Custom 3d Printed Car Parts

by madmorrie

77K11015

Intro: Custom 3d Printed Car Parts

The ability of 3d printing to form any shape is quite remarkable. To be able to imagine a part, design it and then simply place an order online and have it arrive in the mailbox is amazing. Especially when the part in question could not realistically be made any other way.

Take for example these lock levers from my 1962 Valiant. The originals are a diecast aluminium and feature a very fine spline. I doubt they would be able to be manufactured any other way. Even with CNC machining I imagine the part would have to be made in two pieces if it was possible at all.

The replacements were needed due to an oversight on my part. I had made some lovely new door trims for my the Valiant. The fronts turned out so well i went ahead and made the rears to match. However in my enthusiasm I did not take into account the lock levers which only feature on the rears. Show here is the locking lever spline protruding through the trim baseboard before trim, and after I had finished the trim with the padding. No spline protrudes and therefore the original lock levers do not fit. So how to fix this without remaking the whole door trims?

3D printing to the rescue!

STEP 1: Measure

Carefully measuring the spline dimensions gave me the basics. A 20 spline shaft with an outer diameter of 8.29mm and an inner diameter of 8.08mm, a length of 12mm and a spline depth of only .2mm. This would surely be stretching the the limits of 3d printing accuracy, but I had been very happy with shapeways SLS fine detail on some previous models, so I thought it would be worth a shot.

STEP 2: Modelling the Critical Details

To the modelling. I am using modo because it is what I am competent in - a dedicated CAD program would be much better no doubt, but the principles should apply to all 3D packages.

Starting with the critical details first, in this case the splined section, I made a cylinder of the inner spline dimension. A key point here is that the cylinder had 80 sides. This allowed my to select every 4th side and scale from the centre point to the outside spline dimension. This forms the basic spline shape.

STEP 3: Finish Modelling

From there I fine-tuned the inner and outer ends of the spline as needed, and then made the rest of the lever model around it. Taking into account the fact it needed to me about 10mm longer to clear the new door trim. I also made the base quite wide to cover the hole through the trim and was able to form the countersunk screw hole on one end of the splined section. The basic shape of the lever was supposed to be based off the main door latch handle so the style kinds of matches.

STEP 4: Upload and Order the Design

After a few hours of tweaking the design I uploaded the model to Shapeways. I had to save it out a few times to make sure it uploaded in the correct dimensions, but once I was sure it was correct I ordered 2 in black strong and flexible and waited for the postman.

STEP 5: Install Parts

A few weeks later my nicely bubble wrapped levers arrived and I went straight out to test them. To my slight amazement and immense relief, the splines came out perfectly, and they slid straight onto the shafts in the doors. My diligence in measuring everything paid off and I now have some custom door lock levers, and didn't have to modify my nice new door trims. Initially I was intending to order them in stainless steel, however the plastic ones seem to be perfectly strong enough, so unless they break I will stick with them.

Now, what to build next...

16 Comments

3dcarmods 8 years ago

Our website is all about that. We plan to 3D scan OEM parts that can be modified and 3D printed. Some parts can be plastic but others must be stronger. Thanksfully, you can use 3D printing to create yourself a MOLD. With that mold, you can do carbon fiber parts or do metal parts with a cold casting method :

If a part doesnt exist, we can design/3D print it for you. New features are coming every week.

www.3Dcarmods.com

MichaelW146 8 years ago

Finding auto parts is frustrating when you don't want to pay the full price, sometimes I wish I could just create the parts myself. It sounds like you actually used a 3D printer to make your own car parts. How did that would out for you, did it work and how did you know the machine would make the exact measurements? <a href='http://www.alliedauto.ca' > http://www.alliedauto.ca</a>

MichaelW146 8 years ago

Finding auto parts is frustrating when you don't want to pay the full price, sometimes I wish I could just create the parts myself. It sounds like you actually used a 3D printer to make your own car parts. How did that would out for you, did it work and how did you know the machine would make the exact measurements? <a href='http://www.alliedauto.ca' > http://www.alliedauto.ca</a>

Melia Esperas 9 years ago

looks good, how do you translate measurements in 3D? not all programs use the same scale. im worried that what in .5" in Softimage 3d space is not .5" in 3d printer program space. Do they work with you to fix those issues? i was thinking of uploading a perfect 1x1x1 square along with my model to use as a scale reference if needed.

madmorrie 10 years ago

Thanks all for the comments. Yes, the original was chrome plated, and had the screw exposed. On my version the screw head is much more recessed so is less visible anyway.
I had intended to get metal ones printed and then polish them, but I will see how the plastic ones hold up to general usage first. They seem pretty strong to me.

And yes, while this is a relatively simple part, it does show the opportunites for this kind of thing. This was still way cheaper, faster and easier than most options than cnc or manual machining.

XenonJohn 10 years ago

Hi there fellow Valiant owner.

About to print some HT lead spacers for my 1968 VE Valiant using my Makerbot. I probably have the only one in the UK (Valiant that is).

John

loop 10 years ago

Nice job - voted because of the car. Love the old R and S-type Vals.

justajo 10 years ago

It does seem like the screwhead should be covered, but maybe on the original it wasn't. Do think the original would have been chrome-plated. Could have that done. Still looks good tho. (That styling, shared by the entire Chrysler line, came out when I was a teen and was a refreshing design departure from the other makers. Wasn't that well received by the unimaginative public. I wanted one anyway and still do.)

dodgedartgt 10 years ago

Just as an aside, we plan on picking up a '62 Valiant Signent 200 2dr as our 14yr old daughter's first car over our summer holiday. She is a tremendous kid and student, really liking old stuff. When I showed her a beautifully restored one locally, she went gaga and doesn't want my '67 Cuda fastback anymore.

onemoroni1 10 years ago

Nice adaptation of 3D printing to solve a problem.

maxo90 10 years ago

Why without cover cap on it ?;]

monkeyracing 10 years ago

This is a cool project. I love what can be done with 3D printing and the service that Shapeways offers.

This could also have been accomplished by a machine shop using a broaching tool. The tradeoff would be expense, but the result would be a very strong part.

Aloxite 10 years ago

Great project. I have a 67 Valiant myself. If you do need parts call Wildcat Auto Wrecking. They have several of the early Valiants and Lancers. I'm happy to see more old Val's being cared for.