Author Topic: Blue Plastic Nuts For Wood Self Fabricated (Read 6788 times)

Pawel66 · « **on:** January 30, 2021, 15:13:13 »

We have fabricated some of the blue plastic nuts for dash wood holding. I think they are ok - at least I am quite happy with the result.
Mrfatboy prepared an excellent file for 3D printing based on wwheeler's drawing and a sample/picture of original from Joe and Alfred. So what I had to do is just to print and thread them.

The nut has 5mm orifice not threaded down to 4.5mm form the knurled top. Then the orifice diameter narrows to 4mm for M5x0.8mm threading. That is how the 3D file was made by mrfatboy - as it should have been. I just found it useful to drill a bit the 5mm part again with a drill bit, to widen it slightly.

Getting tightness right on a screw after threading needed experimenting - not to have them too tight and rip off the studs from the wood and not too lose so that they do not unscrew themselves on their own. I tried leaving part of the orifice at the coned end not threaded (like in the modern self-locking nuts) but then the nut was far too tight.

So I followed Alfred's advise on using the 3 staged taps. When I went through all 3 stages - the nut was too lose. When I stopped at stage 2 (intermediate) the tightness was just about right in my opinion, so that is where I left it. Best is to do some trials on your prints and studs if you want to fabricate these nuts.

Thanks everyone for help!

wwheeler · « **Reply #1 on:** January 30, 2021, 16:25:44 »

Good news! Looks really nice. The color looks pretty close to me. Sure, other plastic nuts may work. But you will feel much better when driving your car knowing that you have the correct nuts holding down the wood.

The other option for the 3 stage tap system are taps meant for plastic. I know McMaster sells one that “ejects” the material forward so that it doesn’t get run back through the threads. Supposedly creates tighter threads. https://www.mcmaster.com/2673A74/

Pawell, have you tried using a wrench on the nut? I think it was a 9mm wrench that was required. I wanted to check how the fit was.

The next question is....how can we get our hands on these?

Pawel66 · « **Reply #2 on:** January 30, 2021, 16:49:26 »

Wallace, yes, mrfatboy prompted me to check it - 9mm socket/spanner fit nicely.

mrfatboy · « **Reply #3 on:** January 30, 2021, 16:53:48 »

I will put the 3D file in the tech manual later today. You can just download it and print them yourself.

wwheeler · « **Reply #4 on:** January 30, 2021, 18:01:39 »

Thanks!

mrfatboy · « **Reply #5 on:** January 30, 2021, 18:45:52 »

The 3D file (.stl) of the Blue nut has been uploaded to the Tech Manual.

https://www.sl113.org/wiki/Restricted/TemplatesDecals

wwheeler · « **Reply #6 on:** January 31, 2021, 00:13:21 »

To help us (me really) that are Hi tech challenged, What do I need to send to a 3D printer? The file in the tech manual is a .stl. I have that copied and is that what I send?

If I go to menu and click on "save as", it gives me options of a image, 3D image and then a video.

Thanks!

mrfatboy · « **Reply #7 on:** January 31, 2021, 00:19:50 »

Yes. Just download the file and send to printer.

I don’t think it matters what file type you select but make sure you get “Blue Nut.stl”

I have not actually done it but maybe Pawel can share his experience and let us know some details.

I think there are some online companies that print also. Check around for pricing.

mrfatboy · « **Reply #8 on:** January 31, 2021, 01:02:54 »

I just downloaded the file to my iPhone and viewed it with this free app. Just search for “free stl viewer”. I’m sure there are similar apps for Android.

Once loaded in the app you can zoom and spin the nut around its axis.

Try it

https://apps.apple.com/us/app/stl-simple-viewer/id1493598400

Pawel66 · « **Reply #9 on:** January 31, 2021, 01:17:47 »

As mrfatboy says, just download it, save it as .stl (would be probably a 3D image suggestion, just make sure the file is .stl type).

Find a 3D printer near your place in Google, or not necessarily near your place. Send them an e-mail or call them asking if they can print for you in blue colour. Send them the file you saved by e-mail and ask to ship the nuts to you. If they are near your place, you can go to them and check what they printed.

So: download, save as .stl file type, send by e-mail to the printer. That is all.

Print more than you need, just in case.

col320ce · « **Reply #10 on:** January 31, 2021, 03:35:40 »

This is fantastic...

wwheeler · « **Reply #11 on:** January 31, 2021, 04:05:07 »

Ok thanks. I feel empowered!

wwheeler · « **Reply #12 on:** February 10, 2021, 00:29:16 »

I contacted a local 3D printer and he produced one as a prototype. See attached. Pawell, how do you think the texture compares with what you made? Not sure it is going to get much better, but I can see. What material did your guy use?

I am thinking that I might get more than I need and can sell the remainder to other US members here if there is any interest. The nut is not threaded, but I can do that and send it on. I do not have a finalized price but possibly $2/each plus US shipping. To ship outside the US would be cost prohibitive.

Thanks.

mrfatboy · « **Reply #13 on:** February 10, 2021, 00:38:28 »

I have seen several videos on how different printers work and even using acetone gas to smooth out the texture in one instance. That seems more of a hack than anything but it sorta worked.

I think it comes down to the quality and type of the printer used. I saw a resin 3D printer that had amazing detail. Again, I know next to nothing about 3D printing. 🤪

mrfatboy · « **Reply #14 on:** February 10, 2021, 00:54:05 »

Wallace,

Does your blue nut have a slight arch at the top of each side of the hex nut? I can’t see it in your picture but I see it in Pawel’s. Maybe just a bad angle of picture.

wwheeler · « **Reply #15 on:** February 10, 2021, 01:07:15 »

I looked on his 3d sketch and no it doesn't. Good catch! I will see about getting that fixed.

Thanks.

wwheeler · « **Reply #16 on:** February 10, 2021, 01:43:58 »

I just figured out how it happened. My printer added a hex on top of the nut in place of the circle. The hex allowed the distance from the point along the angle to be the same as the distance to the flat. Therefore no arch. To get the arch there has to be a circle on top just slightly larger than the bore. Hopefully he can fix that.

mrfatboy · « **Reply #17 on:** February 10, 2021, 02:48:54 »

Why did he even change the file? I thought he just prints what’s given to him. Again, I’m note familiar with the printing steps.

wwheeler · « **Reply #18 on:** February 10, 2021, 04:13:46 »

He said that the file had some glitch and he had to "fix" it. My guess is substituting the hex instead of the circle was the fix. But I am checking. I went back and looked at the print I gave you and I left off the angle dimension on the top. Not sure if that had anything to do with it. I am even further away from CAD and 3D printing than you, so I am no judge. Hopefully he can get it right.

mrfatboy · « **Reply #19 on:** February 10, 2021, 04:18:57 »

Your drawing didn’t have the arch. I added it after I saw a real one that Alfred brought over.

I don’t know about glitch. Pawel’ printing worked. I think there is a”software” factor🤷‍♂️

Pawel66 · « **Reply #20 on:** February 10, 2021, 07:35:11 »

Attaching pictures again - mine do have the arch. The texture is, I think somewhat similar. The cost here was ca $1.7 per piece.

wwheeler · « **Reply #21 on:** February 10, 2021, 16:04:31 »

Quote from: mrfatboy on February 10, 2021, 04:18:57

Your drawing didn’t have the arch. I added it after I saw a real one that Alfred brought over.

I don’t know about glitch. Pawel’ printing worked. I think there is a”software” factor🤷‍♂️

I left that feature off because it would have been too difficult for me to calculate. But if you have the circle on top and the flat angle going down, the arch appears automatically by geometry because of the different distances to the edges. That took me a while to get. My 3D printer changed the circle to a hex which allowed the flat as opposed to the arch. Hopefully I will find out why today.

mrfatboy · « **Reply #22 on:** February 10, 2021, 16:16:26 »

What software are you using? I have seen several free ones out there that people seem to like. However, I can’t remember their names. I’m sure you can google for the list.

wwheeler · « **Reply #23 on:** February 10, 2021, 17:07:22 »

I sent the company the STL file, "Blue Nut", and they took it from there. The drawing he sent back says Autodesk fusion 360. That is about the extent of my techie ability.

olhughes · « **Reply #24 on:** February 11, 2021, 00:52:13 »

I do 3d printing and the .stl file must be sliced to create a .gcode file that the printer understands. I have 2 printers and each uses a different .gcode file. when I first sliced the .stl file it told me that there were errors with the file and if ignored and printed anyway I ended up with a nut without a center hole. pulling it into a different drawing file then slicing I get a hole from the top down just shy of the base. Waiting on the blue filament so I can print them in the correct color. Once I print, I will probably print a bunch so if others need them...

mrfatboy · « **Reply #25 on:** February 11, 2021, 01:01:30 »

On the second version with the hole, is the hole the same diameter all the way through? I actually designed the hole to be 4mm in diameter about half way down from the top so it can be tapped to 5mm. The rest of the hole is 5mm in diameter the rest down with no threads like original.

neelyrc · « **Reply #26 on:** February 11, 2021, 03:17:36 »

Chip, thanks for chipping in on this topic (of course pun intended!). The collaboration in the development of this small part by a group of members with varying skill sets is a testament to the strength of the group.

I also look forward to seeing you share your MB and particularly113 knowledge and experience on other topics.

Pawel66 · « **Reply #27 on:** February 11, 2021, 07:35:12 »

Quote from: mrfatboy on February 11, 2021, 01:01:30

On the second version with the hole, is the hole the same diameter all the way through? I actually designed the hole to be 4mm in diameter about half way down from the top so it can be tapped to 5mm. The rest of the hole is 5mm in diameter the rest down with no threads like original.

It may not be seen on the pictures, but this is how it printed - 5mm half way down, then 4mm for threading.

wwheeler · « **Reply #28 on:** February 11, 2021, 21:53:23 »

Chip,

I have a question about material since you are an accomplished 3D printer. My local printer was wanting to use PLA because of cost, availability and good color selection. I looked that up and the main concern with that material is higher temps. But also said it is vegetable based and is biodegradable! I don't think that is a good option for this nut that is well hidden under the dash. No one wants to replace it again once it is installed.

He is considering using ABS which I think is a far better material for this application. What do you think?

Wallace

doitwright · « **Reply #29 on:** February 16, 2021, 18:19:23 »

Don’t have a 3D printer? Check https://oldtimer-ersatzteile24.de/Knurled-nut-for-trim-strips-blue-D-15x85-thread-M4

Pawel66 · « **Reply #30 on:** February 16, 2021, 18:45:35 »

I saved EUR 70!

Gewinde M4? we did M5....

mrfatboy · « **Reply #31 on:** February 16, 2021, 18:56:48 »

The hole was made to 4mm. You need to tap it to 5mm. The nut is 9mm. I believe Wallace even verified the original fits a 5mm stud.

66andBlue · « **Reply #32 on:** February 16, 2021, 19:24:43 »

M5; see: https://www.sl113.org/forums/index.php?topic=32460.msg236316
Replies #19 + 20

Pawel66 · « **Reply #33 on:** February 16, 2021, 21:48:06 »

Yes, yes. They made a mistake. In description or in the nut.

wwheeler · « **Reply #34 on:** February 16, 2021, 22:25:03 »

I think the nut shown on the Oldtimer site is the shorter 4mm dash nut as used on the W111/W110 Sedans. Gewinde M4 translates to 4MM thread. Joe pointed out earlier that the sedans use a different nut (4mm) than does the Pagoda or the W111 coupes and cabs which is absolutely a 5mm thread.

Some confusion may have a risen because we chose not to print the threads for quality reasons. The ID hole was left at 4mm and needs to be finished out to make the correct 5mm thread.

Clear as mud?

Pawel66 · « **Reply #35 on:** February 16, 2021, 22:29:25 »

ok, I see, thank you.

It is a nut for sedans for different application. The description was clear. They made a nut for sedans and they put it in W113 section too. It is a product placement mistake - nut for trim strips. Different nut from different fairytale.

mrfatboy · « **Reply #36 on:** February 16, 2021, 23:40:19 »

Yes. Smaller one has 4mm threads.

wwheeler · « **Reply #37 on:** February 17, 2021, 04:02:05 »

Much ado about nuts.

mrfatboy · « **Reply #38 on:** February 17, 2021, 04:13:20 »

Fun fact. Those are actually 66nblue’s nuts. 🤣🤣🤣🤣🤣.

wwheeler · « **Reply #39 on:** February 17, 2021, 17:07:20 »

Nice!

66andBlue · « **Reply #40 on:** February 17, 2021, 18:58:46 »

Quote from: mrfatboy on February 17, 2021, 04:13:20

Fun fact. Those are actually 66nblue’s nuts. 🤣🤣🤣🤣🤣.

Mardi Gras is over and the Fatboy is still nuts!

When will it end? 🙄

wwheeler · « **Reply #41 on:** February 27, 2021, 00:15:40 »

FREE PARTS: I have (30) spare blue plastic nuts and obviously don't need that many. Like Pawell's, they are not as smooth as a molded part but function just fine and have the blue color. These were printed using the STL file from mrfatboy. They need to be tapped and can be done so very easily with a 5mm tap. Also there is a plug in the hollow end that was used to support the nut during printing and it chips away easily.

I will ship these in lots of (5) to whomever is interested for FREE if you pay shipping (US only). Attached are pics. I will have to get a quote, But I imagine shipping would be no more than $5.

PM me if you are interested.

Charles 230SL · « **Reply #42 on:** February 27, 2021, 00:31:01 »

hello Wallace, PM sent,, vr, Charles

mrfatboy · « **Reply #43 on:** February 27, 2021, 00:34:55 »

That’s better than white ones at $8 a piece plus shipping🤣🤣🤣👍👍👍

If you have a little OCD I bet you could clean them up with some 600 grit sand paper 🤣

There are different types of 3D printers out there. I have seen “Resin” types that would print a much cleaner version. I have no idea of cost

All in all. Good job👍

wwheeler · « **Reply #44 on:** February 27, 2021, 00:50:50 »

BTW, these are ABS material and yes could smooth out with just about any solvent. ABS solvent melts very easily. The first material my 3D printer wanted to use was PLA which is a vegetable based material and biodegrades. It is cheap, plentiful with loads of colors. I don't trust that PLA will last under the dash for 20+ years without falling apart. Not worth the risk to me. So I made sure it was ABS.

mrfatboy · « **Reply #45 on:** February 27, 2021, 01:01:58 »

Is PLA the same as resin? I know JonB and I had our vintage battery caps made out of ABS for the reasons you stated.

I saw a video in which a guy bathed the printed item in a acetone vapor bath for ~30 seconds. Timing was critical. Too long and it melted away🤣

The guy poured a little acetone on a plate. Put the printed item on a raised platform on the plate so the item would not touch the acetone. Then he covered it was a clear glass so that that vapor flowed around the item. Watch and pull it out before it totally melts. 😜

wwheeler · « **Reply #46 on:** February 27, 2021, 01:35:20 »

I know much more about rubber than I do plastic. But you approach them the same way in that you have to know the pros and cons for each and match that to your application. There is no perfect material.

PLA was a new one for me and not sure if it resin. Seems like there are a few different methods used for printing. This is all new to me as well.

I have worked with ABS before and not surprised that acetone vapor will effect it. Solvent welding is the primary way to repair ABS. Just melt, clamp and let vapors evaporate.

wwheeler · « **Reply #47 on:** February 27, 2021, 04:49:04 »

I just compared the thread feel of the original blue nut, the white Mercedes replacement nut (#000 990 06 50) and the 3D printed nuts I have. Interestingly, both Mercedes-made nuts have a light self locking feature as the screw nears the top. If you run a tap straight through a 3D printed nut as I did, there is no locking feature and the thread feel is uniform throughout.

So I am going to experiment and use a tapered tap but not run it all the way through. But rather stop at some point before the threads are completely cleaned up. That should result in a "self locking" feature just at the top.

Pawel66 · « **Reply #48 on:** February 27, 2021, 19:58:47 »

Wallace, in a highly unlikely event of failing to create the self-locking lip doing the way you described, here is alternative I exercised:
- screw in the screw into the nut in such a way that the tip of the screw is still hidden in the threaded part of nut by, say, 0.5mm
- heat up the tip of the nut
- press it against something

The more distance you leave between the edge of the nut and the tip of the screw, the higher self locking force you will receive.

wwheeler · « **Reply #49 on:** February 27, 2021, 21:52:40 »

Good thought and that should work just fine.

Charles 230SL · « **Reply #50 on:** February 27, 2021, 22:48:27 »

Is it common for these nuts to vibrate loose? I've had to retighten my dash wood twice in the past 3 years and I've even thought about using a dab of loc-tite. Fortunately the nut that works loose is in the center of the dash so I'm able to access it through the dash speaker opening - but it's still quite an aggravation to have to remove the grill and speaker. https://www.sl113.org/forums/index.php?topic=25760.msg184507#msg184507

wwheeler · « **Reply #51 on:** February 28, 2021, 01:12:30 »

I wouldn't think it should work loose. Maybe your idle is a bit rough and you should do the linkage tour.

I think that is why there is a self locking feature at the end of the new nuts. You can use the method I or Pawell suggested to create that. It is certainly possible that after a few ons and offs, the locking feature on the nut has worn off.

wwheeler · « **Reply #52 on:** February 28, 2021, 01:15:07 »

Quote from: wwheeler on February 27, 2021, 00:15:40

FREE PARTS: I have (30) spare blue plastic nuts and obviously don't need that many. Like Pawell's, they are not as smooth as a molded part but function just fine and have the blue color. These were printed using the STL file from mrfatboy. They need to be tapped and can be done so very easily with a 5mm tap. Also there is a plug in the hollow end that was used to support the nut during printing and it chips away easily.

I will ship these in lots of (5) to whomever is interested for FREE if you pay shipping (US only). Attached are pics. I will have to get a quote, But I imagine shipping would be no more than $5.

PM me if you are interested.

Only 15 left.........And shipping is $5.00

Vander · « **Reply #53 on:** February 28, 2021, 02:56:02 »

Wwheeler pm sent

wwheeler · « **Reply #54 on:** February 28, 2021, 03:11:27 »

5 left......

Charles 230SL · « **Reply #55 on:** February 28, 2021, 03:47:50 »

I won't run the tap all the way through so they'll be self locking - I'll leave about 1mm untapped. thanks Wallace

afeustel · « **Reply #56 on:** March 01, 2021, 04:10:01 »

PM Sent

wwheeler · « **Reply #57 on:** March 01, 2021, 04:50:32 »

Ok. All of the nuts are gone! It was a fun project!

Charles 230SL · « **Reply #58 on:** March 06, 2021, 02:39:44 »

hi Wallace, the plastic nuts arrived today - thanks! I plan to tap a couple over the weekend with a 5mm tap. thanks again for sending them.

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Author Topic: Blue Plastic Nuts For Wood Self Fabricated (Read 6788 times)