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  #1  
Old 19-02-09, 05:01
Bob Carriere Bob Carriere is offline
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Location: Hammond, Ontario
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Default Calling sheet metal Guru Barry Churcher...

Good day Barry

On seperate threads you talked about skinning the early cab11/12 doors.....
.....and making end caps for the fuel tanks.

Need to pick your brains as we are in the same area and wayyyy over our heads.

I will be posting pictures of the doors we took apart meanwhile sit down a while..

It seems that the skin on the door is only held in place by the crimped.... no just bent over edges..... with of course a total absence od any kind of paint or preservatives. I have measured the skin at 19 guage and will probably compromise by using a .040 thou sheet, which seems to be a popular size, and which falls between 18 and 20 gauge. [B]What gauge did you use on the doors you worked on.Did you use a pan box brake to form the top edge and prebend the side overlap to 90 degrees before inserting the frame...?

I was going to spot weld the skin but that seems overkill and may leave pit marks. What are your thoughts on using the new 3M sheet metal panel glue to skin the doors?

How did you guys fold over the edges...... light hammer blows....any heat..?

How about the bottom curved section... whcih must first be shrunk to bend the first 90 degrees then stretched to fold over completely... was any heat applied.

Any secrets to keeping the skin tight during the edging process.....

Needless to say I am practicing on a couple of rusted out spare door first.

We have often considered stripping out the fixtures from an old CMP gas tank and bucking a repro on a wooden form...... I have done enough solid wood molds for Joyce's basketry that doing one for the tank woudl not be a problem. The end caps have alwasy been intimidating.

Bob Johnson in Ottawa (famous hot rod shop in little Italy) wants $400 to accurately repro ONE tank.....

Did you have to use a stretching/shrinking tool to form the edge of the end cap..... or just mucho heat and a flame resistant bucking pattern...?

What gauge did you use for the tanks..... mine seem to be 20 or even 22 gauge..... filler is soldered....... How did you reproduce the external dimple for the drain plug and the top side sender.... or did youuse the large brass sender plate of the early tank design....??

I was thinking of doing the bucking on a wooden form and tackweld the end cap as the folding takes place.... take the form out after 3 sides are done... cutout and insert the baffles, spot weld baffles... then close the fourth (back side) and finish with the flat seam clamped and mig weld.....

How did you go about it...?

May have to visit your shop for a consultation or treatment in the future.

Grant as also carefully dismantle a cab 13 door.... what a simple construction after working on a cab 11/12. Mind you the spot welds are a pain.

Have you reskinned a cab 13 door..... and if so how do you reproduce the indented section at the external top of the door...... that ofset is for reinforcement but a bitch to do with our means.

Is your shop equipped with a pan box brake or do you get your sheet metal formed / done at a local fabricator...



So little time so many questions...... that's enough for tonite.

Anybody else which has experience in this domain please share the wealth......

Eager to learn.......Boob
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C15a Cab 11
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Canada
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  #2  
Old 22-02-09, 20:52
Barry Churcher's Avatar
Barry Churcher Barry Churcher is offline
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Location: Castleton Ont.
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Hi Boobee
We used 20 gauge satin coat for the door skins and the fuel tank. The satin coat is a little more expensive but well worth it for rust resistance
although you must use quality primer with it. One of the first projects I did was a front hatch cover for my artillery tractor. A painter friend of mine stopped over to look at my work and said it was a waste of time because of the primer I had used. He proceeded to use a razor blade and peel it off. That was a quick lesson. The ends for the tank were made with heat and a wooden buck with the metal sandwiched between 2 pieces. Bob then drilled through the whole thing in 2 spots
and bolted the big sandwich together. The holes can be welded up later. There is a special spray that is flame retardant for the wood but we didn’t have any at the time. There is a photo on MLU someplace showing the singed bucks. Bob had a die made up for the bead roller
to make a crease along the curved surface on the door bottom. Then it was just hammer and dolly work to finish bending it over, being careful not to mark the outside of the door. We have not done a 13 cab door yet but for the crease in the top we will have another die made for the bead roller. Bob made the bead roller and I will try to get
a photo of it on here sometime. When you are finished with a fuel tank you will see that $400.00 for the tank is not far out of line. It’s a lot of
time. We used as much of the fittings in the old tank as possible.
Cheers,
Barry
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Old 23-02-09, 21:07
Bob Carriere Bob Carriere is offline
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Default Merci Dr. Churcher.

I intend to sandblast the practice door frame and sprya with phosphoric acid. I find it leave a find agressive finish that helps the POR adhere like chewing gum. Flat black POR followed with POR semi gloss Chassis black as a binder coat followed by 2 or 3 34087 od.

On the 20 guage satin.... does the aciod pickling make the 20 gauge stiffer to work than mild steel. Am I looking for trouble to work with 18 gauge...?

I understand the bucking boards but have a hard time understanding how I will be able to shrink the sheet metal around the tight corner curves..? I assume the sheet metal was trimmed to size evenly around the wooden block. I guess doing it is beleiving it..... we sure have enough rusted old tanks for fixtures...... how did you attached the end cap and pipe..... original soldering or fancy mig job......? did you use a sealer inside..? I fear my welding will cause leaks...hihihi..

Would love to see pictures of the bead roller that Bob invented......

Thanks for your guidance........

BooBee
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  #4  
Old 07-03-09, 17:28
Barry Churcher's Avatar
Barry Churcher Barry Churcher is offline
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Hi Boobee
Here is the bead roller that Bob made. You can buy them for not a lot of money but it is more fun to make it and then you can have exactly what you want. It would look better with a CMP wooden wheel.

The second photo is an upcoming project. Thanks to Brian Gough for lending me the left fuel tank for the C15TA. I am missing this one so while I have a sample around we will get it measured up.

The last photo is Bob playing around with the bead roller to duplicate the side of the fuel tank.

Cheers,
Barry
Attached Thumbnails
Bead Roller.jpg   Tank-2.jpg   Tank-16.jpg  
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Old 07-03-09, 17:36
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Barry Churcher Barry Churcher is offline
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This is the first try at duplicating the top of the 13 cab door. We want to make up some skins.
Barry
Attached Thumbnails
First Form.jpg  
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Old 07-03-09, 21:46
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Keith Webb Keith Webb is offline
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Default Amazing!

Quote:
Originally Posted by Barry Churcher View Post
This is the first try at duplicating the top of the 13 cab door. We want to make up some skins.
Barry
That looks great, Barry.

I imagine the inner skin may be more difficult with the circle in the middle.
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  #7  
Old 08-03-09, 00:00
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S LATHERON S LATHERON is offline
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Default 13 cab door skins

Hello,
Over the last couple of summers I have re skinned two cab doors.The original skins were rusted out just above the lower crimped edge and the drivers door in particular needed general renovation
As you said removing the old skin is a pain due to spot welds. These are best drilled out using 1/8 TH INCH DRILL with extreme care. WIRE BRUSH IN CHUCK OF ELECTRIC DRILL TO LOCATE OLD WELDS AND CLEAN ALL OLD PAINT and patience so as not to drill the inner skin other than where the tip of the drill pokes thru on the angled point.
I re skinned doors using steel of similar gauge.
All photos I took for my album were taken with old fashioned film so Ii need to get access to a scanner to transfer the detailed pics.
I placed the old door skin on a pre primer painted sheet of steel, Paint on INSIDE FACE only. the reason why will be obvious later.Then using a 90 degree SET ANGLE and a steel rule, Masking tape and a pencil transferred all dimensions from the old door onto the primer and made a template to trim to size. Cut out the new door skin leaving a generous
amount of metal to form the folded over edges.
Using spare sheet metal as a test piece I then tried to make a metal former with a step in it press the upper door swage line but was not able to exert enough local pressure to get a clean line pressed into the metal.
Forming the body swage line took a lot of effort and a couple of dummy runs with trial and error on scrap metal i worked out the sequence i needed to follow. After all its only 35 years since i did any proper metal work at school.
However my brother in law Ray has a box folder / table with an adjustable clamping blade in his home workshop. His help lining up the metal was a great help. I showed him what i needed to do and I had taken along the old door skin as a pattern /to take measurements.
Taking the measurements from the INSIDE of the top edge.
There are 2 x 90 DEGREE folds and then the SWAGE has two actual folds. Neither of which are a full 90degree bend,We worked out that you need to work from the middle of the door ie this would be the first bend in the sequence IE the lower edge of the bend in the swage.
This is where the painted [ in] side and the plain Outside come into there own, Locate where the lower edge of the swage starts, Place the metal LOWER EDGE OF DOOR [narrow end of door skin] into folding bars with the painted side underneath. Lower top clamp and rigid edge tight onto metal making sure that the door skin is SQUARE to the fold and lock tight in place. Raise the bending bar which is below the steel sheet up till it bends the sheet to a touch over 45 Degrees. So that when you relax pressure it stays at that angle.
Remove the now Bent door skin and turn it over.
Measure the old door skin swage width. approx 1/8 th inch and pencil a line ON THE PAINTED SIDE above the first fold [widest end] Place this end into press SHINY side face down and lock in place using the pencil line as the set point.
Ensure it is parrallel with first fold.
Carefully raised lower bending bar and continue to raise it till the sheet of metal is bent till the second bending makes the sheet stick out level from the folding bar. The sheet will now have a step in it with a slope of about 45 degrees.This is actual swage line.
After this it is a matter of measuring the distance from the top of the swage to the first 90 bend, pencil on paint is first mark or use a sharp steel point to scribe line. Fold and repeat for final bend which will end up giving you a sheet with a 180 DEGREE channel along the top.
Lots of fun fitting the door skin to door inner skin,
You need lots of clamps. A hefty piece of angle iron to hold edges straight edges firm while bending. The inner curve was achieved by cutting a series of V s along the radiused edge to allow shorter bends where I needed to crimp skin in place, A spot weld to hold skin at edges would be a great help. As i have not got this I had to be extra careful, As you crimp the lower edge it pulls the door top edge lower that it should be so you need to be EXTRA careful not to distort the whole door top edge.
Good luck
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