Re: Straightening a sheet of metal, how!

[Yevgeniy]

Hi all,

I would like to ask scratchbuilders experienced in working with metal in sheets - litho and the like - how do you straighten it in case you got it distorted or wavy?

I got a sheet of aluminium thickness 0,1 mm but it is not straight. I straightened it roughtly using an edge of the table (glass) just pulling it over the edge of the table (got this tip from cardbuilders - they straighted self-made cardboard this way). It worked more or less OK and it is almost straight so I can use if for laminating ship structures made of thick cardboard which are straight so there is no visible distortions of metal.

However if I need a thin wall - as for example walls of an open wheelhouse - I can not glue this aluminium sheet on cardboard otherwise those walls will be too thick. So I need very straight piece of metal of approx. 1 cm in length and approx. 1 cm in height.

How can I straighten such sheet of aluminium (0,1 mm thickness) and have at lease required areas perfectly straight?

Thank you in advance.

Yevgeniy

[Neptune]

Hmm, perhaps put it between two wooden or steel plates and slam the top plate with a hammer? Not experienced in this, but I don't see too many alternatives and given the size of the required item...

[Yevgeniy]

Thank you, Neptune, I tried slamming it with a hammer between two plates of thick metal but as I found aluminium foil is 'springy' so it returns to original shape after slamming

The whole 'sheet' is approx 20X10 cm (I will answer the riddle I gave in my post V106 in 1:200 - it is aluminium of beer can , painted side sanded so there is not paint)and I can straiten it before cutting out necessary fragment. As I said I straighten it roughtly by pulling over the sharp edge of the table several times (from both sides) and it gets 80-90% straight. However when I can a fragment it is obvious that metal has small waves/bumps etc which it gets after straightening over the edge of the table...or fingers )

When I glue it (laminate) to cardboard it is 100% straight. However if I can not use cardboard because I need a thin wall (as those of a wheelhouse) I need some other way to straighten it.

Will have to experiment...

Yevgeniy

[Neptune]

I think that is caused by the construction of the can itself then, the metal is in that shape and won't be turned flat without heating. I suppose heating it with a torch or lighter and then slamming it could be more succesful. You'll have to heat it until the internal structure of the aluminium itself changes, otherwise I think it won't be really possible to straighten it entirely.

And what about pressing it between pieces of decking on your model itself? Perhaps it'll stay straight when you do that? Make your deck out of two parts, say left and right part and then stick the aluminium between the two.

[Dave Wooley]

Thank you, Neptune, I tried slamming it with a hammer between two plates of thick metal but as I found aluminium foil is 'springy' so it returns to original shape after slamming

The whole 'sheet' is approx 20X10 cm (I will answer the riddle I gave in my post V106 in 1:200 - it is aluminium of beer can , painted side sanded so there is not paint)and I can straiten it before cutting out necessary fragment. As I said I straighten it roughtly by pulling over the sharp edge of the table several times (from both sides) and it gets 80-90% straight. However when I can a fragment it is obvious that metal has small waves/bumps etc which it gets after straightening over the edge of the table...or fingers )

When I glue it (laminate) to cardboard it is 100% straight. However if I can not use cardboard because I need a thin wall (as those of a wheelhouse) I need some other way to straighten it.

Will have to experiment...

Yevgeniy

Hi Yevgeniy I shall post up some photos that may help.
Dave Wooley

[Dave Wooley]

Hi Yevgeniy Litho plate is very malleable . it can be crumpled yet straightened
back to its original form very easily by rolling it around a section of tube .
A section of un-crumpled litho

The same section crumpled out of shape

When thumbed and rolled around a tube it can reform back to its original shape , a flat sheet.

Re-formed

Hope this helps
Dave Wooley

[Yevgeniy]

Thank you, Dave, I will try it.

I was also rolling it but in order to have a curve when needed on superstructure. Somehow I missed an idea that in the same way I can straighten it.

Thank you again.

Yevgeniy

[commodore4]

YEVGENIY! Hi, I have done construction with (GASP!!!) beer cans before and found a good way to straighten the metal out.Go to a thrift store(GOODWILL,St. VINCENT DEPAUL) or whatever you have where you live.Buy two full size rolling pins that bakers or homemakers use.Go to the lumber store and get a 4 foot section of 1x4. Now take the 1x4 and cut it in half.Sand the edges (no one likes splinters)Drill holes in both pieces that will allow thw rolling pins to lightly touch each other.Now get some craft foam.It,s about 1/16 of an inch thick.Glue this on the surface of the rolling pin and don,t leave any spaces.Now put the rolling pins and 1x4 pieces together with some fence wire.Take one end of one rolling pin and put a "T" type handle or a crank type.Now feed the aluminum through it.It will straighten out brass, aluminum and even very thin steel(early red bull cans)You will find it useful for curving sheet plastic too. commodore 4

[Yevgeniy]

Reminds me a gadget on old washing machine (of 80s type) which my mother had for squeezing water out of clothes after machine wash. Two rollers e (same diameter as baker's roller pin) with a handlle

I may try this gadget a little later - currently I drag that aluminium sheet over the sharp edge of a table (covered with a piece of glasss) several times - it works so-so so I am thinking of other ways so I am very grateful for your advice. Dave's suggestion above also works - however may be it works better with litho than with aluminium from beer cans (or Dave hands are needed to do that properly ) - with me it is still far from perfect.

Cheers,

Yevgeniy

[commodore4]

YEVGENY hi: I do believe that,s where my idea came from.I seem to remember my grandfather using grandmother,s old decrepit wringer to straighten a piece of metal to fix a spot on his car fender!The thing sure worked well until he caught his tie in it! The next time I saw it it was in pieces. oh well! Funny how something like that can color one,s thinking so many years later. commodore4

[Yevgeniy]

The thing sure worked well until he caught his tie in it!

Commodore4, sure I can understand that and his feelings !

Cheers,

Yevgeniy