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Building Tips and technical articles. => Building techniques => Topic started by: James Mills on May 07, 2013, 10:46:22 PM
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Which glue do you guys use for gluing on the top and bottom blocks? I have aliphatic (Elmer's, Titebond), CA, SIGMENT, and epoxy.
James
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I use Elmer's on all the wood parts except the major joints like the wing, stab, motor mounts, and bellcrank.
Derek
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I use Elmer's on all the wood parts except the major joints like the wing, stab, motor mounts, and bellcrank.
Derek
Elmers woodworking glue, the yellow one?
What is the working time? Meaning if you are glueing in ribs and they need to stand up are you using pins to hold it all in place?
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Elmer's white glue just like the stuff you use to eat at school... LL~
It only takes a minute for the glue to grab, it is not dry but you cant move the pieces shorty after they touch. Dry enough to handle in an hour or so. Especially in the south where it is hot and probably even faster in west Texas where it is dry and hot.
You could use pins or sometimes I use a small dot of CA.
I use yellow wood glue some too, whenever I feel like I want to be extra safe and strong. Like gluing the wing in, before the epoxy gets added to the inside...
Derek
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Elmer's white glue just like the stuff you use to eat at school... LL~
;D ;D ;D It smells good, must taste good too... y1 y1 y1
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The kids on here probably never heard of the white paste we used to have before Elmer's came on the market. Its a wonder we are still alive. I can remember chewing cement off my fingers in high school.
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Use aliphatic/carpenters glue. I use a tip from Bob Hunt to wet the edge of the blocks or fuse sides with a Q-tip before glueing. The balsa swells up a little and this results in a "seamless" joint depending on your craftsmanship of course.
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I can remember chewing cement off my fingers in high school.
I can remember chewing cement off my fingers in the last six months -- how do you double-glue with Ambroid?
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I use CA. Must be the oddball here. Or anywhere, really.
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Always double glue with Ambroid or Sigment. Put a thin coat on, smear it around a bit let dry - even 5 minutes will do. Re-coat and put the pieces together. Usually pin or tape until dry. By the time you chew it off your fingers, it will be dry. Elmers glue - have tried it, found it doesn't sand well and gets gummy. Titebond - use the original, never Titebond II as it is difficult to sand. The original sands well but is often too thick and does not penetrate the fibers of the wood leaving a weak glue joint. Dilute it about 25% with water and it penetrates better. Wet both surfaces before applying, as was noted, they will swell up, the water base in Titebond helps here as well. If you have done it right the joint will be strong and virtually invisible. This is just what works for me. 8)
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Use aliphatic/carpenters glue. I use a tip from Bob Hunt to wet the edge of the blocks or fuse sides with a Q-tip before glueing. The balsa swells up a little and this results in a "seamless" joint depending on your craftsmanship of course.
I agree with Dennis, Use a Q Tip and wet the edge of the block, and the edge of the fuselage. It really does help to make a tighter seam. I did use Pica Gluit, but am looking to buy some guitar making glue, it is supposed to be the same.
BIG Bear
RNMM/AMM
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I understand every word of "put water on it so it will swell and make a better joint". And I understand "it will swell if you put water on it".
But why does making the wood swell make for a better joint? Does it insure contact all along the joint, even if there are little mismatches? Or do the joints to the formers (if any) get better when the wood dries and sucks up? Or what?
Inquiring minds want to know.
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It does not insure uniform contact but the light swelling will minimize any mismatched areas along the joint and make a tighter joint where they come together. This can be observed at any fuselage side / carved and hollowed block seam. And yes, if the glue is absobed somewhat by the wood it does make for a better joint in my humble opinion. I guess that is why I have found that thinned Tite-bond makes a better bond than straight Tite-bond which is pretty thick and at times does not sink into the grain but remains on the surface. 8)
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Like just another of too many cooks in the kitchen I'll give you my recipe. If what we do is about saving weight the glues are a major contributor to weight. I believe light to heavy are :
CA
Cement; Sigment, Bond 527, Ambroid
White or yellow glues
Gorilla glue
Epoxy
The strength factor is generally the same order assuming reasonable wood penetration. Of these I only use CA (Gorilla) , cement and epoxy. I choose according to how much strength that joint needs but lean toward the lightest choice. Generally epoxy is only used for hardwood or plywood. Cement is used where more work time is needed and some gap filling is needed while CA is best for well fitting lower stress joints that do not touch the outer surface where a finish is applied as is leaves a hard sharp edge that is hard to deal with when sanding the soft balsa as previously mentioned.
Given all I've said I glue top blocks on with cement except apply epoxy up front where is sits on the motor mounts and spacer block for fuel blockage. The block isn't a high stress part or joint. It needs to be light, easy to sand and maybe a little gap filling. For me that dictates the Bond 527 (Walmart) since the Sigment supply seems to have dried up.
I think double gluing is only required for cementing end grain joints. It's just more weight otherwise.
Dave
Addendum: I have been talking about the Bond 527 glue. It's been getting a little harder to find but usually Walmart and Michaels Crafts stores has it. I just read 'Bond 527' has been discontinued but the identical Beacon 527 -Beacon adhesives is the manufacturer- is the replacement. I'm going to their website tomorrow to see if I can get it direct and in bulk. You also might try that if you need cement.