Custom CNC Services
#1
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Custom CNC Services
Kind of an odd ball question, but are there folks here who own or operate CNC machines that can do custom part requests? For example, I have an older mountain bike which has a 3x chainring and I want to fit it with a chainring guard and/or bash ring. Thing is, I don’t want to remove the outer chainring (making it a 2x) in order to do this, as I want to keep all three gears in place.
For reference, my MTB uses a 3x chainring with four bolt holes, with the biggest gear being 42-teeth, and a BCD of about 135mm.
For reference, my MTB uses a 3x chainring with four bolt holes, with the biggest gear being 42-teeth, and a BCD of about 135mm.
#2
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Sure there are hobby people w/ CNC stuff, although a one off can be easier to make on a manual machine often The Home Shop Machinist & Machinist's Workshop Magazine's BBS and Forum list | The Hobby-Machinist are two machine tool work forums I follow. Then there's the on line contract services like CNC Manufacturing, Fast Quotes & Free CAD | eMachineShop to consider.
When I read threads like this one I do wonder if the OP understands the real life cost of such a project. Andy
When I read threads like this one I do wonder if the OP understands the real life cost of such a project. Andy
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AndrewRStewart
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Design the part you want in CAD and send it to someplace like https://www.xometry.com/ to have it made. I think you'll be shocked at the price for a single machined part. It seems to me that your issue would be less of finding a bash guard and more of finding chainring bolts long enough to go through 4 rings and the crankarm.
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I find arguments against 2x to be less than compelling. Are you sprinting in the pro peloton on your mtb?
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designing a chain ring in solidworks is on the list of things to do. After designing some lugs to be 3d printed.
Considerably after.
Considerably after.
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Here is a bash guard that will fit a 4 arm 104 BCD crankset, which is what the Truvativ Isoflow 3.0 should be. https://www.ebay.com/itm/11311473077...Cclp%3A2047675
How to mount it will be a challenge and I question the need for such things. In 20 plus years of off road riding, I've only damaged one chainring.
How to mount it will be a challenge and I question the need for such things. In 20 plus years of off road riding, I've only damaged one chainring.
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Here's the last bent ring I did, also the first Don't think a bash guard would have made any difference. Andy
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AndrewRStewart
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#9
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Well, no. The MTB is older, true, and I can't see burying the bike for a new one and/or replacing the entire crankset if there's a soul out there looking for CNC or even 3D printing work.
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Sorry for belaboring this. You can get 2x chainrings and a bash guard for that crank, I'm not advising you to discard the bike. It's just that I suspect you don't really need the 48 or whatever it is and that solves the problem. The whole world is going to 1x on mtb for pretty good reasons. But that means a whole new drivetrain, whereas 2x doesn't. Unfortunately, only 1x is easy to get. At least that was the case a couple of months ago when I tried to replace the 2x chain rings on one of my mtb cranks. It was for my gravel bike, so the crank having 42/28 chain rings works pretty well, and I didn't want to get a new drivetrain. I didn't search amazon/ebay/alibaba though, might be able to get parts there.
There used to be a guy that machined chainrings that hung around on a couple of bike related forums. He also had some contact with a CNC community I'm part of. I think that he started Wolftooth, but I can't find any evidence of that. Even if I'm wrong about who that was, it took him quite a bit of effort to get to the point where he was making usable chain rings. It's a lot of effort if you aren't doing it already.
You're actually asking for design/process development/build help so probably nobody is going to want to do it. My friends and family rate on that would surely be enough to buy a mountain bike at a bike shop.
There used to be a guy that machined chainrings that hung around on a couple of bike related forums. He also had some contact with a CNC community I'm part of. I think that he started Wolftooth, but I can't find any evidence of that. Even if I'm wrong about who that was, it took him quite a bit of effort to get to the point where he was making usable chain rings. It's a lot of effort if you aren't doing it already.
You're actually asking for design/process development/build help so probably nobody is going to want to do it. My friends and family rate on that would surely be enough to buy a mountain bike at a bike shop.
#11
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You're making an excellent case in convincing me to just get a new (or new to me!) mountain bike, LOL!
Likes For Entropy_S:
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Design the part you want in CAD and send it to someplace like https://www.xometry.com/ to have it made. I think you'll be shocked at the price for a single machined part. It seems to me that your issue would be less of finding a bash guard and more of finding chainring bolts long enough to go through 4 rings and the crankarm.
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good job on that
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)
Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)
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that is called win win N+1
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)
Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or for Raleigh International frame fork 58cm)