How much additive F can one add to RR epoxy without seriously affecting its properties? The goal is to lower the viscosity. Greg…anyone?
Thanks in advance.
Meecrafty,
Upon recomendations from Greg, I’ve double the amount without any problems: Adding 2cc/2ml per ounce.
Are you looking to thin it even further?
Herb
i always use 1 cc per lam and 2 cc for the hot coat. for me i think that its just about the right consistancy.
i was told by fiberglass florida to make sure that the stuff is warm and shaken really well before you add it to your resin
I’m a lowly backyarder, but I found working with heat thinned the resin considerably…Keeping in mind the resultant shortening in working time and potential for runaway exotherm…I was mixing the resin warm (hot water) and pouring right away, which seemed to saturate the glass quickly (I was using lots of glass, 3x4 + 1x6). The stuff would be almost like water…very easy to mix/stir, and few bubbles…how about working in a warmer environment with a slower hardener? what’s your app.?
As for the F, mine partially solidifies below about 65. I always pop it into a bucket of hot water a few minutes before go time.
anyone have any temp. tips?
wells
Good stuff!
Yeah I’d like to experiment with very thin…around 500cps or less…I read somewhere that you can add up to about 12%/vol solvent to epoxy…any more and its properties change too much…but Im not an expert in this area.
5% denatured alcohol may be added. Heating is perfered though. Additive F is a surfacing agent and will reduce viscosty a bit but the denatured is better. Also if your using polystyrene foam, more than 3% Additive F may effect the foam. Denatured alcohol won’t. You can pour denatured on a polystyrene blank and it won’t do a thing to it. Not true with Add F.
I was curious what are you going to use the super thin epoxy for?
thanks greg good info…looks like another trip to HD…man I should own that place by now…dan, im experimenting…seems like there are multiple advantages to thinning the stuff…but i’ve hit a brick wall today…so its time to get out of the garage and just think for a while…its true…good things dont come easy…
Quote:
its true…good things dont come easy…
I couldn’t agree more!
How about for moulding fins and fin boxes?
If you had resin that was thin enough you could just pack a mould with reinforcement and pour the resin in.
I know with west system epoxy they say if you add too much thinner the epoxy will be weak.
I’m pretty sure I read somewhere that you can get epoxies that are thin like water. I haven’t looked into getting some yet.
http://www.fiberglasssupply.com/pdf/epoxy/Rot-Fix_tds.pdf
Actually here is one - System Three Rot-Fix. The above acrobat file does not list physical properties when cured but it says its solvent free. Viscosity is 300cps and hardener is 400 cps at room temp.
The intended application is for solidifying rotten wood but it might be worth trying.
For infusion (which is what your basically talking about) the general consensus among those involved in this technology is to use a higher viscosity resin and heat it to the desired viscosity with a very slow curing agent and then heat cure to your finished product. I’ve worked with a local company here in AZ that does exactly that in production of bow limbs and their method of heating works well to produce a very strong limb with fairly short cycle times.
Resins that have very low viscosity at room temps usually don’t have great physicals. In the case of a “Git-Rot” type product, your just looking to replace some rotting wood with a filler and that product works great. But in an application where your looking for strength, this wouldn’t be such a good product to use because it’s filled with viscosity reducers that reduce strength.
So the higher temperature infusion method is generally the accepted way to do this. We saw the writing on the wall for this particular application and developed the extra slow curing agent for this and some other uses (large hand lay-up stuff like boat hulls). A 200 minute pot life at 77º turns into a 50 minute pot life at 100º usually enough time to run an infusion part. Then baking your still molded part at 120º gives you a finished product in about 2-3 hours. We’ve had our stuff baked up over 150º and at that temp molds can be cycled even faster.