Casting Filler?

Many years ago, I had a tin of casting filler from Myfords, to smarten up my ML7 lathe. At last I am getting around to restoring my ML7. I have long ago lost the tin. It was mainly coloured black with some red and yellow. I think it had the picture of an imp on the front, although my memory may be at fault. The name was something like Trimar------?

Does this ring a bell with anyone and is the product still available? I ask because the guy responsible for preparing the lathe castings for painting, said it was by far the best product for filling castings. You might be surprised at what a Myford bed looks like before it is filled. There is quite a lot of filler used before it is passed for painting!

Am I being too fussy here and should I just use car body filler for my restoration job?

Andrew.

I think you will find the product was made and supplied by Trimite in Uxbridge. I worked there for some years.
we supplied nearly all the machine tool manufacturers in the UK and some overseas. All their cans were black with their logo in red and yellow.

They amalgamated with Weilburger a while ago but you will find them under the Trimite name, now located in Hayes Middlesex. If you call their technical advice centre you might be able to track down the product they sold to Myford in Nottingham.

Mono

**LINK**

Ive painted alot of old machines and i always found car body filler a pain to sand and it also shrinks. I tend to only use it on big defects ,the rest i just use that fast drying high build zinc primer (far easier to sand and stays put better.

If that is the same crew as supplied Raglan with surface coatings, don't bother. They only supply to industry, fail to respond to emails, etc. Basically don't want to know, or hear from, individuals. Car body filler is the best bet. Used by many for years and years.

Edited By not done it yet on 19/11/2016 14:10:15

It amused me when recently someone posted a moan that a casting on a Chinese lathe had filler on it. Generally only better quality items have the castings tidied up before painting...

Neil

I've no connection to either company but Rapid Electronics and I'm sure loads of other companies sell Loctite EA 3471 or EA 3479 metal filled compounds. The aluminium variety worked a treat in reclaiming a porous casting for me, the only downside is the cost if it's just for cosmetic reasons. (allegedly some humans spend more on beauty products every week !)...........DDT

Edited By DDT on 19/11/2016 17:02:07

I have a tin (about 800g) of Scols Super Iron Cement, it's a grey powder that is mixed with a small amount of water to make a putty .

Ian S C

Was not water glass once used to fill aluminium casting defects? I think I was casually told this during my apprenticeship when trying to cast a screwdriver handle. I know that my mother used it to preserve eggs before we had a fridge when I was a kid.

JA

Hi, it's not only castings that get filler before painting, I've seen industrial machines where thick steel plates have been profiled out with Oxy/Acetylene and were filled with body filler where the cut gouged out a notch along the edge, due to impurities in the steel. It's not until the paint gets chipped over time during use, that you are able to notice them.

Regards Nick.

When I was a lad common putty was used as a filler, but not mentioned. Water glass ,sodium silicate from memory, mixed with iron filings also common. The iron rusts and the mix goes hard, more expensive than putty tho'. Is good for egg preserving also.

Aha. Sodium silicate / water glass! Best used for making chemical gardens. That takes me back a few years...

The Mercans seem to love "restoring" old machine tools and being Mercans, they care more about looks than action. From what I've seen over on hobby-machinist.com, the preferred method is to use body filler to get a smooth finish, then paint over. The results are often pretty impressive but I'd rather spend the time and effort fettling the mechanical parts myself.

If you want to make a filler that easy to sand then mix epoxy with glass bubbles . It a filler used in boat building.

Some years ago I rebuilt a milling machine and filled the castings with a product called Belzona this firm have agents all over the uk

For traditionalists:

• Thick paste with water of : Sal Ammoniac (Ammonium Chloride) 2 parts, Flowers of Sulphur 1 part, iron filings 80 parts
• Expanding Alloy: Lead 9 parts, Antimony 2 parts, Bismuth 1 part (by weight).

Take care if you come across an old casting that appears to have been beautified with solder - Antimony is poisonous.

Dave

Not as poisonous as the lead

Well, maybe. My book gives an LD50 of 100mg/kg for Antimony (rats), whereas Lead 'just' gets a mention as a carcinogen and teratogen. Both are more dangerous when heated and both make many poisonous compounds. Where I am on thin ice is that the Antimony is in an alloy - might be trapped like Mercury in fillings. Lead is cumulative though. Needs to be tested - can you suggest anyone to experiment on!

Wkipdia is interesting, it says:

"The elemental antimony metal does not affect human and environmental health. Inhalation of antimony trioxide (and similar poorly soluble Sb(III) dust particles such as antimony dust) is considered harmful and suspected of causing cancer."

en.wikipedia.org/wiki/Antimony#Precautions

Neil

My source is the 5^th edition of ‘Dangerous Properties of Industrial Materials’.

Heavily abbreviatiated:

ip = ‘intraperitoneal’, sc = ‘subcutaneous’, im = ‘intramuscular’, LD₅₀ = concentration required to kill 50% of a population, LD_LO is the lowest published lethal concentration, THR is the summary toxicity statement, acute unless otherwise stated. HIGH means ‘Capable of causing death or permanent injury due to the exposures of normal use; incapacitating and poisonous; requires special handling.

For Antimony:

Acute tox data: Oral LD₅₀ (rat) = 100mg/kg; ip LD_LO (rat) = 100mg/kg
THR = HIGH via oral and ip routes.

In comparison, Arsenic:

Acute tox data: im LD_LO (rat) = 25mg/kg; sc LD_LO (rabbit) = 300mg/kg;
THR = HIGH via im and sc routes. A poison.

Tasty stuff!

Dave

When I was at school we spent the last few days of the school year stripping, and painting the workshop machines, the old Harrison lathes seemed to be more filler than casting, there were more holes than Swiss Cheese.

Ian S C

"Toxicity" is not a simple term. Salt is toxic in large quantities but essential in small. Similarly, many other "toxic" elements are essential for correct functioning of the body. And there are a lot of different "toxicities".

Much of the LD50 toxicity data is based on (lethal) injections into rats and while they give a fair indication of the likely toxicity in humans, it's not always the case. We have not been allowed to carry out the same tests on humans, even in the interests of science. Either way, we are very unlikely to find ourselves injected with 10g of Antimony (100mg/kg x 100kg) into the peritoneum - and if we did, we'd probably get down A&E before too long, to get it fixed.

The elements we call "heavy metals" tend to bioaccumulate in the tissues and bones. These may not kill us immediately but cause some pretty unpleasant effects. LD50 data is not particularly helpful there unless you are trying to end it all quickly. Metalloids (including arsenic) and radioactive elements also have undesirable effects.