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  #1  
Old 11-20-2018, 03:58 PM
RB86 RB86 is offline
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Default Long Tuck Shrinking

Is there any advantage/reason for making some long tucking forks to get shrink happening further in from the edge of a panel? Or would that cause issues? I'm trying to get a panel to start wrapping downward about 7 inches from the edge on the inside of a fender. Or is it better to block that line while holding the panel on an angle to get the bend started there? Hope that makes sense.

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Last edited by Steve Hamilton; 11-21-2018 at 01:23 PM.
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Old 11-21-2018, 12:33 PM
RB86 RB86 is offline
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I guess not haha
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Old 11-21-2018, 02:09 PM
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Kerry Pinkerton Kerry Pinkerton is offline
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You can Rob but it's not really a novice technique. A couple things to keep in mind.

1- Tuck shrinking really only works well when the panel is fairly flat. Once it gets shrunk on the edges, it's much more difficult to get the tucking forks in place.

2- Therefore, start tuck shrinking as deep as you will think you will ever need. Stretching is easy...shrinking is hard so if you over shrink, you can easily stretch it back out.

3- Shrinking happens in a pie shape. If you want a wedge shaped shrink say 3" deep and you want to shrink 1/4 of an inch 3" into the panel. Think about how much the panel has to shrink on the edge...probably 1" and 1/2" about at about 1.5" in.

4- Finally, the way to shrink deeper into the panel is to make a big tuck and just close the EDGE. Leave the bubble above it. You can then, with practice, drive the shrink inboard.

It might help you to watch this video of my son Kris demonstrating our approach to tuck shrinking... https://www.youtube.com/watch?v=mkaCJ5gC3jI

While you are on youtube you can search for tuck shrinking and there are others. There are lots of ways to do it and folks evolve a method that works for them. If someone is teaching you who says that their way is the only way...find another teacher.

Finally, you mentioned you were hammering out your tucks on the floor. I suggest you at the minimum use a piece of 2x12 until you get a stump. Wood seems to hold the tuck up and keep it from sliding open better. You can do it on concrete but you'll get grit in your panel and spend more energy than necessary.

When you find a stump (call up some tree surgeons...they can't split big stumps and have to pay to get rid of them. If you ask nice, they'll cut it to length for you. You want it about a couple inches above your crotch.
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Old 11-21-2018, 02:42 PM
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Not sure I understand where you are trying to go from here. If we are looking at the underside of a bowl (all sides curving toward you) and you want the portion by your foot to go away from you, then you are looking at making a reverse, in which case you will want to stretch.
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Shrinking using a stump:
https://www.youtube.com/watch?v=-HAFndATFo4&t=7s

Making a reverse using a stump:
https://www.youtube.com/watch?v=7PlF1BoMCQI

Circular Truss E-Wheel
http://allmetalshaping.com/showthread.php?t=15419
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Old 11-21-2018, 03:13 PM
norson norson is offline
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When I was looking for a stump I finally found an Elm stump from a guy that dealed in firewood. The problem is to get to someone before they cut it to firewood length.
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Old 11-21-2018, 03:48 PM
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Kerry Pinkerton Kerry Pinkerton is offline
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BTW, wheeling will make the panel much easier to work. All the grains in the metal are all screwed up because of the hammering. Wheeling lets them all go back into alignment and relaxes the metal so it's easier to work again.
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Old 11-21-2018, 04:35 PM
RB86 RB86 is offline
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Quote:
Originally Posted by Kerry Pinkerton View Post
BTW, wheeling will make the panel much easier to work. All the grains in the metal are all screwed up because of the hammering. Wheeling lets them all go back into alignment and relaxes the metal so it's easier to work again.
Thanks Kerry. Should I planish it out on the wheel first and then come back to my shaping/forming?

Is it common practice to hammer it out, wheel it out, then hammer more? Or should you save the wheeling until youre pretty sure it's correct?
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Old 11-21-2018, 05:23 PM
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Kerry Pinkerton Kerry Pinkerton is offline
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Quote:
Originally Posted by RB86 View Post
Thanks Kerry. Should I planish it out on the wheel first and then come back to my shaping/forming?

Is it common practice to hammer it out, wheel it out, then hammer more? Or should you save the wheeling until youre pretty sure it's correct?

I find its easier to work if you stretch/shrink, wheel, repeat. Others may disagree. Yes wheeling costs you some of your shrinking because the wheel is basically a stretching machine. That is made up for in ease of working and manipulating the metal imo.



If you were very familiar with a given panel, you could probably stretch/shrink and only planish/wheel once but most humans aren't that good unless they've done many of a given panel or have a ton of experience.
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Old 11-21-2018, 05:34 PM
Peter Tommasini Peter Tommasini is offline
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Quote:
Originally Posted by Kerry Pinkerton View Post
You can Rob but it's not really a novice technique. A couple things to keep in mind.

1- Tuck shrinking really only works well when the panel is fairly flat. Once it gets shrunk on the edges, it's much more difficult to get the tucking forks in place.

2- Therefore, start tuck shrinking as deep as you will think you will ever need. Stretching is easy...shrinking is hard so if you over shrink, you can easily stretch it back out.

3- Shrinking happens in a pie shape. If you want a wedge shaped shrink say 3" deep and you want to shrink 1/4 of an inch 3" into the panel. Think about how much the panel has to shrink on the edge...probably 1" and 1/2" about at about 1.5" in.

4- Finally, the way to shrink deeper into the panel is to make a big tuck and just close the EDGE. Leave the bubble above it. You can then, with practice, drive the shrink inboard.

It might help you to watch this video of my son Kris demonstrating our approach to tuck shrinking... https://www.youtube.com/watch?v=mkaCJ5gC3jI

While you are on youtube you can search for tuck shrinking and there are others. There are lots of ways to do it and folks evolve a method that works for them. If someone is teaching you who says that their way is the only way...find another teacher.

Finally, you mentioned you were hammering out your tucks on the floor. I suggest you at the minimum use a piece of 2x12 until you get a stump. Wood seems to hold the tuck up and keep it from sliding open better. You can do it on concrete but you'll get grit in your panel and spend more energy than necessary.

When you find a stump (call up some tree surgeons...they can't split big stumps and have to pay to get rid of them. If you ask nice, they'll cut it to length for you. You want it about a couple inches above your crotch.
Kerry
I ....DO NOT like to sound that I know it all ! PLEASE KEEP THIS IN MIND before reading the rest
.................................................. .................................................. .................................................. .................................................. ...

Unfortunately that is NOT the way to Tuck shrinking by hand or on a stump

First of all... a tuck can be done on a flat panel and on a bulbous shape,the difference is that on bulbous shape you must use a proper bench dolly,also the tuck must be on the out side of the panel NOT on the inside

second the tuck is closed from the end of the V not the front
and for a much longer tuck....you can initiated it with the hammer and dolly then finished off with the tuck fork which would mean that you can tuck two feet deep or more (if needed) .

When a tuck is made the way shown on the video, there is much more chance to overlap the metal, and it does not put shape needed on the front of the tuck .I am not being critical of your post but simply like to teach the right ways to perform tuck shrinking... YOU HAVE THE RIGHT TO THINK I AM WRONG I AM OK WITH THAT........ if that is the case, simply look at the way the thumb shrinking dies works, on the way in the tuck is made, then the shrinking is started from the back on the way out + When shrinking with a machine (Eckold or others) the shrinking is done by starting at the back, and proceeding towards the edge with heavier and wider area shrinking

Peter
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Metalshaping tools and dvds
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Metalshaping clip on youtube
http://www.youtube.com/watch?v=WEAh91hodPg

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http://www.youtube.com/watch?v=KIpOhz0uGRM

Last edited by Peter Tommasini; 11-21-2018 at 05:53 PM.
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  #10  
Old 11-21-2018, 07:33 PM
RB86 RB86 is offline
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https://youtu.be/FIoge_zNREo

I made another video showing the progress on my fender
And one of my problems with the tuck shrinking.

Thank you all for your input.
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