Member postings for Brian John

I have finished the second crankshaft using 243 degree soft solder. It does not stay nicely in place like the solder paste so there was a bit more to clean up afterwards but it is certainly a lot cheaper. I will stop at two crankshafts as I am only building two engines.

Once I solder the cylinders to the steam chests then I only have the piston assembly to complete. The instructions say to fit the piston slightly oversized to the piston rod and then with the piston rod supported between centres in the lathe, to turn the piston to fit the cylinder. That seems overly complicated and I doubt that the two M3 X 5mm grub crews will hold things firmly in place while the piston is machined. My preferred method would be to cut the piston diameter to fit while the bronze work piece is mounted in the chuck. The cylinder can easily be placed over the piston to check for fit. Once a good fit is obtained, then part off and drill/ream the centre hole.

Why machine the piston while it is fitted to the piston rod ? I do not see any advantage to that.

NOTE : I went to Rustys today but the guy with the second hand tools says he does not have any plumbers irons. I think I will use the solder paste for the steam chest/cylinder assembly.

Edited By Brian John on 13/08/2017 08:30:26

Edited By Brian John on 13/08/2017 08:32:34

What is large diameter copper pipe of that size usually used for ?

I have completed one crankshaft using the solder paste. It fits well and runs smoothly in the bearings. The large plastic syringe of solder paste seems to be mostly air and that makes it an expensive option. I will use 243 degree soft solder on the next crankshaft. The M2 X 2mm grub screws are removed after the solder has set.

Removing the middle part of main shaft turned out to be more trouble than I thought. I had intended to use the slitting saw on the lathe but the main shaft would have interfered with the lathe chuck. I then opted to use a cutting wheel on the Dremel tool but that only cuts half way before the tool comes up against the main shaft. I had to finish off with a hacksaw and hand files.

Edited By Brian John on 12/08/2017 05:51:21

I have had another look at the Bengs website and it seems they have used solder paste for both the crankshaft and cylinder/steam chest assembly ? That looks like a lot of solder paste on the cylinder and steam chest !

**LINK**

NOTE : I had another go at reaming the crank arms today and I had better luck this time. The two shafts are now parallel. I am holding the crankshaft in place with M2 grub screws until I decide what to use : solder paste, soft solder, silver solder or Loctite. I have enough spare crank arms so I may even make up four crankshafts and try each method to see which one works the best.

Thanks Ian. I knew I had to tin the iron but I was not sure of the procedure. I know I have seen them at Rustys markets ; there is always a guy there selling old tools. They are open tomorrow and I will have a look but when you want something, they never have it !

For a small job like this, I would think one iron would suffice.

Thanks. I have called around this morning and nobody has them on the shelf. Plumbers do not use them anymore. Blackwoods can get in a 16 ounce iron from Sydney but it costs $75. Now that I know what to look for I will check out ebay.

There are some on ebay : any suggestions as to what size I need ? I am looking at an EVRO #10 which has a 25mm square tipped head. It is copper tipped.

http://www.ebay.com.au/itm/Vintage-Copper-EVRO-SOLDERING-IRON-25mm-Square-TIP-Old-Antique-Hand-Tool-46-/201661801881?hash=item2ef3fae599:g:dZwAAOSw-kdXzTRb

NOTE : I just remembered that I have a small portable gas stove. I could also keep the iron hot in that rather than use my silver soldering burner.

Edited By Brian John on 09/08/2017 01:24:32

Edited By Brian John on 09/08/2017 01:47:16

Yes, I can see that now. I will call around tomorrow and ask who has such a thing. Do plumbers still use those sort of tools ? What size iron should I be after ? Is red hot sufficient ?

Edited By Brian John on 08/08/2017 12:44:44

Okay, I will try the torch to heat things up more tomorrow. I had intended to use the large torch with the medium burner once I had things tinned sufficiently.

Yes, I know it is not real silver solder. It is only for soldering these parts and perhaps the crankshafts. This is what they suggested I use on the crankshafts for the flame eater engine. I did try to bash the test parts for the solder paste apart with a hammer but they are really stuck together so I know it works !

I also have some 180 degree soft solder I could use. Which is more suitable for this application : 243 or 180 degree ?

Edited By Brian John on 08/08/2017 08:55:36

I found somewhere in Cairns that sells the silver solder paste : Whitworths Marine. You can see the syringe in the photo below. Also in photo 1 is the 243 degree soft solder, the plumbers flux paste and the soldering iron I had intended to use to tin the cylinder and the steam chest. I spent the afternoon making sure everything fits together correctly first. I also cut two stainless steel rods 2.3mm X 10mm long which will sit in the steam holes which must not be blocked. You can see them sitting in the holes in the cylinder supported from below with a piece of aluminium. This is probably not necessary but I am getting a bit paranoid about stuffing this up : a lot of work has gone into these two parts !

I tried tinning some scrap brass after first applying flux to both sides. I cannot get a nice film of solder like they do in the videos ; I just end up with a mess although the parts did stick together after heating them up with a small blow torch (items 1 and 2 from the right).

I then tried the solder paste and the blow torch which worked better (item 3 from the right). I also tested the solder paste on the stainless steel rod to make sure it would not stick to the brass and it does not. It looks like I may have to use the solder paste.

You almost need three hands for this !

Edited By Brian John on 08/08/2017 08:34:18

Edited By Brian John on 08/08/2017 08:35:34

Edited By Brian John on 08/08/2017 08:36:38

Edited By Brian John on 08/08/2017 08:37:59

My mistake : the instructions say to soft solder the crank but all the warnings against silver soldering were in the flame eater instructions.....I am not sure why. The two crankshaft assemblies are the same although the Danni crankshaft is a bit smaller.

Hopper : my initial attempts were done with a reamer. I had two goes at it with the two crankshafts and both were crook. I will be reaming them again after I Loctite the crank arms together.

Roy : The solder paste would have been easier to use than the soft solder. I know I bought the stuff on ebay from the US...I just can't find it after the house move !

The instructions are very strict about not silver soldering the cranks due to the risk of distortion. What do you think ? It would certainly make things easier for me if I could silver solder it.

...but first of all I have to drill those holes in the crank arms and get things lined up properley.

Edited By Brian John on 06/08/2017 11:57:45

Hopper : I think I did drill and tap after drilling the main holes (it was a while ago) but still ended up with things all askew. I was surprised because I had done exactly the same thing with the flame eater engine and I had no problems. Maybe that was beginners luck !

Yes, I will definitely use Loctite next time.

The cylinders are now milled and drilled and ready for soldering to the steam chests. I still cannot find that silver solder paste I ordered from the US. That would have been ideal for the job. I might move onto the crankshafts now and see how I go with my soft soldering skills before coming back to the cylinder/steam chest assembly.

The crankshafts are one of my few unfinished parts. I had trouble with these : I carefully drilled the holes in the crank arms but the shafts are not parallel. I had intended to do the same as you with the grub screws and I had already drilled and tapped the crank arms for that. I may yet try the solder method. I bought some more crank arms and these I will Loctite together before drilling them in the vice at the same time. Hopefully that will keep the shafts in alignment.

NOTE : I did not have this problem with the crankshaft of the flame eater engine.

Edited By Brian John on 06/08/2017 01:25:00

That is very nice work ; I really like the idea of a twin cylinder engine. How did you make your crankshafts ?

I have been thinking about the soldering of the steam chest to the cylinder while I complete the milling of the cylinders. The solder must fill the two inner holes on the side of the steam chest (the two outer holes will be plugged with timber or stainless steel to keep them open). The solder must also fill the two holes at each end of the steam chest. It all seems a bit ''iffy'' hoping that the solder is going to find its way into all the holes and do the job. Is there some way that the holes could be plugged PRIOR to soldering the steam chest to the cylinder ?

Edited By Brian John on 05/08/2017 09:47:04

I found out today while in Coles Air Tools that they are an agent/distributor for Optimum lathes and mills. What SHOULD have happened when I ordered my lathe from Brisbane is that they should have immediately directed me to call Coles Air Tools to place the order. Had that happened, then none of this nonsense would ever have occurred. I would have just taken it back to the shop here in Cairns after the initial problems became evident and they would have sorted it out very quickly.....it is so frustrating to find this out now !

All that trouble because somebody did not follow correct procedure.

Edited By Brian John on 04/08/2017 12:17:17

A matchstick or some stainless steel ?: I have some 2.3mm stainless steel rod which fits nicely in the 2.5mm hole. I worry about timber igniting.

I finished the second cylinder today. Should the milled surface be touched up with a file or just leave it as is ?

I found that by drilling three 5mm X 2mm deep holes in the aluminium top plate that the screws on the mill slide could be more firmly located. This stops the cylinder pulling away from the vice. The two washers when held side by side measure 3.8mm so that gives me an idea when I am close to the required 4.0mm. There is no need to remove the work piece to measure it.

Edited By Brian John on 04/08/2017 10:14:02

I knew there was something else : there are two 2.5mm holes on the cylinder flat which mate up with two holes on the steam chest (24mm apart). I would think that these holes should not get blocked when soldering the two pieces together. The instructions mention nothing about this. What could be placed in the holes to be removed later in order to avoid these holes being clogged with solder : timber, aluminium wire, stainless steel wire ?

We have discussed the use of solder paste before : to join the steam chest to the milled flat on the cylinder as per the instructions. What temperature solder paste should be used ? Most of the solder pastes on the market seem to be for electrical work so I think it would be unsuitable for engineering.

I am also thinking of fluxing both sides, put some 243 degree soft solder between the pieces like a ''solder sandwich'' then apply heat. The only problem might be stopping the top piece from sliding about once things become hot and fluid. 

NOTE : I did buy some solder paste from the US months ago but I lost it in the shift to the new house !

Edited By Brian John on 02/08/2017 01:31:28

The first milled cylinder is on the previous page (8).

I seem to be limited to cuts of 0.25mm on my machine. What size cuts on brass could be taken on a decent size lathe, say a Sieg C3 ?

Edited By Brian John on 01/08/2017 14:20:57