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kman-oz
16th April 2009, 02:46 PM
G'day all,

I'm trying to work out the best way to seal and fill various minor defects in some recycled Messmate, but I'm not sure if the usual sanding sealer is the best option. The final finish will be Shellac and I'm planning to use the same shellac as a sanding sealer, no issue there, but the larger defects are proving troublesome.

The timber is originally from a pier and has some visible weather checking and greying after jointing, which looks very nice I think. The problem is that the checking runs up to 3-4mm deep and perhaps 1mm wide at some points. I've tried four coats of Shellac based sealer, but I could be here all week filling them this way.

Might I try using one or two coat of sealer, filling the defects with epoxy or similar, then sanding and finishing with Shellac? I don't have any talc to make a thicker sealer, would this be a more suitable option? Perhaps there's another product that might do a better job? I'd like to make the filler clear rather than opaque if possible/practical.

Any other suggestions are welcome.

Dave.

chowcini
16th April 2009, 07:22 PM
yeah try using techni glue costs about $60 or $70 bucks for a litre dries clear and fills any hole or crack you need.
:2tsup:

toolbagsPLUS
16th April 2009, 09:13 PM
I make up a mix of Plaster of Paris with brick colour to colour match timber fill the offending area the when dry rub excess of with a nylon pad or very light rub with 150 paper and apply film of boiled linseed oil leave for a time till touch dry and shellac over the top of that.

Give it go it's cheap and works. Failing that get some colour wax sticks and melt into gaps the scrape of excess with a scraper and continue on.


Cheers


Steve

durwood
16th April 2009, 09:35 PM
Why not just use the product made for such jobs - wood filler?

"Timbermate" probabl;y your best bet.

Just follow the system-

Sealer for sealing _ (check previous threads)
Filler for filling
stain for staining
finishes for finishing

You will allway have problems if you try and make up your own system, more often it will not work as well as it can.

johnc
16th April 2009, 11:29 PM
Wax sticks, or bees wax and stain both work quite well. Timbermate has its place also, depends on preference.

kman-oz
17th April 2009, 01:02 PM
Thanks folks.

I don't want to use the timbermate or similar products if I can help it, I'd much rather a clear filler. I use timbermate for the unsightly blemishes like nail holes and such and it works very well, but the weather checking looks quite good. It very much gives the impression if both age and depth.

As a test I took a test peice and flooded it with Hard Burnishing Oil, then waxed and buffed it up. Looks awesome, but I still need to fill the cracks.

chowcini, I've just put some Techniglue in a test peice yesterday evening to try it out. I had some material with some very deep gum vein, maybe 10-15mm deep. If it works there it will work well anywhere! I'd only ever used it as a glue in the past and I have the impression is dried a little opaque. We'll see this evening. :)

johnc
17th April 2009, 01:41 PM
I use polyester resin when I don't want colour, its on the dark side of clear but seems to work well as a hole filler.

kman-oz
17th April 2009, 02:21 PM
I use polyester resin when I don't want colour, its on the dark side of clear but seems to work well as a hole filler.

That sounds promising, do you have a brand/product name? Polyester resin covers quite a bit of ground generically.

silentC
17th April 2009, 02:29 PM
I use norglass casting resin, which is a polyester resin. It dries water clear.

kman-oz
17th April 2009, 03:09 PM
That looks like exactly what I need, where to buy it?

silentC
17th April 2009, 03:18 PM
Well, I get mine at my local hardware, which is a Mitre 10. You'll find it wherever they keep fibreglass resins and the like. Don't forget to buy a bottle of catalyst, which doesn't usually come with it.

kman-oz
17th April 2009, 04:26 PM
Thank you very much sir! :)

JDarvall
17th April 2009, 04:49 PM
I'd lean towards a glue like epoxy (say) over filling it with wax. a wax won't stop the crack from continuing should it be so inclined. for colours I've just been using cement pigments of late. just powder. with a little stick just drop in a bit of it at a time while mixing until the colours good.

nine fingers
17th April 2009, 04:52 PM
Well, I get mine at my local hardware, which is a Mitre 10. You'll find it wherever they keep fibreglass resins and the like. Don't forget to buy a bottle of catalyst, which doesn't usually come with it.

I tried just about everything to fill flaws in myrtle burl vereer I use on jewellery boxes, last resort tried fibreglass resin ,mixed in redgum sander dust and then added the catalyst. Spread it over the problem area and sanded back, filled every nook and cranny, gave a beautiful finish.:2tsup:
cheers john

johnc
17th April 2009, 11:54 PM
It does fill well, and if you don't plug any holes underneath it also does a good job of filling every little nook and cranny on the work bench and floor.:2tsup:

scotty60
18th April 2009, 09:07 AM
seen some front doors done with old railway sleeper that were machined down to about 60mm thick and all the holes and cracks were filled with clear resin then stained and cleared ,these doors looked absoultly fantasic i was very impress but the price tag of $14000 bit to much for me

scotty :2tsup::2tsup:

kman-oz
18th April 2009, 11:43 PM
I've been out and purchased some casting resin this afternoon, coulnd't find Norglass, but my experience with Diggers products is good. I'll try that out tomorrow.

Um, Techniglue was a bit of a failure unfortunately. Maybe it's because I mix it to thoroughly but I managed to get a lot of air trapped in there and it's set a funny opaque blue colour. Not... really... what I was going for :)

As a test I tried filling a scrap peice with timbermate, then a light sand followed by sealer and French Polish and it also looks quite nice. After showing this sample to the customer he's asked if I can also stain it darker. Perhaps walnut.

So I have a new question: In what order? I'm thinking water based stain, then sanding sealer, then resin, then finish with Shellac. I'm limiting myself to water based stains only because I can be fairly certain that these won't interfere with any of the other steps. Does this sound ok?

Finishing is not something I have a lot of knowledge about, so feel free to fill me in if I'm missing anything. I do have a copy if Neil's handbook to brush up on also, but Neil discusses casting resin in passing only.

johnc
19th April 2009, 01:16 AM
I simply add the stain to the casting resin, seems to work ok. Generally its one of the Feast Watson stains, which has a lot to do with local availability. Generally though I dont use stain with resin leaving it clear.

silentC
20th April 2009, 09:39 AM
Regarding air bubbles, you can remove them by blowing over the surface with a hair dryer, or even just with your own breath.

I haven't had any experience with the diggers brand stuff. I've never seen it go blue, but I suppose if you have a lot of bubbles it might refract the light that way.

If you have a deep open void to fill, it's sometimes a good idea to wet the surface with a bit of the un-catalysed resin first - this helps prevent bubbles from forming on air trapped in there.

I've never tried it with stain, so not sure what would work best there. I usually fill the voids first, then scrape the excess resin away with a card scraper (must be very sharp). Sand the whole panel down to 400 grit, then apply sanding sealer, then sand to 800 then pad on shellac.

You have to be very careful when sanding or scraping the resin because it's harder than the surrounding wood and you can easily end up with valleys around the filler. Important to use a block if hand sanding.

kman-oz
20th April 2009, 02:55 PM
I simply add the stain to the casting resin, seems to work ok. Generally its one of the Feast Watson stains, which has a lot to do with local availability. Generally though I dont use stain with resin leaving it clear.

The Feast Watson stains I saw at Bunnies were alcohol based, and these work well with the casting resin? If so that's great, because I can make any stain colour I like with these.

silentC, the blue air bubbles I experienced were from the Techniglue, not the casting resin. I haven't tried the casting resin yet.

I think I'll have to experiment with the order to see what works best. I still think staining first is the best option, otherwise there might be some unseen resin still left in the pores which might interfere with the stain.

Incidentally, Neil's book recommends not using alcohol based stains under Shellac because they might be drawn out of the surface when the shellac is applied. I played with a few test peices over the weekend and found this to be something of a non-issue using the Feast Watson stains. I also tried making a tinted sanding sealer use the FW stain and shellac which worked very well. This is a lot of fun! :)

Thanks for your help folks.