View Single Post
Old 8th Jun 2010, 11:19 am   #18
Billy T
Retired Dormant Member
 
Join Date: Feb 2008
Location: Auckland, New Zealand
Posts: 631
Default Re: Copying a control knob by moulding

I have an EKCO SW86 to undergo restoration and it has one knob missing. I can't see myself finding a replacement knob (or set, see below) so I am thinking of casting a replacement, but perhaps I am missing something here? After twice reading through all the very comprehensive advice, I see a number of alternative materials for making a mould, but I can't see any recommendation on the preferred material to actually cast the knob itself. There is mention of fillers for colouring but they are not detailed either, and as a novice in this area, trial and error does not appeal. The Resin Supplies link seems to be non-functional at present.

So, my question is, what is the most successful (recommended) casting medium to use, and what filler or colourant has been found to give the best match for dark brown bakelite? As you will see from the rear image below, this surviving knob has a bad crack across the middle as well. It will probably be ok if the surrounding channel is cleaned and filled with araldite, but for colour matching I'll probably have to make three.

Cheers

Billy
Attached Thumbnails
Click image for larger version

Name:	EKCO SW-86-4.jpg
Views:	445
Size:	56.5 KB
ID:	36771   Click image for larger version

Name:	EKCO SW-86-5.jpg
Views:	508
Size:	64.4 KB
ID:	36772  

Last edited by Billy T; 8th Jun 2010 at 11:27 am.
Billy T is offline