Renovating Primus Oil Burners.

Taranaki Daily News, Volume XXXXV, Issue 247, 17 November 1903, Page 4

Renovating Primus Oil Burners.

Probably everyone who has anything to do with Primus oil burners will have had trouble with them at some time or other, and no one appears to know how to remedy the fault of a sooty flame. For this reason we re-publish the following very instructive and valuable artitle written by Mr Henry Greenly, for the Model Engineer and Electrician : Having had a "Primus" oil stove in pretty constant use for domestic and other purposes for the last three years, I have found, in addition to similar experience with these burners in model work, that if the stove be alight for one or two hours daily, after twelve to eighteen montKS' service, the burner, in the words of the household authorities, shows siflps of " going wrong." A year and a half ago. When the original burner of the stove above mentioned developed these symptoms, it was, after considerable experimenting—making red hot, scraping brushing* and blowing through with eompressed air, fitting with .new nip*pies and the in feveur of a brand ,new burner, which, I may say, worked admirably until lately, when the flame became white and sooty, and did not burn . with the usual pretty colour. A few weeks before the drastic, 'but successful remedy to be described, was applied, a new nipple was put in, with no, appreciable alteration in the quality of the flame. Feeling sure that the trouble was not due to inherent defects through hard usage, but by reason of the I greatly increased consumption' of oil, that both the vaporising surfaces inside the burner and the baffling plates outside (which in a large manner complete the ignition of the gases) were in the one case coated with a non-conducting deposit from i the oil, and in the latter with accumulated dirt and oxidation, I • thought that if complete cleansing inside and out could be accomplished, the burner would work just as well as when new.

My experience in hard soldering making me well acquainted with the cleansing properties of diluted sulphuric acid when applied to brass and copper, I decided to try the effect of a pickle consisting of acid 1 part, and water 10 parts. As many wh» are likely to make up this pickle may not be amateur electricians, and not know of the proper 'way to dilute sulphuric acid, it may be as well to mention that the acid should be poured gently into the water, and on no account should water be added to the acid, else a serious accident may occur.

Taking out the nipple, and removing the loose inner ring and cap, I placed the burner ring and eap in the fire, which was at the time bright and clear, and, when the parts were at a dull red heat, I took them out, dropped into the pickle—keeping clear of splashes, of course—leaving the parts there for about a quarter of an hoijr. On removing, I found the outside of burner <juite clean, the dirty deposit inside being as far as I could see either completely removed or loosened. The small holes in the muffler or silen»er of the burner, which are so apt by constant use to become blocked up, were also clear, and on thoroughly rinsing the burner witii water and putting it together, replacing the nipple, it was found that the burner .worked just as well as 'originally—indeed, it was declared bptter than when new. These few hints on the use of "Primus" burners will apply equally as well to the other typ«s of Swedish paraffin burners, and should lead those who employ these burners for firing model bcSleis and other purposes, not to Jiastily condemn the burners as untrustworthy and a nuisance. . I may again urge readers to prevent, flooding of the burners with oil whilst cold, as this is conducive to trouble through minute particles of dirt being carried to the nipple ; and to present dirt in the tank by filtering or straining the .supply of oil. The caps also become loose through variations in the expansion and contrastiou of the various parts, and it advisable occasionally to make these fit tightly by chucking in the lathe and spinning down, the v flange with a smooth hand tool or burnisher. The burner above-mentioned hae been working daily for about two months now , without trouble, not having been pricked out more than a dozen times during this period. Whilst, of course, the acid will not chemically combine with the carbon of the internal deposit, the organic matter is eaten away and the deposit loosen«d. A good way to remove this in extremely bad cases is to repeat the heatings and to rinse the burner by placing it on the house tap and passing a strong stream of water through it. Even if this is not done, tho porosity of the deposit which may remain will allow the oil to come in contact with the burner, and will work very well, considering. To conclude, I may add that the matter has received the support of the London importers of these stoves and burners, and I have had the opportunity of practically demonstrat- '• to them the value of the process eansing on their own premises.