Poscuring Nord RM3000 Tooling resin

General Composites Discussions Products Talk
#1

Hi guys

I would like to hear your opinion on the postcuring of RM3000.
I want to reach the maximum TG of 120 but my plug only holds up 60º. If I cure the huge mold at room temprature, afterwards demold and place the mold in a tent heated up to 120º should i expect deformation of the mold as it poscures without the plug to hold the shape? Placing propper supports seems fairly imposible due to the precision of the wingshape.
Would you otherwise recommend splitting the poscure into to cicles? Heating the mold to 60ºC then stopping, demolding and placing the mold into another tent where i can reach 120ºC? Interrupting the poscure is so critical?

#2

heat up as long as possible on the plug, cool down slowly, demould, and ramp up to heat again. No problem interrupting the process. What is important is your ramp, the Tg moves slightly ahead of your cure temp. If you overshoot your Tg the mould will become soft and deform. So, after demoulding really slow down your heating process. 10 degrees an hour maximum. If you have to stop you can ramp up faster to the maximum temperature you reached earlier, the slow down again.

#3

Thanks for the explanation. Very valuable

#4

If I remember correctly RM3000 isn’t suited for 120 degrees curing. Max 110 cure, but better is 100 degrees cure cycles. The TG will be 10 a 15 degrees higher.

#5

Thanks for the inputs. Nord recommends 3 layers of 100-300 g/m2 and then 8-12 layers of 450g/m2. I understand the 100-300 g/m2 shall be woven fabric. Is the 450 g/m2 woven or mat? Should i use 8 or 12 layers? I need a pretty huge amount of both fabrics. Anybody could show me where to source those fabrics at a competitive price?

#6

Have you ever worked with RM 3000 and why do you choose for RM 3000 ? What resin do you use for the first layers ? For the first layers don’t use 100 g/m2, a heavier fabric works better. I don’t use any woven fabrics for all the layers.

#7

I have chosen RM3000 because it has a TG high enough to allow prepreg as i want to try infusion and prepreg versions of the wing. And the price looks right. The manufacturer describes the 450 g/m2 as 40 tex (dont know what 40 tex means). ANy alternatives to Rm 3000?

#8

Tex is a unit of fibre measurment. I use only CSM with tooling systems. first layer a skin coat with a vinylester and 225 grams/m2 csm, then build up with tooling resin ands csm 450 g/m2(4 layers at a time), or even 600 g/m2(3 layers at a time).

I don’t know of other tooling systems with a Tg that high. I personally prefer neomould for non heated moulds.
Derakane is a vinylester wich can reach a high Tg.

Keep in mind that your mould can have a different expansion rate than your product. For a wing it shouldn’t be a problem, but some parts can get really stuck that way.

#9

Requires Neomould postcure? They seem to withstand 120º according to the brochure
BÜFA
®
-Tooling-System
In the GRP industry, only materials with the best product
properties are used for producing the highest quality
moulds. Extremely resistant to styrene and heat, high
mechanical loading capacity, a permanently good degree
of gloss as well as dimensional accuracy are the decisi-
ve criteria when it comes to selecting a reliable tooling
system.
Thanks to new developments in materials, our new
BÜFA
®
-VE-Tooling-Gelcoats fulfi
l these criteria. In
conjunction with the new low-styrene, fast curing and
practically shrink-free Neomould 1982-W-1, it is now
possible to produce moulds of the highest technical
quality with mirror-like surfaces in just one day instead
of a week.
Please fi
nd further product information (fi
ller, plasticines,
pastes, release agents, mould cleaner and wax) for
BÜFA
®
-Tooling-System in the brochure BÜFA
®
-Special
products.
BÜFA
®
-Tooling-System.
Demoulding on the second day.
Conventional Tooling System.
Demoulding on the fifth day.
BÜFA
®
-VE-Tooling-Gelcoat
Neomould 1982-W-1

#10

There are alternatives but most of them haven’t that high TG. RM 3000 and 120 is also a risk. I didn’t like the RM3000 that much an I now use optimold. Safes me money and works easier.

#11

Optimold shows a heat distortion temp of 100ºC. Does it need a postcure that high?