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  #21  
Old 02-16-2018, 10:05 AM
EXflyer EXflyer is offline
 
Join Date: Jan 2016
Location: Chiloquin OR
Posts: 94
Default Nice work

Well this is a fun thread to watch nice work as usual with a little fun while doing it. Thought this would happen, who can come up with something new or different wood..........or?
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  #22  
Old 02-16-2018, 10:19 AM
Sam Buchanan's Avatar
Sam Buchanan Sam Buchanan is offline
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Location: North Alabama
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Quote:
Originally Posted by M McGraw View Post
I “borrowed” this idea. The second picture is a slight modification I needed to eliminate binding while returning the tail to the floor.
There is more going on with these simple lifts in regard to engineering than might be at first apparent. My engineering background is limited to the shadetree variety but some simple analysis might reveal why some wood lifts slide effortlessly and others may bind.

If binding occurs on the aft slide block then more than likely the cable attachment needs to be closer to the tailwheel centerline. This will decrease the length of the arm supporting weight and the resulting load on the aft block.

Compare the cable attachment geometry on these two lifts:

Mine (cable aligned more or less even with rear of tailwheel, and the cable parallel with the ramp):



Marvin's (lift strap aligned with a point several inches aft of the tailwheel):



The dolly slides up and down with no binding on my lift and I suspect it is because the cable is closer to the tailwheel. If Marvin moves the attachment of the strap closer to the tailwheel (shorten the load arm and transfer weight from the rear slide block) I bet it will operate more smoothly.

I realize this stuff is pretty insignificant in the grand scheme of things but it is still interesting to play with. As a side note--I'm always amazed at how huge structures in antiquity were constructed with highly engineered simple machines.....them folks were smart!
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Last edited by Sam Buchanan : 02-16-2018 at 10:36 AM.
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  #23  
Old 02-17-2018, 09:20 AM
EXflyer EXflyer is offline
 
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Location: Chiloquin OR
Posts: 94
Default Slide

Might just take a piece of nylon sheet on the bottom inside of it as that's where most of the force is against the vertical piece.
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  #24  
Old 02-17-2018, 10:01 AM
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Snowflake Snowflake is offline
 
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Location: Sidney, BC, Canada
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Quote:
Originally Posted by EXflyer View Post
Might just take a piece of nylon sheet on the bottom inside of it as that's where most of the force is against the vertical piece.
Or a piece of the UHMW tape left over from protecting your aft wing skin from your flaps...
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1996 RV-6 "Tweety" C-FRBP (formerly N196RV)
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  #25  
Old 02-17-2018, 12:11 PM
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Sam Buchanan Sam Buchanan is offline
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The lift will work beautifully wood-on-wood if set up properly, no additional material needed.
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  #26  
Old 02-17-2018, 04:26 PM
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M McGraw M McGraw is offline
 
Join Date: Dec 2012
Location: Greenback, TN
Posts: 588
Default Lift

I agree with Sam that the lift works fine wood on wood. In my case I have a tail light and an 8” tire that did not allow moving the attach point forward like Sam’s because the strap would rub. If you look closely at the picture you will notice my tail wheel axle is actually a few inches forward of where I intended. My choices were to increase the angle of the lift to clear the tail light or increase the length of the backside of the moveable trolly.
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Last edited by M McGraw : 02-17-2018 at 04:29 PM.
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  #27  
Old 02-18-2018, 09:59 AM
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Greg Arehart Greg Arehart is offline
 
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Location: Delta, CO/Atlin, BC
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Default

When I built one of these years ago, instead of the block in the back that slides, I used a bolt with a bunch of plywood wheels (pieces from another project cut using a hole saw) to allow for easier movement.

Also, instead of a bolt keeping the tailwheel in, I just left the metal plate with a gap at the back, so the tailwheel drops into that space when the tail is lifted.
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  #28  
Old 02-18-2018, 12:24 PM
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Sam Buchanan Sam Buchanan is offline
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Location: North Alabama
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Quote:
Originally Posted by M McGraw View Post
I agree with Sam that the lift works fine wood on wood. In my case I have a tail light and an 8” tire that did not allow moving the attach point forward like Sam’s because the strap would rub. If you look closely at the picture you will notice my tail wheel axle is actually a few inches forward of where I intended. My choices were to increase the angle of the lift to clear the tail light or increase the length of the backside of the moveable trolly.
Quote:
Originally Posted by Greg Arehart View Post
When I built one of these years ago, instead of the block in the back that slides, I used a bolt with a bunch of plywood wheels (pieces from another project cut using a hole saw) to allow for easier movement.

Also, instead of a bolt keeping the tailwheel in, I just left the metal plate with a gap at the back, so the tailwheel drops into that space when the tail is lifted.
My first "design" was going to have rollers cut out of delrin rod, similar to the original TailMate. But I decided to try the 2x4 wood sliders first and they worked so well the roller idea was shelved.

That is the beauty of this little custom project, it can be individualized to suit the particular application. Marvin modded his to make it work for him and rollers may be the best solution for a heavier aircraft. I'm considering 1/8" 6061 sides for the dolly with the floor riveted via angles to the sides.....just have to decide when good is good enough.
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Last edited by Sam Buchanan : 02-18-2018 at 12:28 PM.
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  #29  
Old 02-18-2018, 04:02 PM
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RV8Squaz RV8Squaz is offline
 
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Location: Senoia, Georgia
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Here’s my version of the wooden Tail-Mate. I’ve got inverted oil on my airplane and the quick drain is on forward part of the sump. Consequently, I like to raise the tail high enough during oil changes to ensure I drain all the oil. I super-sized my Tail-Mate!















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Last edited by RV8Squaz : 02-18-2018 at 04:12 PM. Reason: Added photos.
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  #30  
Old 02-18-2018, 07:11 PM
phobos_49 phobos_49 is offline
 
Join Date: Aug 2006
Location: Hicks (T67)
Posts: 62
Default I'm not Archimedes

You are fighting the 7:1 ratio. This is ancient engineering.

Your slide must be more vertical or your tail wheel block must be taller. This will fix your problem.

Jarhead
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