RCU Forums

RCU Forums (http://www.rcuniverse.com/forum/)
-   Tips & Techniques (http://www.rcuniverse.com/forum/tips-techniques-180/)
-   -   "Glazing Putty" for balsa? (http://www.rcuniverse.com/forum/tips-techniques-180/11244050-%22glazing-putty%22-balsa.html)

turbojoe 09-28-2012 12:04 PM

"Glazing Putty" for balsa?
 
I can't believe how bad this is frustrating me. Over the years I've tried a LOT of filler materials from spackling to micro balloons to some really crazy concoctions including auto body glazing putty. Nothing sands easy enough to feather out without damaging the surrounding balsa. Every filler I've tried is always too hard for my taste. I finally found a filler I'm really happy with. Elmer's Carpenter's wood filler "natural" color and it's awesome but still doesn't feather as easy as I'd like. I need something to use for that final sanding to smooth and feather. Any suggestions for an EASY sanding final feather option? Have I said "feather" enough? A nice random orbital sander in a size for R/C would be perfect but I haven't seen one of those yet....;)

Joe

91zulu 09-28-2012 12:22 PM

RE:
 
I use light weight spackle. Go to Home Depot and get the spackle tub that feels like there is nothing in it. That`s the one.

kenh3497 09-28-2012 12:50 PM

RE: RE:
 

Quote:

ORIGINAL: 91zulu

I use light weight spackle. Go to Home Depot and get the spackle tub that feels like there is nothing in it. That`s the one.

+100

i have even thinned it with water and slathered it all over a fuse to use as a leveler. Works great and weights nothing. Sands easier than balsa IMO.

turbojoe 09-28-2012 12:59 PM

RE: RE:
 
Thanks guys but I must have $30.00 worth of different spackle and I'm not happy with any of them. Even after thinning I don't get that smooth feather that I want. I just found a super old bottle of Pactra sanding sealer that will need some thinning to be useful. This is the direction I'm headed. A super smooth final surface. Not sure the sanding sealer is going to do it as the last time I tried it was on a mahogany boat. The mahogany was obviously harder than balsa. Gotta go to work now so will have to experiment some more this weekend.

Joe

jester_s1 09-28-2012 07:10 PM

RE:
 
The lightweight spackle will do what you're wanting, but don't put it on like you would normal wood putty. You can't press it in flat and make it stick. Slather the stuff on and let it dry, then sand it back off. It's really soft so it won't take long, and it will level out your finish.

Charlie P. 09-28-2012 07:50 PM

RE:
 
I use the Elmer's Carpenter filler.  Try watering it down for better feathering.

turbojoe 09-29-2012 12:12 AM

RE: RE:
 

Quote:

ORIGINAL: Charlie P.

I use the Elmer's Carpenter filler. Try watering it down for better feathering.
Thanks. I was planning to try that next. I do like how smooth it is compared to spackle. The color almost matches the balsa as well. If thinning helps it feather better then I'll be set. Planning to try WBPU and talc too. We'll see what works best.

Joe

turbojoe 09-29-2012 01:34 AM

RE: RE:
 
Ding, ding, ding, ding. We have a winner! The thinned Elmer's is exactly what I've been looking for. I thinned it to the consistency of cake frosting and spread it with a credit card. Got antsy so I hit it with the heat gun to speed the cure. Knocked it flat with some 400 grit and it feathered out beautifully. The coolest part is the color match. From a foot or so away you can barely see where I put it. From now on spackle only goes on walls. I wish I'd found this Elmer's filler many years ago! You gotta try this stuff guys. A tube at Walmart is under $3.00!

Joe

Toysareforkids 09-29-2012 03:18 AM

RE: RE:
 
I also have used a lot of different types of filler, and never really liked any of them.Ihave been using Elmer's on mycabinets and things like thatfora long time and then one day, I tried it on balsa, and have been using it since. Great stuff!

Pat

dbacque 09-29-2012 05:19 AM

RE:
 
Two things that affect the feathering ability of any filler are proper application and sanding technique. If the filler doesn't bond well with the surface it won't feather well. Also you mention your desire for a small orbital sander but this would be exactly the wrong thing to achieve a nice level, feathered surface.

Before applying the filler, make sure the surface is clean and dust free. Since you have been sanding there is lots of dust on the surface and you want the filler to adhere to the wood, not to the dust. A good vacuuming or a blow from a compressor hose will leave a nice solid surface for the filler to bond with, increasing it's feathering ability.

When sanding for a level surface it is important to use a long sanding bar and fresh sandpaper. Older paper will still feel rough to the touch but the cutting edges of the grit will have been dulled requiring greater pressure to make it cut. This additional pressure will cause uneven cutting of different surfaces as well as pushing down unsupported wood, creating a scalloped surface. And of course hand sanding with just paper (no block or bar) is absolutely out as you can't keep the surface level. The proper technique when you start to fill and final sand is to use a good, flat sanding bar with absolutely fresh sandpaper, I use 220 grit on an aluminum sanding bar. Use the lightest touch you can muster, let the sandpaper do all the work. Flow the sanding bar around the curves and use an orbital motion (there's your model sized orbital sander!) It's amazing how quickly that fresh paper will cut and how nicely a properly applied and sanded filler will feather.

Dave

foodstick 09-29-2012 07:40 AM

RE:
 
I will add this even though ts slightly off topic. If you use the light weight spackle and you are applying sig stixit to hold fabric.. be aware that if you try to reposition the fabric over the spackle the adhesive will often pull the spackle and destroy the smooth finish.. Be careful of that...

FMRR 09-30-2012 07:28 AM

RE:
 
Carl Goldberg makes a product called "Model Magic" product number #795 Strong,lightweight,non-shrinking and works with wood, foam and fiberglass.....feathers out great. Not sure if it's still available.

sebo 10-01-2012 12:18 AM

RE: RE:
 


I THINK THE FINER GRIT SANDPAPER IS THE SECRET TO FEATHERING.....THAT AND NOT TRYING TO HURRY THE JOB.
I USE THE LIGHT SPACKLING AND THE KIND THAT IS PINK AND DRIES WHITE WHEN READY TO SAND. BOTH HAVE THEIR PLACES.</p>

jaka 10-01-2012 08:32 AM

RE:
 
Hi!
Why do you use filler without first having covered the balsa with 25g glass weave /24 epoxy???
There is nothing as good as brown micro balloons and 24 hour epoxy when it comes to spacling.

raptureboy 10-01-2012 10:33 AM

RE: RE:
 
Sorry, I've been using it for 20+years as a carpenter. I buy it in the tub and if it gets a little hard just add some water and stir.Lightweight spackle has it's place and so does epoxy and micro balloons. All depends on what your trying to accomplish. But for making fillets around tail and stab joints it's great.

jaka 10-02-2012 07:44 AM

RE: RE:
 
Hi!
But it's so weak and brittle!

raptureboy 10-03-2012 06:42 AM

RE: RE:
 
No weakness at all. It's not the same as the lightweight balsa filler sold by hobbico and others. I've even used it outdoors as long as you paint over it later. It takes very little water to thin it so be careful. to each his own though, lots of ways to skin this cat.http://www.rcuniverse.com/forum/js/f...wink_smile.gif

LesUyeda 10-04-2012 06:30 AM

RE:
 
"Carl Goldberg makes a product called "Model Magic" product number #795 "

AKA Lightweight Vinyl Spackle:-)))))))))))) Available at Home Depot, Lowes, etc.

Les

OldScaleGuy 10-04-2012 08:28 AM

RE: RE:
 

Quote:

ORIGINAL: turbojoe

Ding, ding, ding, ding. We have a winner! The thinned Elmer's is exactly what I've been looking for. I thinned it to the consistency of cake frosting and spread it with a credit card. Got antsy so I hit it with the heat gun to speed the cure. Knocked it flat with some 400 grit and it feathered out beautifully. The coolest part is the color match. From a foot or so away you can barely see where I put it. From now on spackle only goes on walls. I wish I'd found this Elmer's filler many years ago! You gotta try this stuff guys. A tube at Walmart is under $3.00!

Joe
Bingo..... Been using it for several years myself. You will forget about the other items used for this job once you try Elmer's.


All times are GMT -8. The time now is 02:30 PM.