Polishing Doped Finishes

I just sprayed an final(?) clear coat of butyrate on my profile original and need to really cut the weight gain. All I can use here are my Preval canisters, and they do not atomize as well as normal spray outfits. So far, I've had the choice between brush marks and the fuzzy and/or orange peal textured surface. Each time I have wet sanded to a smooth surface, the next coat has left it porous appearing. However, weight says that I have more than enough clear on this thing. So I think I'll try polishing for some decent appearance.

I have done a search and read responses on polishing. The one thing that I am unclear on is residues and their affects. "Brasso" and "Blue Magic", among several have been recommended. Two uestions:

1) How do you use these - application cloths, amounts, etc.
2) What do you have to do in order to paint over or make repairs after using these products?

I'll be out of town until Monday, at which time I can decide whether it's time to polish. Thanks much for whatever advice any of you can supply during that time!

SK

Serge,

- I didn't know you were in the finishing stage, for I would have offered my spray equipment (just like we sprayed your P-Force);
- tape 4 of "Finishing with Brodak Dope" by Windy shows the step you're at (final wet sanding and buffing), you're welcome to borrow it (VHS);
- even if the polish leaves residue, I'd think that a fairly aggressive cleaner like M-600 should prep the surface for repairs, should you need any.

Serge, I think you are referring to things in the polish that might give problems if you have to repair the finish. Just be sure that whatever you use to polish that it does not contain any silicone in it. A lot of polishes do because it makes them easier to wipe off and it gives a long lasting shine. The problem is that it does not mix with paint over the top of it, and it is next to impossible to get cleaned off the old finish. It causes fisheyes and adheshion problems. Meguiars makes some that don't contain silicones. It will say so on the bottle. Hope this helps.
Joe Connelly

>I just sprayed an final(?) clear coat of butyrate on my
>profile original and need to really cut the weight gain. All I
>can use here are my Preval canisters, and they do not atomize
>as well as normal spray outfits. So far, I've had the choice
>between brush marks and the fuzzy and/or orange peal textured
>surface. Each time I have wet sanded to a smooth surface, the
>next coat has left it porous appearing. However, weight says
>that I have more than enough clear on this thing. So I think
>I'll try polishing for some decent appearance.
>
>I have done a search and read responses on polishing. The one
>thing that I am unclear on is residues and their affects.
>"Brasso" and "Blue Magic", among several
>have been recommended. Two uestions:
>
>1) How do you use these - application cloths, amounts, etc.
>2) What do you have to do in order to paint over or make
>repairs after using these products?
>
>I'll be out of town until Monday, at which time I can decide
>whether it's time to polish. Thanks much for whatever advice
>any of you can supply during that time!
>
>SK
>
>


Serge,

I am confused as to what stage of this in which you are using the "polish".

If it is essentially car wax, I don't feel it matters much as far as what one uses. I liked to wax 'er up with Johnson's yellow carnuba wax as it has no abrasives in which to scratch the soft dope.

If you are refering to polishes in which one uses to polish the dope finish to a sheen after sanding it with super fine sandpaper, I use silver polish, Gorhams is pink, Wright's is blue. I polish it until it is very shiny.

After sanding the whole ship with 600 or finer wet and dry, wet with water and dish soap, until it is all dull; use some soft cloth and begin to polish the surfaces to a shine again with the silver polish.
Any low spots (fish eyes, low spots in orange peel, etc) that remain dull are best sanded again.
If you are to the stage where you are saying "enough is enough", I would just clean out the residue with water and a little dish detergent and wax it up as well as you can.

You would want to protect the dope with wax as it helps keep out the oil and that is the main reason for all of the beautiful finish stuff anyway.

If you need to repair the finish I would clean the surface with Fantastic or Simple Green to remove all wax and then start your repair.

Chris...

Serge if you are trying to save weight you are going to have to sand the clear coat to remove it. That will be the only way to save weight. Polishing

Polishing comes after sanding and getting a smooth surface. Polishing wont remove weight, since it does not remove any of the clear coat. Lots of people step sand. They start with say 600, then 1000, then 1500, then you have to get the sanding marks out, use a compound fine or medium grit. Compound it until it shines. Then wax to protect finish and then polish for appearance points.

It is a long process. The better you are at spraying the less work between final coat and final polish.

Hi Serge:

My own experience with the preval units is that they work pretty well. I suspect that if you are getting a rough surface, you don't have the clear thinned enough and retarded to flow out.

Anyway, a system I like to use, especially on open bays is with the ultra-fine grit wet papers. I start with 600 (400 if really rought) then 1000, 1200, 2000. This will leave a nice satin surface and doesn't take very long.

If you want to go further, use the microfine cloth abrasives they use to polish plexi canopies and such. It goes all the way up to 12000 grit. I have left clear finishes alone after going to about 8000. It is finer than all but the gentlest pokishes.

If you really want to at the end, a little finesse from Meguires will finish it off.



FWIW

Curt

Curt

serge...on the clear butyrate...try an aicraft supply store at an airport in ur area...i havent done this in years myself but i have recently made a couple of calls...the manufacturer is RANDOLPH aircraft products in riverside cal...800-362-3490...they should be able to tell you who is closest in your area...or they may sell direct....they have colors too qts,gallons and 5 gallons...oh and its wayyyy cheaper bueno swerte'...jimmy ivey

>Hi Serge:
>
>My own experience with the preval units is that they work
>pretty well. I suspect that if you are getting a rough
>surface, you don't have the clear thinned enough and retarded
>to flow out.
>
>Anyway, a system I like to use, especially on open bays is
>with the ultra-fine grit wet papers. I start with 600 (400 if
>really rought) then 1000, 1200, 2000. This will leave a nice
>satin surface and doesn't take very long.
>
>If you want to go further, use the microfine cloth abrasives
>they use to polish plexi canopies and such. It goes all the
>way up to 12000 grit. I have left clear finishes alone after
>going to about 8000. It is finer than all but the gentlest
>pokishes.
>
>If you really want to at the end, a little finesse from
>Meguires will finish it off.

Just a minor clarification: the "Finesse-it II" is made by 3M, is a white kind of a semi-paste (it is dispensed by squeezing the material kinda like ketchup onto either the cloth or the surface to be polished), and is used by rubbing it on by hand with a damp terry cloth, buffing with it until the Finesse-it II is nearly dry. It is buffed off with a dry cloth, either terry or clean, bleached Tee shirt material.

"Finesse-it II" does a really nice job of putting a high gloss on the dope, after the dope has been sanded, as Curt said, up through 2000 grit wet.

Bill Byles


>
>
>
>FWIW
>
>Curt
>
>Curt

Absolutely---I use so many other Meguirs products in the squeeze bottle form, I forgot that the Finesse-it is a 3M product.

Thanks Bill.

Curt

Many thanks, Guys!

This was just the information I needed - sort of an orientation in final finishing.

For clarification, about weight saving, I just meant that the heaviness of the model prevented me from color coating and trimming over the Sig Super-Plyspan (dyed, older style silkspan). What I have is clear-doped wings, B-25 silver and clear coated fuselage (glassed) and stab, with a white "canopy". The Original plan of applying translucent color over the silver for a metallic color was just too heavy a finish. So I decided I needed to seal, smooth, and finally polish the clear...as-is.

The plane is just a profile; so I don't need a fine contest finish. But except for a couple too-much-trouble-to-fix spots, I want it to look as though I am not a complete Klutz. At least things smoothed up a bit as it set a few days while I was away. Thus the shininess thing.
Again, thanks for the thoughtful replies. I now have an idea of what does what in final finishing.

Edit: I FINALLY found my new digital picture file and discovered again how to get the pictures into my Picture Publisher Editor. Below SHOULD be some shots of the recent painting adventure, including #3, which shows how to make oneself refinish a stab: just splash thinner all over it. It's fixed now. #2 shows talc (from gloves) that I hadn't noticed to wipe off before snapping the picture, and #4 shows another reason I work so slowly.

Mike - Thanks for the offer. I think the little cannisters are all I can get away with in my basement though. I have no exhaust fan, nor a booth. This is a really amateur set-up here. At least there's a de-humidifier. Maybe I'll have something else this Spring though; so don't forget me!

SK


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Attachment #1, (jpg file)

'guess I used too much compression. Here's an original that should get in under 50K 5



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Attachment #1, (jpg file)

I sand up to 1500(sometimes 2000) grit using wet or dry sheets cut to 1/8 sheet size folded over and backed with a folded paper towel soaked in whatever wet lubricated medium of your choice. The folded paper backing allows for sanding softly along hard edges over open bay areas without cutting through as well as leveling out the surface.

Here is the final trick. After you have a smooth satin sheen without any pinhole highlights (as observed by candeling the surfact with a low angle light, I use a 18 inch florescent light); go to the medium rubbing compound then McGuires polishes (no wax yet) or Finesse it. But instead of using your hand and a polishing cloth use a 1/4 inch flexible shaft on a 1/4 HP high speed motor. A giant dremel if you will.

Go to Home Depot, buy two buffing wheel sets which include three cloth buffing wheels and a mandrel. Use one for the course grits and the other for the final polishes.

The trick is to use minimal compound, polish and artfully find the right speed and pressure to get that lusture shine. Remember in the service when you spit polished your boots and shoes. Same thing here. There is the right combination that pops that shine out. I think it has something to do with temperature, friction and the right combination of polish, pressure and cutting. Then protect it with McGuires Final Inspection. Again, no wax. Definitely do not use silicone. Carnuba wax can be cleaned off for paint prep but Silicone is nigh impossible to chemically remove unless you use MEK or other dangerous chemicals.



Here is the website
http://www.wecheer.com/content.php?view=product_show&cat=330

Here is the item

33030 20,000 100~120V 1/4 4.7 kg MOTOR, FLEXIBLE SHAFT, 26514 HANDPIECE,
VARI-SPEED FOOT CONTROL

Toss the vari-speed foot controller and get a dial controller. RPMs in the 400-700rpm range should work for Brodak and Randolphs dope.

Good luck

Bob Smiley

What Bob describes here is correct. The paint must get hot to melt it so to speak. The sanding knocks off the highs and the polishing fills the lows. 3M products are best for this process I have found. I mostly hand rub because I fear tearing the covering, it takes longer but just as affective. I do have a touch up 4 inch buffing pad,one for roughing and one for finishing that I can use on a high speed drill. Buffing should be done at no more that 1800 RPM.



>I sand up to 1500(sometimes 2000) grit using wet or dry
>sheets cut to 1/8 sheet size folded over and backed with a
>folded paper towel soaked in whatever wet lubricated medium of
>your choice. The folded paper backing allows for sanding
>softly along hard edges over open bay areas without cutting
>through as well as leveling out the surface.
>
>Here is the final trick. After you have a smooth satin sheen
>without any pinhole highlights (as observed by candeling the
>surfact with a low angle light, I use a 18 inch florescent
>light); go to the medium rubbing compound then McGuires
>polishes (no wax yet) or Finesse it. But instead of using your
>hand and a polishing cloth use a 1/4 inch flexible shaft on a
>1/4 HP high speed motor. A giant dremel if you will.
>
>Go to Home Depot, buy two buffing wheel sets which include
>three cloth buffing wheels and a mandrel. Use one for the
>course grits and the other for the final polishes.
>
>The trick is to use minimal compound, polish and artfully find
>the right speed and pressure to get that lusture shine.
>Remember in the service when you spit polished your boots and
>shoes. Same thing here. There is the right combination that
>pops that shine out. I think it has something to do with
>temperature, friction and the right combination of polish,
>pressure and cutting. Then protect it with McGuires Final
>Inspection. Again, no wax. Definitely do not use silicone.
>Carnuba wax can be cleaned off for paint prep but Silicone is
>nigh impossible to chemically remove unless you use MEK or
>other dangerous chemicals.
>
>
>
>Here is the website
>http://www.wecheer.com/content.php?view=product_show&cat=330
>
>Here is the item
>
>33030 20,000 100~120V 1/4 4.7 kg MOTOR, FLEXIBLE SHAFT, 26514
>HANDPIECE,
>VARI-SPEED FOOT CONTROL
>
>Toss the vari-speed foot controller and get a dial controller.
> RPMs in the 400-700rpm range should work for Brodak and
>Randolphs dope.
>
>Good luck
>
>Bob Smiley

Bob,

This is fantastic! How did you ever come up with an idea like this????

>I sand up to 1500(sometimes 2000) grit using wet or dry
>sheets cut to 1/8 sheet size folded over and backed with a
>folded paper towel soaked in whatever wet lubricated medium of
>your choice. The folded paper backing allows for sanding
>softly along hard edges over open bay areas without cutting
>through as well as leveling out the surface.
>
>Here is the final trick. After you have a smooth satin sheen
>without any pinhole highlights (as observed by candeling the
>surfact with a low angle light, I use a 18 inch florescent
>light); go to the medium rubbing compound then McGuires
>polishes (no wax yet) or Finesse it. But instead of using your
>hand and a polishing cloth use a 1/4 inch flexible shaft on a
>1/4 HP high speed motor. A giant dremel if you will.
>
>Go to Home Depot, buy two buffing wheel sets which include
>three cloth buffing wheels and a mandrel. Use one for the
>course grits and the other for the final polishes.
>
>The trick is to use minimal compound, polish and artfully find
>the right speed and pressure to get that lusture shine.
>Remember in the service when you spit polished your boots and
>shoes. Same thing here. There is the right combination that
>pops that shine out. I think it has something to do with
>temperature, friction and the right combination of polish,
>pressure and cutting. Then protect it with McGuires Final
>Inspection. Again, no wax. Definitely do not use silicone.
>Carnuba wax can be cleaned off for paint prep but Silicone is
>nigh impossible to chemically remove unless you use MEK or
>other dangerous chemicals.
>
>
>
>Here is the website
>http://www.wecheer.com/content.php?view=product_show&cat=330
>
>Here is the item
>
>33030 20,000 100~120V 1/4 4.7 kg MOTOR, FLEXIBLE SHAFT, 26514
>HANDPIECE,
>VARI-SPEED FOOT CONTROL
>
>Toss the vari-speed foot controller and get a dial controller.
> RPMs in the 400-700rpm range should work for Brodak and
>Randolphs dope.
>
>Good luck
>
>Bob Smiley

Bob,

This is fantastic! How did you ever come up with an idea like this????

PT Granderson