Sheet metal folder

[Roger]

I had to slightly reduce the depth of the blocks so that they fitted in the RHS tube less tightly.

Here are the adjusters which ended up not being long enough so I switched to threaded rod.

20160517_092333 by Roger Froud, on Flickr

There are just a pair of nuts locked together inside, and that's enough to move the block.

20160517_101019 by Roger Froud, on Flickr

The extensions were chamfered at 45 degrees and brought almost to a sharp edge for welding.

20160517_130119 by Roger Froud, on Flickr

Two tacks on each side first.

20160517_130552 by Roger Froud, on Flickr

Don't look too closely, I know that's not great. It does penetrate right to the middle though, I could see it melt to the bottom.


20160517_131649 by Roger Froud, on Flickr



20160517_133840 by Roger Froud, on Flickr



20160517_134327 by Roger Froud, on Flickr

That one looks a bit better. I could have used more filler rod but I thought it was better to leave it nearly flush since it all has to end up that way.

20160517_134822 by Roger Froud, on Flickr



20160517_140339 by Roger Froud, on Flickr

This is the flat going on the underside of the clamping angle.


20160517_172105 by Roger Froud, on Flickr

So far so good, it all seems to fit.

20160517_180147 by Roger Froud, on Flickr

I decided to make some 25mm thick walled tube from solid bar and weld them on for the handles. I'm coming to the conclusion that many of my welding problems stem from not having a steady hand. I've clamped a piece of material onto this setup to rest my hand on and that helped a lot.

20160517_205442 by Roger Froud, on Flickr

and the same on this side.

20160517_210651 by Roger Froud, on Flickr

with the solid 20mm diameter bars 400mm long for handles. I might make a thumbscrew to hold those in place. I want them removable so it can be stowed away more easily.

20160517_221538 by Roger Froud, on Flickr

[KennLindeman]

Morning Roger. Looking good. What's the secret to being able to get so much work shop time or do you work between 12 midnight and 6 in the morning. I normally only get between 8 & 10 in the evening after the kids are in bed, but now the winter is creeping in here in Cape Town and the mind and body is getting weak. Thanks for the photos and progress reports

[Roger]

Hi Ken,
I don't need to work full time to live, so that gives me more time. Fortunately my Wife is very understanding and doesn't make too many demands on my time. We don't share many common interests so we do our own thing. My kids are grown up so I don't have that commitment any more either. I reckon to spend at between 4-6 hours a day on average on something related to 1501 so I get a lot done.
It's hard to stay focused sometimes, but I keep ploughing on else I know it will never get finished.

I've also spent a lot of time improving my workshop and equipment so that I'm as productive as possible.

[Roger]

These are the clearance slots for the M8 clamping bolts going in.



20160518_095149 by Roger Froud, on Flickr

The first full assembly showed up a few issues. The folding arm wouldn't go quite flat against the RHS base, so the backs of the hinges had 0.3mm trimmed off the backs to make sure it would. With hindsight, it would have been better to have mounted the base plate 0.5mm further forward on the RHS and adjust everything else to suit to there would be more clearance.

It's also very clear from tightening down on a test piece in the middle of the bar, that the clamping angle is much too flexible. I'll add that triangulation piece I described earlier before doing anything else.

20160518_110620 by Roger Froud, on Flickr

[Roger]

This is what I'm doing to apply a pressure point in the middle of the clamp arm. The support rods are 16mm diameter so they're pretty massive. The jacking point has an M10 thread and there will be a shaped piece over the back of the angle for it to bear on.


Clamping arm assembly by Roger Froud, on Flickr

Obviously there are ways of making the curved and Vee shaped ends using traditional methods, but on balance it was easier to set them up so that they could be done in one operation, guaranteeing that they were correctly orientated to each other.

The cutouts were modelled and containment regions drawn round them to make sure the tool path only created those areas.

This is after the roughing pass with a 5mm ripper leaving 0.3mm to finish in the second pass

20160518_180614 by Roger Froud, on Flickr

The vee was finished with a 2.5mm 2-flute and the rounded end with a 10mm 2-flute. These days I'm using ball nosed cutters less and less because I can get a good enough finish for my purposes with conventional cutters. The software has options for all kinds of cutter styles, you just select the type you want to use.


20160518_193720 by Roger Froud, on Flickr

It's going to get welded on, so there's no point in making a better job  of it than this.

20160518_193736 by Roger Froud, on Flickr

A small flat was added to the corner of the angle because the Vee has a 2.5mm flat from using a 2.5mm 2-flute.
It fits really snugly which will make setting it up for welding easier as well as making the weld itself easier.

20160518_200136 by Roger Froud, on Flickr

The TIG welder has opened up a new avenue of solutions that I haven't been using to date. Although I occasionally had things welded by my dear friend Bill, I always used it as a last resort.

[Roger]

I was stuck with a customer until gone seven tonight, so this didn't quite get finished. It's probably just as well, because it was so hot, I couldn't rest on any of it to support my hand.

I supported one strut on a Vee block and clamped the central boss onto a large parallel then set the angle with a vernier protractor to tack it. Same for the other arm.

The tricky bit was tacking the two arms to the angle. In the end, I held it with one hand and melted a tack without filler wire. That worked so well that I didn't use any filler wire for the tacks unless the puddles wouldn't bridge the gap. It makes for a neater joint if you don't have to pass a big blobby tack.

20160519_220555 by Roger Froud, on Flickr


Anyway, here are the four main welds on the angle. I'm pretty sure they're strong, it looked like it was nicely melting down to the root of the joint. It certainly took a lot of current though, 170Amp pulses reducing to 60Amps for 33% of the time. I've been experimenting with the start current too, and settled on 60Amps with the pedal just pressed. I think that could be raised a bit to get even more feel on the pedal.

Lots still to learn. The main thing for me is to be able to rest my hand and be able to swivel my wrist to reach the length of weld I'm attempting. 

So here's what the ends look like, not the prettiest job, but not a complete embarrassment either.


20160519_223843 by Roger Froud, on Flickr

I probably don't need to do the ends, this looks plenty strong enough to me.

20160519_223913 by Roger Froud, on Flickr



20160519_223918 by Roger Froud, on Flickr


20160519_223837 by Roger Froud, on Flickr

This is the pressure pad that the M10 bolt will drop into when it's resting on the back of the angle. There will be a recess in the back for the threaded rod to stop it from tipping over.

20160519_224039 by Roger Froud, on Flickr

[Roger]

I'm really pleased with my crude welding table, it's easy to support the work at various angles and provides support for my wrist.
The glove is to stop me from burning my wrist while welding that top joint.

20160520_101536 by Roger Froud, on Flickr

Ok, I could use some advice on how to finish the run when TIG welding, because that's what's leaving those nasty lumps. I've been tapering off the power, and even going back on the weld path a little, but I'm still getting it sometimes. The weld itself is reasonably neat except for that.
Any ideas?

20160520_102155 by Roger Froud, on Flickr

[jem]

Hi Roger,

I have been welding stick , gas and a little mig, for many years as an amatur and I must say for the short time you have been welding, those welds are really good and neat, I certainly cannot guarantee that quality every time! however a disk grinder works very well for hiding bad bits. I have never had a gop at tig, but it certainly looks very interesting, so maybe I should look into it. Which welder did you buy please. You seem to perform some very big welds , I always thought tig was just for very fine welding.

I bought a head mask with a self darkening window not expensive, and I find that it makes life so much easier, having 2 hands free.

all the best with your welding

Jem

[Doug]

Love the welds, made me go and set up my little tig unit at work (cheap chinese plasma/tig unit) it worked surprisingly well but not very delicate, we also have a "proper" aerospace calibrated one on site which is awsome but I don't like playing with it as I have a tendency to melt the electrodes or get steel on it then I have to go and get it reground.

in awe of your natural skill looks like you have been welding for years 

[Roger]

Hi Jem and Doug,
Trust me, I have no natural talent for welding, I've always struggled in the past. Part of that is because I couldn't see what was going on, and the other was not having a steady hand. The welder I bought is this one and I couldn't be more impressed. It's an AC/DC unit so it can weld Aluminium as well as Steels. It takes a bit of getting your head round what the control settings do and why they're there, but once you've cracked that, you can get it to do whatever you need.

On the Superheaters, I was working without my glasses and getting up very close to see what I was doing. That works, but it's a pain because I'm blind as a bat unless I'm up really close, and that makes it hard to get the filler rod in there because my head's in the way. This bigger stuff has been done using a 2.5 Diopter  'cheater lens' so it looks much bigger and I can keep my glasses on. I've ordered a 3.5 Diopter lens in the hope that it will let me do even the small stuff with my glasses on. Watch this space.

What I really like about TIG is that the position of the electrode doesn't change, ie it's not consumable and it doesn't squirt out of the nozzle like it does with MIG. I find it's much easier to be precise so long as you can see what you're doing and rest your hand comfortably. Watching loads of YouTube videos helped a lot, particularly seeing that they sometimes do several dummy runs along the length of the weld to make sure that they can track the torch comfortably along that line. That's the key for me. I'm getting a little bolder now I know what it needs to look like with a puddle forming on both parts of the joint, usually joining before adding filler rod. The welder I bought is very responsive on the pedal and you can wind up the power if it isn't melting and back off if it's all getting a bit lively. I don't think I'll ever be that good at it, but with kit like this, it's surprising what a novice can achieve.

[Roger]

I made the adjuster blocks for the folder arm today, just a simple 'part on a stick' 15mm deep and the holes added then parted off.

I know some people are wary of intermittent cuts, but if the lathe is rigid enough, you can do it like this under power without any drama. This is my trusty parting and grooving tool. A quick clean up with a file and that's a simple job done. You can see one fitted on the next but one picture, it's got a long M5 grub screw through it.

It became quickly clear that setting up the folder for a bend needed a bit of thought. Normally, the height of the pivot is fixed, but on my design it's adjustable. After a bit of experimentation, I found that the easiest way to do this was to set the folding arm to a 90 degree bend first, and set the outer radius of the bend as the gap you can see daylight through in this picture.

That's easy to say, and not easy to do, so this is what I've made  tonight. The block on the end has a button on the end that can be slid under the arm to hold it exactly at 90 degrees as you can see by the square. The gap can then be set with feeler or Slip gauges which are held against the vertical face and slid down into the gap.

Once the gap is set, the folding arm is dropped down, and the height of the pivot point set so that the folding angle is exactly level with the table. A straight edge can be used to check this.

20160520_233112 by Roger Froud, on Flickr

This is what it looks like underneath.

20160520_233135 by Roger Froud, on Flickr

The start of the bend is set exactly on the edge of the table, this is one of the drain cock mechanism brackets being folded.

20160520_160909 by Roger Froud, on Flickr

They came out really well so I'm pleased with those.

20160520_233222 by Roger Froud, on Flickr


I also added a groove to the ends of the folding arms and M5 threads to the support tubes so they can be slotted in and engaged with the thread to stop them falling out.

20160520_233346 by Roger Froud, on Flickr

I've ordered two springs to go under the ends of the clamping angle so that it's easier to set the job.

Hopefully that's all I need to do on this and I can fold the drain cock lugs and move on.


Actually, scratch that, I think it would be really handy to add a couple of dowels to the clamping arm so that it guarantees the lineup of that to the front of the table. It would also stop the clamping bar from sliding back when the fold is being done if the clamping force isn't sufficient.

[Roger]

I've been looking at the weldingtipsandtricks YouTube channel for a while now, and Jody on there is such a good teacher.
I thought I'd share this video with you because it has some really neat tools to hold work and some clever techniques for very quick tacking of parts, almost like spot welding. It produces tiny tacks in a fraction of a second and it's something I think I'll try.

[Roger]

Here's that modification I mentioned yesterday, just a pair of 5mm reamed holes going in on the back of the clamping bar and through the base plate.

It's not ideal really because the top will distort when it's clamped down slightly and the front edge might be slightly out. In reality, it's a lot better than having it floating so we'll have to see how it works.

20160521_103554 by Roger Froud, on Flickr

So this is the way to set it up. The material thickness doesn't come into the equation at all, all I'm interested in is the outside radius of the bend.

In this case it's 0.7mm thick material, but the outside radius is 1.05mm as taken from the 3D model. What's handy is that the sheet metal CAD package allows you to define the bend line and then it applies the rules that you've chosen for that gauge of material Then you can just read off the outside radius it creates.

Here the stop has been slid into place that holds the folding angle at 90 degrees. I'm sliding a 1.05mm slip gauge into the gap and adjusting both ends so it just slides in. The clamp screws hold the bar in place, but there's the backup of the adjusting screw in case it slips.

20160521_112636 by Roger Froud, on Flickr

With it dropped back down, the same slip can be used to check that the table base and the folding arm are dead level. To be honest, you can feel it just as well by running a finger back and forth over the join. The adjusting screw on the bottom is moving the whole end plate up or down to get this right.

20160521_112927 by Roger Froud, on Flickr

The front of the folding arm turns out to be a handy reference edge to set up the part, in this case the part showing is set round at 30 degrees. You can see the alignment dowel for the clamping bar with a knurled top behind the clamping screw.

20160521_122329 by Roger Froud, on Flickr

And here is the result, three of each hand of the little lugs that operate the drain cocks.

20160521_123031 by Roger Froud, on Flickr

I really don't understand why commercial machines don't have a moveable pivot point, it's simple enough to do. I suppose if the machine range is limited to say 1.6mm material and you can move down the folding bar, you can create different bends, but it's a bit of a bodge in the geometry department.


Anyway, so far so good. I'm of the opinion that the folding angle is going to need the same treatment as the clamping bar ie some sort of triangulation  may be needed to stiffen up the bar. For the time being, I've folded the things that prompted me to make it, so I'll leave it at that for the moment.

[ivattlms]

Hi Roger are you finished making the folder and are you happy with it Robert

[Roger]

Hi Robert,
I'm pretty happy with it, although I've not really tested it up to its full capacity as yet. It certainly works well with what I've tested it with so far. Like everything, there are things that could be improved and I'll mention those when I make the drawings available.