All MetalShaping

Go Back   All MetalShaping > General Metal Shaping Discussion > Basic questions and answers
  Today's Posts Posts for Last 7 Days Posts for Last 14 Days  

Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 03-29-2019, 10:46 AM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

Ok, I've restarted a new piece, and documented each step. I took the flange out of the original and tried to make due, but I was afraid that flanged area was too out of wack with my various shrinking/stretching.

I have stretched the corner with all my might using the big blocking hammer. Notice both the old and new curve upward towards that corner.

I also developed that same hump in the middle, like the other, so I over blocked the sides to counter.

IMG_20190329_101931583_HDR.jpg

IMG_20190329_102443144.jpg

IMG_20190329_103054036.jpg

IMG_20190329_113819834.jpg
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch
Reply With Quote
  #12  
Old 03-29-2019, 10:54 AM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

See the curvature? I can't quite figure how to fix that. Those lines were straight when I drew them, and I really tried to pay attention and evenly block.


IMG_20190329_114942198.jpg

IMG_20190329_114921074.jpg

IMG_20190329_114840412.jpg
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch
Reply With Quote
  #13  
Old 03-29-2019, 11:35 AM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

I have yet to tip the edge on the new one, but as you can see it's curved just like the previous one. Boy I'm worn out! (New piece in front)

IMG_20190329_123202831.jpg
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch
Reply With Quote
  #14  
Old 03-29-2019, 01:02 PM
crystallographic crystallographic is offline
MetalShaper of the Month October '14 , April '16, July 2020, Jan 2023
 
Join Date: Dec 2010
Location: Western Sierra Nevadas, Badger Hill, CA
Posts: 4,388
Default

Quote:
Originally Posted by RB86 View Post
See the curvature? I can't quite figure how to fix that. Those lines were straight when I drew them, and I really tried to pay attention and evenly block.


Attachment 52054

Attachment 52055

Attachment 52056

Hi Rob,
What you see is normal, as the metal flows into a new shape dragging the lines along with it.
After you get your part to good shape and fit - then smooth it out.
Trim the edge so it lays flat on the table.
Then scribe off your flange setback, using the table top as takeoff.
Then whang over the flange.
__________________
Kent

http://www.tinmantech.com

"All it takes is a little practical experience to blow the he!! out of a perfectly good theory." --- Lloyd Rosenquist, charter member AWS, 1919.
Reply With Quote
  #15  
Old 03-29-2019, 01:58 PM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

Quote:
Originally Posted by crystallographic View Post
Hi Rob,
What you see is normal, as the metal flows into a new shape dragging the lines along with it.
After you get your part to good shape and fit - then smooth it out.
Trim the edge so it lays flat on the table.
Then scribe off your flange setback, using the table top as takeoff.
Then whang over the flange.
Hey Kent. Thanks for the reply. So here's my challenge...

The only piece of critical information I have is that flat template which gives me the perimeter where the flange must lay.

IMG_20190329_144542394.jpg

The 2 inch depth is that maximum amount of room I have to work with where this piece will be. So I just drew a radius by hand and cut it out of cardboard.

15538855731304532683526205696462.jpg

I'm continuing to make sure that radius gauge fits. As I slide towards the corner, it still fits fine, but the line curves up.

I started with excess material, and as I stretched and stretched, I trimmed down to the edge of my flange line. I dont have any more material to trim away and "straighten" it now. Did I go wrong there?

The hard part is, regardless of the shape and uniform radius I might achieve, that flange has to lay right on my template in the same path.

For what it's worth, for experimentation I pie cut the corner of my previous piece, mig welded it, then trimmed as straight a line as I could, then tipped it. The mig area was too stiff to tip, even hammering it.
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch

Last edited by RB86; 03-29-2019 at 02:01 PM.
Reply With Quote
  #16  
Old 03-29-2019, 05:41 PM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

I'm trying a new method. I cut out my blank. Keep in mind that area of the flange on my blank has to remain in position against the template before I hammer anything right? And, when I start blocking the inside perimeter of the flange, that creates tucks, which shrinks that area, sortve throwing my "flange track" off course. So this time I took a planishing hammer and pre-stretched the flange, then blocked the inside perimeter, really focusing to lift the corner (the part that keeps dipping). Then I go back and restretch the flange, keeping it tipped from the very beginning.

A small bit of blocking, keeping the panel open, then back to re-stretch.

So far is the closest I've gotten. I'll update more later.
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch
Reply With Quote
  #17  
Old 03-29-2019, 05:57 PM
Peter Tommasini Peter Tommasini is offline
MetalShaper of the Month May 2013, Dec 2013
 
Join Date: Apr 2011
Location: Melbourne,Victoria, Australia
Posts: 7,750
Default

Rob
unless I misunderstood ????
I would simply mark the corner out, then tuck shrink the corner(only) turn the two connecting sides down as you doing the tucks a bit at the time on a pipe with the right size radius ,that will leave the sides flat ready to turn the flanges outwards ,then fill in the center to suit on the wheel or by hand (if needed) . Only light blocking and blending would be needed to blend the corner with the rest of the 2 sides turned radius
Peter.

EXPLANATION on your problem
1. when blocking in that mater the two sides will shrink and become shorter there for changing the draw line (which must be re drawn back flat)

2. knowing the above factor ..more material must be allowed

3. blocking in that mater the center will cave in, meaning a lot of stretching in the center part of the panel, and possibly create fullness when not needed ( if that happens you need to stretch the edge and by lifting the panel on the top wheel let the center shape out to the now stretched edge (this exercise can be done a few times)
__________________
P.Tommasini

Metalshaping tools and dvds
www.handbuilt.net.au

Metalshaping clip on youtube
http://www.youtube.com/watch?v=WEAh91hodPg

Making Monaro Quarter panel:
http://www.youtube.com/watch?v=KIpOhz0uGRM

Last edited by Peter Tommasini; 03-29-2019 at 06:40 PM.
Reply With Quote
  #18  
Old 03-29-2019, 07:18 PM
RB86 RB86 is offline
Member
 
Join Date: Nov 2018
Location: Charlotte NC
Posts: 119
Default

Quote:
Originally Posted by Peter Tommasini View Post
Rob
unless I misunderstood ????
I would simply mark the corner out, then tuck shrink the corner(only) turn the two connecting sides down as you doing the tucks a bit at the time on a pipe with the right size radius ,that will leave the sides flat ready to turn the flanges outwards ,then fill in the center to suit on the wheel or by hand (if needed) . Only light blocking and blending would be needed to blend the corner with the rest of the 2 sides turned radius
Peter.

EXPLANATION on your problem
1. when blocking in that mater the two sides will shrink and become shorter there for changing the draw line (which must be re drawn back flat)

2. knowing the above factor ..more material must be allowed

3. blocking in that mater the center will cave in, meaning a lot of stretching in the center part of the panel, and possibly create fullness when not needed ( if that happens you need to stretch the edge and by lifting the panel on the top wheel let the center shape out to the now stretched edge (this exercise can be done a few times)
There you go making things simple again I will certainly try that on lucky #4

I find that I continue to get stumped on something needing stretching or shrinking. When I see that curved flange my mind argues - Maybe its too much material in a confined area and thats why its bulged up and therefore it needs shrinking. OR its drawn too tightly being pulled up like that, and it needs more material to relax back down. Its funny how simple it is and isnt at the same time for us amateurs.

Thank you Peter
__________________
Rob
1950 Cadillac
1956 Cadillac
Looking to build my own car from scratch
Reply With Quote
  #19  
Old 03-30-2019, 09:06 AM
mark g mark g is offline
Metal Shaper of the Month, April 2011, December 2012, May 2016
 
Join Date: Nov 2010
Location: Southern VT
Posts: 362
Default

I'm estimating that much as 2/3 of each side of the part can be gotten with no blocking. Choosing the hammer to round up the edges where blocking is not needed is the main problem I see. That's where the stretching that's working against you is coming from.
__________________
Mark

www.markgoodenough.com
Reply With Quote
  #20  
Old 03-30-2019, 11:34 AM
norson norson is offline
Member
 
Join Date: Nov 2010
Location: Portland, Or.
Posts: 400
Default

I think your main problem is you are drawing your lines, banging the hell out of it and then expecting to still adhere to your lines. Forget the lines. Form the panel including the smoothing, THEN draw your line at the tipping point based on the formed (upper?) portion of the piece. This may mean placing the dished portion on the table and mark the piece one or two inches above the table. then tip the edge at the line and it will be flat.
__________________
Norm Henderson
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 On

Forum Jump

All times are GMT -5. The time now is 12:56 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.