PDA

View Full Version : Anyone else making their own food safe finish?



Dean0
15th September 2015, 01:08 AM
I gave been making this one for a while. I haven't thinned it for hard wood and use it on the lathe. Only problem I am finding the piece is stuck there for 24 hrs between coats.

Recipe goes:
250ml linseed oil (not boiled)
40-50gms bees wax
10-15gms canubar wax
put in a double boiler till dissolved.
Cool and use. I am finding this brings out fiddleback better then Tung. It also holds a reasonable lustre when polished with paper.

Drawbacks: you have to make it and stir a lot.
Carbnura is not always available.
Lit takes a longer time to dry but fives you the figure accents linseed is known for.

Id love to hear from others that use/make similar.

Cheers

dr4g0nfly
15th September 2015, 05:25 AM
I can't speak for you in Aus, but here in the UK 'Food Safe' is a legal definition. There are many oils and finishes which we can make or buy to use, which are not deleterious but to get the 'Food Safe' label, they have to go through a rigorous testing and proving regime.

But I like the recipe, consider it stolen.

Paul39
15th September 2015, 12:41 PM
DeanO,

I use tung oil almost exclusively. I have used raw linseed oil and wipe on poly, but keep going back to tung oil.

See photos for examples. I can get as much shine as I want with more coats. The vase surprised me with how few coats it took to get that shiny. It is red oak, hard as a stone.

I like a smooth satin finish and apparently my buyers do too.

With lathe running at 800 rpm I sand my pieces to 220, then turn off lathe and wipe on tung oil with a rag until the piece is coated.

I then start the lathe and rub all over with more tung oil on a rag, then with a dab of tung oil on 320 paper sand all over keeping the sandpaper wet with tung oil. Then more rubbing all over with rag wet with tung oil.

I then have a look and if there is no build up of sanding dust and tung oil use an old athletic sock and buff at 1400 rpm until the piece is somewhat dry and shiny.

If there is build up I press hard with a roughish rag wet with tung oil to get it off.

If it is cold and / or damp, I will warm the piece wiyh a hair dryer between steps.

At the end of any session I can take the piece out of the chuck and set it aside while I do something else.

I will sometimes start finishing a piece at the end of a turning session and leave it in the lathe. Next day or later that day I will look at the finish and give it a buff with the athletic sock.

If it needs more finish I will run at 1400 and apply tung oil with a moistened rag, just enough on the rag to put on a thin film, but not enough to throw it off the piece.

When I have covered the piece I will stop adding tung oil and rub all over with the lathe running at 1400 until it begins to drag on the rag.

I then warm the piece further with the hair dryer and let it spin for a few minutes, then buff with the sock and the piece is finished.

For salad bowls I use mineral oil from a pharmacy sold as a laxative. It is much less than salad bowl finish from a turning supply. It does not get very shiny.

ogato
15th September 2015, 05:44 PM
No secret formulas or mystical ingredients for this lazy boy, I just use
KUNOS Natural Oil Sealer #244foodsafe according to the manufacturer, easy application and outstanding results (IMO)

Jeff

smiife
15th September 2015, 08:40 PM
No secret formulas or mystical ingredients for this lazy boy, I just use
KUNOS Natural Oil Sealer #244

foodsafe according to the manufacturer, easy application and outstanding results (IMO)

Jeff

I would agree with jeff ,! I used some u-beaut foodsafe plus
works really well :2tsup:

Mobyturns
17th September 2015, 08:17 AM
If you make your own "food safe finish" and supply the finished products to others - how do you know or prove that it is "food safe"?

Much lower personal risk from a product liability viewpoint to use a product supplied by a recognized manufacturer who certifies that the product is "food safe" in compliance with legislation & testing standards.

TrickinWood
17th September 2015, 11:10 AM
If you make your own "food safe finish" and supply the finished products to others - how do you know or prove that it is "food safe"?

Much lower personal risk from a product liability viewpoint to use a product supplied by a recognised manufacturer who certifies that the product is "food safe" in compliance with legislation & testing standards.

Wouldn't it be a safe bet, with 3 ingredients that are Food Safe, mixed together still making the concoction Food Safe ?? Its not like mixing Chemicals, where the compound changes once one is mixed with the other

wheelinround
17th September 2015, 11:13 AM
:2tsup:

Dean0
17th September 2015, 11:29 AM
Some good information posted so far. I knew about kunos oil but have never found any locally.

I I originally started making this as I had accumulated a lot of the ingredients over the years and it makes a good durable waterproof finish. Oh and it's free from the stock pile.

rob streeper
17th September 2015, 01:21 PM
Excerpted from Understanding Wood Finishing, How to Select and Apply the Right Finish, Bob Flexner, 2005,

Reading from The Food Safe Myth on p. 76,

"No myth in wood finishing is more ingrained in the psyche of woodworkers than the belief that oil and varnish finishes containing metallic driers are unsafe to eat off of or to be chewed on by children.

... Companies selling salad bowl finish have prospered as a result of this myth.

... Salad bowl finish is varnish!

...And varnish cures at a reasonable speed only if it contains metallic driers.

...the very finishes that are marked to be food safe and are promoted in woodworking magazines as a solution to the problem are themselves every bit as guilty of containing the same driers as the oils and varnishes woodworkers are told to shy away from.

... The Food and Drug Administration (FDA) lists all common driers as safe for food contact as long as the finish is made properly----that is as long as the finish cures.

... Let's finally put this myth to bed and use other, more legitimate criteria for choosing a finish."

I've used General Finishes Salad Bowl Finish (https://generalfinishes.com/retail-products/oil-base-top-coats/salad-bowl-finish#.VfojSH3wnMc), seems to work well but I have no idea if it is truly safe.
My preferred finishes are shellac, beeswax and now amber varnish. I think they look and feel great.

wheelinround
17th September 2015, 02:05 PM
I don't make these LOML picks them up from Woolies or Coles etc.

Almond Oil, Wallnut, Macadamia, Avacdo. So far I have found Walnut the best hardens to a nice finish depending on timber followed by Macadamia am on using Almond ATM none have gone rancid and of course all food safe as they are all used in cooking. The only hassle here is if someone who is highly allergic to nuts has a problem so far so good.:2tsup:

Mobyturns
17th September 2015, 09:51 PM
Wouldn't it be a safe bet, with 3 ingredients that are Food Safe, mixed together still making the concoction Food Safe ?? Its not like mixing Chemicals, where the compound changes once one is mixed with the other

It could mean that the mixed substances will not cure fully!

Most "natural oils" used as finishes include some form of drier to hasten curing. Even "environmentally friendly products" such as Kunos "ARDVOS Universal Wood Oil" and "Countertop Oil" list "and drying agents free of lead (Co, Ca, Zr)" as ingredients in the MSDS.

https://www.livos.com.au/shop/shop_image/product/37/MSDS_266_Jan_13.pdf
https://www.livos.com.au/shop/shop_image/product/48/MSDS_243_dec12.pdf

Uncured "natural" oils however may present an objectionable odour as they (may) go rancid and potentially may also create a nice medium to trap food particles to provide a culture medium for bugs to grow in.

I find the whole "food safe" discussion interesting as I have read a fair bit about "food safe finishes." Bob Flexner and many others say - as long as the finish has dried and any objectionable odours have dissipated it is unlikely that the finishes in common use by wood turners will present any creditable ingestion or allergy hazard.

Most of the fear about unsafe finishes is irrational.

We see all sorts of statements "FDA Approved for indirect food contact” etc but what does it really mean?

The FDA regs say "Resinous and polymeric coatings may be safely used as the food-contact surface of articles intended for use ... holding food .... in accordance with the following prescribed conditions: The coating is ... applied to any suitable substrate as a continuous film or enamel that serves as a functional barrier between the food and the substrate. The coating is characterized by one or more of the following descriptions: Coatings cured by oxidation. .... Coatings cured by polymerization, condensation, and/or cross-linking without oxidation."

Essentially anything that is listed in the regulation is permitted & there are plenty of listed descriptions that only chemists would understand as well as the "natural" oils. If you really want to nod off start reading,

http://www.ecfr.gov/cgi-bin/text-idx?SID=9a263b3e651e63eebe11bba4d72180a0&mc=true&node=pt21.3.175&rgn=div5
http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?FR=175.300

My point is - it does not matter what a turner says about a product or finish, they can claim it is "food safe" and it may well be but there will eventually be someone to challenge the turners claim. If its a responsible manufacturer like UBeaut or Kunos making the claim that a product is "food safe" they usually have the testing data & certification to accompany the product. One less thing to be concerned about.

rob streeper
22nd September 2015, 01:28 PM
Also very appropriate to this discussion is the USFDA GRAS (Generally Regarded As Safe) list. You still need to be careful however as the GRAS list contains substances known to be hazardous such as diacetyl (popcorn-lung - https://en.wikipedia.org/wiki/Bronchiolitis_obliterans) and helium (asphyxiant - https://en.wikipedia.org/wiki/Suicide_bag).

http://www.accessdata.fda.gov/scripts/fdcc/?set=SCOGS

(http://www.accessdata.fda.gov/scripts/fdcc/?set=SCOGS)

AngelaPetruzzi
22nd September 2015, 05:09 PM
The difference between food safe and certified food safewill come down to the end user. If you are finishing off something for yourself,then why not use olive or walnut oil for example...or any other coating. The issuestarts when one is selling a piece and calling it food safe. Then, one shouldbe able to prove it, either themselves or obtain the certification from theproduct manufacturers/retailers. If itcomes to the crunch, saying it is treated with olive oil only will not suffice unfortunately. When one uses e.g. Tung oil, is thisnatural tung oil or modified with varnish? And, what happens to those sensitiveto nuts since tung oil is derived from nuts.