F150 6x6 Tow Truck

[Mad Ax 9313]

23 minutes ago, BuggyDad said:

quick question if I may - what sticker base product do you use to put in a laser printer? Looks like you've found a nice balance between not too fragile and not too thick.

I use Glossy Transparent Vinyl and Glossy White Vinyl from Evergreen Products, on Amazon.  Both sheets are fairly thin, although the white does have a tendency to peel off on the roller and jam the printer.  The transparent seems to have the better quality, although large blocks of colour never look right on either paper.  I didn't realise until after I'd unboxed and configured my printer that it's "not compatible with vinyl products" - which is pretty much exclusively what I bought it for, so yet another massive disappointment and a very expensive paperweight in an office full of very expensive paperweights (I've literally never ever used a laser that hasn't printed on vinyl before so I didn't know that not printing on vinyl was even a thing).  Getting a good colour match on the white paper is impossible, something that looks like navy blue on the screen will come out navy blue on regular white printer paper but more like sky blue on the white vinyl.  Generally I avoid larger blocks of colour and do all my bold designs in black or grey.

Anyway, back on topic, the clear vinyl is fairly thin and seems to hold the toner reasonably.  The white feels slightly thicker, but it doesn't take the toner as well - both colour and black will come off if bashed.  I have tried spraying with automotive lacquer after printing on white (see the Cabra Holdings and Lok-Tin designs above) - this was actually lacquered over a year ago, these are remnants from another sheet I made.  The problem is a) the lacquer causes the sheet to roll up as it dries, which makes it a pain to store, and 2) the lacquer itself flakes away when cut, taking the toner with it - see the ragged edges on the Cabra Holdings sticker.  If I cared enough, I would lacquer the stickers after they were in place, but I either use these stickers on cars that won't get bashed, or on cars that are supposed to get bashed, so it doesn't really matter.

Both products stick extremely well to smooth lexan and are pretty good on the less-than-mirror-finish surface of my badly painted ABS bodies, although they will leave residue if peeled off.

Neither product will form around curves like Tamiya decals, so I only stick mine on flat areas.

[BuggyDad 4474]

Thank you. That sounds ideal for me. 

4 hours ago, Mad Ax said:

I either use these stickers on cars that won't get bashed, or on cars that are supposed to get bashed, so it doesn't really matter.

As a rule, my use would be just the same. 

[Nikko85 3453]

On 11/8/2022 at 12:44 PM, Gebbly said:

This is all fascinating. The amount of detail you go into is brilliant and so educational, I'm loving all the info on wiring up LEDs and arduinos and getting them working. The wiring is looking extremely tidy, very professional. Giving the fuel tanks an actual function as storage was a good idea too.

I definitely approve of the correct technical jargon  : "hazard flashy flash flash mode", "pluggie-innie plug for the LEDs"

Maybe you could be coaxed into a little video clip of the lights working?

Brilliant job. Keep it up.

Yes. After about a decade of service my kindle broke last night, so just read this thread from beginning to end before bed, a cracking read.

[Mad Ax 9313]

3 hours ago, Nikko85 said:

After about a decade of service my kindle broke last night

y'know, I love my Kindle, it's convenient, easy to carry and nice to read in the dark.  But I never once had to switch a paper book off and on again because it wouldn't change page, I never worried about a paper book breaking if I accidentally dropped it, and if the worst happened, and it landed in the bath, I could probably replace it at the bookstore or online for pocket money.

Also when I fall asleep holding a paper book, it leaves smaller bruises on my nose.

On the other hand, I do like that I can change page on the Kindle with my nose so I don't have to disturb the blanket and let cold air in.  Paper books need a nose-operated page turning feature.

[Mad Ax 9313]

I finally got around to doing a bit more on this rig.  We decided that this truck will get its first public outing at Round 1 of the Iconic Cup, which coincidentally starts on April Fool's Day.  Exact details are top secret, but I need the truck to be functional and looking good for the big day.

One thing that's always bothered me is that the rear wheels sit further in than the front, so it kind of looks a bit like a lobster.  Or one of those weird kit cars which is a motorbike on the back and a car on the front.

Widening a Tamiya axle is usually as easy as buying deeper hexes or one of those hex extender things with the barrel nuts, but the big rig axle uses a splined hex, and I can't find anyone who makes a wider splined hex.

My original plan had been to have some spacer plates made that would sit behind the stamped wheel parts and the hub boss with the hex fitting machined in, but I realised it probably wouldn't be too difficult to make something myself, since it wouldn't be visible and didn't have to be tidy.

I started by dismantling a wheel, to use as a template.  It was a bit awkward since the wheel has a big wide hub hole but the boss has the usual 4mm hole.

Anyway, with a little bit of guesswork, I came up with this, using some 3mm alu sheet.

My marking / punching / drilling went wrong somewhere down the line (it always does, I can't seem to be accurate to more than 0.5mm anywhere but I'm not sure where the inaccuracy comes in) - so I drilled the holes to 3mm, not the 2.5mm of the wheel screws.

This is starting to look like something Danny Huynh would make.

Not sure what these look like.

[Mad Ax 9313]

I screwed them all together and used a stepped drill to make a 10mm hole down the middle.  I had to attack it from both ends and took some chunks out of my stainless screws.

After a lot of effort (way more than it was worth) I smoothed one of them down and even had a go at polishing it, with the drill spinning flat out in one direction and the bench polisher spinning in the other.  My cordless drill doesn't really have the rippums for this kind of thing and I couldn't be bothered to get the corded one out.

Since the parts will be unseen, I resorted to plain old elbow grease and manual filing to get the rest down to spec.

I had originally planned to mount these behind the stamped parts, but then I remembered there is a subtle problem with the wheel and tyre combo - the wheel inners distort the edge of the tyre and make it look a bit odd (the same way that 80s jeans tended to give everything a shape that you just don't see these days).  By fitting the spacer between the front and the back of the wheel, the tyre sidewall has a much more natural shape to it.

Updated spacement is visible from above.

 

[Mad Ax 9313]

This wide shot suggests there is still a bit more to go

It was quite a lot of work to make these, and really I need 5mm minimum, which either means buying thicker alu sheet or making two lots of these all over again, and tbh, I just don't fancy it.  The other problem is I have used up 3mm of the thread on the wheel screws, and said screws are not of the usual European metric flavour, so I don't know what the thread is to buy longer ones thereof.

Instead, I'm wondering if I can araldite two splined hexes together.  I could potentially even drill and pin them so they won't break apart.  I'm not sure how many spare splined hexes I have, and I don't think it will work with plastic ones.  There's loads of thread left on the axle shafts, so there's lots of scope for widenage.

The other thing I have started over the last couple of nights, is 3D designs for the front light buckets and radiator.  I had hoped to be able to cut the lenses out of the OG Blackfoot grille, but after weeks of careful sanding and scoring, I ended up going too far and ruining it.  So I'm back to using the plastic slam panel that I cut out of ABS, which should make it look like the front trim and grill is missing, for a really aggressive look.  Fingers crossed I can get that printed and fitted and all the lights wired in before 1st April, with two more rounds of Rallycross racing, a family party and a weekend break in between - plus I should probably go over the M03 before I put it on the tarmac...

[Mad Ax 9313]

I did some work on the front end of this truck last week.  I'm hoping to debut this truck at an event at the start of April, and I didn't want to show up with a completely missing front grille, or some hacked and ruined affair, so a week ago I printed off these badboys.

The light buckets and radiator are 3D designed that I knocked up myself and printed in resin.  The grille panel I made some time ago out of plasticard and ABS shapes.

The radiator looked like it hadn't printed properly, but on closer inspection I think it was resin stuck in the recesses that didn't get washed out, and has now cured in place in natural light.  Ah well, it'll do.

I painted the light bowls with Tamiya chrome silver, which isn't really very chrome.  I have some spray chrome which is way better, but it's too cold for spraying, and I wasn't sure it would work well in those narrow bowls.

As is normal on a resin print, the holes (3mm for the indicators, 5mm for the headlights) had closed up, so I redrilled them.

[Mad Ax 9313]

The grille panel was made a while back, and I glued on these H strips because I thought they looked about right, but I shouldn't have covered the area where the light buckets will go.

I spent a while with a scalpel getting it all off

I cleaned up the overpaint on the bowls with fine sandpaper and glued them on with superglue.  I wasn't sure regular plastic cement would work on resin.  In fact I wasn't sure the superglue would work either, as it all came off at one point, but after putting it back into place it seemed to stick better.

Done

[Mad Ax 9313]

I wired up some LEDs, hot-glued in the radiator, then hot-glued the entire cabundle into the front of the body

and there we go.  A rough-and-ready truck that's missing its chrome front grille surround

looks pretty mean, if you ask me

It looks even better in natural light, although I probably should have painted the white parts black first :facepalm: 

I'm quite pleased with that  

[Mad Ax 9313]

Later that day, when the sun had gone down, I would come back to the truck and put on a servo plug for the front lights.

it goes a bit like this

I'll be able to drive this one at night  

The indicators flash, and on this frame they were off, but they do work

[ad456 331]

This thing is meaty looking, the tires in the bumper is a great touch. Cracking build dude!

[Nikko85 3453]

On 2/22/2023 at 8:48 PM, Mad Ax said:

This wide shot suggests there is still a bit more to go

It was quite a lot of work to make these, and really I need 5mm minimum, which either means buying thicker alu sheet or making two lots of these all over again, and tbh, I just don't fancy it.  The other problem is I have used up 3mm of the thread on the wheel screws, and said screws are not of the usual European metric flavour, so I don't know what the thread is to buy longer ones thereof.

Instead, I'm wondering if I can araldite two splined hexes together.  I could potentially even drill and pin them so they won't break apart.  I'm not sure how many spare splined hexes I have, and I don't think it will work with plastic ones.  There's loads of thread left on the axle shafts, so there's lots of scope for widenage

 

Could you 3d print an adaptor that fits between the spline hex and wheel? Could slot over the hex then narrow again the the same hex as original to essentially make a much longer hex?

 

[Mad Ax 9313]

37 minutes ago, Nikko85 said:

Could you 3d print an adaptor that fits between the spline hex and wheel? Could slot over the hex then narrow again the the same hex as original to essentially make a much longer hex?

 

I was considering this, and it's a possibility.  It probably wouldn't take long to print a test piece.  My resin can be brittle, and cracks easily, so it might not stand up to real world use, although it's not like this rig will ever see hard trail use - in fact unless I start attending proper model exhibitions I doubt it'll get run more than once in a year.

I considered 3D printing all-new wider splined hexes, but there's no way the splines would last, they'd strip out faster than a Tamiya screw under a Phillips driver.

[Busdriver 6209]

23 hours ago, Nikko85 said:

'm not sure how many spare splined hexes I have, and I don't think it will work with plastic ones. 

If you join two together and pin them then only the inner one needs to be splined? The outer could just be normal meta or plastic?

[Mad Ax 9313]

10 hours ago, Busdriver said:

If you join two together and pin them then only the inner one needs to be splined? The outer could just be normal meta or plastic?

Outer metal ones will work, but I think all the alloy pin-type ones I have are machined, not cast, and somehow in my head that means they'll harder to drill accurately.  I don't know why I feel this.  The cast ones have three recess arcs on the back which I was hoping I would be able to insert the pins into for alignment and gluage.  Although I think I'll try the 3D print option first, it's an intriguing idea and one that might be useful for other projects further down the line.

[Mad Ax 9313]

So, I decided to go with @Nikko85's awesome idea and print off some hex extenders.  There's plenty of thread on the axles, because they're designed for big rig wheels, so I had scope to bring the wheels out a fair bit.  I allowed for a 5mm inner hex and 5mm outer hex depths, for plenty of bite on the axle and wheel hub, with a 2mm transition in the middle.

My first test prints were no good - they came out way too small.  It is known that resin shrinks a little when printing, but I think the shrinkage ratio varies depending on the size of the design.  I know I printed some 1.9" touring wheels a while back and the hexes fit perfectly on the axles (in fact I must revive that project, as those wheels looked awesome), but this much smaller design didn't work at all.  The outer hex would spin in the wheel without engaging, and there was no way the splined metal hex was going to fit in the adapter.

I did a few more test prints at different sizes, including a +10% option that worked well enough, although the hex was a bit tight.  In the end I printed off a bunch at +11%, which were still tight on the inner hex and more comfortable on the outer hex.  I could probably go to +12%.

Anyway, here they are.  Grown direct off the foot so there's no support mess to clean up (where possible, I design everything this way - the supports leave such a horrible mess on the print).

The hex is a snug fit, but it works.  I thought the block might split when I was pressing it in, but it was still very slightly soft, which might have helped.  I expect I'll have to crack it if I want to get the hex out later.

Here you can see the difference in width.  Definitely noticeable.

[Mad Ax 9313]

et, voila

 

[Mad Ax 9313]

I found a spare fuel can with mounting bracket while tidying up last week, so I decided to add it as a scale detail on the back of the rig.  I think the rear needs a few more scaley bits, but there's time for that later

Finally, during testing last week, the tail flap wasn't come down freely.  It'll kind of void the point if I have to walk over to flip it down manual when I'm towing cars away at the track.  This spring was already fitted to solve this problem, but it wasn't solving the problem, so I took it off and added a little extra kink with some pliers.

I think that's pretty much it for now - it's all cleaned up and ready to head off to Round 1 of the Iconic Cup on Saturday.  Fingers crossed it doesn't break or let me down, and that nobody gets offended when I tow them away from the concourse.

[Nikko85 3453]

Amazing, that's the exact design I had in my head. If those do fail, let me know as I can print at work.