Post by Mastercaster on May 3, 2011 12:25:27 GMT -8
resin tips:
1. Part "A" of any resin seems to be my enemy! It will crystallize and clog the tube of the wash bottle I pour out of.
2. Pour in part "A" of resin first. If you pour in part "B" first and have trouble with part "A" you will have a real mess.
3. Put a dab of silicone grease on bottle threads to keep them from being stuck shut. A real problem with part "A"! I use Dow Corning 111 silicone grease. You can go to ACE HARDWARE and buy a small container of plumber grease for cheaper. Silicone will not effect the resin.
4. Do what you can to keep from cross contaminating parts "A" and "B". Also, make certain that your work area is as level as possible.
5. If you decide to try clear resin do not pour out of bottles into smaller bottles that have flip caps. Here again, Part "A" is problematic. The bottle will not seal tightly enough and it will set up in the bottle.
cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310306387847&ssPageName=STRK:MEWAX:IT
I bought some of the link above. I have not tried them yet but hope it takes care of the problem.
6. I like to pour and store resins in smaller containers. They are easier for me to measure small amounts from at the time of use. I really like to use the laboratory washdown bottles with the removable straw in the middle for my regular resin use. Part "A" can and will clog the tube though on occasion. I use pipe cleaners and drill bits to clean it out. Using smaller containers are easier to hold and control pouring out of. Also make certain the inside lip of the bottle does not have a sharp edge on it's inside. This is a bit hard to describe. Remove the bottle top. Stick your small finger in the hole and spin the bottle. If it feels like there is a ridge there that could cut your finger remove it with an exacto knife. Resin will pour out more easily. Good bottles will not have this problem.
7. I bought a can of the blanket spray from SMOOTH ON that removes air from the top of the empty container to make the resin last longer. I believe it is nitrogen. I buy the gallon size resin kits. Please be aware that if you spray the blanket in the factory containers the bottles will actually suck down and make the bottle sort of implode. If you do this a number of times the bottle will crease and start to leak. I happen to look down one day and noticed a puddle. VERY BAD! This caused me to invest in heavy laboratory one gallon carboy NALGENE containers. These were about $40.00 each. Another expense added to my hobby.
www.dynalabcorp.com/wc1/productdetail.aspx?catalogid=1&categoryID=1&subcategoryid=1129&catcode=R&subcatcode=26&subcatdesc=Carboys++++++++++++++++++&subcat2code=R&subcat2desc=Round+Carboys++++++++++++&subcat3code=N&subcat3desc=Round+Carboys+No+Spigot++&itemnumber=870-0000%20%20%20%20%20%20%20&price=42.9700
The above link is an example of a one gallon bottle I am using for a reasonable price.
8. cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220774900000&ssPageName=STRK:MEWAX:IT
Get a scale like the one in the above link. Do not waste your time with a cheap electronic scale. This one is a pretty good deal. I sure wish I would have chosen this style instead of the other one I bought. This one will weigh more than the one I bought. You can also put boxes on it for an idea of a mailing weight. You will also want to turn your ceiling fan off when you have a cup on your scale.
faculty.brownell.edu/~jomayo/dialogram.html
Do not buy the style in the above link. This is the one I bought and I chose poorly and did not think it through! You will not be able to put a very big container on it. You will be limited by the cup height and diameter with all the mechanism above it. I am only able to do 100 grams of silicone at a time. Once you measure the silicone and mix it and then put it in a vacuum chamber it will nearly go to the top of the cup when vacuuming the bubbles out.
9. I would suggest that you vacuum or pressurize the poured silicone to get rid of bubbles as best you can. Do small pours if need be and look for captured air against parts, this might be hard to do too. Silicone can start curing before all the bubbles have escaped. If they are near the surface of your part the part might be hard to work with or will be junk. Even with all my efforts, problems and imperfections can still happen. I picked up a mold one day that had been made for a good while. The top part had a funny looking bulge on it. I really wish I would of had the smarts to take a picture of it. I stuck it with an exacto knife and darned if it was not an air bubble.
10. Make parts from two part molds. One of the model magazines published an article about the best parts are cast from good two part molds.
11. when pouring silicone into side two of your mold. Make certain there is enough silicone to reach the top edge. I like to overfill them. This adds needed weight to help make a good part. And a good solid surface for my secret weapon
12. BE PATIENT! Once you have poured the well stirred resin in the mold, put the two halves together and put in a pressure pot. Do not take out and open for at least 30 minutes. It is better to go and focus on something else for awhile. Pulling a not fully cured soft part out of a mold will usually deform the part permanently.
13. Be sure to stir the resin parts one to one only and stir very well. Sometimes the TASK 8 resin I use does not seem to want to mix at all making a part that looks swirled in colors or still liquid in an area.
14. If there is an area in the mold where resin did not fully cure use a plastic shopping bag to push firmly into the area with. The sticky resin should stick to the plastic bag and pull away from the mold without any problems. This will be important for molds that make clear windshields, etc. A Q-tip with a good coat of mold release will work too.
15. Molds that are intended for making clear windshields, etc should have regular resin poured in and fully cured a couple of times to remove any mold release. This is a personal presumption from experience.
There is actually very little mold release in contact with the part from the first few pulls.
16. After pouring mixed resin in the mold and it is in a pressure pot, do not forget to get right on cleaning out any resin that is left in the cup. I clean them out with TP and alcohol I get from the Home Depot paint department. I buy it by the gallon. I do not like the little cups that come from cough medicine as they do not have pour spouts. Some of them have little ridges in the bottom that stir sticks catch on while stirring briskly causing little drops of resin to fling out. Also be careful to hold the cup away from your face so none of it gets in your eyes or on your glasses lens
17. After the first 6 or so pulls you should spray the surface with a mold release. Let it set for about 30 minutes and take a small paint brush and brush it good, this will smooth out and remove excess mold release making a nice smooth part. This will be hard to do with small parts but important on bodies and hoods. Do not spray mold release in a mold and then pour resin in right away. The resin will never fully cure making a rubbery feeling part.
18. I like to polish bodies , hoods, etc. until they are shiny. I figure the smoother the part the easier it will be to demold the part and the more uses you will get from a mold. This is important for windshields.
19. Especially for body molds. Store body molds with resin in them. I have learned to do this. Do not stack empty body molds on one another. They will make deformed bodies and are junk.
20. Keep all scraps of silicone. It can be chopped up and used for filler in a new mold. It will be important to take the thin layers and add them to silicone and let them cure and then cut it up and then grind it. Adding thin layers or peelings from cups into fresh silicone might be a problem. Air could become trapped in it next to some detail making the mold useless. This seems like a sacrificial waste but all silicone can be reused.
21. Wipe all used molds down with alcohol or purple cleaner before cutting and grinding just to be safe to remove mold release.
22. Because you took the time to make a mold with several small parts , it might be better to mix a smaller amount of resin at one time and pour only a small number of cells to get better results. The resin I use can kick pretty fast!
23. Learn not to put too much resin in a cell. Sometimes it will be necessary to pour some resin on both parts of the mold so as not to trap air and create a part that is not fully formed. You can take an exacto knife and cut the mold so that cells with small parts can be opened and resin can be poured in. It can be very frustrating and difficult work. Parts that constantly come out deformed are a waste of time and resin. I don't think you can grind up and reuse resin!
24. I recently made a body mold from a very nice 1954 Buick Skylark convertible. After looking carefully at the first two bodies I made, I noticed that the tiny hood ornament was not completely made as a tiny bubble of air was trapped both times in the mold. I took a flat toothpick and after pouring the resin in and swishing it around to cover the inside of the mold I drug the tip through that part to remove the air.
25. If you just starting to learn resin cast work I strongly urge you to do dry runs of going through the action of mixing pouring resin in a mold and going through the motion of taking TP and wiping out your pouring container if you decide to use a high quality beaker like I do. You want to instill a consistent way of making parts as I have done. Then you can move up to using alcohol in place of resin as a next step up of getting used to doing resin casting. (the kind of alcohol I use to clean up with!) You may laugh and make fun of me but it will create a more consistent way to making great parts. You need to instill in your mind that getting the excess resin out of your expensive beakers is very important. Trying to remove cured resin from a beaker is very hard to do.
26. You may be wise to create a casting log. subjects could include:
Date the mold was made.
Keeping track of the number of parts pulled from the mold.
And at this writing I wish I had kept track of how much resin it took to make the part the mold is to produce. If you have not used a mold for awhile this will become valuable information if you can't remember anything anyway!
How much silicone it took to make the mold.
Brand and type of silicone.
27. Make certain that the two mold parts fit together nicely without be forced together on small molds. Having to force the two parts together after you have poured resin in may cause some excess resin to squirt out. And it could do this in your face or some young person that can't wait to help Mom or Dad with making parts. Also be careful of pets and long wagging tails.
28.
I just started a new gallon kit of TASK 8 by SMOOTH ON. The above picture is of the bottle of part "B" cut open. I should have taken a pic when I first cut it open. In the lower right corner is a sample of a settled white portion of this part of the resin. It was much worse. I scraped out what I could and put it in a container of the liquid part and mixed it until it became a liquid again. Using stainless steel bolts or nuts as mixing aids would be a good idea. Part "A" does not seem to settle out but will crystallize easily.
29. If you convert a pressure pot out of a stove top pressure cooker you should put an elbow or bent piece of pie in the underside of the lid so that air will not blow straight down into a open one piece mold full of resin. The blast of air will cause a big splash.
30. SILICONE MATERIALS= There are different types of silicones. Some mix 1:1. Some have a separate activator that mixes 10 parts activator to 100 parts of silicone. Some companies might tell you that you do not need to vacuum the silicone. Here is a point you will need to keep in mind. You may very well be successful with a mold if your mold is not very thick. It might work very well if it is only one inch deep or less. Body molds are deep. about four inches or so. You can do several small pours say 110 grams at a time. The problem is that some silicones may not let the separate pours or layers bond if they come to a full cure meaning that layers may quickly or eventually delaminate. You may want to test your silicone for this.
1. Part "A" of any resin seems to be my enemy! It will crystallize and clog the tube of the wash bottle I pour out of.
2. Pour in part "A" of resin first. If you pour in part "B" first and have trouble with part "A" you will have a real mess.
3. Put a dab of silicone grease on bottle threads to keep them from being stuck shut. A real problem with part "A"! I use Dow Corning 111 silicone grease. You can go to ACE HARDWARE and buy a small container of plumber grease for cheaper. Silicone will not effect the resin.
4. Do what you can to keep from cross contaminating parts "A" and "B". Also, make certain that your work area is as level as possible.
5. If you decide to try clear resin do not pour out of bottles into smaller bottles that have flip caps. Here again, Part "A" is problematic. The bottle will not seal tightly enough and it will set up in the bottle.
cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310306387847&ssPageName=STRK:MEWAX:IT
I bought some of the link above. I have not tried them yet but hope it takes care of the problem.
6. I like to pour and store resins in smaller containers. They are easier for me to measure small amounts from at the time of use. I really like to use the laboratory washdown bottles with the removable straw in the middle for my regular resin use. Part "A" can and will clog the tube though on occasion. I use pipe cleaners and drill bits to clean it out. Using smaller containers are easier to hold and control pouring out of. Also make certain the inside lip of the bottle does not have a sharp edge on it's inside. This is a bit hard to describe. Remove the bottle top. Stick your small finger in the hole and spin the bottle. If it feels like there is a ridge there that could cut your finger remove it with an exacto knife. Resin will pour out more easily. Good bottles will not have this problem.
7. I bought a can of the blanket spray from SMOOTH ON that removes air from the top of the empty container to make the resin last longer. I believe it is nitrogen. I buy the gallon size resin kits. Please be aware that if you spray the blanket in the factory containers the bottles will actually suck down and make the bottle sort of implode. If you do this a number of times the bottle will crease and start to leak. I happen to look down one day and noticed a puddle. VERY BAD! This caused me to invest in heavy laboratory one gallon carboy NALGENE containers. These were about $40.00 each. Another expense added to my hobby.
www.dynalabcorp.com/wc1/productdetail.aspx?catalogid=1&categoryID=1&subcategoryid=1129&catcode=R&subcatcode=26&subcatdesc=Carboys++++++++++++++++++&subcat2code=R&subcat2desc=Round+Carboys++++++++++++&subcat3code=N&subcat3desc=Round+Carboys+No+Spigot++&itemnumber=870-0000%20%20%20%20%20%20%20&price=42.9700
The above link is an example of a one gallon bottle I am using for a reasonable price.
8. cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220774900000&ssPageName=STRK:MEWAX:IT
Get a scale like the one in the above link. Do not waste your time with a cheap electronic scale. This one is a pretty good deal. I sure wish I would have chosen this style instead of the other one I bought. This one will weigh more than the one I bought. You can also put boxes on it for an idea of a mailing weight. You will also want to turn your ceiling fan off when you have a cup on your scale.
faculty.brownell.edu/~jomayo/dialogram.html
Do not buy the style in the above link. This is the one I bought and I chose poorly and did not think it through! You will not be able to put a very big container on it. You will be limited by the cup height and diameter with all the mechanism above it. I am only able to do 100 grams of silicone at a time. Once you measure the silicone and mix it and then put it in a vacuum chamber it will nearly go to the top of the cup when vacuuming the bubbles out.
9. I would suggest that you vacuum or pressurize the poured silicone to get rid of bubbles as best you can. Do small pours if need be and look for captured air against parts, this might be hard to do too. Silicone can start curing before all the bubbles have escaped. If they are near the surface of your part the part might be hard to work with or will be junk. Even with all my efforts, problems and imperfections can still happen. I picked up a mold one day that had been made for a good while. The top part had a funny looking bulge on it. I really wish I would of had the smarts to take a picture of it. I stuck it with an exacto knife and darned if it was not an air bubble.
10. Make parts from two part molds. One of the model magazines published an article about the best parts are cast from good two part molds.
11. when pouring silicone into side two of your mold. Make certain there is enough silicone to reach the top edge. I like to overfill them. This adds needed weight to help make a good part. And a good solid surface for my secret weapon
12. BE PATIENT! Once you have poured the well stirred resin in the mold, put the two halves together and put in a pressure pot. Do not take out and open for at least 30 minutes. It is better to go and focus on something else for awhile. Pulling a not fully cured soft part out of a mold will usually deform the part permanently.
13. Be sure to stir the resin parts one to one only and stir very well. Sometimes the TASK 8 resin I use does not seem to want to mix at all making a part that looks swirled in colors or still liquid in an area.
14. If there is an area in the mold where resin did not fully cure use a plastic shopping bag to push firmly into the area with. The sticky resin should stick to the plastic bag and pull away from the mold without any problems. This will be important for molds that make clear windshields, etc. A Q-tip with a good coat of mold release will work too.
15. Molds that are intended for making clear windshields, etc should have regular resin poured in and fully cured a couple of times to remove any mold release. This is a personal presumption from experience.
There is actually very little mold release in contact with the part from the first few pulls.
16. After pouring mixed resin in the mold and it is in a pressure pot, do not forget to get right on cleaning out any resin that is left in the cup. I clean them out with TP and alcohol I get from the Home Depot paint department. I buy it by the gallon. I do not like the little cups that come from cough medicine as they do not have pour spouts. Some of them have little ridges in the bottom that stir sticks catch on while stirring briskly causing little drops of resin to fling out. Also be careful to hold the cup away from your face so none of it gets in your eyes or on your glasses lens
17. After the first 6 or so pulls you should spray the surface with a mold release. Let it set for about 30 minutes and take a small paint brush and brush it good, this will smooth out and remove excess mold release making a nice smooth part. This will be hard to do with small parts but important on bodies and hoods. Do not spray mold release in a mold and then pour resin in right away. The resin will never fully cure making a rubbery feeling part.
18. I like to polish bodies , hoods, etc. until they are shiny. I figure the smoother the part the easier it will be to demold the part and the more uses you will get from a mold. This is important for windshields.
19. Especially for body molds. Store body molds with resin in them. I have learned to do this. Do not stack empty body molds on one another. They will make deformed bodies and are junk.
20. Keep all scraps of silicone. It can be chopped up and used for filler in a new mold. It will be important to take the thin layers and add them to silicone and let them cure and then cut it up and then grind it. Adding thin layers or peelings from cups into fresh silicone might be a problem. Air could become trapped in it next to some detail making the mold useless. This seems like a sacrificial waste but all silicone can be reused.
21. Wipe all used molds down with alcohol or purple cleaner before cutting and grinding just to be safe to remove mold release.
22. Because you took the time to make a mold with several small parts , it might be better to mix a smaller amount of resin at one time and pour only a small number of cells to get better results. The resin I use can kick pretty fast!
23. Learn not to put too much resin in a cell. Sometimes it will be necessary to pour some resin on both parts of the mold so as not to trap air and create a part that is not fully formed. You can take an exacto knife and cut the mold so that cells with small parts can be opened and resin can be poured in. It can be very frustrating and difficult work. Parts that constantly come out deformed are a waste of time and resin. I don't think you can grind up and reuse resin!
24. I recently made a body mold from a very nice 1954 Buick Skylark convertible. After looking carefully at the first two bodies I made, I noticed that the tiny hood ornament was not completely made as a tiny bubble of air was trapped both times in the mold. I took a flat toothpick and after pouring the resin in and swishing it around to cover the inside of the mold I drug the tip through that part to remove the air.
25. If you just starting to learn resin cast work I strongly urge you to do dry runs of going through the action of mixing pouring resin in a mold and going through the motion of taking TP and wiping out your pouring container if you decide to use a high quality beaker like I do. You want to instill a consistent way of making parts as I have done. Then you can move up to using alcohol in place of resin as a next step up of getting used to doing resin casting. (the kind of alcohol I use to clean up with!) You may laugh and make fun of me but it will create a more consistent way to making great parts. You need to instill in your mind that getting the excess resin out of your expensive beakers is very important. Trying to remove cured resin from a beaker is very hard to do.
26. You may be wise to create a casting log. subjects could include:
Date the mold was made.
Keeping track of the number of parts pulled from the mold.
And at this writing I wish I had kept track of how much resin it took to make the part the mold is to produce. If you have not used a mold for awhile this will become valuable information if you can't remember anything anyway!
How much silicone it took to make the mold.
Brand and type of silicone.
27. Make certain that the two mold parts fit together nicely without be forced together on small molds. Having to force the two parts together after you have poured resin in may cause some excess resin to squirt out. And it could do this in your face or some young person that can't wait to help Mom or Dad with making parts. Also be careful of pets and long wagging tails.
28.
I just started a new gallon kit of TASK 8 by SMOOTH ON. The above picture is of the bottle of part "B" cut open. I should have taken a pic when I first cut it open. In the lower right corner is a sample of a settled white portion of this part of the resin. It was much worse. I scraped out what I could and put it in a container of the liquid part and mixed it until it became a liquid again. Using stainless steel bolts or nuts as mixing aids would be a good idea. Part "A" does not seem to settle out but will crystallize easily.
29. If you convert a pressure pot out of a stove top pressure cooker you should put an elbow or bent piece of pie in the underside of the lid so that air will not blow straight down into a open one piece mold full of resin. The blast of air will cause a big splash.
30. SILICONE MATERIALS= There are different types of silicones. Some mix 1:1. Some have a separate activator that mixes 10 parts activator to 100 parts of silicone. Some companies might tell you that you do not need to vacuum the silicone. Here is a point you will need to keep in mind. You may very well be successful with a mold if your mold is not very thick. It might work very well if it is only one inch deep or less. Body molds are deep. about four inches or so. You can do several small pours say 110 grams at a time. The problem is that some silicones may not let the separate pours or layers bond if they come to a full cure meaning that layers may quickly or eventually delaminate. You may want to test your silicone for this.
