21st March 2020
In addition to the obvious requirements necessary for our hobby e.g. models, engines, radio gear etc we also require a fairly long list of additional bits and pieces. These include adhesives (henceforth known as ‘glue’ to save ink), tools, mechanical fittings, covering, paints, wood, engine spares and many other general use items for building, maintenance or repair.
These are available via model shops but these days the local model shop is becoming a rare beast. Established model shops with online access provide an excellent service and, in addition, other sources of our supplies (e.g. the building trade) can be found.
This note is to set the ball rolling concerning
a) where is it possible to buy what we need
b) look at alternative materials & components
c) do these actually do the job ?
It’s based on members’ input so, hopefully, additional contributions will continue to develop this into a useful reference for all. Obviously any costs quoted are applicable only at the time of writing but they can then go down as well as up.
This list includes some suppliers’ names but these aren’t specific recommendations but, rather, just suppliers that members have used, and whose products seem to do the job ok, or they are just examples from the internet. If you know of other suppliers please pass this info on for inclusion; the more the better.
If enough members are interested in particular materials or components then members getting together for bulk buying may bring prices down even further.
Beginning with a primary topic of interest - glues
A primary aeromodelling requirement is to join wood. If the glue is stronger than the wood itself then it’s considered strong enough. (i.e. if you pull a joint apart does the glue itself separate or does it pull the surface off the wood). All the cyanos tested and noted as “ok” satisfy this test on balsa, basswood, birch ply & lite ply and spruce..
The factors not considered here include cure time, ageing, non-wood material surfaces etc. but if anyone would like to offer advice on the best glue for these please do so.
A common size is the 2 oz or 50 gm size and we’ll look at this as a reference. The highest price seen online so far is £50 ! Well known US brands are available much cheaper from model shops at around £12 and do the job, of course. There are even cheaper brands online but are they ok ?
There’s Vital bond at around £7 for the 50 gm size. (this works fine). Untried sources include Sussex Model Centre Grip at 4.99, Rapid RC own-brand cyano at £3.50 for 50 gm, all in several viscosities including very thin. There are many other varieties online of course, have a look.
Locally, If you only want a medium-thin viscosity Tool Station has 50 gm for £2.63. and Screwfix do 50 gm for £1.99 (this cyano works excellently).
At these cheap prices it’s worthwhile getting a sample and testing it yourself to make sure it does what you need.
PVA (or white wood glue) comes from many sources. My personal favourite is Evo-stik PVA, the one in the green bottles. It is not the cheapest but, overall, it seems to be a good all-round glue in terms of grab time and strength. Extremely strong if applied with clamping pressure (pulls the surface off birch ply).
Also, one not so obvious use for PVA is as a one-time heat activated contact glue.
Commonly accepted as probably the strongest glue available to us (see footnote below). Comes in a variety of sizes and curing times. I usually use the epoxies available online from modelling suppliers (e.g. DeLuxe adhesives) as I use so little (as, I guess, do most). Anyone any experience of others ?
These include aliphatic resins, (e.g. Titebond) similar to PVA, and available through many outlets, and the Urethanes (e.g. Gorilla). Has anyone any experience of buying and using these ?
For modelling a thin nozzle is ideal to ensure precise placement. Fine tapered nozzles are available online for as little as £1 for 10. A metre of small bore PTFE tube costs about £1 and does as an extension for about 30 ‘nozzles’.
A problem often encountered is preventing glued work sticking to the plan or work surface. Kitchen clingfilm helps but is not completely “glue-proof”. The most glue-resistant material I’ve found is the clear backing from Solarfilm. Don’t throw it away.
Footnote on glues
I made a quick comparison of cyano v. epoxy on beech (that’s a very hard, dense wood), using 1-hour epoxy (overnight cure) and the cheapest (Screwfix) cyano.
The epoxy bond broke relatively easily using just my hands, and the epoxy itself separated. I could not break the cyano bond like this, I had to put much more effort into it and a thin layer of beech came away with the cyano from the wood, just what was required..
However, another test where the epoxy was gently warmed with a heat gun after application in order to help it soak into the wood surface produced a bond as strong as the cyano. Technique can be as important as the glue type on certain woods.
Tufcote (a commercial furniture varnish) used to be a very good fuel-proofer but since it changed its formulation it no longer seems to work as well, it goes tacky. One
alternative that does seem to get good reports, and seems to work, is Rustins Plastic floor coating, a clear 2-pack which, when thinned, brushes on superbly over Halfords acrylic spray paint, making model finishing easy.
For engine bays, Halfords satin black engine enamel is proof against raw petrol and up to 10% nitro glow fuel (maybe more). They also have a clear acrylic spray described as “petrol resistant“ (may possibly be in the motorcycle section).
A useful servo fitting, especially for throttles, is the connector consisting of a brass body with a hole through it for a wire pushrod, with a threaded shaft that goes into the servo arm hole where its held with a locknut. Schematic shown here -
Each connector consists of the brass body, the locknut and washer and a screw to clamp the wire. These can retail at c. £2-3 for 4 or thereabouts. I bought 100 sets of these for about £7.50 including postage from China.
With the recent demise of Solarfilm a new source of covering film is required. Mel Turnbull showed me a model covered in Hobbyking film costing £8 for 5m (less than cost of Solarfilm for 2m !). It looked fine and Mel says it goes on ok.
RCLife does covering film at £20 for 10m, definitely worth a try.
For vintage models, polyester dress lining has been suggested as a possibility. This will need an adhesive for attachment (e.g. Balsa-loc or similar) and then some lacquer finish to seal the weave. Procurement new from a shop rather than from the local wardrobe is recommended.
Useful for exhausts etc. Kits to do this requiring only a simple gas torch are available online from Durafix and Alutight. Seems to work, Alan Payne and Phil Lee have used Durafix.
Lipo battery checkers
These are available on Ebay for £1.52 each (order of 4 = £6.08 including postage from China !). Digital readout of 2-8 cells with programmable low voltage warning buzzer.
These are available on Ebay from many sources at a fraction of the cost of proprietary parts in the UK. For example, an adapter lead for a common rc brand costs up to £15 from the shops while the necessary components to make your own cost 65p (including postage)
Most bearings used these days in model engines are standard sizes and can be sourced from specialist bearing suppliers (e.g. Simply Bearings) at considerable savings. Even top spec branded bearings cost just a small premium.
Carbon fibre tube or rod has many uses in a model. Other sources, possibly local, are kite or archery suppliers. These outlets use carbon rod and tube up to about 10mm.
Important : Combinations of paint type and fuel proofer (if any) always have to be carefully chosen for compatibility and to suit the fuel being used (petrol/glow, nitro/straight etc). There’s too many combinations to list here, other club members are probably the first port of call for advice on this topic
Larger quantities of paint are available from paint specialists in Nuneaton. (Alan Payne has info).
For small amounts of aluminium, brass and other useful metals, try "Rapid Metals, Colliery Lane, Exhall ,Coventry". They will supply offcuts or size required.
As a main component of traditional aeromodelling many varieties of wood are used, including balsa (of course), bass, obeche, spruce, pine & birch (ply), and beech (bearers).
Here my recommendations probably go against the grain (so to speak). Wood is a natural material and quality is hugely variable. Is the grain straight, are there any imperfections (e.g. knots), is it dried and stable or likely to warp, is it cut accurately to the size you want, what grade is it etc (balsa varies in density by a factor of about 9)
My opinion is that it is best to go to the specialist supplier in the modelling trade who will, at least, be supplying wood that has been inspected for the above properties and be of a suitable grade and to (relatively) accurate dimensions.
Nuts & bolts etc
These are available in small packets for relatively low prices but savings can be made if bulk buying.
Specialist suppliers such as BoltBase or Shop4fasteners can supply all types of material and size of screws etc (e.g. 150 x M3 washers for £2.25, 50 x 3mm stainless allen bolts for £2.70). They also have fasteners in unusual metric sizes (e.g. 2.5, 2.6 and 3.5 mm) often found on Japanese engines and radio gear.