Forum sponsored by:

Miniature welding

Search for: in Thread Title in

Paul Boscott	08/01/2011 08:31:47
99 forum posts 21 photos	To more accurately represent the machine I am trying to model I would like to be able to electric weld some of the steel parts together. In particular a fillet of 1.5 mm when joining a piece of 1mm sheet to a 4mm plate. Has any one any experience achieving this.
JasonB	08/01/2011 09:15:17
25215 forum posts 3105 photos 1 articles	I've seen thinner plate tig welded together with very small fillets. The other option would be to do as the armour modelers do and use either an epoxy or liquid plastic to form dummy weld seams thats assuming its all going to be painted. J
Nicholas Farr	08/01/2011 10:51:39
3988 forum posts 1799 photos	Hi Paul, it will depend on your welding skills. I'm not sure that I could achive it myself as most of the welding I've done has been on 6mm plate upwards, and I think I'd need a little more dexterity than I have got now. The problem you have is being able to get enough heat into the 4mm while not over heating the 1mm. As the 4 mm will tend to chill the weld quickly, preheating the whole job, even if it is only 60 to 100 degrees with a hot air gun will help. As Jason says TIG is one way of possible achievment. Regards Nick.
Howard Jones	08/01/2011 11:03:47
70 forum posts 112 photos	the results are quite variable, quite problematic, but you can arc weld these sizes. 2 mm welding rod, around 60 amps or less on the electrode and an angled rod if the metals are perfectly clean. you'd need a fairly practised hand. however a damp rod, slightest hint of oil on the surfaces and you will go insane. as the guys suggest Tig is a gentler weld. ask whaterver the PFA have become for the name of a nearby aircraft welder if you or a friend cant do it.
Terryd	08/01/2011 11:11:19
1946 forum posts 179 photos	Hi There, Why not soft solder? That will create a small fillet, or silver solder and create a fillet with a filler such as Milliput. Once painted it will look authentic. In my experience you will have a problem creating a small fillet with welding, even with tig. Aside from the difficulties already mentioned it doesn't scale down. Regards Terry
Chris Trice	08/01/2011 11:39:24
1376 forum posts 10 photos	I don't think the fillet he's after looks like the smooth fillet you get from either soft or silver solder. Welding only produces a molten pool in a tiny area at a time and the finish is more akin to oil paint applied with a pallet knife or squirted straight out of the tube. Is the model functional and/or likely to get hot or is it purely for show? Artists tube acrylic paint squirted through a syringe is good for faking weld seams in miniature but obviously the scale of the model dictates the application method.
Ian S C	08/01/2011 11:48:04
7468 forum posts 230 photos	An uncle of dads, worked at Bletchly Park during WW2, he told me that for making valves (radio) for the computor the welded them using darning needles. Apparently they went all over that part of the country, buying every needle they could find. I think they used batteries as a power source, don't no the voltage. I have had some very thin (.007")stainless TIG welded, it requires minimum power on the welder, and a sharp point ground on the tip of the electrodes, also a steady hand. Ian S C
Terryd	08/01/2011 12:21:47
1946 forum posts 179 photos	Hi Chris, I have considerable experience of MMA, MIG and gas (oxyacetylene) welding (I began with MMA during my apprenticeship in the early '60s) and although not particularly highly skilled I can produce welds with very small ripple which would be almost unnoticeable when scaled down to the extent Paul intends. I have welded 20 gauge (0.91mm) sheet using MMA with 16g rods but was unable to produce anything smaller than a 4mm fillet in order to achieve decent weld penetration. Also I doubt if welding materials such as 1mm to 4mm ms would be possible with needles as there would not be enough heat generation to penetrate the thicker materials. You don't get material that thick in a thermionic valve. It is possible to weld materials of dissimilar thickness by aiming the heat source accurately so that it is directed more at the thicker material, the angle depending on the actual thicknesses, but it takes quite a bit of practice to be successful. Hi Paul, What scale are you working to as that will affect the welding method for example down to 1/4 scale the weld ripple may be noticeable but at 1/10th it would not be discernible, especially if the original was painted. Also are the materials to be fillet welded at say 90 degrees or are they to be butt welded flat? This would affect the method used. Best regards Terry
John Stevenson	08/01/2011 12:52:05
5068 forum posts 3 photos	Perfectly doable with TiG, It sounds a big difference but 1 mm to 4mm isn't that far out. One point to take into account is the advances made in recent years with welding products as they have moved from the older transformer based machines onto inverter based machines with oddles of electronics inside, square wave, pulse, arc boost, ear of bat etc. Unless you have used the latest machines you just can't compare, as an example I have a 12 year old TransTIG 200 amp machine here, bought new and never put away wet. I could weld that 1mm to 4mm but it would have a pronounced fillet. I recently invested in an inverter 200 amp machine and using this is like night and day compared to the Transtig to the point the transtig is there only as a backup machine. A while ago the body shop across the road came in with a flexible pipe assembly, alloy block with two alloy pipes coming off then went into flex pipes, then back to alloy and onto two separate blocks. This was off an air-con pump of one of their curtsey cars that had had a bump. A new pipe assembly was part of the pump and was £800 and they would have to stand this. One alloy pipe was broken clean off on a 90 decree bend and could I weld it back? Pipe was 13mm diameter and 30 thou thick, seeing as it was scrap I couldn't do anymore damage and they accepted this. Played on a bit of scrap sheet to get settings and set the TiG to 22 amps and welded this pipe all the way round, not very neat but I was frightened of allowing it to collapse and close the hole up. No way could the Transtig have done this. John S.
Nicholas Farr	08/01/2011 13:12:23
3988 forum posts 1799 photos	Hi Terry, oxy-acetylene, I used to like that method, and still do now and again. My advanced gas welding exam was a 60 degree 1-1/2" into a 3" pipe stab with about a 4mm wall thickness, in the overhead position, on a red hot summers day, phew! It was set up by the examaner and you were not allowed to move it at all. Although it has a high heat input into the whole job, I've always found it the most controlable weld method. Of course one of the disadvantages is a large amount of distortion on thin metal, due to heating of the HAZ (heat affected zone) being broad, compared to electric arc methods. This can be overcome in a lot of cases by keeping the heat input as low as possible and peening the weld afterwards though. Regards Nick.
JasonB	08/01/2011 13:20:12
25215 forum posts 3105 photos 1 articles	Its surprising how small the weld will still be visible, as I said the Armour modelers add weld detail and this is typically on 1/35th scale models, granted they were big weld seams but pauls structure is quite a size as well. I Think I would join the parts with silver or soft solder as Terry said and then add the weld detail afterwards, that way you can get a good structural joint first and then worry about what it looks like later. The small weld seamd that I said I'd seen were done with a modern TIG welder as JS mentions, wish my welding was as good Jason Edited By JasonB on 08/01/2011 13:22:15
John Stevenson	08/01/2011 13:35:08
5068 forum posts 3 photos	You can always bodge it !! I think enough time has gone by now for the statute of limitations to run out Years ago we were responsible for preparing HGV's for annual test and for many it was the first test they had ever had and believe me they needed one. One particular bad vehicle was the Dodge D308, this had a double and triple skinned cab in places and rotted like crazy but because the main bearers were sound it was still safe. It's just the testers didn't like to see rat holes in the sheet work, problem was welding to one side was OK but nothing to weld to on the other side. I spent literally hours on these chasing cob webs. So one day I cut a piece of plate and hammered it to shape to fit nicely, then put the plate in the vise and ran a perfect bead of weld along two edges, this was then welded in and blacked over. At test the examiner commented he's never seen a nicer piece of welding and passed it. John S.
Nicholas Farr	08/01/2011 16:15:31
3988 forum posts 1799 photos	Hi John, call that a bodge! In the seventies we used to have to patch up plant where 6mm plate had been worn paper thin in the middle of panels, so you would weld where you could and then finish with putty. By the late eighties onwards and with the more popular use of silicone sealent, well !! we didn't even bother with the welder, and often the patch was rubber if it wasn't a hot zone. Looks and testing wasn't an issue though, just had to keep the product in, untill the next major maintenance shutdown. Regards Nick. Edited By Nicholas Farr on 08/01/2011 16:33:20
Ian Abbott	08/01/2011 20:24:59
279 forum posts 21 photos	At one time, I quite often had to weld dissimilar thicknesses, with one edge down to about 1/16". Like Terryd, I would heat only the thicker piece, with a tiny flame. When I had a puddle, I'd let it come up to the thin edge, then carefully run the bead just beside the joint and let the puddle do the welding. Often the job would be on a machine, so there was no way of using firebrick to help keep the heat even. Patience, patience, patience..... We'd do something similar with solder repairs. Heat an area away from a soldered joint and then nudge the flame towards the joint, just enough to let the solder run, then backing away, keeping the heat just below the melting point. Quick nudge would allow a series of additions, then a pass over to smooth the joint. Ian
Dave Tointon	09/01/2011 03:06:17
49 forum posts	G'Day All, Talking of bodges, heard this story from an Aircraft Engineer in New Guinea. Some of the lads were working on an early model Pilatus aircraft with a pusher prop. Finally in the early hours of the morning, they test ran the aeroplane, however unfortunately someone had left a big spanner sitting on the wing which went through the prop. A spare prop wasn.t held in stores and was unlikely to be available anywhere in the region. Nevertheless, the aeroplane was back on the line in time for it's scheduled run later in the morning. It was a few months later when the prop went in for overhaul that the sh@# really hit the fan. Frantic correspondence came from the horified overhauler that one of the blades had a large dint, had been stop drilled , automotive body filler applied, filed up and had been painted over. Consensus was that the engineer concerned was a good bloke and that his judgement was sound as the prop had run to its full service life without coming to bits!!! Regards Dave Tointon
Paul Boscott	09/01/2011 05:50:12
99 forum posts 21 photos	Thank you for all of your contributions BUT I would like to get this thread back on to its original question I would like to know before I spend to £200 to £300 on equipment if it is possible assuming that I acquire the necessary skill to produce a miniature weld that would any where near replicate at 1/12 scale the type of construction the that in real engineering practice makes a component / structure by seam welding 2 - 3 inch steel plates together?
JasonB	09/01/2011 08:11:48
25215 forum posts 3105 photos 1 articles	The welders I have seen doing the small fillets are nearer the £1000+ mark and thats for a small one that will work of a 13amp socket, as John said you need the controls and gizmos like HF start, slope up, slope down, pulse, etc The arc/tig welders from machine mart with the additional tig kit are just not upto it or any touch tig for that matter. The other problem you will have is that your 1.5mm 1/12th scale weld will have been run as several runs as you cannot do an 18mm weld in one pass so you would at best have to run something like 3 or 4 0.5mm beads of weld. Jason Edited By JasonB on 09/01/2011 08:13:20
Terryd	09/01/2011 10:52:30
1946 forum posts 179 photos	Paul, From reading all the previous posts (not the OT ones) I think that your question has already been answered and that answer is "unlikely". I would not fancy even attempting it, but I have only 50 years experience. As I said, welding doesn't scale, even with the best equipment, the ripples of the weld will still be 12" to the foot scale. Regards Terry
John Stevenson	09/01/2011 11:19:20
5068 forum posts 3 photos	Is that 50 years experience using the latest equipment ?? As I said earlier unless you are familiar with the equipment that has been released in the last 2 to 3 years than all this 'experience' will not really count and that also includes my experience. I can weld things today I could not weld last year, simple statement. I can't match 50 years experience, only been welding for 47 but in all fairness that is not 47 years solid welding however as a guide out of two bottles of gas on rental, Argon and Argon mix, I need about 10 refills a year. I no longer do enough gas welding to warrant a set of bottles and they were handed back about 5 years ago. I was looking at some titanium pipes the other day that had been welded to a 6mm flange, the pipes wire about 16mm and the welding was exquisite, tiny, tiny horseshoes of perfect weld, probably as many as 50 around one pipe. John S.
Terryd	09/01/2011 11:42:44
1946 forum posts 179 photos	Hi John, i don't think 50 years would be possible with the 'latest equipment' would it? I don't have a time machine. I only managed a couple of months with it before I retired last year. I think that the welding Paul requires is possible but doesn't scale down to 1/12. I did say the process was 'unlikely' to be successful with the sort of equipment Paul was suggesting with obviously little or no previous welding experience. Even with the 'latest equipment' welding is still a highly skilled process not easily picked up without skilled tuition. As a 'Jack of All Trades' I was never highly skilled but could turn out welds good enough for structural steelwork etc with any of the methods mentioned earlier. However I used to marvel at the guys who were welding the large pressure vessels we used to turn out for use in the nuclear reactors of the power industry. I now only average a couple of bottles of 'Argoshield' a year in my home workshop. Regards Terry

1 2 3 Next > Last >>

All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

You can unsubscribe at anytime. View our privacy policy at www.mortons.co.uk/privacy

Latest Forum Posts

*Oct 2023: FORUM MIGRATION TIMELINE*
05/10/2023 07:57:11
Making ER11 collet chuck
05/10/2023 07:56:24
What did you do today? 2023
05/10/2023 07:25:01
Orrery
05/10/2023 06:00:41
Wera hand-tools
05/10/2023 05:47:07
New member
05/10/2023 04:40:11
Problems with external pot on at1 vfd
05/10/2023 00:06:32
Drain plug
04/10/2023 23:36:17
digi phase converter for 10 machines.....
04/10/2023 23:13:48
Winter Storage Of Locomotives
04/10/2023 21:02:11
More Latest Posts...
View All Topics

Support Our Partners

Shopping Partners

Subscription Offer

Latest "For Sale" Ads

Reeves** - Rebuilt Royal Scot by Martin Evans
by John Broughton
£300.00
BRITANNIA 5" GAUGE James Perrier
by Jon Seabright 1
£2,500.00
Drill Grinder - for restoration
by Nigel Graham 2
£0.00
WARCO WM18 MILLING MACHINE
by Alex Chudley
£1,200.00
MYFORD SUPER 7 LATHE
by Alex Chudley
£2,000.00
More "For Sale" Ads...

Latest "Wanted" Ads

D1-3 backplate
by Michael Horley
Price Not Specified
fixed steady for a Colchester bantam mark1 800
by George Jervis
Price Not Specified
lbsc pansy
by JACK SIDEBOTHAM
Price Not Specified
Pratt Burnerd multifit chuck key.
by Tim Riome
Price Not Specified
BANDSAW BLADE WELDER
by HUGH
Price Not Specified
More "Wanted" Ads...

Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues