reply With Quote
Old 11-21-2013, 03:04 PM
  #14
HighPlains
 
Join Date: Mar 2003
Location: Over da rainbow, KS
Posts: 5,068
Default

A $1.29 and a bit of trig will get just as good an angle.
HighPlains is offline  
Reply With Quote
Old 11-21-2013, 03:46 PM
  #15
fizzwater2
 
Join Date: Aug 2004
Location: Paola, KS
Posts: 2,719
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

yeah, but if you're SELLING the pitch gauge, 280 is pretty darned good!

I still have one that I think is NIB, might hang on to it a while longer.. it seems they must be made of unobtanium.
fizzwater2 is offline  
Reply With Quote
Old 11-21-2013, 04:49 PM
  #16
HighPlains
 
Join Date: Mar 2003
Location: Over da rainbow, KS
Posts: 5,068
Default

I always thought the Prather must have found the design from overseas. The bed is metric (centimeter spacing) while the gage is in 3 grains of barley.
HighPlains is offline  
Reply With Quote
Old 11-21-2013, 07:00 PM
  #17
speedracerntrixie
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 5,338
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

So what would a guy use to measure pitch while trying to mod up a prop to a 13x15 or maybe a 12x16?
speedracerntrixie is offline  
Reply With Quote
Old 11-23-2013, 08:23 AM
  #18
HighPlains
 
Join Date: Mar 2003
Location: Over da rainbow, KS
Posts: 5,068
Default

Shawn,

You can make a very good pitch gauge for not too much cash with a protractor. The Prather gauge was not all that accurate, as you could skew the measurements by a number of ways.

To build a prop gauge, I would start with a good digital protractor like this General Tool model for $30.

http://www.generaltools.com/1702--DI...OR_p_1245.html#

Next you need a measurement board. Use a flat sheet of aluminum, about 1/4" thick or maybe slightly thicker plastic that is a bit longer than the largest prop you want to measure and maybe 4 to 6 inches wide (It will need to be pretty wide to measure flatter angles at the tips of props).

Drill and tap on one end for the different stud sizes of the props you want to use. Might be three or more sizes, but if you run out of room on one end you can also use the other end too.

Finally mill or cut slots through the board for the protractor arm to go through the base at the spacing you want to measure. As I said before, the Prather unit's station spacing was in cm, so if you want a direct comparison to a Prather, go with that.

To use, mount the prop using a short thread or bolt to the base. Insert protractor from the other side and take a measurement. Do the math to find out the inches of pitch at that station.

If you find out that one blade is higher or lower than the other, don't change the blade, change the hub. If the front and the back of the prop hub is not exactly parallel, then it's a good chance that blades won't track in pitch. You can scrap the rear of the hub with a single edge razor blade to get them right with each other. Then go ahead to change each blade as desired.
HighPlains is offline  
Reply With Quote
Old 11-23-2013, 10:18 AM
  #19
speedracerntrixie
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 5,338
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Thanks Bob, pretty much what I was thinking. The thing that I didn't think about was adjusting the hub. The goal is to see how small a dia I will have to go to get a YS 115 to spin a 15 or 16 inch pitch prop at 10k. Then decide if the airplane is clean enough to use the prop. I need to end up with an airplane that is close to 190 mph. Wings are getting sheeted this weekend.
speedracerntrixie is offline  
Reply With Quote
Old 11-24-2013, 04:09 PM
  #20
daven
Thread Starter
 
Join Date: Dec 2001
Location: Waseca, MN
Posts: 8,452
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

$330, wow.. shipping tomorrow, thanks!
daven is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 09:51 AM.