what way is best to stretch sprue?

[Dave Stone]

This is probably a question that has been asked hundreds of times. How and in what way is best to stretch sprue? So far I have been using very thin cotton and a light dope (used to make balsa planes) but would like to learn how to use sprue as it seems to be the most used method.

[Timmy C]

There is no one "best way" to do it. You'll get different experiences and methods from the members here. Some ways work better for some, some for others.

I do it the same way as Jim Baumann's method in his how-to:

Light end of sprue runner until it just catches flame, blow out and dab one end onto piece of paper/card on workbench and slowly but firmly pull until the desired line thickness is achieved.The trick is to pull initially real fast to get it thin, then as the plastic cools, slow down the speed of pulling

If you are going to need LOTS, set up two paint tinlets on bench, and follow the procedure above but when you run out of space simply bend it around the paint tinlet and continue on till plastic cools and your thread breaks. You will need to practice a little to get consistently thin sprue. Black sprue is THE cheapest modelling material we will ever use pro rata, so if you are not satisfied with result simply discard it and start again.

To rig, use a small pool of liquid cement on bench, dab the end of chosen rigging piece in cement and with tweezers attach to ship/yard let set for 5-10 seconds and draw the other end to your chosen attachment point. Dab on a minute amount of liquid cement and draw the sprue piece thru the cement and let set. With liquid cement on the end of a toothpick, melt the plastic of the spruee and voila you have a neat attachment with no furry ends or scissors etc

Having rigged some shrouds for example you may wish to tighten them. Hold model over a consistent smoke source such as inscence or cigarette (I gave up, hence joss sticks) and the hot smoke will tighteen the rigging like magic.My advice is take a very old/scrap model and practice as it is very easy to completely rig a model and then at the tightening stage get too close to heat source and completely UNRIG the model.... with resultant fury, frustration and vulgar language...!!

[Dave Stone]

Thank you. I will try that out asap

[Ron Smith]

With a custom built, dual overhead cam sprue stretcher of course.............

[Dave Stone]

Ahhh there is always a comedian