# Duplicate a CNC machined part?



## Mountain Cycle Shawn (Jan 19, 2004)

Is it difficult to duplicate a CNC machined part (a disc brake adapter) if you have an example to copy from or do you need the drawings or computer code to make the part. Hope that makes sence. Here is my dilemma: I have been searching for a rear disc brake adapter for my early Mountain Cycle Moho STS hardtail. Mountain Cycle made a bunch of them at one time, but sold out of them a long time ago. Mountain Cycle, with the new change in ownership, no longer has the drawings or plans or computer code or whatever it takes to make them. I found a guy in Italy who has an adapter. He knows a CNC guy who has done some work for him, so he is going to see if the guy can duplicate it. So again my question is: Is that hard to do or do you need plans, code or whatever? 

Here is an image of the adapter and my dropout. I am going to use the bike for street only. I am going to give the frame a fresh mirror polish, put some slicks on the 26" wheels, a SID 100 fork, disc brakes front and rear and make it a 9 speed, with a vintage Cook Brothers crank set with a 46 tooth chain ring and 11-34 in the back.


----------



## joelsman (Apr 4, 2006)

much easier with the #'s but can be done easily enough.


----------



## disease (Nov 27, 2007)

If you are going to CNC it, then having the original wireframe model (probably an IGES file)will make it much simpler. Otherwise, you will have to construct another file from scratch. The CNC machine will not be able to determine a tool path without it. It could get expensive. Even with the IGES file, it could get expensive, since you are only producing one.

The part could be duplicicated with a simple manual milling machine, if you opt to eliminate some of the more elaborate details and simplify it. 

The critical features are the mounting holes for the disc caliper, and for the frame. You could probably fashion a very crude one yourself from a piece of flat stock, using only a drill press and a hacksaw. It would be ugly, but it would function.

Either that or look for a bolt on solution like the A2Z DM-UNI adapter. they are readily available on eBay for under $30.00. There is also a cheap Brake Therapy clone on eBay right now from a seller named ChaserTech.


----------



## patineto (Oct 28, 2005)

disease said:


> Either that or look for a bolt on solution like the A2Z DM-UNI adapter. they are readily available on eBay for under $30.00.


If you are taking about this adaptor,I will not recomend it.









I purchase one for my tandem, but I only have dragging problems with it (Is just not aling, plus rocks fore and aft under braking wearing out the paint and maybe even bending the tubes of the frame a little), to the point I'm making my own that will attach to the left brake post to isolate the rocking movement.


----------



## disease (Nov 27, 2007)

patineto said:


> If you are taking about this adaptor,I will not recomend it.
> 
> 
> 
> ...


The DMZ-UNI was designed for thick aluminum dropouts, not for steel. I have one, and I would not put it on a steel frame.

I am not sure if attaching an arm to connect with the brake post will help you much. The designs which incorporate that type of connector do not depend on the connector to prevent rocking. It is there to transfer the load, that's all. They do not rock because they are connected to the axle in such a way that they are prevented from twisting.


----------



## Mountain Cycle Shawn (Jan 19, 2004)

No, Im not putting some cheesy ass after thought adapter on it. No real mountain bike should ever have to wear one of those. 

I thought it was pretty clear from my thread what I am trying to do. I want to duplicate an adapter that Mountain Cycle made specifically for this frame. Just like the one in the image I provided. Or, find one that someone is selling, but that rought has not panned out yet. 

Now if there are any frame builders out there who think they could make one for me, like the one in the image, just let me know. And I don't mean some hack job, I want something that looks good and works. I could send the frame to someone if I had to, which I assume I would have to. But on the other hand, I don't have the $ to spend a fortune on this either.

Thanks,
Shawn


----------



## Walt (Jan 23, 2004)

*Not gonna be cheap*

I would *guess* that having this duplicated to your standards (ie, works good and looks original) would cost $500+ for a single piece, unless you know someone with a CNC mill and some free time. Making something *similar* looking and fully functional, on the other hand, would be a much easier and cheaper proposition. I don't know if I agree that a hacksaw and drill are enough, but I wouldn't be all that surprised if someone crafty could make those tools do the job, either.

Get some graftons or something for it and bling it out v-brake style. I can't see the bike being worth the effort of having that part duplicated.

-Walt


----------



## SoloRider (Aug 6, 2004)

You need a machinist, not a framebuilder. It's not going to be cheap either. If you've got some drafting skill you could try emachineshop.com, still not cheap though.


----------



## Mountain Cycle Shawn (Jan 19, 2004)

Damn! Im not willing to spend that much. And I know, you know what your talking about. I'll see what the guy in Italy comes up with. And I'll keep searching for someone who has one. Or I coud buy a later frame that already has one. But for now, your right, A v-brake will have to do.


----------



## Mountain Cycle Shawn (Jan 19, 2004)

SoloRider said:


> You need a machinist, not a framebuilder. It's not going to be cheap either. If you've got some drafting skill you could try emachineshop.com, still not cheap though.


I know, but frame builders have the knowledge. And there is no "machinist" forum here.


----------



## patineto (Oct 28, 2005)

disease said:


> The DMZ-UNI was designed for thick aluminum dropouts, not for steel. I have one, and I would not put it on a steel frame.


Doh that makes sense.

Thanks for the advice


> I am not sure if attaching an arm to connect with the brake post will help you much. The designs which incorporate that type of connector do not depend on the connector to prevent rocking. It is there to transfer the load, that's all. They do not rock because they are connected to the axle in such a way that they are prevented from twisting.


I show you and explain you better what I'm going to do during the day.

but thanks for the great Imput for now.


----------



## heeler (Feb 13, 2004)

I have used companies that use laser scan to duplicate wire frame drawings from the original piece. It uses time of flight and defraction on a handheld scanner that keeps track of XYandZ and basically creates a wireframe from the outside dimensions of anything.

This is not cheap ($250+ for the scan), but if you needed to do a run of them it is much faster than re-creating the original by hand. We used it to create valve parts for 1940 vintage valves... It was cheaper than casting.


----------



## disease (Nov 27, 2007)

How much are you willing to spend, seriously?


----------



## Mountain Cycle Shawn (Jan 19, 2004)

Well, I was hoping to find one and be done with it for about $50. But it doesn't look like that is going to happen. If someone could make me an adapter to the standard as the one in the image, I would go as high as $200. I wouldn't be all that happy about paying that much, but I would do it. But it doesn't look like I can get one made for that price, so I guess I'll keep looking for one that is allready made. 

To tell you the truth, now that I am thinking about it I would be better off picking up a used later frame that already has the disc mount built built in. If I find an adapter I still have to drill a hole in the chainstay to install it, which means there is a chance of screwing it up and making the frame useless and having an expensive adapter paper weight left over.


----------



## disease (Nov 27, 2007)

No machinist will reproduce that adapter for $50. Maybe not even for $200. It is a very elaborate design. It's well thought out, and it looks good to boot, but it is not simple to duplicate.


----------



## Mountain Cycle Shawn (Jan 19, 2004)

disease said:


> No machinist will reproduce that adapter for $50. Maybe not even for $200. It is a very elaborate design. It's well thought out, and it looks good to boot, but it is not simple to duplicate.


I said, I was hoping to find one that Mountain Cycle made at one time. They were going for about $40-50 at the time. I know no one is going to make one for $50 for me.


----------



## superguzz (Jul 13, 2007)

hi, i am the italian guy with the moho sts disk adapter. I found it in the italian mc importer but now he finished it.....
i think if you could find the original drawings you could cnc it....
I also own an whyte porst frame, i found the pdf with the disc adaptor (a guy from taywan...) and i cnc it in a factory near my home....
it's not difficult to do it with the drawings, but without these it's near impossible....i think


----------



## Sim2u (Nov 22, 2006)

I'm sure you have either thought about this already, searched already on E-bay or perhaps some other smart cookie has already said this, but hey..."have you searched E-Bay" at all for this part yet...? Maybe worth a look.:thumbsup:



Mountain Cycle Shawn said:


> Damn! Im not willing to spend that much. And I know, you know what your talking about. I'll see what the guy in Italy comes up with. And I'll keep searching for someone who has one. Or I coud buy a later frame that already has one. But for now, your right, A v-brake will have to do.


----------



## Cheers! (Jun 26, 2006)

If you can get the part in hand, try to find a CAD designer. Have him/her model the part on the computer (solidworks, ProE) whatever. That part looks like someone who is good could model it in 1/2 an hour. Get the file and send it off to various local machine shops for quotes. Material wise it looks like it will be around 20 to 50 dollars for 6061-T651 aluminum, which will be plenty strong for your part. Machining time with fixturing looks like it will be 1 hour or less. If the shop is slow or you are willing to do a cash deal and you aren't pressed for time, you might get it done for 100 dollars cash, material included. Having the CAD solid model is where you will save money. I'm sure there is someone in your circle of friends who is an engineer or is a mechanical designer or knows of who is one who you could sweet talk into getting it drawn up for you.


----------



## pvd (Jan 4, 2006)

Why not just make an adapter manually in 30 minutes out of scrap stock?

You still need to make a print, but by no means do you need to CNC or solid model anything.

This kind of sh!t is super F#cking simple.


----------



## Sim2u (Nov 22, 2006)

I think with a dremel and various attachments, a power drill and various sizes, a saw and files with a bench grinder, you could very well make this easy...albiet with less finesse and minus the more subtle aesthetic treatment. So i think PVD is correct in that regard...go on, give it a go, most chaps have all that stuff at home anyway.


----------



## patineto (Oct 28, 2005)

Just for FYI porpuse, since is some how cost prohibitive for just a individual.

The other day I got a demonstration from this guys at *protopulsion* to see if i will be interested in implement (Buy, lease, contract) their services and/or purchase machines for my company..

They can pretty much do anything, from scanning even the most complex 3D shapes to make extremely accurate "Models" out of any solidworks file.

Pretty Impressive, Not cheap but pretty impressive none the less


----------



## surfthedrum13 (Jun 17, 2008)

Go to the largest college in your area (with engineering if you can maybe a big tech. school) and see if you can't find a student that needs some extra cash..

I can scan and make a CAD/CAM model for free and use the CNC's if I have my own material at school. So if your able to find a student give him the part, material, and some $ and you can get a part. I doubt anyone that works at the college can make the part for your for cheaper if they can at all.


----------



## ScaryJerry (Jan 12, 2004)

Seriously, every county has a local vocational school full of machine tool tech students that need a semester project to crap out. (Note: They love beer)


----------

