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I would like to machine this down to a cylindrical outer so that I can support it with a ball bearing. The thread for the cordless drill is 1/2" and the thinnest part of the outer is ~21 mm.

I want to weld a plate perpendicular to the left hand side of the chuck
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So even the rain that falls isn't actually going to fill our dams and our river systems

Talk to miles. It's probably easier to just make it straight out of steel and drill and tap it. He makes up custom shafts with bolts for all their wheels.

Steve
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Steven Martin
Twisted Constructions
http://www.botbitz.com

Definitely do that ^ Dylon also made his own hubs by tapping the wheel out i think to m16? then tapping out the center. Good solution indeed.

As for the drill press turns out the pulley is held on with a taper and that was loose. $30 impact socket later and all is sweet once more
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Yeah Phill we will have a crack at making it.

Welding Bizalloy 450?

So I gotta heat the biz up before welding right? How do I know how hot to do it and can I just use the swap n go propane/ torch I used for melting ali or do I need to go buy a new map gas bottle?
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

My take on it is don't bother. They do it to stop hydrogen getting stuck in the weld and then cracking out. The hydrogen travels through the super hot metal quicker or something like that, thus why they pre and post heat the metal, so it can seep out and not get trapped within the weld, bursting out later as a crack. That usually happens within 24-48 hours.

Soo i just weld it, then if it hasnt cracked in 2 days, all good. None of mine have, but i tend to just weld at rediculously high current all the time lol. Doing it the "proper" way, you have to heat the entire weld area up to whatever temp it is, i think about 170-200c, weld it, then keep it at that heat for a time after welding.

There's an interpass temperature too that states you have to let the area cool back down to this temp before doing another weld if its heated up again IIRC.

It's just a huge pain in the ass really to try weld a whole robot that way. i doubt anyone has ever done it The quality of our welds would be more of a problem than lack of pre/post heating

But if you read the datasheet on it (they usually have a special welding document) it might say you can use a certain stainless steel rod on them. 317 i think? Then no preheating is neccessary Im itching to try that out.

If you're stick welding the stuff im sure you can buy the special rod just for it.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Ah cool....thanks for that .....thats my style just do it and hope for the best....so i can just use regular sticks to hey?
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

I have heard of people putting the whole job on the bbq plate to heat it up, and do the slow cooldown after welding.
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The Engine Whisperer - fixer of things

I've done a similar job of welding up a car diff by pre heating the diff in the oven at 250'c removing the diff, welding and then putting the diff back in at 100'c for 2hrs, then turning the oven off and letting it cool off slowly with the door closed (3-4hrs).

I only used general purpose rods but I have heard of people using low hydrogen rods as well for such work.
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https://www.halfdonethings.com/

Sup guise.

Had to do some rather hardcore boring on the lathe today which was somewhat hellacious. Need a much better boring tool.

The rigidity of the machine is fine. It just seems the tool is crap and takes too much power to cut. a 1mm depth of cut stalls the machine immediately where as the diamond turning tool will happily rip a 3mm cut in the same material.

It's one of those cheap-o hafco carbides that come in the set. Looks like it has a huge negative rake so no surprises there.

Anyways, something with a positive rake would be good, but, i have zero idea about inserts. So damn many of them! Can anyone shed some light onto what would be good? Hafco has a TCMT boring bar but its $180 with the carbides. Can probably get something much better for that money over seas.

https://www.machineryhouse.com.au/L022

Also what about clamping methods. There seems to be a lot. The hafco ones im using have a little cam grub screw type setup and its really bad. Guessing the bolt down style is the best as in the above item?

Cheers!
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Two things that I have tried: first, angle the bar as much as possible like this:



This makes the bar resist twisting and usually allows for a more positive rake. You might have to grind some metal off the underside of the bar to increase the rake. This isn't so helpful in deep & narrow holes, but it definitely improved results for me in some situations.

If you have a boring tool with a brazed-on tip. I read that grinding a more aggressive rake on the leading edges helps and it definitely gave a better result in the mill's boring head, allowing for a more positive rake.

give sei carbide in penrith a call, they really seem to know their stuff
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Mechanical engineers build weapons, civil engineers build targets

I want to make some custom carbon fibre tubes. The parts I want would be varied with some having curves and others having a taper or a mixture of both. I've been studying how to get the results I want and it seems simple if you read this page: http://cftrumpet.wordpress.com/2012/11/23/my-first-curved-tube/comment-page-1/

At the moment I only have $50 to my name and I'm wondering how I could make a mold? How much would it cost to get one made?
I have an example below

Commercial moulds are very expensive. A home-made one that size would still not be cheap as you would need to make it from Delrin or something similar that machines smoothly and won't flex while making parts.

You might get away with HDPE if you can put up with a rougher surface finish. I would use two location pins at diagonally opposite corners and plenty of bolts along the mould path to keep the two sides tightly together.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion

Well surface finish isn't too important yet since I would be prototyping/learning/playing. I was thinking HDPE for the moment and if I did send it out to get made that the shop might try to do too good of a job and cost me too much for something that may be single use.

Could I 3D print and sand/polish something to do the job for a prototype?

Angus or Steve might have an opinion on that - my experience with milling moulds is that the rougher the surface is, the harder it is to separate the mould, even with top quality release agent.
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Australian 2015 Featherweight champion
UK 2016 Gladiator champion