Panel Fabrication Advice

[JonnyAlpha]

Hi;

I am making some repair panels and need some advice.
The first panel I am making is this one:

It is pretty straightforward and has some slight bends along its profile:

I have made a template for the panel by laying a piece of cardboard on it, marking it and cutting it out. I have used the template as a stencil and transferred the shape onto some 2mm sheet metal.

Here is the template and marked sheet metal:

Next step is to cut it out and bend it using the existing panel in place as a guide.

Question:
Based on the technique above once I cut the panel out and shape it using the existing panel once the existing panel is removed will my home made panel fit? Or is there anything else I need to do to take the bends into consideration?

Thanks

 

[the snooper]

leave it slightly long, bend it to shape and if there is any changes due to the bend it wont be too short then trim to suit

 

[JonnyAlpha]

leave it slightly long, bend it to shape and if there is any changes due to the bend it wont be too short then trim to suit

Thanks, in the pic above I have left 10mm at the nearest end, i'll also leave a little extra on the sides just in case. Then once I hack the old one off and test fit the new panel

 

[mike 109444]

Thanks, in the pic above I have left 10mm at the nearest end, i'll also leave a little extra on the sides just in case. Then once I hack the old one off and test fit the new panel

Try NOT to HACK the old one off as you may distort the underlying frame shape. Try and find then drill out all the spot welds around the edges. Genitally prise apart drilled spots and straighten out underlying frame using a straight edge to check before trying your new piece. otherwise you will be clamping and distorting to make it come together.

 

[mike 109444]

Note also that some of the indentations in that panel are there to make the piece more ridge. some are for tooling / location in jigs.
A way to help show up the spot welds is to rub some chalk dust along the area and they should stand out better. They are usually spaced about the same distance along so if you think there should be one then there probable is.

 

[JonnyAlpha]

Try NOT to HACK the old one off as you may distort the underlying frame shape. Try and find then drill out all the spot welds around the edges. Genitally prise apart drilled spots and straighten out underlying frame using a straight edge to check before trying your new piece. otherwise you will be clamping and distorting to make it come together.

I was going to be careful :-)
The piece is part seam welded at the ends and I have noticed a couple of spot welds as seen in the first pic, I guess its also spot welded along the edges. Looks like i'll need to buy a spot weld drill bit or two ?

 

[JonnyAlpha]

Note also that some of the indentations in that panel are there to make the piece more ridge. some are for tooling / location in jigs.
A way to help show up the spot welds is to rub some chalk dust along the area and they should stand out better. They are usually spaced about the same distance along so if you think there should be one then there probable is.

I will hopefully be replicating the indentations, thanks for the chalk tip, i'll wire brush everywhere i suspect spot welds too.

 

[500e]

Another way to find spots is with soft disc grinding wheel color changes due to different thickness, if you are good with grinder you can remove closing plate completely without damage to lower structure

 

[the snooper]

Try NOT to HACK the old one off as you may distort the underlying frame shape. Try and find then drill out all the spot welds around the edges. Genitally prise apart drilled spots and straighten out underlying frame using a straight edge to check before trying your new piece. otherwise you will be clamping and distorting to make it come together.

I don't think you should try the above highlighted part, I would imagine it to be very very painfull

 

[Robotstar5]

Genitally prise apart drilled spots....

Must have some b4lls to try that!

 

[JonnyAlpha]

Well I managed to successfully get the panel off, did a full post on RetroRides its about half way down page 21.

Here's the link

 

[JonnyAlpha]

OK as well as the advice I asked for in the post I made on Retrorides linked above, I need some more help with measuring and marking out repair panels.
I have spent the afternoon making a template of the second piece to be made and have read through the 'Making Panels' thread on Retrorides regarding making templates and repair pieces but could not work out how to reliably take measurements from the piece that needs to be repaired and transpose them onto sheet metal, so not knowing any other way I decided to make a cardboard template.

First I marked the main curve by placing a piece of cardboard at right angles to my first repair plate clamped in place then I transferred this curve onto another piece of cardboard that would be used to make the main template. I then marked the entire top curve onto my template and used this as a start line to mark measurements taken from the piece to be replaced.

I then made a few folds in my cardboard template and started to fit it into the recess of the panel to be replaced, making the template did demonstrate the metal would react on the curves, on the upper curve the cardboard needed to be cut and overlapped and on the bottom it had to be cut and left gaps. So to make these edges i'll do the same with the metal piece and weld the cuts?? Or attempt to shrink (fold in) the top edge and stretch the underside edge.

The template above does push back and almost hide the top edge.

Basically I have ended up with a template of the inside measurements of the panel to be replaced, this started to confuse me as to how to correctly transpose these measurements onto my sheet metal and end up with a repair piece that would fit? My thoughts were that if i did not make any allowances for this all I would end up with is a repair panel that would fit inside the piece being repaired and therefore end up too small!!! Do I simply add the width of the metal to my measurements??

Here's the template laid out on my sheet metal:

I started to mark out the rest of the panel but stopped once I realised my problem.
I am know going to read through the relevant sections of this thread and see if I can figure it out?

HELP PLEASE!!!

 

[mike 109444]

X Is the key dimension. By rights you would measure the radius in the corners and use bending calculations for the thickness of the metal and taking a center line through the sheet metal as the reference etc etc...
Easer just to allow about 1 mm top and bottom of the X dimension of your template (assuming 2mm sheet being used) Don't forget your card template will have a much sharper corner than the steel will (if you folded the steel like the card it would crack!) So if the dimension X on the card (when folded) is 25mm then mark a strip 27 mm wide. I know it is tapered but just allow the same + 1mm top and bottom along the taper. Also worth adding a bit on the ends for the shrinking and stretching
Lets hope the spell checker has not stuffed this up !!.

 

[brokenbiker]

wot he said ^ explained it better than i would have

 

[JonnyAlpha]

X Is the key dimension. By rights you would measure the radius in the corners and use bending calculations for the thickness of the metal and taking a center line through the sheet metal as the reference etc etc...
Easer just to allow about 1 mm top and bottom of the X dimension of your template (assuming 2mm sheet being used) Don't forget your card template will have a much sharper corner than the steel will (if you folded the steel like the card it would crack!) So if the dimension X on the card (when folded) is 25mm then mark a strip 27 mm wide. I know it is tapered but just allow the same + 1mm top and bottom along the taper. Also worth adding a bit on the ends for the shrinking and stretching
Lets hope the spell checker has not stuffed this up !!.

Mike;

Thanks for taking the time to sketch this out, a picture paints a thousand words as they say. I think I get it now. I'll be using 1.2mm sheet metal for these next pieces but will adjust your advice accordingly. I'll post back the results :-)

 

[mike 109444]

Jonny not sure if you have caught the "Wheeler Dealer" program on Discovery Turbo but they (Mike and Edd) have been doing up a Mini Moke Which you no doubt know is based on the Mini! I usually catch there programs while on the computer and lo and behold they were replacing the rubber cone suspension with spring type as an up grade. Never worked on a mini (lucky me ) So did not even know what they used. You might find the show on You tube as I think some are on there. Seen your post on Retro Rides ref your suspension.
Keep up the good work.

 

[JonnyAlpha]

Jonny not sure if you have caught the "Wheeler Dealer" program on Discovery Turbo but they (Mike and Edd) have been doing up a Mini Moke Which you no doubt know is based on the Mini! I usually catch there programs while on the computer and lo and behold they were replacing the rubber cone suspension with spring type as an up grade. Never worked on a mini (lucky me ) So did not even know what they used. You might find the show on You tube as I think some are on there. Seen your post on Retro Rides ref your suspension.
Keep up the good work.

Mike - Thanks for the encouragement, found the Wheeler Dealers programme and watched it never realised Mokes where an off the shelf design. Great little motors.

 

[JonnyAlpha]

OK - I have started to form the second repair piece, bending the straight folds was simple, trying to bend the curved folds proved a bit trickier as I could not do it in my bender due to the size of the panel, maybe if I had started with the curved folds first it may have worked but I needed to get the straight folds done to ensure the curved folds were correct as the piece I have cut off had already been repaired and was distorted in that area?@?@??@

Anyway here's the tricky bit, I decided to use one of my dollies which luckily was about the same radius:

Any tips on doing this better for the next two?

I then measured and marked the bottom fold and managed to start it off in the bender but due to the close proximity of the two folds could only bend to about 45 Degrees. I had to then clamp the piece to my workbench and using a piece of scrap sheet about 5mm thick wedged into the fold I managed to tap the remainder of the fold. Sorry no pics of how I did it but again any tips on bending close folds would be appreciated (The folds in the picture below to the RH side of the Mole Grips on the left).

Here's the panel so far clamped into place:

Now that I have the end folds done i'll now trim and joggle the ends so that the repair piece can fit into its correct position at each end before I tackle the complicated curved and shaped section?

 

[Wedg1e]

Mike - Thanks for the encouragement, found the Wheeler Dealers programme and watched it never realised Mokes where an off the shelf design. Great little motors.

Wasn't the Moke designed to be an air-portable or parachutable fast transport for squaddies, like a Jeep but using a lot less metal and no 4x4
Citroen did a car called the Mehari which I think had the same concept.

 

[mike 109444]

If you had done the smaller fold first then using a piece of packing (blue bit in pic) in your folder then do the bigger one. The metal being folded is the red bit. failing that search on forum for "shrinking" and "stretching".
Yer Doing well so far Just remember people do (or use to) 4 year apprenticeships in sheet metal working so it takes time to get to grips with working the steel.