@GeForce Junky, that’s a marketable item right there, lots of people would like a little help getting long Reverbs into their frames, or have bought one that won’t fit.

Because depending on the way the two surfaces interact that’s exactly what they are, given a great enough force to overcome any friction.

If it is two flat surfaces then its a pivot. If they are connected in a way that physically prevents twisting, they are not.

Easy proof – look at a 4 bar linkage (fsr/lawill/Macpherson strut) and try to think of a reason why it wouldn’t still allow movement with seized bearings given a great enough force. There isn’t one, its just the force required to move it is going to be greater than with good bearings.

Drew up some vintage kyosho parts and got them 3D printed.

Squirrel +1, although I hope that the frame does indeed hold up, what a great thing to make for your child. Good on you steveid.

squirrelking – Member

If it is two flat surfaces then its a pivot. If they are connected in a way that physically prevents twisting, they are not.

And you’ve chosen to believe based on no evidence that it must be the former.

@GeForce Junky, that’s a marketable item right there, lots of people would like a little help getting long Reverbs into their frames, or have bought one that won’t fit.

+1

Two points on that brilliant kids bike:

I’ve held that back end, because I built that wheel – that’s a very solid joint at the BB.

It’s effectively a triangle. Yes, there are two joints at the rear dropout, but they’re so close together that they’ll effectively act as one – and actually even if they were all loose then it wouldn’t move much as the action of moving the rear section upwards also rotates the axle downwards – it cancels out. Try making a model if you don’t believe me.

And you’ve chosen to believe based on no evidence that it must be the former.

Or rather I’ve chosen to present a very basic and fundamental potential engineering flaw based on face value. I did this for the benefit of the OP who may or may not have addressed the issue in his design. In return I’ve had nothing but uninformed crap thrown back at me by people who don’t know what they’re talking about. I might ‘only’ be a student but I am/was a fully qualified marine engineer and have 12 years experience working with mechanical systems so I do feel like I edge it on authority on the matter over a bunch of folk that seemingly cannot understand something that has been explained umpteen times now. I am not trying to be a smartarse here, as I said I saw a fairly glaring problem and was trying to do the guy a favour.

This is exactly the kind of groupthink engineers are taught to fight against, I’ve seen it first hand and the most famous example was the Challenger boost rocket seals where engineers were ignored by people who thought they knew better. And before you all get on your high horses, no I’m not comparing a child’s bike to the Challenger shuttle disaster, just the groupthink.

Ben – either it’s a triangle or it’s not. In this case it’s not, the proximity of the joints makes no difference. The difference in dynamic loading to that of static loading (especially with the loading from single stays) is what concerns me though, it’s all good now but after a bit of use where will it be? I do however concede that you know your onions when it comes to bikes and it’s hardly Fatty McFats touring bike, with proper care and attention there shouldn’t be a problem but with correct design there wouldn’t be one in the first place.

As I said in my first post it is impressive, it’s a very lovely piece of work and I’d be proud of it.

Anyway, I’ve said enough on the matter, it’s really nobody’s business but the OP (and anyone who may have seen it in the flesh) so I’m done with the sniping. I’ve made my case and justified it far more than I should really have to so I’m done.

Fatty McFats touring bike,

That’s another thread.

I’m sure the OP took it in the spirit it was intended.

london_lad_liam show us more. What are you building up?

@GeForce Junky, that’s a marketable item right there, lots of people would like a little help getting long Reverbs into their frames, or have bought one that won’t fit.

Wasn’t there a thread in the last day or so with someone looking for a low stack saddle and considering other options such as shorter cranks and thicker pedals to overcome just this problem?

I suspect at commercial rates it’d cost more than a Reverb

GeForce Junky – impressive!
Just a slight warning (that might not be important), but saddles can sag quite a bit in the middle. It shouldn’t make it uncomfortable, but it might not feel quite the same when sat on.
I found this out because the original Maverick Speedball had a post up there that even my low weight used to activate the dropper!
I ended up finding a lower profile bolt.

(internet pic)

For jimfrandisco who requested some ‘making of’ images:

First we made 2 drawer units to fit some ebay 700mm full extension runners. We used pocket holes front and rear so they are all hidden. Routed a groove on all the sides for the drawer bottom (6mm ply).

Then added the frame on top of them around the room to take the ikea bed slats

Added a partition for the triangular cupboard section.

Then placed all the fronts on after measuring 3 times cutting once. All from the same sheet of ply.
Used spacers to get it all right. Everything fitted first time which was a relief.

I don’t have any pics, but we fixed the handles to the drawer fronts first with recessed bolts, then drilled oversize holes into the drawers, so that when we used pan-head screws and washers there would bee a couple of mm adjustment available.

We started bottom-right with all but one drawer removed and screwed each drawer front on from behind using spacers and clamps.
Worked our way up the first set then the second.

Very slow work, but our care paid off!

Cupboard is fixed using kitchen cupboard hinges, so we needed to drill 35mm blind holes into it, but I already had the correct bit from the bathroom cupboard project.

@arching london_lad_liam show us more. What are you building up?

So the first two green bits are from a Kyosho Lazer ZXR

Drew the from arm over the last bank holiday…I was bored and find it quite therapeutic (there also quite hard to get hold of if they do break)

The knuckle bit as also for the same car, I have modified so that an m3 nut sits in the bottom (instead of screwing directly in to the plastic) so gives a much stronger front end.

My other project was a Losi xxx CR2 (which had been converted to mid motor) but the old gearbox sad very high so I designed a printed a lower version.

The green parts where printed with an SLA printer, The grey gearbox was printed on a SLS printer with a graphite additive and they white gear box was a normal FDM printer.

Started Drawing bits to mainly expand my knowledge on 3d printing and 3d Cad to some degree.With 3d printing there is SO many filaments that you can choose to vary how your end product comes out.

Want next try the aluminium 3d printer but thats mega bucks 🙁

squirrelking – Member

Or rather I’ve chosen to present a very basic and fundamental potential engineering flaw based on face value. I did this for the benefit of the OP who may or may not have addressed the issue in his design. In return I’ve had nothing but uninformed crap thrown back at me by people who don’t know what they’re talking about. I might ‘only’ be a student but I am/was a fully qualified marine engineer and have 12 years experience working with mechanical systems so I do feel like I edge it on authority on the matter over a bunch of folk that seemingly cannot understand something that has been explained umpteen times now.

You are completely missing the point. The engineering facts which you’ve thrown around are all correct, and in fact obvious- nobody is “not understanding them”. The issue is that your sound engineering is all building on an assumption not a fact. And you even said so:

squirrelking – Member

That’s why I only assume the joints aren’t restrained as that’s how it appears

Maybe the confusion because it was described as a swingarm?

I have zero engineering experience but it looks sound to me 😉 triangle bolted at all corners will be fine I would have thought?

Edit lovely thing by the way!

Can I suggest that any further discussion of stevied’s bike should go in the main thread here: http://singletrackworld.com/forum/topic/how-hard-is-it-to-make-a-kids-bike

This is better as a fairly quick-fire inspirational thread of project pics

Smartphone holder bodged together from bits of scrap oak. Hoping it’ll make navigation a bit easier on my upcoming touring holiday. Also hoping it doesn’t break and ruin my phone…

^ Steampunk iPhone holder. I like 🙂

I know there are some knife guys on here. I wanted to make my dad a knife for his 60th, I started about 6 months out so I had plenty of time, but for various reasons he’s 63 next month and I put the first couple of coats of oil on the handle today.

It’s the first time I’ve had a go, and I’m pretty happy how it’s turned off out. I bought the Damascus blade from somewhere in the US. The scales are mallee. I let the pins get a bit hot when sanding and it has burnt the surrounding wood, but other than that it’s all good.

Oooooh! That’s nice.

Latest project complete.
An adjustable shelf system for eldest son’s room.
As usual made from my huge stock of 15mm birch ply offcuts.

Note for future reference 25mm dowel is definitely not 25mm …or round.

In my usual style, the requirement for drilling 72 vertical holes justified the purchase of a new tool…

finished latest knife just before holiday, there for a holiday picture of said knife
Sycamore with a carbon rod as pin
[url=https://flic.kr/p/UrZSwW]5J4A9244[/url] by msh_sco, on Flickr

@ Ishouldbeworking, very nice wood and handle.

Just a little something I’ve been working on. A new box for my RM20 combo, now a head.
Had to learn a lot of new skills but I’m pleased with how its come it. Been going to a community high school wood working class.

Just need to oil, stain or wax the wood and find a nice handle for it and rock the f*&k out.

This whole thread is inspiring.

Northwind – Member
@GeForce Junky, that’s a marketable item right there, lots of people would like a little help getting long Reverbs into their frames, or have bought one that won’t fit.

I agree, small wife and small kids would all like this.

66deg – Member
Table and speakers all my own work but I take no credit for the horse and wraith.

SEAS cast magnesium cone drivers? Did you design the x-over and bass loading too?

One of the charming locals broke into my garage by splitting the rubbish old door in half. So, with the compensation that he had to pay when he was convicted (thank you Netgear Arlo!) I bought some wood and Screwfix’s finest cheapest router and got to work.
Old door:

I forgot to get photos of the mortices and tenons before I started putting it together, but they looked like a rougher version of this:

Then the frame went together:
There are wedges in the ends of the tenons (that’s what the slots in the tenons are for). The wedges open out the tenons once they’re in place and mean the door can never be pulled apart.

I routed a groove for the front planks to sit in, so they would be flush with the frame:

Fitted the diagonal braces:

Treated the frame with preservative and a coat of varnish:

Fitted the planks to the front. I’d already measured them for length and varnished them. I had to cut two long, thin strips to go down each side to get the planks central in the door:

Back of the door (with an annoying bow in the middle rail):

I put a few more coats of varnish on the finished thing, epoxied any external screw heads, fitted the hinges and locks, and voila:

It’s a little rough in places from silly slips with the router or sloppy morticing, but not bad for my first bit of joinery.

The instructions I followed are here: http://wiki.diyfaq.org.uk/index.php?title=Making_a_framed_ledge_and_brace_door

Nice work! Hopefully sturdy enough now!

Still needs a bit more clay and some trimming but pretty much finished

SEAS cast magnesium cone drivers? Did you design the x-over and bass loading too?

Well spotted on the seas drivers, to build they took about 130 hrs work but I was being a bit fancy here and there with the cabinets .
They are called Thor evo 4 and came in kit form from Intertechnick who also offer a Xover build option which I took full advantage of, they are mass loaded transmission line which seas commissioned Joe D’Apolito to design to show off their drivers .
I didn’t add up all the cost to accurately but they are close to 1k each but have proved to worth every penny sound wise 😀
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Thanks for all the kind words about the bike.
@ squirrel, you had me worried for a minute but then I went and sat on the bike (all 14 stone of me) and it is rock solid, not a jot of movement, so it will be fine for my daughter who is considerably lighter than me.

The quality of the other stuff on here is amazing, some really skilled folk out there 😀

Bails.

Get some of hinge bolts so the exposed pins aren’t an issue.

Stevied – glad to hear, that’s an absolutely gorgeous bike!

Some recent 3D prints. Been calibrating my new machine.
A little robot, couple of pyramids with captive balls, a skull (detail wasn’t so good on this) and an iPhone case.
Quite pleased 🙂

[url=https://flic.kr/p/W6VFr3]Some recent 3D prints[/url] by tom harrison, on Flickr

Get some of hinge bolts so the exposed pins aren’t an issue

Already done thanks.

I made another exhibition of the student work on the furniture making course what I done teach on, as I do every year at Warwickshire College.

This year a student got a commission to rebuild a bench for Kenilworth mayors that had rotted, so I made a tree to show it off as it’ll be in its final home. It’s made from mdf, and cut on our cnc router.

[url=https://flic.kr/p/W2HudW]Treemendous tree I made. Furniture Crafts End of year show 2017[/url] by Kayak23, on Flickr

Untitled by Kayak23, on Flickr

[url=https://flic.kr/p/Why1Gp]Untitled[/url] by Kayak23, on Flickr

Packable PVC Pipe Bunny Hop Bar, minimally modified version of https://www.youtube.com/watch?v=1rvR52M4uxQ by Ali Clarkson

I left the extensions at home, Danny Macaskill need not feel threatened just yet.

No pics but I seem to have inadvertently converted my daughters coaster hub to a freecoaster when I pulled the brake shoes out. I expect I’ll be fitting a gyro and showing off ramps before long…

Couple of brackets to hang a bike from the wall: