7mm Pencarrow Loco Builds

[Peter Cross]

Hi Peter,

We normally sell by individual parts, retaining the unwanted parts off the sprue. This means we can supply spares to those who lose/damage those from our kit, or sell to others, without having to hold vast numbers of spare sprues. We haven't had time (and won't have for a while) to produce a priced on-line catalogue listing all that is available, so best to contact me via the website with your needs.

Richard

Many thanks Richard. I will need some parts probably next year. It will be for an X6 was going to be a K10 but I'll wait for that. But first I need to see all that is required, and check what castings are already in stock.

Sorry for going off topic Chris.

 

[Pencarrow]

No worries Peter, enjoying the posts. Good to see the Finney7 chaps able to help again.

 

[Pencarrow]

Looking forward to a time when I can get away from house DIY and towards kit building - a few questions for the collective...

I've read on a few build threads about folk not using the Slater's crank pins in their wheels and instead going for a larger diameter alternative. What are the benefits of doing this and who is the supplier of the alternative? (now I've looked for a thread that mentions them I can't find one)

Second question relates to some tools I'm probably overdue getting - a set of taps (for cuting a thread not water). Again lots of build threads mention casually in passing drilling holes and then tapping them to accept a xBA screw. Can anyone recommend a reasonable set? I presume they come in a full range of quality/price from the cheap junk to the full NASA spec. I'm after something for occasional use that will be good for years.

Final question for now relates to recommendations for a temperature controlled soldering station. I currently have 3 irons of varying ages, all Antex. A 25w low temp for white metal, a bog standard 40w and big blue - a 80w bruiser for jobs the smaller iron isn't up to (which is quite a lot in 7mm!).

Thinking about all the kits I have to build over the coming years, I'm thinking it's worth investing in a temperature controlled solder station. Are they worth it? Will I get better results? Which to get - as there seems to be a bewildering array of options? What sort of specification should I be looking at for 7mm stuff. I've seen a few recommendations for the Ersa i-con pico 80w but will this be OTT for me?

Sorry, lots of questions for you...

 

[Heather Kay]

I've read on a few build threads about folk not using the Slater's crank pins in their wheels and instead going for a larger diameter alternative. What are the benefits of doing this and who is the supplier of the alternative? (now I've looked for a thread that mentions them I can't find one)

I've seen this, too. I think it depends on what the loco will be expected to do. Slater's crankpins seem a bit weedy, but if the model is effectively going to spend its life pottering about at relatively slow speeds they ought to be sufficient. As to alternatives, well, a good source of 10BA steel bolts would be the answer, I reckon. Then, of course, you need to source suitable bearings, and make the adjustments to the waggly bits accordingly. In the end, it's your choice, of course.

a set of taps

Eileen's Emporium stock most of the sizes you'd probably find useful. Other suppliers are available, so it might be worth shopping around for prices. Don't skimp, but equally don't spend more than you think they're worth. Smaller tap sizes, as is the way of things, are more expensive. Sometimes, you will be able to buy the tap with a suitable clearance diameter drill: nothing worse than drilling out the wrong size hole, believe me! I've inherited my selection from Best Beloved, but I do intend on replacing the odd one I've managed to break.

I've seen a few recommendations for the Ersa i-con pico 80w but will this be OTT for me?

I asked much the same a couple of years ago. I was pointed to the Ersa range, and got the RDS 80. I have to say, I've not regretted it one bit. Again, like all tools, it pays to buy good quality if you can afford it.

No doubt others will throw their tuppence-worth into the ring in due course. Pay them heed, as I have done on many occasions. The WT Hive Mind is a wondrous thing.

 

[Paul Cambridge]

I’ve not got a temperature controlled soldering , but I did invest in a Resistance Soldering Unit about four years ago. I used mine in anger on my LSWR 20T Brake van kit and found it good for all the overlays. RSUs are not everybody’s cup of tea and it is worth having a go on somebody else’s first. You do have to make your own ‘earth’ plate as well. Having used the RSU it does have its place in the tool kit, but there are jobs where the iron is the only choice. RSUs are also very good at the invisible solder game. A bit more time to pre-tin, but minimal cleaning up. They are not cheap though. There is also the gas torch option where lots of heat is required. Not a lot of cleaning up again. I could do with a better quality one, but it will have to do for now; not a lot of need for heat when working in plywood gluing wagons together .

 

[Pencarrow]

Thanks Heather, very useful - what sizes of tap do you find most useful and do you use BA or M?

 

[Paul Cambridge]

Re BA taps. I’ve got a copy of the Dormer drill and reamer hand book. It specifies, amongst 1001 other things, clearance and tap hole sizes for threads. This is the page for BA threads.

 

[Heather Kay]

Thanks Heather, very useful - what sizes of tap do you find most useful and do you use BA or M?

I have BA exclusively, mainly because that's what I've got! I have found the 8, 10 and 12 sizes most useful. The 8BA matches what I've found most kit manufacturers include for fixings. 12BA is handy as it matches the Slater's crankpins so it's easier to make recessed crankpin nuts and so on. I think I have a 16BA, but it hardly ever comes out to play.

I think I would like to add some dies to the tool box. This is an idea that's a work in progress at the moment.

 

[oldravendale]

Chris,

The normal recommendation is to buy the best tools you can afford. My philosophy over many years where expensive stuff is concerned is buy a cheap set first (eg files and taps/dies) and as they break or clog replace with best quality singles. I suspect that few will agree, but that works for me, and some of the cheap tools I've bought are still going strong, probably because of their infrequent use. Most recently I bought a set of cheap metric taps and dies, and the infrequent use they receive makes them perfectly fit for purpose. The only items I'd buy top quality from the start are micro size drills and saw blades. If either of these are blunt they are utterly useless.

Whilst being aware of utter junk ebay can be your friend. I bought some taps and dies of undeclared mixed sizes on ebay a while ago, some of which were pre-used but some completely brand new. They were all by top makers and cost about a fiver.

A few years ago I bought an Antex temperature controlled soldering station but have found them poor at maintaining supplies of replacement parts - the plug in iron itself is no longer available which makes the station itself so much junk when the iron packs up which it surely will as the handle insulation goes brittle and deteriorates. When and if this unit gives up the ghost I'll go for an Ersa, simply based on the positive comments I've seen on here. I also subscribe to the gas torch as a useful tool and the resistance iron can be useful, but I'd not go for that immediately. Overlays can be fixed using a regular iron, but perhaps not as easily.

In general I find that the Slaters crank pins/bearings work OK, but I use bearings threaded 10BA on Walschaerts valve gear as I've had problems in the past with the crank unwinding itself and either leaving bits over the track (best result) or seizing up the drive (worst possible result). Threaded 10BA bearings used in reverse and countersunk in to the front wheels of most LMS designs also work well as there tends to be minimal clearance between the wheel/coupling rod and back of the cylinders/slidebar assembly. I don't know who can supply these, but I make my own by simply threading standard Slaters crankpin bearings.

At the end of the day the decisions about what to buy are yours, of course, and you'll have as many personal preferences as there are members of this forum, so you'll doubtless still be confused but on a higher and more educated level than when you asked the question......

Brian

 

[Paul Cambridge]

Whilst on the subject of taps, dies and drills, I find vernier callipers invaluable. I was really lucky when years ago work was selling off surplus measuring equipment. I bought a 300mm Mitutoyo dial vernier for a song. It was just out of calibration at that point. I’ve even used it on my recent 16mm scale laser cut ply brake van build; honest . You find that drills are not quite the diameter they claim . I also use the vernier for checking wire sizes and thin sheet material thicknesses.

Edit to add. I use Locktite 242 threadlocker to keep nuts on their threads. Mine was ‘out of shelf life’ from work, but there the specified strength was important. Years down the line it still works and is adequate for modelmaking.

 

[oldravendale]

In total agreement with Paul on that one!

B

 

[Pencarrow]

Thanks all...

Looking at taps, what's all this about taper, second and plug? Do I need all three for each BA size or am I looking at the wrong thing?

 

[Steph Dale]

You only need worry about graduated taps when tapping blind or deep holes. In most cases I've got only 1st (taper) and 3rd (plug) and only use the latter for functional threads.

There are other advantages to going to 10BA crankpins than those mentioned. Certainly breakage isn't one of them; if you break even a 12BA crankpin your chassis has bigger problems than just crankpin size...

I did a thread on why and how to use 10BA crankpins on WT a while back. When I get back to a PC I'll try and find it. Despite some of the ideas expressed in the thread it's actually a simple and painless thing to do.

At this rate I'll get you on to split axles for your next build; you'll wonder why you didn't do it earlier...

Steph

Edit: Found it: Tapping Slater's crankpin bushes for 10BA crankpins
It even seems to contain some good advice for tapping in general!

 

[mickoo]

Chris, as Brian mentioned, get the best you can afford.

For me I've migrated to, and existed on, a few fundamental basic items I now wouldn't be without.

A Proxxon drill.
ERSA 80W soldering iron.
Valorbe needle files.
A digital caliper, recently a 150 mm one from one of the big trade show stands, not as good as my original better 300mm was confiscated by Chinese airport security who considered it a weapon .
Taps I bought from a link Adrian Cherry supplied on WT at some point. I have 6BA through to 14BA, never used the 6 or 14, use the others all the time. 8BA to chassis fixings, 10BA for crankpins and other smaller details, 12BA for brake gear etc.
You'll also need two reamers, 4.00 mm and 4.80 mm again from a link Adrian supplied on here.
Some pin vices and a set of broaches are also advisable. There are two types of broach, ones just for smoothing, most common and ones for cutting. The smoothing ones will cut, especially in brass etc, but they tend to leave a raised rim around the hole, the correct cutting ones wont/shouldn't.
Broaches usually come with a small plastic handle, it'll break in time, at which point I stick them in a pin vice, much easier to handle, or if you're smart, stick them in the pin vice before they break.

Crankpins, I just use Slaters stock bushes, drill out and re tap to 10BA, you need to do the same with the wheel as well

Will any of these make you a better modeller, probably not, but they will almost certainly make it easier and significantly less stressful and being as this is a hobby we do for fun then stress should not be a factor, if it is then y'all doing something wrong.

Mick D

 

[Pencarrow]

Some excellent advice so far chaps, given it a quick scan in between washing primer out of paint brushes. Will give the posts a good read tonight over a well earned beer.

I think having the right tools is a godsend (once you've worked out what the right tools are!). Domestic DIY is king at the moment but currently in use and making my life a lot easier are a bench mounted chop saw, router, circular saw, cordless impact driver, big hammer drill, cordless electric drillsx2, and many hand tools. End results of the new doors and frames looking good, going to need the plasterer in for remedial work though...

 

[Paul Cambridge]

I’ve just done a search of the online MRJ index. Rod Neep wrote an article on the kit builder’s workshop back in issue 5. No doubt things have moved on considerably since then. The soldering station mentioned by Mickoo looks light years ahead of what we had in the 80s. He also wrote an article in Compendium 1 on a scratch builder’s workshop. Unfortunately all my MRJs are packed up, otherwise I’d locate them, have a read and possibly scan them (scanner is packed away....).
Footnote: damn the broken English house moving process . Rant over .

 

[Peter Cross]

I think the use of power tools is a quite recent phenomenon. I know my apprentices, have all reached for the power tools as soon as a job was allocated to them. I know for the first year or so I used to get some fine old looks on swapping them for hand saws and chisels. It was one of the hardest things for them to understand. That they needed to learn the job properly before taking short cuts.
Anyway back to the modelling. You actually need very few tools to build kits or scratch build. Having good tools is a very sound base, good does not necessarily mean expensive (Well not always). I ought to thin out my bench. Lots not used there, but looks impressive. As mills and lathes, both very useful, but can be a waste of money if not utilized properly. Even in my old place I often found that I had something in the drill to clean up, or a screw or wire to turn into something else, rather than the lathe. As for soldering irons. Now I'm retired, I'll be sticking to my old fashioned ones along with the resistance thingy. I've looked at stations but at the moment can't justify 500 odd beer vouchers. I also don't get on with plated tips. Much prefer a lump of copper filed to shape and binned when too short.

 

[simond]

8, 10, 12 BA taps, dies, tapping & clearance drills. Tracy tools in Dartmouth are worth a look.
I have a couple of sets of taper broaches, very handy. No idea where they came from.
I’m still living with second rate needle files, got a load cheap at the ME exhibition many years back. Couple of small “normal” files too, and an A4 sheet of MDF with emery paper stuck to it.
Variety of soldering irons including one that is about 3 oz of copper on a metal bar with a file handle, presume you heat it in a fire or the oven. Resistance thingy very useful - mine’s homemade. I have one of the old Weller pistol-grip induction irons which get hot in seconds too, it lives at my pal, John’s, very good for sorting out outdoor track repairs. Bit clunky for loco building.
Good pliers, Xuron shears, scalpels, Stanley knife.
And a trusty block of mahogany with odd holes all over.

Unimat lathe & Proxxon baby mill are nice toys and do get used, but are probably overkill, if the kit’s any good you don’t need them.

Best
Simon

 

[Peter Cross]

Re BA taps. I’ve got a copy of the Dormer drill and reamer hand book. It specifies, amongst 1001 other things, clearance and tap hole sizes for threads. This is the page for BA threads.

View attachment 94183

I'm a Zeus man myself.

 

[Pencarrow]

Had a play with the new Christmas present this afternoon.



Very impressed with the speed it heats up and how it keeps pumping heat into large lumps. I can see why it was recommended!