|
cheap vs expensive CA
I have been very fortunate as a Technical Sales Manager where I have sold some of the most expensive brands of CA, such as Loctite ( Henkel) and Wurth etc, and
believe me when I say that these are very good products and there is absolutely no doubt that they work well! I can quote all the sales buzz-words and reasons why the professional end user should shy away from the cheap stuff and only use the "brand stuff"!!! But now I find myself on the other side of the fence where I do not want to pay the heavy prices as I am the sole income earner in the family, and I have to save money where-ever I can. I love scratch building and I have found that the "cheap stuff" seemed to do the job just as well, and the small 20ml bottles stand up well to the high brands at literally a 10th of the price..... and I have yet to have a plane fall to pieces in the air while flying. Remember that aeroplanes are designed to fly and not to crash. Then I thought about how some of the modelers at my club scream about safety etc while they are "safely" flying their Oriental manufactured ARF with heaven only knows what adhesive was used LOL So....Is there an actual difference between the quality of the good stuff and the cheap stuff? Let me know what you think..... |
There is a difference for sure in the quality of adhesives. I am a composites tech by trade and like you I get to work with some really high end products and proprietary epoxy resin matrix systems. For my models I do not use any hobby type epoxy glues, I use a high quality epoxy laminating resin and add the appropriate fillers depending on the job at hand. As far as CA is concerned, I used to use nothing but Zap products as it was clearly better then other brands. I initially did not like the Bob Smith brands that many hobby shops now stock as their house brand. However after a few times of having to buy the Bob Smith CA when it was the only thing available I have noticed that it seems to have been improved and it now meets my needs. What does this mean tomthe average modeler? The answer is not a whole heck of a lot. Better adhesives means when building you can use less which will reduce cost and weight to a very small degree. Selecting the correct adhesive for the job IMO is much more important. A good example is sheeting a foam wing. I use laminating epoxy for this as well. I tape the sheets together, add a thin layer of epoxy and place the sheeting on the core, then the cores in the shucks and vacuum bag. When done the sheeting looks like it was one full sheet with no visible seams. Something that would be impossible if the sheeting was butt glued together with CA and bonded to the cores with contact cement. |
Originally Posted by speedracerntrixie
(Post 12488736)
There is a difference for sure in the quality of adhesives. I am a composites tech by trade and like you I get to work with some really high end products and proprietary epoxy resin matrix systems. For my models I do not use any hobby type epoxy glues, I use a high quality epoxy laminating resin and add the appropriate fillers depending on the job at hand. As far as CA is concerned, I used to use nothing but Zap products as it was clearly better then other brands. I initially did not like the Bob Smith brands that many hobby shops now stock as their house brand. However after a few times of having to buy the Bob Smith CA when it was the only thing available I have noticed that it seems to have been improved and it now meets my needs. What does this mean tomthe average modeler? The answer is not a whole heck of a lot. Better adhesives means when building you can use less which will reduce cost and weight to a very small degree. Selecting the correct adhesive for the job IMO is much more important. A good example is sheeting a foam wing. I use laminating epoxy for this as well. I tape the sheets together, add a thin layer of epoxy and place the sheeting on the core, then the cores in the shucks and vacuum bag. When done the sheeting looks like it was one full sheet with no visible seams. Something that would be impossible if the sheeting was butt glued together with CA and bonded to the cores with contact cement. There are some old school products that are exceptionally good for laminating foam cores, such as a water based latex glue which brushes on like thin milk and once it gets tacky it grips likes crazy, and in twenty years I have never seen this de-laminate. Another very good clean way of laminating foam cores is to used a watered down PVA (white wood glue) which is also brushed onto both surfaces and let to dry before positioning, then use a hot iron to iron the wood onto the foam.... the heat causes the PVA to polymerise and once again this is a permanent fix but with the added bonus of being able to reseat lifting laminate..... there are a few major advantages that both of these processes have over the two part resin compounds and they are: 1. Easy clean up with water... no acetone or keytone chemicals required 2. Low odour... can be worked inside the house. 3. quite flexible and not as brittle as polyester resin 4.not as sensitive to ambient curing temperatures. 4.no wastage as no mixing of activators, without the stress of curing deadlines. The only downfall is that these are no good for vac-bagging. Please keep in mind that I am a "low tech" balsa basher and have no idea how to use the high-tech compounds ...... . |
Another "low tech balsa basher" here. Good one, rinkhals01. Not wanting to pay more for the higher end CAs, there is a Hobby Lobby nearby that stocks thin, medium and thick off brand CA in various sizes. These have worked fine for me on several builds as long as you don`t use too sparingly.
|
Agreed, in 40 years of building I've never noticed enough of a difference to pay double for the so called "good" stuff,, The "works perfectly fine" stuff, works perfectly fine for me ;)
|
I stick to Carpenters Glue and epoxy of varying setting times and never the 5 minute types. CA simply doesn't do it for me.
Bottom line is most adhesives we use in the hobby, to include CA, if properly constructed the glue joint will be stronger than the surrounding material. Making the qualities of this or that glue a moot point. Now if you're one of those who uses the glue to fill the joint in an effort to make it better? That's a whole nuther issue which goes to your build skills vice the quality of the glue. I have a 38 year old Mini Antic by Proctor. Glued with some epoxy but mainly Elmers Carpenters Glue. Never a broken glue joint in all the years it's been flying. And as for flying, it is now on it's 3rd OS 35. |
There are actually times when you want a slight gap between parts, especially when using an epoxy based adhesive. In the aerospace industry it is referred to as maintaining the bond line. We use several methods to do this such as mixing glass beads into the epoxy, using shims or adjusting tooling that holds the parts during cure. Typically gaps range from .005 to .015. Remember when you glue two parts together you are actually gluing the parts to the glue and not to one another. |
Really,, ya have to have glue between the two parts? Who knew,, LOL
|
Originally Posted by scale only 4 me
(Post 12490339)
Really,, ya have to have glue between the two parts? Who knew,, LOL
Working with wood, the goal is for the glue to soak into the wood a bit. Making the last 1/16 inch or so of the wood pieces an integral part of the total glue joint. Foam would be similar depending on the specific type of foam. Something like glass or metal sheets, yes. A very thin layer of adhesive would be necessary. There is no single rule for everything. The materials and glue type all play into it. One of the things you learn in this hobby. But don't listen to someone with 61 years experience of sticking their fingers together. |
Originally Posted by scale only 4 me
(Post 12490339)
Really,, ya have to have glue between the two parts? Who knew,, LOL
|
| All times are GMT -8. The time now is 03:29 PM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.