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, thatā€™s weird! Never seen leaf springs like that before!
Ken.

There are several different types of leaf springs; some show a ridge and others donā€™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 isnā€™t that.

Opel Blitz

One issue to fix on ā€œallā€ 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 weā€™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 Iā€™m not the only one stumped! In the original photo in the book (sorry mine was taken with a phone) itā€™s pretty clear that they are welds. The only thing Iā€™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 itā€™s not a casting mark?

How Itā€™s Made (tv show)
Leaf springs

Thereā€™s no denying the OP photo showing ridges, but I couldnā€™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 casesā€¦but that means a groove is needed underā€¦

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The timing of your post couldnā€™t have been better. Iā€™ve got a Famo arriving today! Saves me the hassle of smoothing those parts. :wink:

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Wow, thatā€™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 lifeā€¦ assumptions are not always safe.

I see another niche for the rivet counter personalities, groovy ā€¦

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 ā€¦

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Definitely a case of bringing documentation to a contest.

Another case of no weld line.

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: ā€œtediousā€

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 didnā€™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 ā€¦

erā€¦Pass!

If you were to do that on something barely seen, I would know which side of the debate on ā€˜dedicatedā€™ vs ā€˜barking madā€™ I would lean toward.

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Woof, woof, wooof ā€¦

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