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Guypie's Bike Builds - A paint job and more!


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I welded on the chain stays next, then decided to pop a crankset on to see if I managed to stuff up the chainring clearance. Turns out the chainring clearance was fine but the crank arm on the drive side had a slight issue:


Oh dear. So I put together a dimpling too to make a bit of clearance like so:


A bit of a squeeze and things were good to go!



I might need to revisit this later as under load it might flex into the crank arm but thats a problem for future Guypie.

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Next up is getting set up for bending seat stays. I bought a 3 ton arbor press cause I figured it would be nice piece of kit to have for fabricating things. The seat stays are 5/8" tube .049 thick (about 1.2mm, most of the other tubes are .035"/0.9mm for reference) so I needed to make some tooling for the press to bend these, hopefully without kinking. I turned some form tools out of 51mm ali I had lying around and then turned off the bottom of one piece for the press tool.


The piece to the left I needed to cut in half for supporting either side so I resorted to the scary tablesaw of death. I screwed it down to a sled with a piece of angle iron and hid behind the sled while feeding it through.


My gamble with tablesaw russian roulette paid off and the part was cut fairly cleanly, though not quite as even as I had hoped. Still, didn't really matter for what I had in mind


Gave it a press and the bend came out...


... with a horrible wrinkle on the inside. Sigh. This photo actually makes it look far worse than it is, so I just went ahead and used it anyway considering this piece of material is about $30 worth @ 460mm long. For the second stay I did some file work on the upper tool to increase the radius of the bending form and it was much better.



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Loving your work so far.
I have been using a pipe bender to bend tube recently cos I'm cheap, I have found a couple tricks help to minimise the kinks. First is packing it full of sand (ram it then just put some tape over the ends) and second is to use a tight fitting form where you are bending it to stop the tube from flattening out, try using one of your slick forms in place of the white one.
There are probably better ways than mine like using an oxy set but we use what we have :)

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Thanks for the suggestions, will have to give springs and/or sand a jam for the next lot of bending I do.

Seat stay 1 in place:20210806_172421.thumb.jpg.b1880337e632bb2cc579485ad1446c0b.jpg

Then seat stay 2:


These were all hand files because I was too lazy to make a seat stay mitering jig. I think I will for the next one cause one is a little bit higher than the other due to it needing more filing before ending up with a nice tight joint which bothers me slightly. Though you cant see it unless you are looking for it so its really not too bad.

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Added a brake tab to this last weekend




And thats all of my argon until payday comes around. I have be puttering along doing all the non weldy things for the last week. I put a little bridge between the chainstay and seatstay as apparently disc brakes are too much for skinny little tubes to handle long term.



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get some high silver content silver solder and flow it with map gas,


or for a head badge, use this style of rivet

Pack of x6 Bicycle Head Badge Rivets Vintage Retro Steel Bike | eBay

they also come in brass. hammer them in, to remove cut a slot in the head and unscrew


for something like that, some decent 2 part epoxy glue will hold it no worries. Or use badge tape like for a car. i stuck the badge back on my bike with some of that and its been on there for years


JBweld probably would work too, i have some securing the bottle rivnuts on my touring bike that were a little loose. It also survives powdercoating if you are into that

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@GuypieThis is really cool. I like the asymmetric chainstays they make me think of a BSA  track bridge.

When I bent the tubes for the rear of the my Panther replica I welded one end shut, packed them full of sand, then welded a large nut on the other end and wound a bolt through it and down into the tube to hold the sand as tight as I could. 

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It's been a little while since I updated this. Things are moving along nicely, though waiting for stuff to arrive off aliexpress is currently jamming up the works but there is plenty for me to post about for the time being.


The last piece of tube to go in the frame was cut and mitred by hand, it's a bridge for the seat stays. I decided against putting in a chain stay bridge in after lots of research, apparently they were originally added to bike frames as a attachment point for the mud guard and serve no purpose past that. I checked my Ragley hard tail and it doesn't have one and I give that bike a seriously hard time so I think it should be fine without it.


Next up was to get started on the fork. I mitered the crown section that @ThePog kindly donated to make it a bit narrower. To get the mitre on the right angle in relation to the steerer I needed to chock up the rear end of the fixture. It ended up being a bit of a compromise between getting the right angle for offset (I think it was about 6 degrees) and the centre height of the tube correct for boring. So it ened up being mitered on centre at 1 or 2 degrees less than ideal and I went in there with a file afterwards to tidy up the join . Probably could have gone a bit narrower as it still has clearance for a 4" tyre which it will never have, but the shape looks kind of cool and a bit different.


There's about a 2 degree taper in towards the dropout. I recon it looks kind of cool. Axle to crown is 450mm, Offset 65mm.

I decided on the offset after reading up about tyre flop and mechanical trail. I found a calculator on the video below (its in the description) and put in the specs for a bunch of different bikes and decided to go to the far end of high offset.

I figure this bike can be a bit of a test bed for steering geometry for me to figure out what to do for the next bike, as such it will probably end up getting 2 more forks made for it. Another 450mm a-c and 35mm offset which would be the extremely low end of offset for this bike, and another with offset determined by what I like from fork #1 and #2 and a-c height closer to 410mm. This would bring the BB height down by about 20mm, steepen the seat tube angle and headtube angle by about 2 degrees.





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Nobody likes to be dehydrated.

Therefore every bike needs a drink bottle holder! After having a rummage around I happened to have the right tap and drill in my stash of bits so I turned up some bottle bosses on the lathe and drilled the down tube for a bottle cage


A lot of the bits from here onwards I would really much rather have bought than made, but no where in NZ that I can find sells frame building supplies and I am too impatient to wait for 1-3 months for stuff to turn up from USA/UK.

I tig brazed these in, it is very difficult to get the silicon bronze to flow and I really didn't want to melt the base metal so amperage was pretty low.20210819_135923.thumb.jpg.282117a6d0217bd611ac9acd36b5c6fb.jpg

Came out a bit lumpy, quite a lot of filing and sanding later it looks like this


Still kind of lumpy and weird, but good enough considering it will be hidden by a bottle cage once the bike is all together



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2 minutes ago, tortron said:

could have used a rivnut ;)

i ebay'd some vintage braze ons a while ago, probably got a pack floating about still

What kind of braze ons? I have made what I need for this frame but could be keen on some for the next frame. It feels a little ridiculous spending an hour to make a $1 part but lockdown means there's time to kill so its not so bad.

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I put the wheel in with a rotor on and used a cable disc setup to clamp the caliper on to the rotor with the mounting plate bolted to it. Then tacked it to the frame as much as I could with that setup in place and then welded on alternating sides. The rear one is aligned mint, front I think has a tiny bit of an alignment issue but I will try tune that out later with a bit of bending/whacking/filing etc.

Are you planing on putting discs on your old timey mountain bike?

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