Woodfinishinghelp.com Blog

Sanding Sealers (part one)

alanpoliver — Tue, 09 Jun 2009 22:45:47 +0000

Dewaxed Shellac acts as a very useful sealing coat. It’s particularly useful when sealing those surfaces that may be contaminated by silicone spray, from household aerosol cleaners and other contaminants. It is also good in those instances where the wood is oily as in teak and rosewood, and as in pine, which has knots that ’leak’ resin.

After applying the shellac, care must be taken when applying a coat of lacquer as too heaviy a coat may be too strong. This may result in the shellac liquefying. Apply light coat as a precaution. Once dry, coats can be then heavier.

Please note: Shellac must be the De waxed variety.

HVLP Spraying Help

alanpoliver — Thu, 04 Jun 2009 22:45:43 +0000

Question taken from http://woodworkingtalk.com

Hvlp spraying help ——————————————————————————–

I’m spraying an oil based primer. It seems like little speckles are coming out and creating an orange peel look. I thinned it with mineral spirits a little and added some penetrol. I have my air pressure set at around 8 psi. The paint seems to be leveling out alright but not perfectly smooth so I’m thinking there is something I can do to get it a little better. I’m thinking I should thin the primer a little more? Any help on spraying for beginners will be appreciated! Thanks

Here’s my tuppence!

A number of aspects need to be considered:
Temprature of spraying area, this will affect the flow (79 – 80 F).
Sieve the product using proprietry product or nylon stockings (ladies legs not in them at the time!).
The visco(u)sity – there will be an optimum flow rate for the product. Find out from your supplier/manufacturer and adjust accordingly. Use a viscousity cup. Product should travel a specified hieght in a specified time.
Check spray tip is appropriate diameter for product.
Make sure gun is thouroughly clean within.
If this all checks out increase pressure and build up using thinner coats and/or cut back with abrasives between coats.

Does lacquer go bad?

alanpoliver — Wed, 03 Jun 2009 22:45:47 +0000

Does lacquer go bad?

I have a few unopened quarts of Deft lacquer that have been sitting in my shop for the last 5 years. Any chance that this stuff is still usable?

Thoughts of Chairman Al:

It depends what type of lacquer. If we are talking about cellulose, pre cat or two pack lacquers I would advise differently.

As ‘neat’ cellulose is a ‘pure’ product I would say as long as the can is firmly sealed and kept in a cool place this should be o.k.
As pre cat is a mixture of catylizing agent and cellulose, I would say don’t use after year.
As a two pack, the lacquer and catalyzing are seperate. It will last longer, but, as to lasting five years, I wouldn’t use it!

Apologies

alanpoliver — Tue, 02 Jun 2009 22:45:42 +0000

Having moved home on April 28th, I’m still waiting for BT to provide me with an internet connection! So blogs have been, very recently, irregular. Sorry! Have been promised the 6th. Aaaargghh.

How to make lacquer less glossy?

alanpoliver — Wed, 20 May 2009 22:45:02 +0000

How to make lacquer less glossy? ——————————————————

question taken from http://woodworkingtalk.com–

———————— I just finished a table out of reclaimed pine.I sprayed it with Sherwin Williams lacquer.The can says medium rubbed effect on it.I was hoping for a little less shiny finish. Everything is hand planed which leaves it having a rippled effect.Is there anything I can spray over it that would take the gloss out? __________________

Here’s my tuppence:

There are a no of ways ;

use a fine grade 800 wet and dry paper with water.
use wire wool 0000 and wax
get the same make of finish and add a percentage of matt. to original can.

The first two you would rub with (along) grain. Last you would key finish and mix sheen levels.

Using Miniwax polyshades

alanpoliver — Tue, 19 May 2009 22:45:36 +0000

thinning miniwax polyshades

Question taken from http://woodworkingtalk.com

I am currently about to stain with a Miniwax polyshade. Is it possible to thin it. Its oil based and I know how to use thinner. But, not sure of how well it will work. I want it to stain very dark in the end, so I am needing several coats already but just curious if the thinner will affect the stain in the polyshade at all? Or if you have any other ideas on better application methods? I use a brush to put it on cause the cloth doesn’t seem to apply very well and then I let it stand for about 5 mins. then wipe down with a cloth and it was working but if it was thinner I think a cloth would be my choice of application.

Here’s my thoughts on the subject:

I agree with jerry, This product is a coloured lacquer. It is very difficult to control such finishes, (using brushes let alone cloth) unless you have spray equipment. With dark colours you could get streaking and you’d be going forever and a day back and forward trying to even the strokes/streaks out. Your best bet is to stain to the required colour, and then put a lacquer over.

Brush marks in shellac

alanpoliver — Mon, 18 May 2009 22:45:21 +0000

Brush marks in shellac

Hello there!
I’m finishing my wood floor in the living room. We applied our first coat of dewaxed shellac and it looks great. We are now lightly sanding this coat in preparation for another coat. Problem? We have a few places with brush marks (actually lap marks) and sanding is not really working….is there some sort of medium (i.e. denatured alcohol or mineral spirits) that would help the process? I know that alcohol is the solvent of shellac and I wouldn’t want to dissolve it away. But I’ve heard that technique used to repair old finishes. Then I read about using mineral spirits to sand but…? Help please

Here’s my reply. Try using a diluted shellac. Mix the meths with shellac. Half and half .

W/based finish over oil?

alanpoliver — Sun, 17 May 2009 22:45:27 +0000

Water based over oil based.

Hi everyone, nice site I just found. I just built a nice computer desk, and gave it the first coat of oil based poly, whao! the smell went from basement to 2nd floor house. Yes I had boiler off as well ass water heater and gas line turned off. I gave it a nice sand down with 320 and was wondering can I finish this off with waterbased poly instead?? I have 2 kids with asthma in the house and this oil base poly is a killer, takes too long to dry and its been humid lately too. Just asking for some opinions? Thanks to all..

Why didn’t you use a water based product from the start! You can keep the heat on and you don’t have to worry as much about the heavy vapours!

I wouldn’t put water on top of oil, as acryilic finishes are less flexible than the oil based finishes. Hope I’m not too late!

Teak repair

alanpoliver — Sat, 16 May 2009 22:45:24 +0000

Teak repair

I have a problem, I just finished my first large scale project with teak, I had a few areas which needed to be filled, due to defects in the stock. I now wish I just ordered more stock, and scrapped the pieces. I am trying to finish the teak, and the filler will not match(always light), and I didn’t really want to stain the wood, if you have a suggestion please help.

The above query taken from http://woodworkingtalk.com

You don’t mention the type of filler your using. You could use a two pack filler and colour it with pigmented powder. The powder will quite readily be taken and be a solid colour. Only add a little at a time, as the colour can be quite intense. Remember to key repair site so filler will grab the wood. Good Luck!

Restoring Garden Bench

alanpoliver — Fri, 15 May 2009 22:45:12 +0000

Your going to have a time consuming job restoring this garden bench. The bench hasn’t been properly maintained and the surface has become ’petrified’ . Good Luck.

This question is taken from www.woodworkingtalk.com. As I’ve never attempted such a job I leave the answer below. It makes sense what is said. I’m not sure what BLO is though! Any suggestions?

I bought this old, weathered, and very well used teak patio bench. My project or my idea is to rejuvenate the gray colored teak so it takes its original color but still look weathered or rustic. What should do? I am not a profesional woodworker (not even a rookie for that matter)

Thank you

Alfredo

Attached Images

Thank you

Alfredo

You can’t have it both ways. If you “clean” the Teak, the gray and black will likely be gone and you’re then back to the brown tones. The darkening of weathered Teak is from mold and mildew, and a depletion of oils in the wood.

There is no easy way to restore Teak to that brown state. Most brands of products have their own “cure”, which of course is their own products. Basically, the process is simple to understand, but somewhat labor intensive to accomplish.

The wood has to be cleaned which requires basically oxalic acid which depending on the product may require neutralization after the application. Using a fine bronze wool, and a stiff brush and or toothbrush for the corners, rub the surfaces to clean and at the same time the mold and mildew spores are killed.

Varnishes and any film finish traps the wood and will fail within a year depending on the exposure. Doing a re-finish to that will require a lot of sanding to remove the flakey crystallized finish. I prefer to use 100% pure Tung oil, thinned with naptha. BLO can also be used, but may add an ambering effect. This finish will also require maintenance as time evolves, but only for a good wipe down and a re-oil. Much less effort than film finishes.