From: Think Tank Subject: Think Tank Vol.0093 14/10/2001 Think.tank@tesco.net ------------------------------------------------------------------------------- MODELLERS' INDEX 1: Where is Tassos Tsiplakos? 2: 1/35 US half-track tracks 3: Health warning regarding casting materials 4. Allied Armies Italy formation sign -------------------------------------------------------------------------------- TRADERS, ANNOUNCEMENTS & NOTICEBOARD INDEX 1: Next edition -------------------------------------------------------------------------------- MODELLERS -------------------------------------------------------------------------------- 1) From: Grant Parkin [granty_p@hotmail.com] Subject: Where is Tassos Tsiplakos? Dear Robert and the 'thinkers', I was wondering if anybody out there in cyber land had heard from, or seen, Tassos Tsiplakos recently? The reason I'm asking is that about three months ago I sent some books to Tassos, who was to send to me some kits in exchange. The last I heard from Tassos was that he'd got the books, but I've not had anything in reply. Is Tassos unwell, working abroad (away from Greece that is), or, heavens forbid, dead! Tassos, if you're out there and reading this, please get in touch, and let me know what's happening. Grant. -------------------------------------------------------------------------------- 2) From: Paul.middleton [paul.middletonmafva@tesco.net] Subject: 1/35 US half-track tracks Just a quickie, Mil Mod arrived yesterday, and I noticed in F & F Models advert that they stock the Castoff range. Amongst the modern stuff is a set containing tracks and front wheels for the US halftrack series. Price is £8.00 plus 10% postage. I don't remember seeing the set, has anyone tried it? F & F Models are at www.fandfmodels.co , e-mail john.burrows3@virgin.net Cheers, Paul Middleton. -------------------------------------------------------------------------------- 3) From: john.baumann@talk21.com Subject: Health warning regarding casting materials Further to your recent Think Tank correspondence on the subject, here is a follow up to my own recent Tankette article, concerning home casting. This response highlights some of the dangers posed from the modern materials on offer to the public. The following is meant to alert all concerned. Regards, John Baumann Subject: Casting made easy From: Andrew Telford (Rig Paramedic) To: "'john.baumann@talk21.com'" Hi John, I meant to pass this info along to you sooner, however it slipped my mind with all the excitement going on when I was at home. It concerns your article in 36/3 on casting with 'Isopon body fillers'. As part of my job onboard, since nobody is 'maimed' every day we usually have a dual role, mine just happens to be the COSHH Co-ordinator (Control of Substances Hazardous to Health). One of my duties is to assist individuals complete what we call a COSHH Assessment, basically it's a Risk Assessment with regards to the use of chemicals and hazardous materials, and these are a legal requirement. Moving on........ Isopon body fillers 40, 50 etc are supplied to industry and obviously the public, regulations state that when a product is supplied to industry it must be accompanied by a 'Material Safety Data Sheet' which is a 16 section document on the product with a whole load of useful information. Unfortunately 'Joe Public' tends to get a diluted version either on a small label on the product or if your lucky some instructions in the packaging. This information tends to be the bare minimum to satisfy the regulations and 'cover their ass' in the event of a claim against them by an individual who has used the product (in)correctly and suffered ill effects in doing so. Isopon body fillers (also most other body fillers) contain Styrene; this material has an MEL (Maximum Exposure Limit) applied to it, this is a limit which is legally binding under the COSHH 1999 regulations. Styrene is classified as 'Xn' Harmful. A MEL is applied to a substance "where there is serious concern about the possible health effects in workers" MELs are most often allocated to carcinogens, respiratory sensitisers (asthmagens) and substances which no threshold level of exposure for the effect can be identified and for which there is no doubt about the seriousness of the hazard(s) posed by the substance. The Isopon range has an MEL of 250 parts per million over a 15 minute short term exposure limit; this means that if an individual is working in an atmosphere of 250ppm he has 15 mins in a 24 hour period, and that's his lot! He cannot take an hour off and then have another 15 mins and so on. The regulations also allow for an 8-hour time weighted average,(100ppm) this means if the level is less than 100 he can work for 8 hours without suffering any ill health effects. Now looking at the MSDS I have for Isopon, Styrene odour is detectable at 25ppm, at 200-400 there is a transient irritant effect on the nasal passages. At 400-1000ppm systemic effects such as dizziness, nausea & headache increase, 800ppm and over becomes intolerable to the mucous membranes, at 1,000ppm and above death will occur in less than 1 hour. On a plus point there is no evidence to show that Styrene is carcinogenic to humans. So what does this mean to our chap in the 'garage'? If he has irritation to his nasal passages he is in an atmosphere of at least 200ppm probably greater, he's got 15 mins max to err on the side of caution. If he's feeling nauseous maybe a headache he has already received his maximum exposure to Styrene for the next 24 hours. Job stopped. If your ventilation is so good you can't smell it, then great, fill your boots! 'Nipping in and out' will not reduce exposure,15 mins exposure in one hit is the same as 15 mins exposure divided into 5x 3 min periods over say 1 hour. It is the exposure to the hazardous substance over the time frame that is the important issue. Exposure is cumulative with an MEL. Obviously no one is going to enforce this on 'Joe Public' hence the disclaimers on the packaging! Reducing the exposure as you rightly stated can be achieved by means of ventilation, natural or forced extract, a fan blowing over the work area towards a door or window is best. Working in a confined space is a definite no-no, unless of course you've got access to a fully sealed chemical suit and an air fed respirator (NBC suit & SR10 would do the trick!). The use of a face mask is a further method of reducing exposure (inhaled), ensure the mask you have is suitable for the product, most masks available to the general public at B&Q etc are purely 'dust masks' for 'low hazard dusts' and are not intended to filter chemical particulates and gasses. The mask should be to standard EN405 or EN149 and will be further categorised into FFP 1, 2 & 3. The higher the number the higher the protection. EN 405 are filtering half masks for gasses and particulates, EN 149 are filtering facepieces for particulates. Isopon fillers and most body fillers are specially formulated to be sanded wet, not dry. Sanding dry will produce 'dust clouds'; dust in the correct concentrations must be regarded as a potential danger to health. Obviously we are not going to be producing great clouds with the amount of sanding we are talking about, however modellers tend to be very close to the piece they are working on and consequently will probably inhale more dust than would normally be expected. Sanding of Isopon requires a face mask of EN149 FFP2S (S standing for solids) which is a higher protection level than just for mixing. Styrene is also a 'Skin Sensitiser' so appropriate protection should be worn when handling the product; those individuals with skin complaints or other allergic effects should avoid using the product. Polythene gloves are recommended whilst sanding the product. I hope this is of some use? Regards, Andrew PS: "Silicone sealant and some resins" do not produce fumes. 'Fumes' are produced when solid materials are heated to a temperature at which they vaporise, the droplets condense forming small particulates. Silicone sealants produce technically a mist; mists are small droplets of liquid material, which may also evaporate i.e. solvents -------------------------------------------------------------------------------- 4) From: Listmaster] Subject: Allied Armies Italy formation sign Can anyone suggest the formation sign which would have been carried by formations attached to HQ Allied Armies in Italy (AAI) during the latter part of 1944? This is not a theatre on which I have much information and I am trying to research the markings carried by vehicles of 12L at the time, which was an armoured car regiment. Thanks Robert -------------------------------------------------------------------------------- TRADERS, ANNOUNCEMENTS & NOTICEBOARD -------------------------------------------------------------------------------- 1) From: Listmaster Subject: Next issue Due to an imminent departure on holiday in search of military museums in the Sussex area (or at least any I can get away with), the next issue will not be out before next Monday (22/10) night. Robert -------------------------------------------------------------------------------- Robert Lockie (Think Tank Listmaster) Back issues of Think Tank (thanks to Shane Jenkins) can be found at: http://www.tac.com.au/~sljenkins/thinktank/thinktank.htm -------------------------------------------------------------------------------- End of Volume