Fuselage building jigs

[trebor]

Can anyone tell me if there are any different ones to Slec jigs about in the UK. Is there anyone else making them ? Tried doing a search but most are in the US.

[Cuban8]

I still use my jig bought from South Yorks Model Supplies years ago. To be honest you could get the materials from B&Q and make something similar for only a few quid and an afternoon's work.

The base is just contiboard that I resurfaced with cork so I can use it as a building board, there's a couple of lengths of 2X1 screwed to the underside to keep it true. Extra holes have been drilled in it allow for larger models - the one in the pic is my 1/3 Turbulent. I suppose the awkward bit would be to make the adjustable side fences, but depending on what tools and carpentry skills one has, shouldn't be too bad.

Maybe SLEC do their's as spares?

 

 

Edited By Cuban8 on 22/01/2015 17:54:00

[trebor]

I have thought about it but I'm limited to wood tools, I don't have anything that would cut slots. Suppose I could make slotted thin boxes for the clamps but would have to make everything by hand and I know it would turn out better cut with a machine.

[kc]

Slots could be builtup......A centre piece of 1/4 inch between two pieces of 1/2 inch square would create a slot suitable for a M6 bolt. Make up a long length with the 1/4 spacers and cut off into individual clamp lengths ( save fiddly gluing work if you make 1 spacer for 2 angles and cut between )

But you can buy spare SLEC angle bits

[trebor]

I feel a plan coming together, the centre piece could be hard wood sandwiched with ply sides with a long bolt through. If only I had a table circular saw

[kc]

Go to B&Q or others where they have a panel saw, buy a sheet of ply and get them to cut a strip off and then slice it into the size you need. You get about 3 cuts free. A smaller timberyard might also be persuaded to cut the size you need on a table saw. Otherwise cut by hand on one of those mitre saws with a guided saw blade. ( magic gadgets - you will use it all the time! buy one with a wide cut)

But high precision is not needed, if you screw the triangles ( or squares) to the slotted base there is some chance of adjustment -put the glue on, then 1 screw and adjust. When glue is dry put in the second screw for a solid job.

[kc]

This is a photo of my crudely made jig which has been in use for about 30 years.

The slotted parts were made by drilling holes each end and cutting between with a coping saw ( laminating would be easier!) Uprights are offcuts and base is melamine coated chipboard which allows pencil lines for former posiitions to be drawn and then erased. Centre line is scored. Bolts are steel - dont bother trying nylon wing bolts they just stretch and never tighten enough. Roofing bolts are cheap and have a large head.  Alternatively use these dowel bolts and tighten with an allen key.  Large ( 'penny' ) washers are needed. 

In this case the bolts go into captive nuts but proper M6 threaded inserts from Screwfix would be better - they screw in with an allen key. Otherwise ordinary hexagon nuts can be drawn in with a bolt and washer if you counterbore a hole the same diameter as the distance across flats. For M6 this is 10mm. The 'corners' of the hexagons cut their own way into most wood and dont spin.

Note the front pair in photo they show that as the uprights are offset they can be swopped with the opposite side which moves the upright about 2 inches along the base which is handy and minimises the number of holes needed.

In use the uprights are set on to the unglued fuselage for a trial assembly and pushed from either side until centre of formers line up on centreline.  Then all the uprights along one side only are loosened so the fuselage can be removed and glue applied.  Then it's easy just to tighten all one side until centres line up.

 

 

Edited By kc on 23/01/2015 16:12:33

[trebor]

Thanks for the replies, I did find out about b&q free cutting. The main branch will do 15 cuts for free near me so I'm in the planning stage now. What size would be a good average for vertical 90deg brackets ?

[kc]

Depends what size model you build! My models are mainly 25 to 40 size engines, 48 to 60 inch span. The jig would be OK for up to .60 size models too. They dont have to reach the very top of fuselage.

The verticals in photo are 8 inches high, 4 inch base. 18mm MDF or ply would be fine, mine are 16mm melamine chipboard which is not as good to get a nice edge when cut but are OK. They can be rectangular or have corners cut off. Use the machine cut edge as the accurate edge. It would be nice to cover the edge with 1/8 balsa glued on to have a soft surface so not marking fuselage, I use bits of cardboard.

Slotted bits are 20mm square on mine. I suggest laminating using 2 pieces of 10mm by 25mm timber with 6.5mm ply between making a 26.5mm wide by 25mmhigh slotted part.

Note when assembling try to use an engineers square not a woodworkers trysquare which are not accurate on both inside and outside edges ( British Standards are slack on woodworkers standards!)

Base is 36 inch by 14inch from 16mm melamine coated chipboard. Maybe 48 inch long would be better and 16inch wide or maybe 18 inch. Hole spacing is 3.5 inch. Maybe use 3 inch .or 2.5 inch. Maybe 2.5 inch around front end and 3.5 towards tailend. Note that fuselage can overhang the base as usually only the centre part needs gluing first and then can be slid along later when pulling in the tail.

I used 1.5 inch 2BA steel bolts which are OK but M6 are bigger and cheaper, easier to buy. Those dowel bolts seem very cheap at 50 for a couple of quid. Use 35mm bolts so the thickness of the slotted wood and the base itself need to come to 35mm to work nicely. Saves much tedious bolt twiddling if the thread is only just right!  the inserts go into the wood a bit so 35mm might be right, check with your wood.

Edited By kc on 23/01/2015 17:13:23

Edited By kc on 23/01/2015 17:20:02

[trebor]

Do you think if I shaped the vertical bits with a slight radius it would help with the marking on soft balsa ? I have to say I wasn't impressed with the ply at b&q most of it had laminations falling out of the edges and some were well bowed in the 18mm pile.

[kc]

Having checked the actual threaded inserts I have , I reckon they can be put in on the underside of an 18mm base so the top is completely flat. Then making the slotted parts from 10mm by 20mm ( or 10mm by18mm ) they will become 20mm or 18mm high which would suit the 35mm bolts. Bolts won't project but just go into the threaded part enough. Check the actual wood & fittings.

[trebor]

I wonder if wicks do a free cutting service.

[kc]

Certainly round the corners off, but a fairly flat bit will give a greater surface area and reduce the marking. A narrow bit would mark more. I have found a 2inch wide strip of 'cornflake packet' cardboard is enough to stop marking ( the edge of card projects ) Lining with a bit of cork might be OK

MDF is usually dead flat and would make a good base, some ply seems to warp terribly other stuff can be OK. It won't improve whatever you do! Good ply is dear, cheap ply is often poor.

Maybe they have 4 by2ft sheets of ply or MDF small enough to sort through to find a good bit.? Their offcut bin near the saw might produce some decent bits too. It's only the base that needs to be flat, verticals can be softwood or MDF. Try to find a bit of really nice 4inch wide softwood and have it cut into 8 inch lengths ( 10 or a dozen)

[kc]

A few Wickes stores do timber cutting- their catalogue shows Barking, Edmonton, Maidstone, Harlow, Swindon, but most don't -their catalogue says "51 pence per sheet"

Any ordinary timberyard would have a radial arm saw which would chop a 4 inch wide piece of timber into the sort of size you need. The smaller yards might be more helpful especially if you choose a quiet time. But as I said before if you utilise the already machine cut edge as the main edge then any slight errors in hand cutting can be adjusted when you screw it onto the slotted bit. So there should be little problem in cutting it yourself.

[kc]

I have just been out in the garage and made a kingsize version of my magnetic saw guide. This new one is fixed at 90 degrees and uses 4 hatch magnets inset into a piece of 4 by 2 with a batten screwed on at 90 degrees. The magnets ( 10 for a pound at Hobby KIng I think) are put into shallow drilled 10mm holes, and epoxied flush with the surface 2 near the top two lower down. Using an ordinary cheap B &Q 22 inch handsaw this will enable anyone to cut an accurate 90 degrees both ways cut in any piece of timber upto 4 by 2. Try it you will be amazed how you can let the saw run along the surface of the wood and guide it down into the timber.

Or you can buy an adjustable one as a Nobex 505 for 24 pounds -great gadget had one for years- or a Veritas one from 30 to 65 pounds! But a homemade one will work OK.

kc's adjustable small version for modelling..........

[trebor]

Thats a good idea, I can see I'm going to be busy before I start to build anything. I have an old circular saw, might think about making a table to mount that.

[Steve Hargreaves - Moderator]

Why your aversion to just buying the SLEC jig trebor? Much less hassle & they work well in my experience..

[NormB]

Hi trebor, if you've got a portable circular saw then you can easily cut sheet material like MDF or ply.

If the saw's still OK then treat it to a new TCT blade - it'll make all the difference. You can use a guide clamped to the sheet stock and run the saw's sole-plate against it. I don't have room for a table saw so I have to use this method. You'll need some timber strips to support the sheet off the floor; I use 4x2 framing stock from the local builder's merchant (cheap). The guide can be any sheet material you have with a known straight edge and wide enough to allow clamping onto the sheet at it's ends. Lay the sheet onto the support timbers flat on the floor making sure you support both sides if the cut properly. Make a test cut so you can measure how much 'offset' you'll need for positioning your guide. Knowing this amount, set up the guide to give the desired strip / piece width after cutting.

Do a 'dry' run with the blade up so you can get your positioning right and make sure that the sheet's FULLY supported - you'll be kneeling on it! Keep the cable out of the way, over your shoulder's good!

When happy, set the blade depth so that the teeth are just fully out of the material. Start the cut with the blade OUT of the sheet.

Take it slow and be safe.

Here's my jig, I used some surplus birch ply and the hardware from a very old SLEC jig. Base is white Contiboard, holes about 3" pitch along the length, 42" so it fits under the bench when not in use.

The jig parts are built up by laminating bits of ply. The whole thing is multi-purpose and can be used for wing alignment by clamping guides/templates to the 'blades'. Definitely use the screw-in inserts as mentioned in a previous post - brilliant idea, much better than 'prong' type nuts I'd got.

Remember safety first with circular saws. It's not as easy as with a table saw but if you take your time it can be quite accurate.

Fus. is a KK Junior 60 , plan re-drawn from the Outerzone one , electric powered.

Norm

[trebor]

Steve, I know it would be less hassle in the long run but that's me all over. I can see me getting carried away making bits all the time.

Norm, that's is a work of art chap. You thought about producing them ? I'd buy it. I have been looking for some metalwork track so instead of holes to secure clamps you'd have sliding slots but so far I haven't found anything small enough.

[NormB]

The usual alum. track is for general woodwork jig making. Try 'Axminster Tools and Machinery', I use them a lot and have never been disappointed . Thought about the track too but wanted to use the hardware I had - I can be mean . You'll need to rout / saw slots in the baseboard which complicates things a bit as well as having nuts to slide in the slots without jamming ...

T-Track

Producing them - there's an idea.

Norm

[kc]

Circular saws especially with TCT blades tend to kick back which is dangerous. Especially if used in a table which means any kickback is near chest or head level! It's so much safer using hand tools and therefore more satisfying I think. Consider carefully whether expenditure on a picture framing saw ( hand mitre saw) might not be better than a circular saw blade.

Norm's upright construction looks very neat but it has quite a narrow face onto the fuselage which could mark, and of course they are not offset which means you cannot alter the spacing ( by swopping sides) and therefore might need closer hole spacing.

[trebor]

That track looks good, I could screw that to base board build up the thickness and top it off with something hard wearing with slots already cut to allow movement of bolts.

[kc]

The amount of tension needed to hold the uprights firmly is quite considerable and would probably distort aluminium track unless a long slider is used to spread the load. Making wooden slotted parts as Norm or I suggested would be easier or buying SLEC uprights would be cheaper! Tried and trusted ways are best......

[WolstonFlyer]

I just got the SLEC jig, it was delivered a few days ago. A quick trip to B&Q for a length of white faced chipboard and about half an hour putting it together and it's done. They only supply enough captive nuts for half of the number of dots that are marked on the grid sticker, so if you want to drill every marked hole you will have to buy more captive nuts. It would be better if they put the price up a little bit and sent enough.

Edited By WolstonFlyer on 24/01/2015 19:51:16

[NormB]

Just to clarify why I didn't use the SLEC uprights: I bought the jig a very, very long time ago in the vain hope that I might be able to get back into modelling while the kids were still young. Never happened of course!

This was back in the day of geared brushed ferrite motors or Astro / Geist cobalts with NiCds and marginal performance. So the jig was left kicking about in the garage until 2011 when I discovered that the plastic uprights had obviously distorted after all that time and extremes of temperature. I'm sure the new ones are fine, mine must have been OK originally otherwise I wouldn't have kept them.

Norm