Drawbars parts RT-3

[CrazyKeys72]

Hi guys, I have a question for you ..... can you not find these areas of the drawbars bar? When I disassembled it for review, I found several broken ones I glued with attack. But I would really like to replace them. Thanks for your help.

[Drummer55]

You may be better off finding a replacement drawbar setup. Don't think those parts are going to be easy to come by.

[Tim_at_Jonas]

Find someone who can scan one and 3D print new ones.

[CrazyKeys72]

In fact .... I had thought about this, I did a lot of research, with no results, before asking you, and I think it's the only solution.
Thank you !

[muckelroy]

This can happen when using cleaning solvents to clean the drawbars. Some solvents react badly with the plastics used to hold the drawbar bus bars in place, and crack them.

Find donor parts, or make your own with a 3D printer. Both are suitable solutions, as long as the material you make them out of is an insulator (not a conductor), and as long as it does not have a bad chemical reaction with the metal of the drawbar bus bars.

[ChristopherDB113]

Fortunately I haven't had to buy any replacement parts, but I've always been under the impression that they were available, though not cheap. I'd think it would be the same part used in a B-3, C-3, and others.

[CrazyKeys72]

They are all the same for the smooth drawbars series .... unfortunately I found them in these conditions, those cracked after bonding are working .... but I would like to prepare myself for a future job.

[Bobmann]

I have never seen these clear plastic parts that are NOT full of cracks. I theorize that this type of plastic simply degrades over time regardless of whether they were cleaned or not. The cracks seldom result in the parts actually coming apart, at least in my experience.
I doubt that you will find any of these clear parts as I am going to assume that they are all cracked, so whatever you find will be no different than what you have now.
Since smooth DB are so rare, and those that are posted for sale are so expensive, it is doubtful that anyone will actually take them apart to sell the pieces.
There is at least one other version of this part that is made from a black plastic that looks to be more solid and durable.

I really see no reason to replace these, as they will function perfectly well regardless of the cracks, and even if they have come completely apart, you can to glue them back together...just my opinion.

I do not know enough about 3D printing to comment as to how difficult it would be to create the program to reproduce these, or how the plastic used in the process will hold up over time.

Bob

[CrazyKeys72]

Dear Bobmann .... how are you? I hope everything is ok .... it's a lot that I do not feel you .... I'm very happy to find you again.
You are absolutely right when you say that the details in question do their work even if they are cracked, and in fact have already been 3 years since the first review, and are working .... it's just my fixation, however with today's systems and the 3D printing with the materials available I think there should be no problems, it needs to have rigidity and flexibility at the same time. We will see later ....
However, given that I have the opportunity to talk to you, allow me to present my thoughts on these details.

What I would like to fix in this problem is the perpendicular linearity of the bars when the rudders flow over it ... as I saw in your movies I have passed the fine-grained emery cloth, however I have a drawbar sector in which the first two from the left they sometimes do not work and they do not give sound until you move them finding a contact, this happens when they're both out ... that's why when I'll have time I'll take the whole bar down again ....

Moreover, since we are talking about it ... I have my own idea, and it concerns those small plastic sectors that are under the plates that fix the contact bars ... these sectors have undergone deformation in the years under the tightness of the two screws, and once dismantled, it is difficult to re-assemble them at the same place where they were before, and therefore a new deformation on the bars is produced even if only slightly.
What I think is that we should replace today, after a long time .... the bars and these sectors and thus have the whole flatness of the bars.

[Bobmann]

There are a couple things to check:
Sometimes that contact spring can get deformed to the point that only one of the 2 contact points actually touch the bars.
Remove that offending contact and make sure that it is not bowed at all, it should be straight and flat when not screwed in position.

Another thing that will cause issues is that small resistance wire that is on the bottom of the contact that connects the 2 contact points. Many times that is broken or missing.

That soft plastic part under the metal hold down is simply an insulator so that the metal hold down does not short out the bars. I suppose that under certain conditions the bars could not be held captive securely enough and one could end up slightly higher than those on either side, but I believe that would be rare. It is easy enough to check, however, when the assembly is out just by placing a straight edge over the row of bars and see if they all are laying flat.

Hopefully this all makes sense. Please let me know if some pictures could help.

Bob

[CrazyKeys72]

Yes .... I add a picture of what I did. I have applied computer connectors which have just 9 pin positions overhauling all the contacts ....
for when you disassemble the bar, speeding up the operation without having to make new welds, even those of the drawbars are in place.
I plan to rebuild those deformed sectors, because I think their deformations lead to change the flatness, when you are going to tighten those two screws.

But it's also right as you say check with a line.
Thanks Bob ... a grade greeting.