Author Topic: Bengs, Flame Eater. "Nick".........  (Read 22736 times)

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #30 on: June 12, 2014, 09:15:03 AM »
Hugh.
I think we're slightly at cross purposes......
I'm grumbling at the mass of plumbers solder. Would have been a lot neater, using electical solder!  ::)

Ian.
I'm happy and settled with the stove rope, in it's various diameters to suit differing situations.
But, your previous postings made me have to experiment.  ;)
I've just ordered a bundle of 32gauge florist's wire........


The engine's all held together with M2 threads, having 3mm a/f nuts. The same as the socket in an M4 caphead.  ;)

Reduced the head diameter as far as sensible. Then drilled 2mm x 1/4" deep, to clear the longer thread.

Couple of locked nuts, for a handle........




Works a treat!

Not happy with the lack of "compression". No head/ cyl seal, won't help!  ::)

The slot for the poppin up n down valve, seems to be a bit deep. At 10thou clearance.......




Gave everything a rub on fine emery. Reducing slot depth, to give 5thou clearance.......




All back together now. Awaiting the chance to give it a run......  :D

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #31 on: June 13, 2014, 09:11:11 PM »
And......
The run didn't go well. Stopping every few seconds. :ShakeHead:

I realised, the engine didn't spin over, as it had done previously. Possibly out of alignment, after I had tightened all the loose nuts?  :thinking:

Time to strip further!

Piston. Scuffed one one side. With what looks like ptfe tape packing.........




That's not original, surely? Made from 16mm bar. Not machined on the o/d.........




Looks like the oiler insert was a bit long. And held fine bits of swarf..........




Better  view. Bore is badly scuffed, on the other side to the oiler........




Time for a rebore.........




And hone........




Sheesh!  :shrug:

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

fcheslop

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Re: Bengs, Flame Eater. "Nick".........
« Reply #32 on: June 13, 2014, 10:33:25 PM »
Hi David, that piston just dont look right
Thanks for the call
cheers

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #33 on: June 13, 2014, 10:38:08 PM »
Hi David, that piston just dont look right
Thanks for the call
cheers

Frazer.

Yer right. It don't! But. It will.......  ;)

No problem Marra.  ^-^

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline Ian S C

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Re: Bengs, Flame Eater. "Nick".........
« Reply #34 on: June 14, 2014, 11:43:33 AM »
David, did the piston have packing originally?  I would have thought that the packing would be a source of friction, and PTFE expands on heating.  My flame licker has a steel bore, and cast iron piston, no packing, or rings, and just able to slide down the bore under its own weight.
       The scoring on the cylinder/ piston might relate to running two like metals together, which is a no no unless it is cast iron.        Ian S C

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #35 on: June 15, 2014, 10:58:57 PM »
Ian.
The bottom of the piston groove has multiple scratches, across it's whole circumference. As though someone has dug out the original packing ring.
But, what the packing was, is anyone's guess......  :thinking:

I was going to replace the piston with another brass one. But have steel, cast iron, aluminium, and graphite in stock. Any suggestions as to what to use?  ;)

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

fcheslop

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Re: Bengs, Flame Eater. "Nick".........
« Reply #36 on: June 15, 2014, 11:02:49 PM »
Dont like the horrible dirty stuff but Graphite or cast maybe a good choice :ThumbsUp:
Had a look on Bengs no mention of a sealing ring :shrug:
cheers

Offline fumopuc

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Re: Bengs, Flame Eater. "Nick".........
« Reply #37 on: June 16, 2014, 04:40:59 AM »
Ian.
The bottom of the piston groove has multiple scratches, across it's whole circumference. As though someone has dug out the original packing ring.
But, what the packing was, is anyone's guess......  :thinking:

I was going to replace the piston with another brass one. But have steel, cast iron, aluminium, and graphite in stock. Any suggestions as to what to use?  ;)

David D

Hi David, most of the Bengs (Flammenfresser) flamelicker are running with graphite pistons. Absolutely dry, no oil.
When I have build my engine some years ago, I have made the mistake that some oil find the way into the cylinder. After making a new piston everything was fine.
Kind Regards
Achim

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #38 on: June 16, 2014, 09:25:22 AM »
Frazer, Achim.
Thanks Fellas!  :ThumbsUp:

Looks like, the best pistons are made from mucky stuff........  :(

Hope Mrs. Drillin doesn't notice the footprints. This time!  ;)

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

Offline fumopuc

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Re: Bengs, Flame Eater. "Nick".........
« Reply #39 on: June 16, 2014, 12:30:50 PM »
Hi David, I have used my shop vacuum cleaner directly at the lathe near the cutting tool. So there was no dust flying around.
« Last Edit: June 16, 2014, 03:46:38 PM by fumopuc »
Kind Regards
Achim

Offline Ian S C

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Re: Bengs, Flame Eater. "Nick".........
« Reply #40 on: June 16, 2014, 03:39:06 PM »
David, I think the Graphite is about the best choice you have there.  The bore must be polished, then the piston turned to just about size, then polished down by wrapping a bit of plain paper around it (still in the lathe), just hold it as you would a bit of abrasive cloth.
     DO NOT GET OIL ON IT.  I'v never used a graphite piston, but it should give good service in a polished bore.
     Graphite pistons in glass cylinders are used as door closers, in the likes of commercial buildings.  At one time they were available as free samples from the manufacturers if you lived in USA.         Ian S C

fcheslop

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Re: Bengs, Flame Eater. "Nick".........
« Reply #41 on: June 16, 2014, 05:04:53 PM »
Have you been chatting to our lass .Not only the black foot prints but grubby black marks on the bog seat :naughty: and doors.
A vac is good but not the house one :facepalm: boy was I in bother again not an unusual event round here.
I machine em exactly as Ian describes
cheers

Online Stilldrillin

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Re: Bengs, Flame Eater. "Nick".........
« Reply #42 on: June 16, 2014, 09:53:11 PM »
Hi David, I have used my shop vacuum cleaner directly at the lathe near the cutting tool. So there was no dust flying around.

Good idea, Achim!  :ThumbsUp:

David, I think the Graphite is about the best choice you have there.  The bore must be polished, then the piston turned to just about size, then polished down by wrapping a bit of plain paper around it (still in the lathe), just hold it as you would a bit of abrasive cloth.
    DO NOT GET OIL ON IT.  I'v never used a graphite piston, but it should give good service in a polished bore.
     Graphite pistons in glass cylinders are used as door closers, in the likes of commercial buildings.  At one time they were available as free samples from the manufacturers if you lived in USA.         Ian S C

Ian.
Needing a polished bore, and your warning about oil........  :-\

I'm thinking about it's later life. Cos, I'm reliably informed, it's going to Norway. When I'm done with it.  :shrug:

Might go with c/i. Or, not.......  :headscratch:


Anyroad! Here's a pic for you........




32 gauge florist's wire. Seems to work well!  :)

Frazer.
Yer a braver, (or more foolhardy), man than me........  :ShakeHead:

David D
David.
Still modifying bits of metal... Occasionally, making an improvement!
Still drilling holes... Sometimes, in the right place!

fcheslop

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Re: Bengs, Flame Eater. "Nick".........
« Reply #43 on: June 16, 2014, 10:34:18 PM »
 :lolb:wor lass knows by now,Then she shouts youre not coming near me with  :naughty:

fcheslop

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Re: Bengs, Flame Eater. "Nick".........
« Reply #44 on: June 16, 2014, 10:35:33 PM »
Whats in the Aldi box owt interesting :stir: