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  #1  
Old 03-28-2019, 06:55 PM
RB86 RB86 is offline
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Default Can you guys help me please

Im frustrated at this point. I need to make a simple piece (it's never as simple as it seems).

You'll see the basic idea. My flange won't lie flush. I've tried shrinking/stretching the flange itself, I've tried hammering the radius on a post dolly to stretch. I've tried stretching out the flat area.

I drew my lines for the flange, and the apex of the curve, and blocked it all into the sandbag. What did I do wrong? Did I over block that area where there's a hump?

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Old 03-28-2019, 08:12 PM
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Steve Hamilton Steve Hamilton is offline
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Usually I would not tip the flange until after the panel was completely shaped and smoothed out.

Yes you did create the hump by stretching too much in the radius.

To correct that I would bend the flange from 90* back to flat, then linear stretch the area between the apex and the edge. More stretch close to the edge and less near the apex. After you get the panel edge straight then the flange can be tipped back to 90*

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Old 03-28-2019, 08:19 PM
Ken Hosford Ken Hosford is offline
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In my opinion
you are not far off , I would try clamping to flat surface and using a 4" brick chisel with a rounded edge pound down the corner.. I think you over stretched the top causing it to banana so pound it down .
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Old 03-28-2019, 08:52 PM
RB86 RB86 is offline
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Thank you guys...

I made a quick video to explain more for whatever it's worth.

https://youtu.be/LJfRE-XA2sU
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Old 03-28-2019, 09:14 PM
steve.murphy steve.murphy is offline
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I think you would tip the flange last like Steve mentioned. I think the flange you have put on the first part has locked you into the shape you have. You could cut out the flange to see if it frees it up again as a learning experience.
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Old 03-28-2019, 09:15 PM
BTromblay BTromblay is offline
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Hi,

I watched your video and this is my recommendation. With a hammer and dolly, take the tipped edge back off. Meaning, tip the flange back to how it was before you tipped it. Block and finish planish your part to match your profile gauge. Then re-mark and tip your part flange.

Hope it makes sense.

B
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Old 03-29-2019, 03:25 AM
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neilb neilb is offline
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looking at the first pic, shrinking or stretching that flange will only make the flange go in or out, not up or down. down is what you are seeking.

when you block out shape on a sand bag, the metal stretches but it pulls from all around it. if you hammer on a hard surface (dolly) the metal stretches where you hit it, it doesn't pull material from all around the strike point.

my guess is you have tipped the flange and then blocked out more shape? that has then lifted the flange where it doesn't meet the flat surface you have it sat on.
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Old 03-29-2019, 07:34 AM
mark g mark g is offline
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Hi Rob,

That's an interesting shape with an interesting problem. It's almost two simple rolls that meet at the rounded corner, so much of what shaping that is required would happen near the corner and taper out evenly as you worked away from the corner, where it becomes more of a simple roll with an added flange. The problem is that for that all to happen, the shaping would be done near the corner first then the rolling into "arrangement" where the shaping tapers out would be done next, flanging last. As it is now, the flange holds the metal in one particular arrangement and prevents the simple bending of the part since that action would change the shape of the flange in the corner. I think the blocking has been carried a little too far from the corner and not tapered out to suit the shape. If you needed to flange first for some reason, it might be advisable to secure that quality of flatness by fixing it to a flat surface before moving ahead with more shaping: ie a plywood panel with the part shape cut out so you could work from inside the shape, and limit the metals reaction to further shaping.

If you would model the part and pull a pattern from that, you would be miles ahead of knowing where to block vs roll, since the pattern would flatten out where it was able and give you a good idea where and how much to taper out the shaping. Hope this helps -Mark
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Old 03-29-2019, 07:39 AM
RB86 RB86 is offline
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Thanks guys. I'm going to try and reverse the flange, get it fitting my profile better and then re-tip.

This time around, if a tuck happens I'll shrink it on the stump.

I'm not trying to recreate a part, but rather create a new one. The only thing it really needs to maintain is the flange. That must match my template. The profile gauge was hand drawn, I just want it about 2 inches deep.

I'm hoping the flange area doesn't change when I reblock after tipping back up. We'll see.

Thanks
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Old 03-29-2019, 07:42 AM
RB86 RB86 is offline
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This is going on the front of a 66 Ford truck with a 2013 mustang engine. The front rad support was cut out to clear cold air induction, but we were worried about rain, so this is sortve an open scoop that would deflect rain and still allow air up through the grill.
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