Have I been doing it wrong all these years?

Every time I build a truck or whatever which has leaf spring suspension, the manufacturer always has the mould line running along the leaves. For 40 years I have carefully removed the mould line and scraped the leaves clean. Now, I was leafing through the Haynes Manual on the Flak 88 and come across this picture. Have I been doing it wrong all these years; should I have been adding welds?

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God, that’s weird! Never seen leaf springs like that before!
Ken.

There are several different types of leaf springs; some show a ridge and others don’t. It is an artifact of the manufacturing process. If it was a weld there would be a chance of the leaf splitting, so it isn’t that.

Opel Blitz

One issue to fix on “all” kits is the ends of the individual leaves. Mold technology results in the ends being rounded

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Probably a casting seam.

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Crap! Next we’re gonna find out tank gun barrels really have mold lines too!

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Maybe a stiffening or reinforcing ridge on each leaf?
:smiley:

Well, at least I’m not the only one stumped! In the original photo in the book (sorry mine was taken with a phone) it’s pretty clear that they are welds. The only thing I’ve seen similar is the weld when you join a band saw blade before grinding it smooth. If leaves show a ridge other than a weld, surely it’s not a casting mark?

How It’s Made (tv show)
Leaf springs

There’s no denying the OP photo showing ridges, but I couldn’t find anything about them.

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The groove on the bottom fits on a ridge on the top of the next spring. It is designed to keep the springs aligned and stop twist. It was quite common on German heavier vehicles. The SdKfz 9 has the same feature:



So a seam on the top is correct inc some cases…but that means a groove is needed under…

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The timing of your post couldn’t have been better. I’ve got a Famo arriving today! Saves me the hassle of smoothing those parts. :wink:

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Wow, that’s something to think about! Fortunately not all were the same :slight_smile:

T-26 for example was plain:

But yes, I bet I have done it wrong a number of times during my modelling life… assumptions are not always safe.

I see another niche for the rivet counter personalities, groovy …

I presume that the material used for the spring leaves was the same in all the leaves so the longest one needs a groove on the visible side …

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Definitely a case of bringing documentation to a contest.

Another case of no weld line.
http://svsm.org/gallery/ZiS-5V/1_P3060107?full=1

Nice video, now I just need one on how to make 1/35 springs.

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A variation on a Hotchkis spring
image
from Leaf spring | Tractor & Construction Plant Wiki | Fandom

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The operative keyword is: “tedious”

I had to build a new front spring for a 1/35 GAZ-66 from Eastern Express (I lost the kit part somehow).
Luckily Evergreen had styrene strips that were close enough in width and thickness so I didn’t have to cut strips. Make the longest leaf way too long and glue the ends down over a form (elliptic) made from thicker styrene (CD-cases for instance). Mark the centre and start gluing the shorter leaves on top of the longest.

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That Hotchkiss spring would need to be done from PE-strips with a half-etched groove.
Assembly would be the difficult part …

er…Pass!

If you were to do that on something barely seen, I would know which side of the debate on ‘dedicated’ vs ‘barking mad’ I would lean toward.

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Woof, woof, wooof …

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