Confused about alumilite clear

[WHartman]

Finished a test pour last night and followed the direction sheet that came with my order. I also, before pouring searched the forums and followed some of the other suggestions and stirred until I thought it was clear, then mixed the two and stirred some more.

I then put it under pressure for 90 minutes at 60psi. When I pulled it out it was still soft and opaque!?! Is that right? I guess I was under the impression that it would cure clear, is this not the case? Its not a big deal if it doesn't, but I would like to be able to make a couple of clear blanks. If this does in fact not cure clear, is there anything on the market that will cure clear. The only reason why I ask is I am interested in making a demonstrator fp.

I appreciate the input. Thanks in advance.

Wade

 

[Russianwolf]

Yes it should cure clear.

BUT

Alumilite is very finicky about mixing. The ratio must be pretty accurate or it will come out opaque white. The ratio is harder to hit on small pours and gets progressively easier as the amounts increases (since its easier for most scales to measure larger weights).

I like some of the properties of Alumilite, but this is one big negative to me.

 

[theidlemind]

I use a very small digital scale to get my mixture right with Alumilite.
Also, silmar 41 is far better for clear casting usually.

 

[WHartman]

yup. I have small digital scale that I used also, thought I had it the equal. Its a 1:1 ratio correct? I was using it in oz's.

Thanks for the replies

 

[TomW]

How many ounces did you pour? I had problems initially with pours that were too small. There is something to the idea that bigger pours generate more heat and cure better. For example, single drops on the workbench stay sticky forever... Just a thought.

Tom

 

[Bocere1]

Finished a test pour last night and followed the direction sheet that came with my order. I also, before pouring searched the forums and followed some of the other suggestions and stirred until I thought it was clear, then mixed the two and stirred some more.

I then put it under pressure for 90 minutes at 60psi. When I pulled it out it was still soft and opaque!?! Is that right? I guess I was under the impression that it would cure clear, is this not the case? Its not a big deal if it doesn't, but I would like to be able to make a couple of clear blanks. If this does in fact not cure clear, is there anything on the market that will cure clear. The only reason why I ask is I am interested in making a demonstrator fp.

I appreciate the input. Thanks in advance.

Wade

When you say you stirred until you thought it was clear THEN mixed the two and stirred some more, what did you stir first and what was the two things you stirred together second?

It should be equal parts A and B by WEIGHT, mix till clear.

"Water Clear" and "Clear have different demold times.

If it was a small pour into a single pen mold of a couple of oz then you'll have to help it. Warm the molds then cure them in some low heat for a short time. I use an old Galloping Gourmet.

 

[commercialbuilder]

I just started casting with Alumilite clear and it has been extremely easy to me. I use digital postal scales and make sure I have part A and B measured as close as possible. I pour each in separate cups then mix together and stir for approximately two minutes and be sure I scrape the sides and bottom of the cup several times, It should be clear when finished mixing. If you are mixing two to three colors pour the mixed product into separate cups and add the coloring to each pour the colors into the mold and put in the pressure pot and let sit for thirty minutes. The one thing you may have missed is an ounce of parts a and b weigh I think 1.1 ounces each so if you need 10 ounces to fill the mold you would mix 5.5 ounces of each part to make 10 fluid ounces. If this does not work for you there may be something wrong with the Alumilite.

 

[PTownSubbie]

yup. I have small digital scale that I used also, thought I had it the equal. Its a 1:1 ratio correct? I was using it in oz's.

Thanks for the replies

Use it in the Gram mode vice Oz's. Too much variance possible between Oz measurements.......

You should measure to the exact gram vice ounce. Much much more accurate.

 

[WHartman]

Thanks for the suggestions guys. I'll give them a try tomorrow.

 

[redneckmedic]

Just because I haven't seen it mentioned yet....and its very important detail... there can NOT be any water in your cups, stir sticks, molds, noth'n! Alumilite is very sensitive to water, it will make the final product very cloudy.

 

[resinman]

Although it is recommended to mix by weight, you can also mix using graduated cups. I have made many blanks and knife scales just 1 at a time and had no problems.
The key is to mix for 1 minute after you put the "A" and "B" side together.
Remember, although, 7 minutes open time does not seem like much time, if you work steady in your mixing and pours, you won't even come close to 7 minutes.

 

[Russianwolf]

my scales go down to 5 gram increments. (.1 once on that scale) which on a small pour is still too much of a change in the ratio as they all came out white.


On the freaky side. The one time I wasn't trying to get clear (actually wanted the white) I just pour equal amounts into my mixing cup and BAMM, I get a clear cast. The stuff just doesn't like me I guess.

 

[WHartman]

Just wanted to let you guys know that I attempted another pour today for a clear blank and it worked great. I also tried some color blanks after pouring the one clear blank. What do you think?

Thanks for the great advice!

Wade

 

[Mike Powell]

I really like the green ones.

 

[Dick Mahany]

Just wanted to let you guys know that I attempted another pour today for a clear blank and it worked great. I also tried some color blanks after pouring the one clear blank. What do you think?

Thanks for the great advice!

Wade

Pretty nice, glad it finally cooperated with you. What did you use for casting tubes? I have read that Alumilite doesn't shrink and therefore PVC tubes aren't recommended unless one wants them to be disposable for each cast.

 

[WHartman]

For these, Im using a mold that I got from Fred (PTownSubbie), the 6 spot vertical round mold. No problems, great mold. I have used PVC with RC3 and it worked ok, had to bang out the blank, but otherwise it was fine.

 

[PTownSubbie]

For these, Im using a mold that I got from Fred (PTownSubbie), the 6 spot vertical round mold. No problems, great mold. I have used PVC with RC3 and it worked ok, had to bang out the blank, but otherwise it was fine.

If you use PVC and alumilite and you have to bang out your blanks, how many micro cracks do you think you create by doing that?

Much better your way Wade! Glad it is working for you!!

Much better cast. Must have been a measuring problem? Is that what you think?

 

[WHartman]

Yeah.. I think it probably had something to do with the amount or size of the pour. That first pour was only the one blank. The second clear pour was for 6. I just poured that before I mixed the colors.

As far as the micro cracks in the blanks, Ive turned several since then and they seem to be ok (knocking on wood ). Hopefully it wont be an issue, and now that I have ur mold, it wont be :biggrin:..


Wade