tacky bottoms

dannyP · Joined: 29 Sep 2009 Posts: 191 Location: tampa florida

I have had problems getting the bottom to dry all the way and I thought it was that I'm just impatient and I just have to take it out of the mold to see how it feels. Then searching here I found a thread that explained it was the type of resins reaction to curing exposed to open air so my question is has anyone tried cutting waxpaper or tinfoil to cover the bottom wen curing. I just wouldn't want to do it with something thatll not come off.
_________________
"Beauty is eternity looking at itself in a mirror. But YOU are eternity and YOU are the mirror."

holyreality · Joined: 28 Dec 2008 Posts: 18

goo dquestion, the smell left my hhg today but the bottom is sticky, maybe i could turn it upside down in the sun ?

NepiPemi · Posted: Fri Nov 27, 2009 4:46 am Post subject:

tacky bottoms
hmm, that is what you get for sitting under the pine trees.

sorry, couldn't resist

Yes, they will fully cure with a little heat.

Lesenthe · Joined: 07 Aug 2009 Posts: 123 Location: Australia

Most of my items wind up with tacky bottoms, too, and they persist in being tacky long after curing is complete. I solved the problem by thoroughly washing, and then sanding the bottom. After sanding, they're no longer tacky. I think it has something to do with the extremely glossy surface that fibreglass resin acquires when something is cured while exposed to air, but has no surfaces against it.

Let me know if this makes sense, and I'll post some pics if not.

Lena · Posted: Fri Nov 27, 2009 12:18 pm Post subject:

LOL, Nepipemi's comment made me laugh...

Sometimes the tackiness can also be residue from cutting oils from the metals used that came up to the surface and can be easily removed by giving them a wash. Try wiping it with a paper towel (of course you can also use toilet paper...) and you'll be able to tell if it's tacky resin or oily residue.

Lena
_________________
Change happens when we become aware of what we are already doing.

www.LenaRocks.com

dannyP · Joined: 29 Sep 2009 Posts: 191 Location: tampa florida

When you sand the bottom will it ever have that nice clear finish or does it have a scratchy look to it.
_________________
"Beauty is eternity looking at itself in a mirror. But YOU are eternity and YOU are the mirror."

Cosmic Sage · Posted: Fri Nov 27, 2009 1:35 pm Post subject:

I know I've had issues with sanding, even when wet sanding using 1000 grit paper, making the piece abit opague and not crystal clear like it was prior to sanding. I have experimented a bunch of ways with other sanding methods and still have no real set method that has worked for me. Any feedback is appreciated here as well.
_________________
Wisdom Begins In Wonder

Lesenthe · Joined: 07 Aug 2009 Posts: 123 Location: Australia

I'm glad I'm not alone in that. I thought I was just really bad or lazy with my sanding.

Thankfully, most of my stuff is black right now, and it kind of suits. Smile

jenjer · Joined: 08 Nov 2009 Posts: 3

I have had great success sanding my sticky bottom
First step, clean w/mineral spirit/acetone combo then simple green.than water
2nd sand w/80 grit, 30-60 seconds tops
3rd sand w/180 grit
4th 400 grit wet sand.( A little water and dish soap to lube )
5th wet sand w/1000 grit, as above
6th final polish w/ any white polishing compound Fitz, semichrome, brasso or the #5 sold at Lowes
The hole process takes less then 5 mins. and provides great clariyy and a great finished look

Blessings, Jerome.

Lesenthe · Joined: 07 Aug 2009 Posts: 123 Location: Australia

D'you have any pics of the finished product, jenjer?

Leo · Joined: 03 Nov 2009 Posts: 196 Location: Mid-Wales.UK

Interesting as this was a dilema for me with clearcast resin. which maybe slightly different. Here goes anyhow.
I found with clear resin that it needed to fully cure. I was filing the edges when it was still slightly tacky either at the top or on bottom of piece, but seemed cured. Which didn't work & was messy. Using a heater to put the curing pieces near too, as already mentioned here worked. Sometimes a couple of days, a few hours a day to make sure they are fully dried & settles before attempting to sand or file. This may be common sense. I assumed they were cured but needed longer to be workable for me.

I have had the cutting oil residue come up after curing(polyresin/field devices) separating & settling on top(rinse metal shavings?) which was weird at first, as Lena mentioned, though this wipes away easily. Often when the ratio of catatylst:resin is not quite right tackiness or uncuring also occured(mainly insufficient heat though). Not enough catalyst left it partially cured, so a drop of catalyst into each mould & mixing it in, if necessary sorted it. May be a factor in tackiness.
using a heater sorted out the problem for me. Also, obviously avoid touching the piece with fingers until it is fully cured if possible, or by the edges. Getting a nice clear finish seems to be practice in casting. Especially if it is a personal peice or non-field device.
My friend mentioned using a buffer to polish them up & bring a shine which I have yet to try. Sounds like there are some good ideas here.
lastly,
Silicone moulds instead of metal moulds incidentally, seemed to bring a nice natural shine to the finish of orgonite cast in them in my experience. It seemed to also be an indication of the energy of the orgonite. Ebay is great to finding cheap silicone moulds as is those cheapie shops & interestingly enough IKEA(not sure if that is international). THey are alot easier to pop out of the mould also! Laughing

Anyhow hope this helps.

Enjoy! Smile

Leo

dannyP · Joined: 29 Sep 2009 Posts: 191 Location: tampa florida

Thanks a lot for all the feedback every one ill just be more patient and then sand and buff if needed. I may try making a cap for the bottom to avoid air contact. Ill post about it onece its done.
_________________
"Beauty is eternity looking at itself in a mirror. But YOU are eternity and YOU are the mirror."

clipper · Posted: Sat Dec 19, 2009 7:28 am Post subject:

Before resorting to the whole sand/polish routine which turns out great for show pieces but is a lot of work, try the cleaning steps previously mentioned and then shoot the bottoms of the piece (or even the whole piece) with clear spray paint.

This was one of Sensei's tips some time ago. I've used this method and it works well and easily to seal up a tacky piece. Smile

Polish a show piece, spray the rest of them.

2 cents Smile

_________________
"I've let go the catch, we are over the edge, you have left me no where to go. Riding shotgun down the avalanche."
Shawn Colvin, Live'88