For the machinists-

For the machinists-

Postby areibel » Wed Aug 29, 2018 9:31 am

A question! (Bernd, Brian, MacG- you guys listening?)
I'm trying to build a dummy power truck and I am wondering if Derlrin would work for a block to mount axles into? I need to cut it to shape, mill out axle slots and then drill and tap for a base plate, pick ups, etc.. Is Delrin a good choice or would something else be better for machining ? Brass would work too, and I want something that will wear well but for a novice machinist I'm looking for something easy, and for a little over $4 a foot for the plastic I can mess up a few!
Thanks!
Al
areibel
 
Posts: 1746
Images: 7
Joined: Fri Jun 12, 2009 10:12 am
Location: Cambridge Springs PA

Re: For the machinists-

Postby Bernd » Wed Aug 29, 2018 12:41 pm

areibel wrote:A question! (Bernd, Brian, MacG- you guys listening?)
I'm trying to build a dummy power truck and I am wondering if Derlrin would work for a block to mount axles into? I need to cut it to shape, mill out axle slots and then drill and tap for a base plate, pick ups, etc.. Is Delrin a good choice or would something else be better for machining ? Brass would work too, and I want something that will wear well but for a novice machinist I'm looking for something easy, and for a little over $4 a foot for the plastic I can mess up a few!
Thanks!
Al


Loud and clear.

Yes it would work as long as you don't need to glue anything to the Delrin. It has good wear properties. If you do need to attach something to it consider tiny (00-90) screws. Opps I see you already mentioned drilling and tapping. Good luck and we want pictures. Even of the goof ups. :thumbup:
Image
User avatar
Bernd
 
Posts: 977
Images: 27
Joined: Wed Sep 02, 2015 8:43 am
Location: Rochester, New York

Re: For the machinists-

Postby areibel » Wed Aug 29, 2018 1:31 pm

Great!
I need to order a ball end mill (or 6, or 10- breaking end mills on TT Lionel shells is another hobby of mine), I'm hoping that would give a good enough finish but what clearance would you recommend? If it's a 2mm axle (.0787) and I'm looking at this chart-
http://www.harveytool.com/prod/Ball-Min ... gJljfD_BwE
They list a 5/64ths (.078), a .080 and a .085. It's a three axle truck so I don't want it too rigid (I'm assuming a little slop in the bore would help the operating radius?), but I'm not sure how loose or tight to go.
areibel
 
Posts: 1746
Images: 7
Joined: Fri Jun 12, 2009 10:12 am
Location: Cambridge Springs PA

Re: For the machinists-

Postby MacG » Wed Aug 29, 2018 3:10 pm

I have chosen Polyamide (Nylon 6 or polycaprolactam). The 2mm Tillig-axle has a diameter of 1,95mm. I have milled with a 1mm ball end mill the pocket with 2,05mm. A 2mm mill is too wide for 2,05mm. 1,8mm should be the maximum.
Lok-n-Roll.de - we send worldwide :wink:
User avatar
MacG
 
Posts: 948
Images: 11
Joined: Mon Aug 15, 2011 1:19 pm
Location: Dresden, Germany

Re: For the machinists-

Postby areibel » Wed Aug 29, 2018 5:35 pm

Thanks! I haven't used my mill for much more than a drill press, some experiments with other cutting jobs haven't gone too well (see above!) so I can use all the advice I can get.
areibel
 
Posts: 1746
Images: 7
Joined: Fri Jun 12, 2009 10:12 am
Location: Cambridge Springs PA

Re: For the machinists-

Postby Bernd » Thu Aug 30, 2018 4:42 pm

areibel wrote:They list a 5/64ths (.078), a .080 and a .085. It's a three axle truck so I don't want it too rigid (I'm assuming a little slop in the bore would help the operating radius?), but I'm not sure how loose or tight to go.


I'd go with .085". That gives you .007" clearance or .0035" per side. Quite a tight tolerance for TT.

Bernd
Image
User avatar
Bernd
 
Posts: 977
Images: 27
Joined: Wed Sep 02, 2015 8:43 am
Location: Rochester, New York


Return to General Discussion

Who is online

Users browsing this forum: No registered users and 0 guests