My second Unimould -- Asymmetric BMW windscreen ..

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My second Unimould -- Asymmetric BMW windscreen ..

Author	Message
Dravis	Dravis posted 9 Years Ago HOT Topic Details
Group: Forum Members Posts: 592, Visits: 1.9K	Hi All! Currently I'm working on a project of "customizing" an 1980-something BMW K75 "flying Brick" into something a bit more "interesting" This among a lot of other things means removing most of the extremely heavy plastics on the "donor" and skinning a lot of the plastic that goes back on-- (XCR Coating Resin makes this almost a pleasure, even though I'm not very fond of skinning ) The headlight of the old "Rubber Cow" / "GummiKuh" is replaced by a new item from a GS650 .. an assymetric design with a big dipped beam light and a smaller high beam. To match this I made a plug for a new short / stubby windscreen (usual methods: High Density foam, Pattern fill etc .. ) shaped by hand .. From this I made my second Unimould- mould .. Which went very well... Infusion .. First part out of the Mould .. Stripes slipped .. bummer .. "Orange" kevlar becomes much darker in colour when in resin ... As can be seen -- print through from the 3D core .. and some pinholing at the edge of the core .. and the blasted tow stripe moved ... Next one will be without 3D core (not at all needed, just in there to give it a try .. ) Stack is 200 gsm pw ... 2x325 gsm Satin weave .. crossed .. 3D core between the 325 Satin weaves .. Stripes are EC "orange Kevlar mix" and flat tow .. Notice that the Orange Kevlar is not at 45 Degrees .. ??? ... "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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Fasta	Fasta posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 468, Visits: 3.5K	You should try using some soric instead of the 3D core. Would be perfect for a small shaped piece like that. Fastacraft Facebook page
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Dravis	Dravis posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	Hi Fasta, Yeah, If the new layup with no core becomes to flexible, I'll try the 2 mm Soric I've got .. But, it's not a component that carries any load at all except for the wind pressure.. Sustained riding above 140 km/h is probably not really done on a bike like that with its new wide bars .. "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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Hanaldo	Hanaldo posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	Pity about the stripe slipping, looks good otherwise! With regards to the 3D core, I've recently discovered that they actually have a 'cosmetic side'. So if you look at it closely, there is a smooth side and a rough side. The smooth side should be placed towards the tool surface, and this reduces print-through. It still prints somewhat, but much better than when you place the rough side towards the mould surface! Also with the pinholes at the edges of the core, you can reduce this by butting up layers of fabric tape or strips of fabric to the edge of the core. The closer you build up the edges to the thickness of the core, the less bridging you will get and hence a better surface finish. I know the core isn't necessary on this piece, but just some tips in case you've got something you want to use it on later!
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Dravis	Dravis posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 592, Visits: 1.9K	@Hanaldo: Thanks for the advice on the 3D Core .. the edge problems probably goes for other core material as well, even though I not seen it with 2 mm Soric. This is the next one out of the mould .. narrower stripes this time, but perfectly aligned This time I made them by using Aerofix on the reverse of the stripe pieces, and "glued" them to a full sized piece of 200 gsm PW before laying up in the prepped mould .. then added one layer of 325 Satin W. a few cut offs as reinforcements, at top layer of 325 gsm Satin -- (I bought "discount roll" of that stuff from EC perfect for backing layers, drapes extremely well but needs a very light "mist" of aerofix to keep it from fraying up like mad at the edges when working with it) straigth out of the mould (Mould is no longer mirror polished, I had to buff it up again, but stopped at this dull finish, since I will need to clear coat anyway) Which I will try to do with XCR resin BTW .. and then polish --- "Sapere Aude"... Dare to KNOW! The written word is the only truly efficient vehicle for transmitting a complex concept from mind to mind... 103% of all people do not understand statistics... Do not adjust our mind, theres a fault in reality :-)
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*VVS*	*VVS* posted 9 Years Ago HOT Post Details
Group: Moderators Posts: 226, Visits: 334	Looks great, bad luck with the first attempt. first lay up in a new mould always offers up new ways of working easier second time around. nice tips with the core Hanaldo. will you post up a picture of the part when fitted. 👍
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meir	meir posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 8, Visits: 117	very interesting project. please keep us posted.
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davro	davro posted 9 Years Ago HOT Post Details
Group: Forum Members Posts: 300, Visits: 2.2K	Looking nice, and a lot better with the narrower stripes ! I need to get some Aerofix ... David Stevens YouTube: Comment \| Rate \| Subscribe Instagram Composite Projects Body Package for Dax Rush RC Car Touring Body 1/10 Scale
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