Garden Railway Forum

Hi Steve
Just out of interest, are the wheels filament printed? How much of the chassis/mechanism is printed?

Rik

ge_rik wrote: ↑Thu Mar 24, 2022 8:38 am Hi Steve
Just out of interest, are the wheels filament printed? How much of the chassis/mechanism is printed?

Rik

Hi Rik

A brief brief run do, most things are 3D printed including the wheels and cranks.

Things not 3D printed are as follows as best I can remember:
Motor
Nylon gears
Silver steel axles
Brass axle bushes
Brass washers
Steel bolts for cranks, crossheads etc.
Piston rods 2mm piano wire
Brass sleeves inside pistons for above

I think that about covers it, everything else either from FDM printer or resin printer, depending on detail required.

Do you have to turn the wheels on a lathe after printing or are they usable straight off the printer?

Rik

ge_rik wrote: ↑Fri Mar 25, 2022 8:05 am Do you have to turn the wheels on a lathe after printing or are they usable straight off the printer?

Rik

Thats what I was wondering as well. I find that the wheels print circular enough, both resin and filament, but getting the axle bore to print accurately is next to impossible and trying to drill/ream/file by hand is highly unsatisfactory.

philipy wrote: ↑Fri Mar 25, 2022 9:40 am

ge_rik wrote: ↑Fri Mar 25, 2022 8:05 am Do you have to turn the wheels on a lathe after printing or are they usable straight off the printer?

Rik

Thats what I was wondering as well. I find that the wheels print circular enough, both resin and filament, but getting the axle bore to print accurately is next to impossible and trying to drill/ream/file by hand is highly unsatisfactory.

I use a 3mm axle and use a 3.1mm hole through the wheel in CAD. As things always change size on printers, I have found this to be ideal and a 3mm hand drill bit just takes off a tiny amount, not enough to make it run un-true and 9 times out of 10 leaves me with a perfect running wheel. I have found that even some manufactures of wheels, you still get one with a wobble now and again, so I am happy enough with a minor wobble if it happens, if it's too bad I just print another wheel.

Thanks Steve, thats virtually exactly what I do (try to do) even as far as using the 3.1mm bore to allow for distortion, but try as I may I cannot get them to run true with using the 3mm handdrill. I had a clear up this morning and threw out 15 unsatisfactory wheels from my last two projects and I know I've already chucked some more along the way.