Soldering brass [Archive]

ken_nj

Jun 23, 2009, 09:07 PM

Did a search here and in Scale Boats and didn't come up with a worthwhile hit so I'll start a thread. I am going to be fabricating a railing for my current boat project. I am using 3/32 K&S brass tubing as the railing around the perimeter of the model, total length is about 10 feet. An upright will be spaced every 2 inches. There are about 60 uprights. Each upright is filed to conform to the horizontal rail and each one is a 7/16". I am decent at soldering. I have a 30 watt 40-45 watt iron and a torch connected to propane. My current plan is to first clean connections with 600 sand paper, flux, then solder. I'll have a jig to hold everything in place. and maybe tin the uprights before I solder it to the rail. Does this sound good? Do you have any other suggestions? If you need a pic, I can post one.

Of course after Deadliest catch.... :D

Olscuzbut

Jun 23, 2009, 09:46 PM

Sounds good Ken. Might use small diameter solder to prevent blobing and running. Also flux remover or alcohol after completing your solder work for cleanup.

ken_nj

Jun 23, 2009, 10:04 PM

The solder I have is .032 diameter 60/40 rosin core. Don't have flux remover but I certainly think I can find some alcohol. :D

I very concerned about getting excellent solder joints.

green-boat

Jun 23, 2009, 10:12 PM

Want good joints....... practice, practice, practice,practice, practice, practice, practice, practice, practice, practice, practice, practice, practice.....

Since everything is going to be in a jig, I wouldn't worry about tinning the uprights.

If you mess them up then hit the joint with a wire wheel mounted in a Dremel. It is also great for removing flux.

norgale

Jun 23, 2009, 10:19 PM

You'll get good solder joints alright but be prepared for a lot of filing and cleaning up the joints.Get the smallest diameter solder you can. I got .015 wire at Radio Shack for $5, thats 1 oz. It's very thin but much easier to handle than the thicker wire. I learned to hold the iron tip away from the actual joint a bit and let the heat travel up to the joint. Once the flux started to sizzle I hit it with the wire and that worked very well for me. Got good solid joints with a minimum of clean up. Big problem is keeping the parts from moving around. Make you jig well so that doesn't happen to you. Otherwise I'll be hearing you holler way down here in Fla. Pete

Umi_Ryuzuki

Jun 23, 2009, 10:19 PM

Here's a quickie how to...
http://www.rcgroups.com/forums/showpost.php?p=6169253&postcount=63

I know Ropanach will create a jig, by carving grooves in a board.
I sometimes use pins and a board...

:)

GreenAmphibian

Jun 23, 2009, 10:20 PM

Sounds like it is all great advice.

jaguar75

Jun 23, 2009, 10:35 PM

While solder is still "wet" wipe it with a dry shop towel,providing the brass is tightly jigged up.I do this while using a torch with flux handy to clean the joint during and after solder melts.I have soldered brass and copper for 30 years doing this.

ken_nj

Jun 23, 2009, 10:38 PM

Yup that's close to what I am doing, except one rail and the stanchions are about 7/16'. Hopefully I will not have any clean up except the flux.

jaguar75, I planned on using an iron so I don't think it will stay wet enough to wipe it, right? Unless I hit it with the torch for a sec after applying the solder with the iron.

Greysquirrel

Jun 24, 2009, 09:45 AM

Having the joint clean is important, after you sand, wash with soap and water, dry making sure you don't touch with your bare hands and transfer body oil to the joint and then wipe with a clean cloth and alcohol.
And if you think the solder will run where you don't want it draw a line with a soft pencil to where you would like the solder to stop and it will not flow past that point.

jaguar75

Jun 24, 2009, 10:34 AM

I would still use flux.Actually the regular paste flux to clean up the soldered joint and use Oatey brand #95 Tinning Flux(Home Depot) for the initial joining together of parts before soldering.Use a small paint brush.The #95 solder has solder powder mixed into the flux paste and makes a cleaner and stronger joint.

mfr02

Jun 24, 2009, 10:41 AM

Telstaruk

Jun 24, 2009, 12:34 PM

Hi
For soldering small parts (like handrails) I use a solder paste. It's a mild flux with solder powder mixed in, used in industry for surface mount electronics, simply clean the areas to solder, apply the paste sparingly with a small brush, assemble, wipe off any excess,and apply heat. with the solder being in the joint you get no blobs

Shaun Hendricks

Jun 24, 2009, 12:46 PM

I've often wondered if there wasn't a cleaner way to do railings and such. Soldering does require a lot of practice and jigs, etc. etc.

Has anyone tried drilling and pinning the railings?

What I'm referring to is that most of that K&S brass can be had hollow. If you put in a fill pin the length of the stanchion after concaving the top to mate to the rail, you could put a small drop of solder on the top of the stanchion. If your rail was drilled to fit the pin, cleaned and slightly filled with flux, you'd only have to heat the rail with a micro torch and set it atop the pinned stanchion. The solder would melt, flow into the hollow rail creating a rivet head strong bond to the stanchion and there should be almost no clean up. You could even use cooling clips (heat sinks) to preven the heat from one rail stanchion place travelling back to a previously done stanchion point.

If you ran the pin longer than the stanchion, you'd only have to drill a small matching hole in the deck, some glue and presto, firmly held stanchion and railing.

Anyone try this? Obviously, there's a bottom end to the ability to do this as the hollow tubing only goes so small, but it's just a thought.

ken_nj

Jun 24, 2009, 03:29 PM

Shaun, I was thinking of pinning the joints and doing what you described. The only problem was the exact precision required. I already have the holes drilled in the bulwark using a jig so they are evenly spaced. Now I would need to get the exact location in the rail. I don't think I would be that exact drilling the hole in the rail to get the precision required. So I am going without doing it without the pins into the rail. I will be pinning the stanchion at the bottom with CA to glue the rail to the bulwark.

So I can use Oatey brand #95 Tinning Flux to both clean and solder the joints?

Shaun Hendricks

Jun 24, 2009, 05:26 PM

Well, I was thinking in reverse, I probably wouldn't drill the decks/bulworks first but build the rails then work on where they exactly go on the model. Perhaps that's too backwards thinking for proper modelling.

Greysquirrel

Jun 24, 2009, 05:34 PM

Question: Are you guys using Silver Solder or Acid Core for soldering your brass?

Umi_Ryuzuki

Jun 24, 2009, 07:30 PM

I try to use no core 60/40, with a past flux.
I silver solder primary or major joints, and then use
the lower temperature 60/40 for other points on the
mast or rails.

:)

ken_nj

Jun 24, 2009, 08:24 PM

I planned using 60/40 rosin core, that's what I have on hand. Or should I use Oatey brand #95 Tinning Flux like was suggested before?

Shaun, the reason I drilled the boat first was that that would give me the exact spacing I wanted, and using a pin in the hole on the boat, that would hold the stanchion in position while it is soldered to the rail. Since the hull has a sweep to it towards the bow, the posts (stanchions) will be vertical to the waterline, not to the sweep of the boat. I would essentially be using the boat as part of my jig.

I understand it may make sense to build the rails, then attach to the boat, but I think with how many stanchions I need to solder (~60), they will look perfect when I am done this way.

Shaun Hendricks

Jun 24, 2009, 11:20 PM

Yeah, that's what I thought. I was building them backwards... ah well, it was an idea.

Umi_Ryuzuki

Jun 25, 2009, 01:02 AM

Yeah, that's what I thought. I was building them backwards... ah well, it was an idea.

Building a jig first would ensure correct alignment of all your pieces, and
save you the balancing act that I do in building them upright.
All the cross bars between stanchions don't always solder level.

To assist with that I sometimes cut a block of wood to set the
cross bar heights below the top rail. The block helps to keep the
lines parallel.

Coversely, building the jig, and then rail creates the consistent lines, and
then the stanchions could be set in slighty oversize holes and cemented in place.

There's no wrong way to do it.

:)

norgale

Jun 25, 2009, 08:15 AM

The only thing wrong with building them in place is overheating the metal and scorching the wood or paint on the boat. I did mine both ways and find I like building with the jig whenever I can. Keeping the stanchions straight up on the sheerline can be a challange and in that case the soldering is better done on the model. In that case just heat the metal till the flux starts to sizle and then just touch the joint with thin solder and your done. Takes practice as somebody else has already mentioned here. pete

green-boat

Jun 25, 2009, 08:29 PM

The only thing wrong with building them in place is overheating the metal and scorching the wood or paint on the boat.
Try resistance soldering, localized heat.

ken_nj

Jun 25, 2009, 08:59 PM

What I did was use some aluminum sheet, drilled holes in it for the locator pins which stick up through the gunwale. You can see this in the pic. On the workbench, I cleaned, fluxed and added a drop of solder on the curved end of the post which connects to the rail. I placed the post over the locator pin, positioned it, and placed the rail on top of the post. Next, applied the soldering iron to the top of the rail and some downward pressure. The iron heated the rail, solder and post enough for the solder to melt. I could see & feel the rail drop down onto the curved post. So far no need for solder cleanup on the joint, just need to clean any flux. Although I have to cleanup solder from the iron tip on top of the rail. The aluminum sheet draws away heat coming through the post to prevent the fiberglass gunwale from possibly melting from the heat. Maybe I don't need this aluminum.

I tried a tiny piece of curved brass sheet on top of the rail, placing the iron on that, then indirectly trying to heat the joint, but it did not work so far. If this did then I would not have to do any cleanup on the rail from the iron tip.

Long winded, but you should get the point.

E-Challenged

Jun 25, 2009, 11:51 PM

I would try taping straight top rail pieces to a piece of corrugated cardboard with stips of duct tape and use some kind of "upside down U shaped wooden jig" with a vertical hole in it slightly larger than the stanchion tube to keep each stanchion vertical and at right angles to the rail and solidlly in place while soldering. After soldering all stanchions, carefully form top rail to shape of hull and mark locations for drilling stanchion mounting holes. Maybe make some kind of a jig to keep stanchion holes centered and spaced evenly while drilling to match stanchions.

ken_nj

Jun 26, 2009, 12:05 AM

E-Challenged, so far using the gunwale as the jig has been working great. The pre-drilled holes in the gunwale give me the spacing and positioning for each stanchion. The rail was preformed to the sheerline of the gunwale, so all that needs to be done is solder them together. I have about 12 stanchions in place and they look perfect!

785boats

Jun 26, 2009, 12:44 PM

ken nj.

To save having to clean up any solder on top of the rail, try wiping the tip clean on a piece of damp cloth or sponge first. Or better yet you could buy another cheap 30w iron & use that one for heating the rail without any solder on it.

Just a thought.
Paul.

ken_nj

Jun 26, 2009, 04:11 PM

785, will give wiping the tip clean a try. May wait until one side is done then do cleanup.

Some of the stanchions look crooked in the pictures, but not so bad in person, maybe the flash or lighting. Crooked ones are easy to straighten out. Coming out pretty good so far, making progress.

Definitely looks better in person now that I see the pictures in the thread.

ken_nj

Jun 26, 2009, 06:41 PM

I did straighten out a few stanchions. It was easier to use a small 1/4 inch wide file to clean up the solder on top of the rail. Once I'm done soldering I'll go back and clean up some of the solder joints.

norgale

Jun 26, 2009, 07:35 PM

That looks great Ken. I was going to show you some of my railings but now I won't. Your's look way better than mine. :D I wanted to leave mine brass color and coat them with clear but I made such a mess with the solder I had to paint them. They don't look so bad if you don't get too close. Ha! Pete

ken_nj

Jun 27, 2009, 01:16 AM

Thanks for the compliment! Going to hate to paint them, but the real boat does not have brass railings, so they will be painted as well.

ken_nj

Jun 28, 2009, 01:32 PM

So I have the port side done. Did a little filing and cleanup. Brass is nice and shiny now. One stanchion came loose. All of them seem pretty solid. I grabbed each and gave a little tug on them to make sure they were secure. I was looking through a magnifying glass to check where to file. Gave a sanding with 400 grit. Amazing that I can hardly see any solder, yet they are so secure.
Onward!!!