# Recommendations requested: A suitable machine shop to make a single small part



## couver52 (Dec 7, 2015)

I just need a slightly modified remake of an existing threaded bezel. Background: I have one of those 85 Watt eBay HID flashlights. Since it works well as far as the electronics are concerned, but not so the reflector, I decided to replace the factory reflector with a better one. The better reflector has the same terminal diameter, fitting nicely into the aluminum factory bezel just like the original reflector. However the new reflector is deeper than the factory one, meaning that it sticks out further, and thus in order to enclose it properly what I need is a lengthened, while otherwise exactly the same, remake of the original bezel. I've learned from past experience that not all machine shops are approachable when all you have for them to do is a single and out-of-the-mainstream small job, with no potential for lots more work to follow afterwards (as might be the case, say, if I were an entrepreneur wanting a sample of their workmanship before ordering in quantity). Thus I'm asking for recommendations in the hope of expediting my search for a shop that'll be friendly towards my flashlight-hobby related need here. I'm in the Vancouver, BC area. But the part is light and small, so location/distance is less of a consideration than finding a suitable shop I can affordably entrust to do such a little job in earnest.


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## precisionworks (Dec 7, 2015)

couver52 said:


> I just need a slightly modified remake of an existing threaded bezel. ...


Please don't be offended when I say this but whenever someone says:

I have an easy job for you
I have a small job that shouldn't take much time
I just need you to duplicate this part
Etc, etc,
It often means that the customer doesn't realize what's involved. I've lost hundreds, probably thousands of dollars on these "simple" jobs. 

That said, you need to draw up an accurate 2D sketch of the new part. Three views, dimensioned, with all tolerances called out. That alone will make it more likely that someone will at least quote the part. You don't need AutoCAD, just download Google SketchUp & make the drawing. It might take an hour the first time, maybe more depending on the complexity of the part, but there are few shops in the world that will quote without a print.

Once you get the print done, post it here & someone may be able to make it for you. 

https://www.google.com/search?q=google+sketchup&ie=utf-8&oe=utf-8#q=google+sketchup+2d


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## gadget_lover (Dec 7, 2015)

Like he said, no offense meant but more info would make a great difference.

It's not possible to determine what needs to be made /done from the description (ebay HID).

My suggestion; Eventually you will find someone who can do this for you. That person will need pictures or drawings as well as a description of the part. The pictures will need some scale (like a ruler ) to give a sense of scale.

You might as well put that information together and post it now. Then you can print it out if necessary to hand to a prospective machine shop.

It sounds like you may need a new bezel, or you might just need a collar with male and female threads to move the existing bezel out a bit.

Dan


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## couver52 (Dec 7, 2015)

precisionworks said:


> Please don't be offended when I say this but whenever someone says:
> 
> I have an easy job for you
> I have a small job that shouldn't take much time
> ...



Yes. I totally get it. I was aware of the advantages of drafting an accurate 2D sketch. But only now am I aware that providing such is always an essential. Thanks for pointing this out and also pointing me to SketchUp as a program suitable for someone like me to utilize to facilitate the process. 

As an aside, for a very long time I've thought, if only I had the training needed to make affordable use of AutoCAD (second only to owning -along with having learned a mastery of same- my own CNC milling machine, lathe, etc). Glad to know I don't have to be that advanced before I can submit build data here in a technically acceptable format. When I've got this 2D sketch done I'll post it here for constructive criticism on it before deciding on a final sketch that's suitable to send to a machine shop.

Thx...


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## couver52 (Dec 7, 2015)

Agreed. The more useful information I can include (in the appropriate way) the better. So pictures with appropriately placed rulers and such will be included along with the drafted sketches.

Yes, a new and longer bezel is what I'm after. I've also thought about having a collar made instead (with male and female threads) to insert below the bezel. And giving it second thought just now, latter may be more straightforward for the machinist to make than a new but longer bezel, since the bezel requires the forming of a mildly intricate looking lip, within which there is a barely perceptibly small groove that a very thin o-ring must be inserted into; and this o-ring, which in addition to sealing out reflector-damaging humidity, is the surface that, when tightening the bezel, clamps down on the lens which in turn clamps down on the reflector rim just beneath it, keeping both inside as well as preventing the slightest untoward movement of either.


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## unterhausen (Dec 9, 2015)

I had to look at the date, this comes up on a regular basis and the answers are always the same.

I have a friend that always insists on pictures when I have a technical question. Of course he never sends me pictures when he wants something from me.

I'm a particularly visual person. You always need a sketch though. When I design something, a lot of times I'll have an idea and then when I put it into cad I don't like the way it looks.


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## precisionworks (Dec 9, 2015)

unterhausen said:


> I had to look at the date, this comes up on a regular basis and the answers are always the same.



"It's like déjà vu all over again." :nana::nana::nana:


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## couver52 (Dec 17, 2015)

*precisionworks
* 

"Originally Posted by *unterhausen* 

 'I had to look at the date, this comes up on a regular basis and the answers are always the same.'


"It's like déjà vu all over again." 

Sorry you guys. I spent a lot of time searching for and going over previous posts related to this topic. I didn't see any that asked the same questions that I have asked here. Not too say these questions have not been asked before. But I could spend the rest of my life searching, trying out various key terms, search parameters and filters, not to mention scanning through the mass of mostly not quite relevant enough returns, without finding the basic information one is looking for. At some point it makes sense, ego notwithstanding, to just stop and ask somebody. 

Also, about those sketches (with photos) I promised I would post here... I have the photos ready to go. But as far as sketching is going, well I haven't made that a priority yet. Last time I ever drafted anything was 42 years ago. I was then in 7th grade and Industrial Ed. class we were introduced to drafting, in what is now the obsolete way; with t-squares, three-sided rulers, french curves, and the like. Now there's SketchUp... I just want to do some simple 2D drafting over a graph paper drawing background. But no, I have to attentively sit still and absorb I don't know how many hours of video tutorials which so far emphasize 3D more than anything else before getting to where I can learn how to get to the 2D drafting. And just playing around with the different tools I haven't managed to find any intuitive shortcuts to speed me on my way to using it. And in the mean time, while I've been taking pictures of the inside and outside of the flashlight in various stages of disassembly as well as a whole, which I will post to an image server shortly, alongside appropriate measurement tools (e.g. rulers, digital calipers, etc.) new considerations have occurred to my mind which I must address in my upcoming sketches (e.g. providing a good contact surface for cradling and aligning the reflector, whilst ensuring adequate heat conduction/dissipation from the reflector itself into the outer fin-cooled body of the flashlight). Workable ideas are now finally beginning to occur to me, which I will soon integrate into in the sketches soon to be posted to an image service as well..


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## precisionworks (Dec 18, 2015)

A drawing on gridded graph paper is always acceptable. 2D programs were suggested because that is what the majority of people like to use today & because they are easy to save as a PDF file and email to a machine shop.


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## gadget_lover (Dec 18, 2015)

couver52 said:


> ...while I've been taking pictures of the inside and outside of the flashlight in various stages of disassembly as well as a whole, which I will post to an image server shortly, alongside appropriate measurement tools (e.g. rulers, digital calipers, etc.) new considerations have occurred to my mind which I must address in my upcoming sketches (e.g. providing a good contact surface for cradling and aligning the reflector, whilst ensuring adequate heat conduction/dissipation from the reflector itself into the outer fin-cooled body of the flashlight). Workable ideas are now finally beginning to occur to me, which I will soon integrate into in the sketches soon to be posted to an image service as well..



That's one of the beauties of taking the time to document what you want. You begin to discover things that are important to the design. I've known people who spent large sums of money on prototype after prototype because each model uncovered some new detail that the previous one had not. Drawings are a 2D prototype.

Daniel


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## DrafterDan (Dec 20, 2015)

Then, C52, you already have a leg up with drafting classes. When I went to college for architectural drafting, it was pencil & paper. Only later classes were with AutoCAD. 1986, I think? I've barely done any 3d drafting, actually. My work doesn't need it


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## couver52 (Dec 28, 2015)

Yes, I recall it was the early 80s when I first read mention of CAD (except back only in association with its factory-floor counterpart, CAM) as "CAD/CAM technology".


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## NoNotAgain (Dec 28, 2015)

gadget_lover said:


> That's one of the beauties of taking the time to document what you want. You begin to discover things that are important to the design. I've known people who spent large sums of money on prototype after prototype because each model uncovered some new detail that the previous one had not. Drawings are a 2D prototype.
> 
> Daniel



That's the beauty of Autocad Inventor. You can stack all of your assemblies on top of one another and run them to verify the interfaces without actually having to cut chips. 

Most shops around me won't accept anything but Autocad or Solid Works models. A simple part may take a couple of hours of computer time before a chip gets cut. Few shops want to run manual milling machines because tech schools teach button pushers not machining. Real machinists are a dying breed. People don't want to learn trig.


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## couver52 (Dec 29, 2015)

You said, "Most shops around me won't accept anything but Autocad or Solid Works models." I'm glad you're telling me this. Not that this is favorable to me and the limited amount of time and personal energy I have to spare, not to mention my software budget. But it's confirmation of my hunch as to why I cannot seem to find a single simple trade-wide drafting reference I can use in determining how to start so as to properly finish my sketches here.

This hunch has actually has already lead me to download and install AutoCAD 30-day trial, along with a plethora of other CAD software free-trial downloads, due to a desire to find something having a less demanding learning curve and/or something I can afford to buy and therefore not be constrained to have to speed-learn in time to begin putting to actual use a free-trial. I was about to settle on the idea of investing in CorelCAD, since, for one it's very cheap, and two, long having and enjoying Corel PaintShop Pro (and, though in the past, also Corel Draw) I've wanted a reason to expand to a full suite of Corel graphics creation and editing applications.

But based on what you have said, I will now have to rethink this again.


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## precisionworks (Dec 29, 2015)

NoNotAgain said:


> ... Most shops around me won't accept anything but Autocad or Solid Works models.



It depends.

I receive quite a few RFQ's, some are real jobs about to happen & some are dreams that may never happen. "Prints" (mostly emailed but sometimes FAXed) are sometimes hand drawn but mostly done with a 2D CAD program as most of the parts I quote are simple enough. However, if a customer who I believe is sincere submits a drawing on a paper napkin then I'll take the time to redraw it in StoneAgeCAD (aka DesignSpark Mechanical) & send the DSM drawing out for quotes. 

Some of the RFQ's I receive have call outs without tolerances, conflicting dimensions, materials that aren't specified, etc. I go back and forth between the customer & the machine shops & iron out all the details. Sometimes, more often than not, I get a decent paycheck at the end of the day ... which may be six months after the RFQ hit my shop. During which time I work for free without any guarantee of payment. 

Will an AutoCAD or SolidWorks model get your project looked at? It certainly doesn't hurt. But unless a shop stands to make serious money they may politely refuse to quote (aka No Quote). I'm fortunate to work with a handful of high end shops & they are beyond busy. Fastest current lead time is 30 days ARO, average lead time is 60 days & the longest lead is 90 days. None of these shops will even consider a job unless they can make a few thousand dollars & that's the greatest hurdle with a one-off or a small run job - the profit just isn't there.

Look around for a community college with a machining or industrial manufacturing class & enroll as a non-credit student. Some classes are during the day, others are in the evening & you may find something that works for you. I've had a few students enroll as non-credit simply because they are able to use the lathe or mill (or CNC mill) for not much money (varies widely so check around). My non-credit students, after demonstrating sufficient knowledge, are primarily self-directed - which is an academic way of saying they develop their own machining prints & build about any part they want to build (excluding firearms or components). 

What's the fast track for learning AutoCAD? IMHO it's a CAD class at a community college. Autodesk (designer of AutoCAD & Inventor) is very active in the educational community & issues free licenses to insitiutions, teachers & students. Then it's a (relatively) easy transition to export the .dwg file to MasterCAM & plot tool paths, etc.


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## couver52 (Jan 2, 2016)

Over the last two weeks I've downloaded and installed several fully functioning CAD software free-trials, including AutoCAD, AutoCAD LT, Graphite and CorelCAD. Graphite and CorelCAD are light CAD, yet not light enough for me to learn as quickly as to my liking. AutoCAD is for me at the moment an enigma of a software program as far as how/where to begin anything. But now that you've advised me about simply enrolling in an AutoCAD course, at a community college, I realize that will also give me free access to use AutoCAD at home while enrolled and possibly an affordable price I might choose to buy a permanent license for it, though I'm not certain. So enrollng in an AutoCAD course at a local community college is exactly what I'm going to do; even if I'm not able to get a seat in time before I find some other way to finish off this project. (E.g. just an idea but maybe get a hold of some ABS "bar stock" -if there is such a thing; if not there are tutorials explaining how to make liquid ABS which can then be poured to later harden into something close to the desired shape and dimensions, and which can then be hollowed out, shaped, surface finished, potentially even threaded [I'm not sure though] on a wood lathe. Of course there are also other plastic materials and kits available which may be even more suited to this). Round aluminum tube or round aluminum hollow bar stock appears to be unlikely here due to the standard outside diameters these come made in being either way too small or way too big. The different wall thicknesses available only affect inside diameter, never the outside diameter. There the 3 inch diameter size which appears just a disappointing tad too shy of the inside threaded diameter of the flashlight part which this would need to first be threaded on the outside in order to mate with that inside thread I just mentioned. Admittedly I will have to revisit this using a vernier micrometer -as opposed to my current cheap digital caliper- and all much the more precise measurements the micrometer will provide me with, written down on paper in hand to compare, calculate, etc... before I can positively know this for sure. 
Anyways, being free from my all-consuming work schedule to attend a community college course is a little ways away. While I certainly would much prefer to get my flashlight parts drawn up and posted as I was invited to do here, before my current motivation and my 'obsessive' interest in this project loses its steam. So I'm just going to go for it to just try to get these drawings made some way somehow, whether on vellum or raster, and whichever it is, to the best of my present technical understanding and practical judgement, and hope it flies. 

Thx

PS: And the pictures too, of course. I haven't forgotten.


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## DrafterDan (Jan 2, 2016)

ACAD has a steep learning curve. I'm currently using ACAD LT 2011, which works fine for my needs. There are tons of help sites (forums and youtube), and ACAD help itself is pretty thorough.

Strangely, I've used it so long that a lot of the commands and keyboard shortcuts are part of my thought process. I don't really think about how to do something, I just draw. I hope that didn't sound like bragging, I just use it a lot.

Another process is metal 3D printing. I understand they are able to do aluminum now. I wonder how printed threads would turn out.


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## couver52 (Jan 4, 2016)

I'm sure that once I get going on it, I too will find AutoCAD not so hard. It's not as though I think it's something that should be difficult for me to learn. But it's analogous to going to the gym to get in shape. Actually doing the exercises and all is not all that hard. It's just making the decision to get there, that's hard. It's kind of the same thing with regard to having to learn any of these CAD programs before I can use them. Once I've committed to start the learning process, I'll be fine. But since it probably will take a while to get to the point where I can use a CAD software to be of possible help to me in the simple sketches I need to make for this very simple project, this project by itself just isn't enough of a source of motivation for me to begin this process just right now. 

Note I mention, "possible help to me in the simple sketches". It is my uncertainty as to what else is required in these sketches, besides the simple drawings (done to scale) with all the necessary dimensions shown along with their exact numerical measurements written, that in part at least, contributes to my delay in getting these done. (The other cause of delay is the fact that I have to determine the exact coordinates of the reflector when it is in perfect focus, in order to be able to prescribe the length of the extension piece to be made.) When I Google image search for other such sketches, I see drawings which are not marked exactly as what occurs to me as logical to do, reminding me that this isn't just drawing, its a language. And being a language, there's got to be conventions, systems of reference, and symbols to use which I'm in the dark about. Also with the art of drafting having been swallowed up by various proprietary CAD software, I cannot just get a generic drafting reference book, like I might have 35 years ago. Maybe I will just have to learn AutoCAD before I can have my parts made for me, after all.

Regarding your reference to 3D printing, whether your referring to the low-end or Desktop 3D printing (around $3,000 for a machine) or enterprise level 3D printing (upwards of $100,000 for a machine), you still have to use some form of CAD from which to input the digital instructions the machine needs to print anything.


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## couver52 (Jan 5, 2016)

precisionworks said:


> A drawing on gridded graph paper is always acceptable. 2D programs were suggested because that is what the majority of people like to use today & because they are easy to save as a PDF file and email to a machine shop.



I've finally found one CAD program (Power Draw 3.0) that is essentially old fashioned drafting on a grid paper like interface, except in place of a compass, shape templates, a T-square and protractors, etc, the software provides for all these functions. This CAD program is freeware and therefore as can only be expected of such it has its failings. But at least it allows me to begin drawing something simple right away (without resorting to the more familiar, but obsolete, drafting table/desk and implements for which I would have readily turned to by now, except for lack of space).


[prior edit entry, deleted]


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## DrafterDan (Jan 7, 2016)

I've not heard of that one, but if it does what you need, then great!

You'll have to show us some of your drawings when complete, I'd like to see how the end result looks

~D


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## couver52 (Jan 11, 2016)

To see my first sketch, please go to: www.flickr.com/photos/[email protected]/24230089641/in/dateposted-public/ . It's not complete, as the other drawing which should be there too, representing the view from the other spatial dimension, is still needed. (Also there is a second component for which the sketch is still to come as well.) Let me point out that I ended up primarily using my PaintShop Pro, a general bitmap-based photo editing program, to draw this. Anyway, a bit of description: This sketch is of the flashlight extension tube as viewed from the side. I've tried to include in the sketch not merely the outside surfaces, but also the inside surfaces. Also, I may have gotten a little carried away in visually portraying the threaded portions. I hope it's self explanatory enough. I'm sure there are commonly understood conventions for representing such details which would make this drawing more intelligible to someone in a machine shop. But I've decided I can either keep drawing nothing while I seek a better grasp of CAD, etc, or I can wing it in the interim. Constructive criticism is requested. Thank you.

CR52

PS: I know that the 0.08 inch wall thickness is far too slim to be viable. And I do not really think the allowance I entered for cutting of the threads should make any sense either. I will be deciding on some real figures to use there. But it's late and I'm tired, so this will have to be done later.


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## gadget_lover (Jan 11, 2016)

I have to agree. You have to start somewhere. When I plan to make a part, I draw it up on paper, typically on whatever is handy. 

Looking at your drawing, it gives a good idea of what you are making, once I get it in perspective. I thought at first that it was a flashlight on end. 

It will help you to learn a few terms used to describe threads. First I have to digress a little to provide background. There are certain standard screw threads defined by a standard ( a 1/2 inch diameter , 13 TPI bolt for instance). In addition to the pre-defined threads, any diameter can be used with any TPI as long as the thread profile matches the standard. The standard defines the RATIO of the thread depth to the pitch. It defines the shape of the thread as using 60 degree sides with flat bottoms (root) and crests (top). The standard also includes "class of fit", which is how tightly the threads fit together. The same thread profile is used for Metric and imperial threads. 

To specify threads, you will want to familiarize yourself with the terms root, crest, pitch, major diameter, minor diameter, pitch diameter, Thread height and TPI. I tend to refer to a picture when I need to visualize it. All of this is well documented as the Unified Thread Standard. ( https://en.wikipedia.org/wiki/Unified_Thread_Standard )







Daniel


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## couver52 (Jan 13, 2016)

Much thanks, gadgetlover, for the info and reference I need in order to include a proper description of the threads. 

I was just thinking about my need to know all the parameters of the threads for which a machine shop would need to have complete values; considering how important it is that the newly machined part threads align with the existing threads, and which will hinge entirely on on the accuracy and readability of data I provide, alone. Back and forth shipping over a long distances for trial-and-error correction work, just won't be a practical option which I intend to never make necessary.

CR52


PS: This morning I pulled out my thread gauge (which I bought used off of eBay ages ago for such a time as this) to realize it's only handy for getting the TPI; the one measure I could have gotten easily enough by just counting (with the aid of a ruler and magnifying glass). Oh well, at least I hadn't paid much for it.


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## couver52 (Jan 13, 2016)

For those interested in my previous mention of trying out the free CAD program, PowerDraw... PowerDraw hasn't been all that helpful so far. It seems just not require much to learn because there isn't much functionality in the program. (This is just my feeling. I haven't tried it out in earnest yet.) But I've found another another free 2D CAD program; this one is a full commercial CAD application put out by the SolidWorks people; that is, it's free for non-professionals such as hobbyists, etc, to use. (If you as an individual use it for anything to earn money at, then you will have to pay approx. $500 for a perpetual license.) As 2D CAD that is purported to be as feature rich as any premium 2D CAD program. I've begun playing with it just to get a intuitive sense of what I can do with it. Finally I think I may have found a CAD program suited both to my purposes and my humble starting-knowledge level. I'll see how I progress with it once I begin viewing the tutorials available for it. I have the sense that this program's tutorials will not present me with a challenge to remain 'fully awake and motivated' such as I experienced with other CAD/Drawing programs and the tutorials I had looked at earlier.

CR52


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## gadget_lover (Jan 14, 2016)

couver52 said:


> PS: This morning I pulled out my thread gauge (which I bought used off of eBay ages ago for such a time as this) to realize it's only handy for getting the TPI; the one measure I could have gotten easily enough by just counting (with the aid of a ruler and magnifying glass). Oh well, at least I hadn't paid much for it.



A thread gage is a very handy thing to have. If you use a magnifying glass you can ensure that the thread matches exactly. You can have a 12 TPI thread that is very poorly formed ( I.E. made with worn out tools. Some If you look at the threads on all of your flashlights you are guaranteed to find some that are only vaguely similar to the UN / ISO profile. 

The dimensions of the the root of a male thread and the crest are easy to get using a caliper. If the root and crest are reasonably flat you can use them for the major and minor. Make sure that you design it so that the crest of the thread does not bottom out on the mating root surface. 

If the roots and crests are poorly formed (I often see sharp peaks on cheap lights, for instance) you may need to buy thread wires to measure the width of the center of the groove. They only cost a few bucks from online dealers. The dimensions can be mathematically determined from that. Thread wires only work if the thread uses a proper 60 degree angle. 

Dan


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