|615 forum posts|
Fished a bike out of a local pond using a piece of steel tied to a rope but since wheeling it back to my garage to restore it I found some odd ball fastners.
First is some Penta Plus sockets holding the pedals in
The second pair, holding the handle bars and seat on I don't even recognise.
Anyone recognise this bad boy?
Awful quality photos but my camera cant seem to differentiate the different shades of black too well.
Second part of the question is how do I get them out? A penta plus driver would be fairly easy to make if I had a dividing head but alas don't have one of them. Im not even sure how the geometry on the 3 spoke one works. A triwing driver didn't get deep enough in. Thinking off drilling them out but I feel the geometry would chowder up and drill bit. Any ideas?
14028 forum posts
Odd to have security fixings on a bike, are you sure it's not a stolen/dumped "Boris bike" or similar?
626 forum posts
Could it be a different size TriWing driver? Like these
What make of bike is it?
Not sure what lathe you have, other than a Pultra or similar, but are the bull wheel teeth divisible by 5, in which case a detent on there would do for indexing. If you've a large enough mill, you could even mount a miny lathe, or its headstock, on that and use as a dividing/indexing head.
Edited By peak4 on 22/07/2018 10:29:58
|pgk pgk||22/07/2018 10:19:15|
|1188 forum posts|
If you have a mill then the penta driver should be possible without a dividing head - just some round stock and cut the first flat by calculated depth and then rotate using a simple template of the angle against an engineers square? That should get you the plug shape and I'd reckon a good chance you could anneal and hammer some tube around that for the socket shape.
You mght be able to use a similar technique to make the second driver too with the stock vertical and PCD to plunge-cut the three radii for a template to hammer a socket to shape? If you don't have a cutter the right diameter then fly cut it down or use a boring head.
|1808 forum posts|
Yes agreed. I suppose cycle shops will have the drivers for these?
It’s bad enough that M7 is a standard cycle thread.
|Gordon W||22/07/2018 10:56:01|
|2005 forum posts|
I've just acquired a bike- all sorts of threads and heads. I suspect the head types are more for looks than security, as in "wow, it's got security bolts, must be expensive ". Also there are many different makers of the bits and all have their own ideas. Does not solve the problem tho'. I have a couple of assortment packs which do most ,but not the penta-lobe. Will get them when needed.
|Ian S C||22/07/2018 11:01:07|
7115 forum posts
The bike makers like selling expensive tools. The first one I'd take the Dremmel, and either cut a screw driver slot across the screw head, or do as I did for Robinson screws and modify an old Philips screw driver(in that case square), it's not too hard to eye ball a pentagon.
Can't help with the other one.
Ian S C
4205 forum posts
triwing? or tri-wing
avoids paying royalties to Posidrive and Philips I suppose
Edited By Bazyle on 22/07/2018 14:44:30
|Michael Gilligan||22/07/2018 15:33:51|
12061 forum posts
Bits are readily available, either individually or within sets like this: **LINK**
2904 forum posts
That triwing thing is just gagging to be shown a sharpened masonary drill. You might almost say the same about the pentagonal one. Might be a bit of a sod to loosen if it's been in a pond for a while, so not convinced I'd try to make anything to fit.
There's also the TIG approach which comes with the benefit of applied heat....
|Neil Wyatt||22/07/2018 18:09:56|
15008 forum posts
I see nothing relevant in your albums...
Ah they are there now, page must have loaded incorrectly.
As Jason says, you aren't 'receiving' are you?
Edited By Neil Wyatt on 22/07/2018 18:11:31
|David Standing 1||22/07/2018 19:21:02|
|1109 forum posts|
Nobody would want to 'restore' a Boris bike, unless they 'restored' it back to the pond it was dragged out of
|Alan Johnson 7||22/07/2018 19:25:06|
|53 forum posts|
Dremel, angle grinder, oxy-acet spring to mind as suitable "spanners!"
|Jon Lawes||22/07/2018 20:43:47|
225 forum posts
Only place I've ever seen Tri-wing is a BAE Hawk! Tri wing I thought look a bit narrower on the "wings" than that.
|Michael Gilligan||22/07/2018 20:53:36|
12061 forum posts
This is probably the most comprehensive and convenient reference list I have seen: **LINK**
|165 forum posts||
Thank you for that MichaelG, an interesting run-down.
|137 forum posts|
|1808 forum posts|
Wiki has the best listing of screw types that I’ve seen:
I’ve seen most types at one time or another but not the Bristol.
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
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.