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[RipSlider]

Hello all.

This is going to seem an incredibly obvious question, especially as I am on something like my 9th model, but I realised last night that I am just NOT a very good model builder.

As tyou may know, I am working on a PCF river boat at the moment. And, having put a few solid weeks of work into it, I last night steped back and gave it a critical look. And the results of this is that, I realise, I am rubbish.  :(

So, before I go any further, I thought I would ask a series of Back to basic's questions, to work out what I'm doing wrong. Once I've worked it out, I'll then fix any issues that I've currently got, and start onwards properly.

So what's my first issue? Wood.

my joints are, for want of a better word, appaling. It's very much touch where it fits. Nothing seems to have right angles, and until now, I haven't really minded, as I just fill in any gaps with Green Stuff. However, the entire boat is starting to turn green, and therefore, there is obviously an issue.

Up until now, i've put up with this shoddiness. With enough green stuff and sanding, I can bodge a good looking job. And the fact that my friend has 20 years of working on car body work means that by the time he's prep'd a model and then [painted it up for me, it looks amazing. But this time, I want the model to be good.

So, and I'm cringing asking this, how do you guys go about doing joints?

A few exaples:

1) I'm fitting the combing to the deck at the moment, so that I can slide over the super structure. The deck is ply, and thin, so I'm adding 3mm sq wood below the deck in order for it all to be able to be glued up. Even these trvial joints are awful.

2) angled joints: I've run beading all around the inside of the hull in order to have something to glue the deck actually on to. At the bow, there is a fairly tightly angled joint. Once agin, this was incredibly messy, and so I just filled the gaps with Green Stuff, and filed down.

3) I take a, usually strange, shape from a plan, and mark it onto, for example, a piece of ply. Hull formers are a good example. I run a jig saw around the outside, then use my scroll saw to cut into the lines itself. However, I usually end up with some sort of dreadfully wobbly, unsymetrical shape. So it can often take me 4 or 5 cuts to make a single former. I see pictures of other peoples cuts on this site that look as though they were done with a lazer.

Here's my process:

1) Offer up wood to area to be cut. Cut slightly over sized, using stanley knife. ( or scalpel if wood is soft )
2) offer up now shorter piece of wood again. Use pencil to mark off a more accurate size, by eye.
3) Cut
4) check
5) trim anything as required
6) glue


For cutting out shapes on ply etc:
1) trace shape onto tracing paper
2) Glue tracing paper to wood
3) Run jig saw around shape, leaving 1-2cm on the outside.
4) use a scroll saw to cut along the actual lines of the paper

(I'm wondering if others cut a little over sized, and then sand to shape?)

Now, this is obviously not great. Using this method, I'm not ever making accurate 90 degree cuts accross the wood.

So, i'm wondering if you can walk me through your own methods?
Do you use a mitre block? t sqaure for all cuts etc etc?
Cut with a scalpel? Razor saw? Stanley knife?
What sort of sitting, working position do you have? I.e are you sitting above all cuts, to the side etc?
Do you measure everything? If not, what don't you measure? How do you know where to cut etc?
How do you work out what angles to cut when you are making angled joints? By eye?


As you can tell by my questions, I'm looking for really detailed information about your process.

Also, feel free to take the mickey. I know it's a ridiculous question to be asking at this stage of my modelling career, but I rather fix the issues than keep sailing models I'm not happy with.

Thanks for any advice.

Steve

[tigertiger]

You are not alone Rip

Eevn though I cut with a Jap saw and a small mitre box, I still have to sand to shape.
And for moe complex shapes in corners, I have to do it with cardboard 3 or 4 time to get it right, then I use this as a template to cut the wood. By 3 or 4 times, I mean I have to scrap it and start again.  ::)

So any tips given will be used at my end as well. ::)

[boatmadman]

I have the same problems, but I have improved (I think!) just by practise.

 Angled cuts - templates in card first.

Square cuts - I use a small engineers square, held above the cut line by a thin peice os ply so the saw blades dont get blunted, and for small cuts use a razor saw. Even so, the cuts are never truly 90 degrees!

I often use a stanly knife on soft woods - lots of light strokes along a steel rule clanmped to the wood.

Work position - always above the work if possible, with eye line along cut line, and saw ,arm and shoulder making as straight a line as possibe - not easy!

Cutting shapes - I use a fret saw, cut slowly, with the wood well clamped. Cut close to the line and finish with a razor plane and/or sandpaper.

My razor plane is probably my most used tool. If you havent already got one, consider getting one, they arent expensive.

Work 'with the wood' not against it - by that I mean, always try to cut down the grain, it minimises splitting. When cutting across the garain, clamp tightly onto a clean backing piece, this will minimise splitting on the underside, do the same when drilling wood, always use proper wood cutting drills.

The best advice is practise and lots of it.

Hope this helps a little.

Ian

[Bunkerbarge]

You certainly can't beat practise but there are one or two usefull pointers to help you along the way.

1)  Use good quality, sharp tools.  Never be tempted to buy cheap crap because they will cause you more grief in the long run.  I use a Stanly knife, because it has a nice big handle, for ply along a steel rule and on one of the green plastic cutting boards.  I use a fine razor saw for most stock woods, avoid junior hacksaws as the blade is too thin and it will not stay true through out the cut.

2) Maintain a neat and tidy work area.  You will never be able to cut in the most comfortable manner if your position is constantly being compromised by rubbish on the work top.  Keep the area clean and tidy.  I always have a vacuum cleaner behind me while I am working and I clean up a mess as soon as I have made it.

3) Think about what you are doing before you commit to cutting.  You have to think of what the possible mistakes are before you start to cut, then do what you can to avoid it.  If you have a piece of thin ply and you are assuming that the edge you want to cut at 90 degrees to is straight then check it first.  If you are unsure trim it off with a steel rule and stanly knife so you know the edge is then true.  Mark out with a small square and then cut your 90 degree line.

If you want to join two planks at 90 degrees what is the easiest way to cut them?  Cut them together in the same operation, with the planks set at 90 degrees.  That way even if the angle of the cut isn't perfectly 45 degrees the planks will still be at 90 degrees.  If you do this then you must mark the planks so that the corrects bits are joined together.

I would make sure that you have a good cutting board, preferably mounted on a peice of stout ply or board so that you have an available edge to work with, a small try square, steel rule, 0.5 mm propelling pencil, dividers, compass, stanly knife, scalpel.

With these tools, a nixce clean working area and a bit of pre-thinking and planning you should be able to produce some nice neat joints that will surprise yourself.

Set yourself some tasks and exercises to complete to practise your skills and you will soon start to get things together a bit neater.

[boatmadman]

Just to add, a set of really sharp chisels are invaluable. When they are properly sharp you can shave off slices so thin they are nearly (but not quite) transparent.

i sharpen mine using a sharpening guide on diamond encrusted sharpening pads, working up to ultra fine. Then I polish them on a peice of leather glued to a flat piece of wood. Use the back side of leather, the rougher side, and metal polish. keep going until the edge has a mirror finish - you will be surprised how much sharper it is than without the leather strop.

Ian

[alan colson]

I always build boats for the stand off class, the futher you stand off the better. But I enjoy sailing them, especially in competitions, steering events and scale sail. It's the social side of things I really enjoy, a good chat, a laugh and a joke with my mates. If I want a good boat for some of the shows I go to I cheat and buy them secondhand, but be honest with the punters and tell them, they still enjoy looking at them close up and enjoy them on the water.

[Bunkerbarge]

Have a go at making something like these packing cases.  They are really simple and can basically be made up as you go along.  They are basically a ply box with deck planking glued to the outside to look like packing cases but in fact house a reciever and a couple of speed controllers.

Another very valuable piece of kit I keep onn the bench is a MDF model base of about 6" length or so with a peice of fine wet and dry glued to it.  I there for have a nice flat abrasive face available on the work bench at all times.  This is really usefull for checking that things are flat and that edges are straight before glueing together.

[HS93 (RIP)]

Bunkerbarge

Any chance of a couple of pictures of the rowing boat with the oars on so I can see how the mechanism works . 

Thanks Peter

[Bunkerbarge]

Not at the moment I'm afraid.  I'm at work until mid December and I don't have any pictures of the boat with the oars fitted with me.

An interesting feature though is that the mechanism generates an eliptical novement as opposed to the normal circular shape so I am hoping for a better propulsive effect from the oars.  The trouble was it was taking too much time and I wanted to get back to the steamer so the rowing boat is on the back burner again.

[Circlip]

  'Tony thing thall cut wi blunt twoills is thisen and keep thi fingers at back ont edge.' Wise words from
   my various mentors as an apprentice - a proper one, not todays mamby pambies. It's surprising how
   many of todays tradesmen dont know how to sharpen tools, something we were taught as 12 year
   olds at school. Spose it's the throwaway society again but to reiterate, good quality sharp tools. if
   you go to car boots look for rusty OLD wood chisels, they will probably be made from CARBON steel
   and will keep a far better edge than High speed or HSS tools.  I'm the wrong side of 60 but cherish
   some that belonged to my grandfather.

       Another Ian

[tigertiger]

  OLD wood chisels, they will probably be made from CARBON steel
   and will keep a far better edge than High speed or HSS tools.

I used to work in a butchers and the 'old' knives that went rusty if neglected were much easier to sharpen. They went blunt quicker but my god you cvould make em razor sharp. when the food hygiene regs made it so that we had to use stainless steel, one the factory edge was gone, you could not put it back.

[Circlip]

     I keep trying to sharpen SS knives with diamond laps but not much success, although I don't have
     any problems with 'Old' knives,chisels etc - must be an age thing. I think they must use 'Chemical sharpening'
     techniques, like some scalpel blades are done. I trust that everyone who uses modelling knives has a
     diamond 'stone', providing you don't put too much weight on trying to cut the wood/plastic and break
     them these blades can last a rediculously long time.

[tigertiger]

Surgical steel is really designed to hold an edge and be hygienic, but is not suitalbe for being sharpened. e.g. scalpel blades. When it crossed over to butcher/kitchen knives the material is not best suited.


Back to the topic though, I like the idea of the packing cases above, and any other small 'projects' to hone the skills on.
Any other suggestions?
I am looking at a small Grand Banks Dory for Mary J Ward.

[Voyager]

That's very impressive looking model you have there Bunkerbarge I wish i was good working with wood, nothing i do with wood looks that good!?

[Bunkerbarge]

I'm afraid I can't claim credit for the rowing boat.  The hull was an Ebay find, all I've done to it was add the floor boards, the packing cases, sealed and painted the outsides and given the insides a coat of varnish.

The exercise for me was to make a working rowing boat which is going quite well but, as always taking up a lot of time.  I'm actually very pleased with the way it's going though.  Too many projects, too little time!!

[chas]

I've had or still have many of the problems that everyone else has, but one thing especially drives me mad. When I cut plasticard with a steel rule and Stanley knife, the rule can slip so easily, and being a good yorkshireman I hate wasting the stuff. Has anyone got a fix for this, or perhaps know of a non-slip steel rule?
 Chas

[Bunkerbarge]

Fiskars do a flexible steel rule with a cork backing.  Youn could also glue something like rubber jointing to the back of a rule or, what is probably the most effective do not press too hard when you are making the initial cuts.

I always drag the knife a number of times starting off with little pressure and building up as the cut deepens.  Plasticard doesn't even need to be cut very deeply before it will fold and break neatly along your cut so you don't need a lot of pressure at any time.

[chas]

Thanks for the info, I have a poorly left hand so holding the rule still can be a problem, I try not to press on too hard with the knife, but this seems to be my blind spot.
   I just clicked on to fiskars and was greeted with the yoga for crafters logo, perhaps that is the answer! Meditate, cut, glue. Solves all problems. It might help next time I try a steering course too, I couldn't be any worse.
 Chas

[Bunkerbarge]

I am not sure where you would look for it but on cargo ships we always had a supply of a rubberised paper for putting on surfaces to prevent things sliding around in bad weather.  It was actually very sticky to the touch and you would always use a sheet of it to line your cabin shelves etc and use it for putting your glass on in the bar.

I haven't seen it for many years but you might get it from chandlers or yacht suppliers etc.  It used to come in a roll and you would simply cut off what you wanted.  Something of that nature, glued to the back of your rule would work perfectly as there is no way the rule would move sideways once it was placed down.

[DickyD]

I've had or still have many of the problems that everyone else has, but one thing especially drives me mad. When I cut plasticard with a steel rule and Stanley knife, the rule can slip so easily, and being a good yorkshireman I hate wasting the stuff. Has anyone got a fix for this, or perhaps know of a non-slip steel rule?
 Chas

Impex make a 40cm stainless rule with a rubber insert to stop slipping. I have one and it is excellent. I obtained it at Hobbycraft.

http://www.impexcreativecrafts.co.uk/jpgs/2006/page74.jpg

[chas]

Thanks guys, that rule from inpex looks just the job for me. There's nothing to beat a recommendation from another modeler. I won't be able to blame the beer next time it goes wrong though.
chas

[tigertiger]

Hi Chas

I have just had another thought. If your poorly hand is preventing adding adding enough pressure, then the plastic may also slip on the cutting board. If this is the case then yu could use a rubber mat to cut on. If you only score the plasticard (then bend) and not cut thorugh all the way then the rubber mat will not be damaged.

[chas]

Hi,
  You're right, I've got a cutting mat and wouldn't be without it. I'll keep practising with the plastic.
   I've been cutting wood for years, and tend to cut plastic as though it is wood. It's all part of the fun in this hobby, learning new skills.
   Back to the original question, I find that sanding down to the line can give  a curve to a straight line, for a straight line a good clean cut works for me. If it's thicker ply, I score with a stanley first, and follow with a saw. Put the cut on the face side and you get a cleaner edge.
 Chas

[DickyD]

If you want a nice clean edge when cutting ply apply masking tape to the face side where you want to cut and mark out on it and cut through it. This works with laminates as well. 

[Bee]

Marking the wood to be cut.
Carpenters use a pencil (those oval ones so they don't roll off thebench)
Joiners use a knife - it makes a very thin line. And not an ordinary knife where the metal is ground on both sides but more like a chisel, only one side is bevelled so that the flat side goes right up against the rule.

Cutting a piece of wood to length.
After marking the exact length with your knife against the set square take a nice wide bevel edged chisel and place its super sharp blade into the cut with the bevel towards the waste. Push or tap to deepen the cut to 1-3 mm depending on whether you are working on sticks or logs. From the waste side chisel in towards the cut at 45 degrees to make a groove with one side vertical dead to length and one side at an angle. (actually you make this in stages rather than going down the full depth in one go) repeat on all 4 sides.
Now you can drop your saw into this groove and it will cut right on target. The crucial outer edges are clean knife cuts, not as torn by the saw.

Sharp teeth.
Actually a saw is more precise with blunt teeth! Sharp teeth dig in deeper and unless the tooth angle is very low will not slice but tear the wood. When the point of each tooth is worn off a bit  it actually tears less.
A saw without any tooth set is also prefferable for small work where the depth is low making clearance unnecessary.