Honda CB750 Sandcast

How to?? Reproduce warning light tubes of the gauges

CB750faces.com (Lecram)

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The tube in your gauges that guides the light beam to the lenses is often dried and need to be replaced.

There is  kind of 'chicane' in the tube and you cannot use a straight tube for it.

I have produced my own ones, by making a mold and using heat shrink. I made the mold of epoxy resin. I closed one side of the original tube with tape and poured some epoxy resin in it. After a couple of hours, the resin had been cured and I was able to get the mold out of the tube.

I have used a heat shrink tube of 1", put the mold in it after heating it up, the heat shrink got the shap of the mold. I only had to cut of the rest of the heat shrink and ready!

See pictures:

The original tube and the mold:



The mold in the heat shrink




The heat shrink after heating


The result next to the original tube. It is not exactly the same, but the dimensions are correct. The tube is not visible after closing the gauges.







Riccardo

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Great work Marcel.

Have you tried with black silant around the mold?

It is more soft under the faces.

Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New


CB750faces.com (Lecram)

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Great work Marcel.

Have you tried with black silant around the mold?

It is more soft under the faces.



Thanks, Riccardo.

What do you mean with 'black silant' ?




Bickle

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A nice solution....do you have any concerns that the heat shrink might continue to shrink from the heat of the bulb?

Steve


CB750faces.com (Lecram)

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A nice solution....do you have any concerns that the heat shrink might continue to shrink from the heat of the bulb?

Steve

That is a good point. I will test this soon. The heat shrink will shrink at 125 degrees C, I don't know what the temp is of the bulb at that point




ashimotok0

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How about using silicone tubing. That would conform and take the heat. I think normal heatshrink may continue to shrink too. There must be quite a bit of heat as is borne out by the fact that the orange jewel deteriorates so badly. The white rubber is definitely inferior to the earlier black and goes hard and disintegrates (definitely a backward step by Nippondenso!).

http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=2885128


Cheers  AshD


CB750faces.com (Lecram)

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I have just started the long term test. Let's see how it ends this evening.






Riccardo

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Great work Marcel.

Have you tried with black silant around the mold?

It is more soft under the faces.



Thanks, Riccardo.

What do you mean with 'black silant' ?



Black silicon/sealant, used in boat repairs.

Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New


tomcourtney

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It seems that the Green jewel for the neutral light seem to melt the most in gauges i have had apart, And most probably from having a larger wattage than 3 watt bulb the flasher flashes 50% so would have less heat but seem prone to fadeing and from the sun too, and the oil and hi beam seem to survive ok, TC
I sold my first Sandcast and regretted it till I bought it back 6958/7149, its taken a few years to get a couple more 6946/7169, and 6970/E6956



Riccardo

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Marcel,

we wait your test.

Please, post the pics with working test.
Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New


CB750faces.com (Lecram)

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I have bought some LED bulbs and they work fine with the tubes. It is quite similar with the glow bulbs, but a good alternative. Not original though.




Riccardo

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Marcel,

post photos if possible.

We are avid to see the effect.

Ciao
Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New