Shellac, mixing.

[sb67]

I've been reading Gordon Gravetts book on scenic modelling and he uses mount board for road surfaces and concrete areas, after aying he then uses shellac, I've done a bit of research and I gather it's a type of polish and seems to come in flakes that you mix wih meths. I was wondering if there's any alternative or has anybody used it? I'm guessing it's a way of sealing the card before painting. 

Steve.

 

Edited September 5, 2018 by sb67

[Dava]

You can buy tinned Knotting from DIY shops, it's premixed shellac but costs more, eg from Wilko

[russ p]

Isn't it basically French polish?

If that's all it is the road would be very shiny

[sb67]

It gets painted when it's dry, I thought it might be a way of sealing the card prior to painting.

Steve.

[sb67]

You can buy tinned Knotting from DIY shops, it's premixed shellac but costs more, eg from Wilko

 

https://www.wilko.com/en-uk/colron-preparation-knotting-solution-125ml/p/0171277

 

Is that the stuff? It's not cheap, no pun intended ;-) 

Steve.

[Wellyboots]

Isn't it basically French polish?

If that's all it is the road would be very shiny

 

Yes the polishes are made from shellac, I'm not sure what is in the Knotting Solution but Colron also do a French Polish which they say is pure shellac.

Edited August 27, 2018 by Wellyboots

[smokebox]

The shellac is perhaps being used to harden the card rather than colour it.

 

For French polish I believe a higher quality version of methylated spirits is used to dissolve the shellac flakes , which has no dye in it

[PatB]

Shellac is used to both seal and harden the card. Well thinned it can penetrate the surface and, when dry, combines with the card to form a sort of fibre reinforced composite which can be very tough indeed. It's good for use on paper based products because it's not water based and so doesn't cause distortion to the same extent. Bought in flaked form it's not terribly expensive (I can get it here in Bunnings so I'd have thought the better UK DIY outlets would sell it at sensible prices), especially given that, for anything of modelling scale, you don't need that much.

 

I've also come across it as an ingredient in homebrew car underseal, but that's another story .

[dasatcopthorne]

I've been reading Gordon Gravetts book on scenic modelling and he uses mount board for road surfaces and concrete areas, after aying he then uses shellac, I've done a bit of research and I gather it's a type of polish and seems to come in flakes that you mix wih meths. I was wondering if there's any alternative or has anybody used it? I'm guessing it's a way of sealing the card before painting. 

Steve.

 

Steve.

 

I've used it extensively since 1971.

 

It can be considered as a paper and card sealer but never goes rock hard. Having said that, when used on card that is stable i.e. fixed to a hard surface, it is fine.

 

When used on card, probably at least two coats, it can be sanded with fine wet & dry to give a 'steel like' surface.

 

I mainly use is for coach sides which are then fixed to clear Perspex. I gives a near flush window.

 

The coach side is drawn on the card and the windows cut out. Shellac then applied one coat on the rear and two on the front. Front surface rubbed down and painted.

 

Here are a couple of pictures to show you.

 

I don't know where to buy flakes any more.

 

ps. Just looked on eBay. Button Polish is cheap on there and I've just seen flakes as well. (dissolve in meths, dead easy.).

 

Best of luck.

 

Dave Smith

[57xx]

 Bought in flaked form it's not terribly expensive (I can get it here in Bunnings so I'd have thought the better UK DIY outlets would sell it at sensible prices), especially given that, for anything of modelling scale, you don't need that much.

 

 

The flaw in your thinking is that our DIY sheds are actually any better than Bunnings...

 

That said, I did get 500ml of knotting solution from Toolstation for not very much £, though they don't seem to list it anymore.

 

https://flagpaints.co.uk/product-browser/2013/5/30/patent-knotting-solution

[JohnGi]

When used on card, probably at least two coats, it can be sanded with fine wet & dry to give a 'steel like' surface.

 

I mainly use is for coach sides which are then fixed to clear Perspex. I gives a near flush window.

 

The coach side is drawn on the card and the windows cut out. Shellac then applied one coat on the rear and two on the front. Front surface rubbed down and painted.

 

 

 

Walter Lishman wrote a couple of articles [scalefour news issues 126 and 127] on panelled coach construction in card. After the shellac dried, methylated spirit was used as a solvent glue to attach the panelling overlays to the sides. I haven't tried this myself but it looks like a slower and less aggressive technique than attaching plastic card layers using solvent glues - more time for adjustment and less chance of leaving fingerprints.

 

As the previous poster said you can sand the shellacked card. Mr Lishman also filed the window openings with a round file to form the corners - useful to be able to do this if you find accurately cutting on a curve problematic.

 

John

 

PS I have seen superglue mentioned as a alternative (to shellac) if you just need to harden card edges for filing.

Edited August 29, 2018 by JohnGi

[Nicktoix]

I've been reading Gordon Gravetts book on scenic modelling and he uses mount board for road surfaces and concrete areas, after aying he then uses shellac, I've done a bit of research and I gather it's a type of polish and seems to come in flakes that you mix wih meths. I was wondering if there's any alternative or has anybody used it? I'm guessing it's a way of sealing the card before painting. 

Steve.

Sanding sealer

Nick

[laurenceb]

The late Len Vass used wood hardener laterly

[decauville1126]

I seem to remember that back in the 1950's it could be home-brewed by breaking up old 78rpm records into tiny bits then dissolving in methylated spirits. Card modelling was quite popular back then, before George Slater brought styrene sheet to us as "Plastikard"

[sb67]

Thanks for all the replies guys, I've already got some MDF sealer, would that do the same job?

 

 

Steve.

 

I've used it extensively since 1971.

 

It can be considered as a paper and card sealer but never goes rock hard. Having said that, when used on card that is stable i.e. fixed to a hard surface, it is fine.

 

When used on card, probably at least two coats, it can be sanded with fine wet & dry to give a 'steel like' surface.

 

I mainly use is for coach sides which are then fixed to clear Perspex. I gives a near flush window.

 

The coach side is drawn on the card and the windows cut out. Shellac then applied one coat on the rear and two on the front. Front surface rubbed down and painted.

 

Here are a couple of pictures to show you.

 

I don't know where to buy flakes any more.

 

ps. Just looked on eBay. Button Polish is cheap on there and I've just seen flakes as well. (dissolve in meths, dead easy.).

 

Best of luck.

 

Dave Smith

 

 

That is some impressive work there Dave, best looking flush glazing I've seen. I'll look on e bay for the button polish later, thanks Dave.

Steve.

[justin1985]

I was recommended to get Button Polish as a ready to use Shellac based sealer for a similar purpose (sealing laser cut card parts before gluing/painting). I found the same Rustin's product in the photo above, now in a plastic bottle, in an old fashioned hardware store (never seen it in a DIY shed).

 

It seems to do a good job of making the surface of the card harder, and I've never noticed any swelling or softening of the card when using normal amounts of glue or arcylic paint once I've used it.

 

But it doesn't make it totally hard, or totally impervious to water. Just a bit stiffer and a bit less absorbent.

 

MDF sealer has a similar purpose, but is much runnier, and I think is not much different from dilute PVA. I'd certainly be vary of using it on card for risk of causing exactly the kind of damage you're trying to avoid. If it says brushes are water washable, then avoid. One of the main advantages of shellac related products seems to be that the solvent is meths, which evaporates so quickly it doesn't damage the card.

 

Justin

[Fat Controller]

As a slight distraction, here's the Wikipedia entry on shellac:-

https://en.wikipedia.org/wiki/Shellac

Fascinating stuff..

[sb67]

I was recommended to get Button Polish as a ready to use Shellac based sealer for a similar purpose (sealing laser cut card parts before gluing/painting). I found the same Rustin's product in the photo above, now in a plastic bottle, in an old fashioned hardware store (never seen it in a DIY shed).

 

It seems to do a good job of making the surface of the card harder, and I've never noticed any swelling or softening of the card when using normal amounts of glue or arcylic paint once I've used it.

 

But it doesn't make it totally hard, or totally impervious to water. Just a bit stiffer and a bit less absorbent.

 

MDF sealer has a similar purpose, but is much runnier, and I think is not much different from dilute PVA. I'd certainly be vary of using it on card for risk of causing exactly the kind of damage you're trying to avoid. If it says brushes are water washable, then avoid. One of the main advantages of shellac related products seems to be that the solvent is meths, which evaporates so quickly it doesn't damage the card.

 

Justin

 

Thanks Justin, the MDF sealer is water soluable and I did wonder about that.

Steve.

[dasatcopthorne]

Steve.

 

I've just revisited an Rmweb thread I wrote on building an EMU and it reminded me that if you buy flakes to dissolve, you must order 'de-waxed' flakes.

 

I came a cropper when trying to paint over the waxey type.

 

Dave.

[Pacific231G]

Can you use isopropyl alcohol rather than meths to dissolve shellac flakes? 

[Devo63]

I have been using shellac on and off since the 1970's for both card models and for sealing wood for sanding and finishing. I've successfully used it on the old style BSL wooden roofs to assist in preparation for painting and on thin balsa sheets used to construct coach and wagon bodies. I think I first used it after reading my father's ERG card models book when I was nine. I found that once a piece of card had been coated with shellac on both sides you could easily be sanded with very fine sandpapers. I would sometimes emboss plank lines and rivets on the cards when the shellac was dry then give them another coat before painting.

 

Dave R.   

[Dava]

Jim Read's work is a masterclass in shellacked card

 

http://www.rmweb.co.uk/community/index.php?/topic/124201-muckton-micro-terminus-conversion-4w-nsr-coach/page-3&do=findComment&comment=3256456

 

Dava

[Arun Sharma]

Shellac in solution can also be used to stick fag paper to the inside & outside of a metal chassis where there is any risk of a short circuit occurring - examples being say, around pony trucks and guard irons. Works a treat as an insulating device of almost zero thickness. It makes a brilliant liquid insulating paint.

[thaddeus]

Can you use isopropyl alcohol rather than meths to dissolve shellac flakes? 

yes, it works alright with very little difference. The alcohol flashes off at about the same rate as meths and importantly for French polishing ipa can be bought without the purple dye - not a problem with natural flakes but irritating when using blond granules for a clear finish.

Edited August 29, 2018 by thaddeus

[Il Grifone]

Back in the day, before plastic sneet, it was always recommended to seal the card with shellac to make it waterproof. As an added benefit, it hardens the card and helps to stop its annoying ability to form 'whiskers' when cut (use a Swann-Morten blade!).

 

That said my card wagons made without its assistance have all survived.

 

   Waffle alert!

 

78 r.p.m. records cab still be found in charity shops from time to time. They often have a premium price as assumed 'collectible'. Being played with steel needles with a playing weight measured in ounces will have ensured they aren't! (The needle and the abrasive shellac effectively destroyed each other on the first playing.) The same applies to vinyl and crystal 'rockbender' cartriges. Hence the universal provision of treble cut controls to remove the resulting distortion and crackle.

Edited August 30, 2018 by Il Grifone