Help copying 1/72 scale parts to fix incomplete kits

[Illusive]

I've got a 1/72 Pz.4 from UM (https://www.scalemates.com/kits/um-544-sdkfz-161-pzkpfw-iv-ausf-f1--1306237) <— that one. Apparently it is incomplete: missing half the roadwheels and one idler (? spindly wheel that isn't a sprocket). Parts don't look like cut off and one leaf spring already almost broke off a sprue by itself. Given the size and thinness of parts, how better to go about copying required pieces?

Edit: asked manufacturer about spares and answer was silence, so copy it is.

 

Apart from that I'd also need a copy of an 1/72 Airfix Bf.110 Trop. canopy from that other thread of mine. Both times Airfix allegedly sent me the part(s) nothing came. Fine, I'll get another kit, copy its canopy and make a night fighter out of a spare one. There is also a ≈50% cheaper Hobbyboss offering that should, hopefully, be a match. Still, if spending money on a kit, I'd like to keep it buildable rather than assorted plastic parts.

Edited April 24 by Illusive

[Rob de Bie]

The easiest and cheapest (by far) way is to buy an extra kit! But of course resin casting is more fun. You could take a look at the thread 'Vacuum resin casting tutorial' to see how I do it - it's no use repeating all that here. But I will show a teaser photo:

 

 

Rob

[Illusive]

9 hours ago, Rob de Bie said:

The easiest and cheapest (by far) way is to buy an extra kit!

Easiest? Yes. Cheapest? Depends... I already have two-part (supposedly non-yellowing) epoxy and casting silicone leftovers from other projects both completed or shelved. And no vacuum / pressure pot naturally

 

Is it as fun? Not really

 

What if the sprue piece to be copied is placed tilted with sprue gates as vertical channels and extra wax (?) runners used to mould channels supplying resin to lowest part of a mould first? That would work?

[Rob de Bie]

18 minutes ago, Illusive said:

What if the sprue piece to be copied is placed tilted with sprue gates as vertical channels and extra wax (?) runners used to mould channels supplying resin to lowest part of a mould first? That would work?

 

That sounds like a classic method, with a 'J' shaped feed channel and several air vent channels, in a two-part mould. I can recommend  this YouTube channel for that:

 

https://www.youtube.com/@RobertTolone/videos

 

Rob