S.M. U-1 (a new RC project)

[DrSchmidt]

The backsides of the four molds is still open, just the sanded filling medium exposed to the open. So the next step is to apply a lid. Basically one takes a coated wood board, next one applies some parting wax, then one laminates the same GRP layers onto the board that were used to make the mold, then one applies a coupling layer of resin mixed with cotton flakes onto the backside of the mold, filling the gaps of the porous filling medium, and than one presses the mold onto the GRP using a plenitude of c-clamps. Done....

[He Who Shall Not Be Named]

A well fought battle, sir!

[DrSchmidt]

Opened the mold and removed the master of the U1. Did not go smoothly as the master got stuck, but in the end some persuasion with a hammer helped. Molds are O.K., not perfect, but I‘m confident that I‘ll be able to produce nice hulls out of it. Next is the application of the GRP backside and then we're in busyness.

[DrSchmidt]

Only when everything went well....still enough failure scenarioss. A stuck master, air bubbes, something got too hot dring curing....only when the master is out and all the seems look good, I'll be happy.

[redboat219]

This should be playing in the background https://youtu.be/e-QFj59PON4?si=idU9tC--x4lXW759

[DrSchmidt]

After a few weeks, 7 kg epoxy resin, 2 kg of surface resin, 2kg of glass fiber fabric and 22 liters of filling medium, the master of the S.M. U1 submarine, Germanys first military sub from 1906, is firmly entombed in its mold. Doesn’t look spectacular, but when everything went well, these will be excellent and robust molds to make a few hulls from. I‘ll wait a few more days to give everything a bit more time to cure before the most exciting part of the process is due: the opening of the molds.

[DrSchmidt]

History repeating...the same sermon for the fourth and final quarter of the mold. Setting the Indexing pins and thread insets, building the wooden box, putting down in the surface resin and then, while the resin still is sticky, apply cotton flakes to create a coupling layer for the GRP that will be laid down later.

[DrSchmidt]

Sanded flat, box removed, and the remaining quarter of the master cleaned. Seams look good. So ready for the final lap…

[JHapprich]

Weather conditions should be ideal at your place, too!

Looking forward to seeing pictures of the first hull!

Jörg

[DrSchmidt]

2,5 hours of laminating and 2 kg epoxy later, the third quarter is done....one more to go:

[DrSchmidt]

Set up the third quarter of the mold. I'll put down the surface resin tomorrow and then I'll laminate the box later this week.

[DrSchmidt]

Some more...

[DrSchmidt]

Placing the PE parts on the CAD-Model...already found some mistakes. Good check before investing money in the fabrication of PE.....

[DrSchmidt]

Work on the molds has to wait while I'm waiting for new materials, but I can use the time to work a bit on the PE sheet that I plan to make for the detailing of the boat....

[DrSchmidt]

Setting up the vertical parting plane for the lower two halves of the mold. Tricky job, but if one got the upper half straight, this step is not too challenging.