DIY roller starter

[derek badger]

Dragged the inverter out and welded the end plates and shafts in. Not the best job I've done as I only had 2.4mm rods and couldn't be arsed to drive 30 miles to get some 3.2's so it had a few passes and some grinding. It's ugly as fuck, has some slag inclusion but it's full pen and won't be coming off.

Next jobs are to start cutting the 25x50mm box section up, mount the pillow bearings and sort out how to couple a 9" grinder to the shaft. Can't decide if I need to link both roller with puleys/toothed belt or chain/sprockets or just drive the knurled one for simplicity.

[David]

That will never start, its supposed to have an engine and stuff.....

[Mr. Dazzle]

Nothing quite like cutting, grinding and welding while on the beers though.

[demographic]

Nothing quite like cutting, grinding and welding while on the beers though.

Grinders are one of those tools that people who've not used them much think are ace. Big sparks and stuff "fuck yeah"
Spend a few hours with the noisy bastard things and the shine soon wears off.

When I worked for a company that made pressure vessels and later at a place that made pressurised steam boilers there was guys that spent half of their working lives grinding weld roots clean for another pass. I have a few grinders and will likely get a cordless one soonish but theyre a necessary evil rather than a tool I like.

And Badger? What kind of amps does that inverter chuck out and at what voltage? Ok duty cycle?

IIRC the person doing stick welding themselves will only get about a 33% duty cycle because of the time spent doing prep and cleanup.
MIG getting more like 66% but its a bit shite for welding bits up by yer decking cos the gas shield blows away and you get porosity.

[Mr. Dazzle]

I fucking hate grinders. Mostly cause I always drop them but they don't turn off when you do, so they scream away from you like a demented rat, reach the end of their cable and then flip around and coming screaming back at you

[Asian Boss]

I'm scared of my grinder too.

As for the OP, I'd have some sympathy if it had a left hand kicker and a 13:1 compression ratio but it's just an auld stroker, all you need to to is move it to the upstroke and gan it a proper kick.

[derek badger]

Nothing quite like cutting, grinding and welding while on the beers though.

It's all fun, until you've not got enough fingers to hold a can anymore.

[derek badger]

And Badger? What kind of amps does that inverter chuck out and at what voltage? Ok duty cycle?

IIRC the person doing stick welding themselves will only get about a 33% duty cycle because of the time spent doing prep and cleanup.
MIG getting more like 66% but its a bit shite for welding bits up by yer decking cos the gas shield blows away and you get porosity.

160A and 30%, and yes I could have used my little 130A mini MIG but as you say it's no good outside and I CBA clearing motorbikes out of the way and hoovering grinding dust off everything in the workshop. Plus the Sun was shining.

[iansoady]

I'm scared of anything with whirling sharp bits. As for noise - when I was an apprentice with the CEGB I was given a job making screw jacks to support eh ash troughs under the boilers in an old chain-grate power station. After welding and grinding dozens of the bloody things I'd have been happy never to see a grinder again.

[demographic]

I knew I had some pics somewhere.
Yeah the photos are crap, the originals are on a memory card somewhere so its just ones I found on my Photobucket account.
Car version.



12 volt one.

[Mr. Dazzle]

Mate of mine built one like the top picture and used it to start his old Guzzi. He managed to somehow 'slide' the bike sideways along the rollers while it was spinning and then machined a perfect groove in his tyre sidewall with a bolthead on the bike.

[derek badger]

Turns out go karts use 30mm axles and you can get split sprockets that clamp on, same size as the shafts I've welded to the rollers. I've ordered two and some 428 chain.

[cheb]

That's very convenient.

[demographic]

Mind surely a roller starter is just a practice run for a dyno?
Thread about making one starts to get interesting on this page...

http://www.oem-cycle.com/forum/viewtopi ... 9&start=10

[derek badger]

[derek badger]

More parts arrived this week. 9" grinder, flange bearings, M14 shaft, drive sprocket, 10A foot switch and a junction box.



Hopefully I'll get some time over the next couple of weeks to work out the build and start fabrication.

The see if I throw myself through the wall trying to start this...

[David]

Would you like to practice on my 441 Victor?

[derek badger]

After pissing about with metric shafts and sprocket bores or the drive source I gave up as nothing was in tolerance. So we've now got a 3/4" stainless extension shaft for the grinder with an M14 female at one and and male at the other. Its for a polishing mop and is 100mm long. Mounted to the shFt will be a 10T 428 go-kart sprocket with grub screws and a couple of 3/4" internal bore flange bearings and a wide flanged nut on the end.

The grinder has 3 hefty mounting points for the handle so I can use these to mount it to the frame.

Very surprised at how clean the Evolution mitre saw cut through the box section, nice bit of kit that.

Boxes of nuts and bolts have arrived and I'll tack it up and check everything is square before welding it. I've also got some wheels and feet to fit to the frame.

[derek badger]

Just realised the grinder needs to be flipped over and drive the other side of the roller....or it'll be running the bike wheel the wrong way...

[Rockburner]

I hope you're going to put a guard on that chain......