Author Topic: MBI AHC Diesel  (Read 9316 times)

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
MBI AHC Diesel
« on: September 05, 2016, 07:54:58 AM »
Some of you who live over the pond will have heard of AHC (America’s Hobby Centre) for the rest of us it was founded in 1931 and was at one time one of the biggest names associated with Model Aircraft. Around 1945 they embarked on designing a new Diesel Engine called the AHC Diesel, which was originally designed by Bernie Winston. Though announced the project was never brought to market.

The project nearly made it into production as the company had made the dies and had cast 500 crankcases out of “slag” (a cheap material not of the highest quality). We still do not know why it never came to market but finally one crankcase dated Jan 24 1977 and the remains of the drawings arrived in the hands of Ron Chernich. Ron with help from Ken Croft and David Owen set about redesigning and drawing up the engine in CAD.

The boys had a few crank cases cast and Bert Striegler built the prototype engine. There were early plans to make this a production engine but it was not to be....The intent had been to split the project three ways with parts going to Australia, Canada and England.

I know that the Australian third is with Ron’s estate, I do not know of the where abouts of the Canadian parts but I know of the location of at least one of the crankcases from the English set: it is sitting on my Dining table  ;D

Jo

P.S. The two variants “Red Racer and Black Magic” I have been told were caused by some of the Motor Boys having some fun   ::).
« Last Edit: September 05, 2016, 09:38:26 PM by Jo »
Enjoyment is more important than achievement.

Offline Dave Otto

  • Full Member
  • *****
  • Posts: 4693
  • Boise, Idaho USA
    • Photo Bucket
Re: MBI AHC Diesel
« Reply #1 on: September 05, 2016, 04:18:26 PM »
Interesting history Jo; is this one next in line after the triples?

Dave

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #2 on: September 05, 2016, 05:40:16 PM »
Interesting history Jo; is this one next in line after the triples?
Dave

Yes Dave that's the plan I need something simple after my Orphans and this cutie looks ideal, it will be my first ever Diesel  :embarassed:

The only down side is where this was supposed to be an international team build the crankcase machining is nearly finished. All that fun trying to work out how to hold the casting to machine each stage is already done  :'(

I do have a few photo's of the crankcase being machined: just it is not my work  :-[

Jo
« Last Edit: September 05, 2016, 05:45:10 PM by Jo »
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #3 on: September 05, 2016, 05:57:16 PM »
Can't your supplier give you a virgin casting out of that box full?

Are you going for the jam jar tank or that plastic jobbie?

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #4 on: September 05, 2016, 06:08:58 PM »
No they have all been machined now  :(

If I can find a suitable jar I would use it otherwise it will be a case of running the fuel line up onto the bottom of the carb  ;).

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #5 on: September 05, 2016, 06:23:40 PM »
What size does it need to be? looks about 25-30mm based on the bore

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #6 on: September 05, 2016, 06:36:33 PM »
25mm is the maximum for the fuel tank or it will hit the back of the crankcase cover  :-\

Jo
Enjoyment is more important than achievement.

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #7 on: September 05, 2016, 09:43:28 PM »
Can't your supplier give you a virgin casting out of that box full?

That was around the turn of the Millennium, this is the remains of the UK casting sets and by all accounts there was orders for about 20 of them (clearly now only 19  :naughty: )

Jo
Enjoyment is more important than achievement.

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #8 on: September 08, 2016, 06:38:18 PM »
I've been a little for a couple of days which has meant that it is best I lay off the triples just in case it goes wrong.

I find the best cure for any ills is to make swarf  ::) 

Jo
Enjoyment is more important than achievement.

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #9 on: September 20, 2016, 07:39:59 PM »
Having looked at the Orphans and found a feature that made me go  :Doh: I decided a bit of easy swarf making was in order  :naughty:

Did I mention never trust the drawings  ::) the thread in the top of the crankcase was not 20mm 32tpi as shown on the drawing :ShakeHead: it was 26tpi and just under 19mm  :headscratch:

Having done that I felt much better and realised that the Orphan's feature was not what it seemed  :) I may go back to them now that I have practised cutting a 26tpi thread  :paranoia:

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #10 on: September 20, 2016, 07:50:02 PM »
Was it the drawing that was wrong or had the previous builder deviated from what was on the drawing? Sounds a bit like somebody had a 3/4" x 26 tap handy

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #11 on: September 20, 2016, 08:04:23 PM »
The UK casting hoarder supplier had a 3/4 26tpi tap to hand when he originally cut them. Luckily he did mention to check first as his memory was going ::)

Jo
Enjoyment is more important than achievement.

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #12 on: September 21, 2016, 01:21:20 PM »
 :paranoia: No, no, no that square thread still looks tricky.....

Milling the ports in the liner was interesting  ::) The liner is a bit twee as are the milling bits to mill the ports. I ended up having o pull the liner a fair bit out of the indexing head and providing tailstock support. The good news is that the holes seem to line up on the casting  ;D

The Contra piston looks interesting (much more interesting than cutting two start threads  :naughty:) but I am not sure how you are supposed to hold it to hone the outside...maybe superglue  :noidea:

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #13 on: September 21, 2016, 01:29:53 PM »
Bore the end of the contra piston on the end of a piece of rod, hone to a tight fit and then part off simples

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #14 on: September 21, 2016, 01:34:44 PM »
 :thinking: Which means I need to get Smelly set up to hone the liner in the not too distant future.

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #15 on: September 21, 2016, 01:43:01 PM »
:thinking: Which means I need to get Smelly set up to hone the liner in the not too distant future.

Jo

But not until you have cut those reverser threads :LittleDevil:

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #16 on: January 20, 2017, 08:31:50 AM »
A last couple of shots: The engine parts and the finished engine  ;D

I can report that the engine is nice and bouncy. But running will have to wait until I have a suitable backup crew available (with a fresh thumb to entice the engine into running  :naughty:  )

Jo
Enjoyment is more important than achievement.

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: MBI AHC Diesel
« Reply #17 on: January 20, 2017, 11:21:30 AM »
Looking good Jo - eagerly awaiting a video of it running   :Love:

While it's not exactly pleasent when your finger is hit by the prop - you could use a starting stick  ;)

Offline steve-de24

  • Full Member
  • ****
  • Posts: 141
Re: MBI AHC Diesel
« Reply #18 on: January 20, 2017, 01:28:26 PM »
Jo, a nice looking engine, and inspiration for my Midge build that is proceeding slowly. I like the streamlined prop nut and I'm thinking that something similar would look rather good on my Midge. I'd love to see a pic of your engine running.
Steve

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #19 on: January 20, 2017, 01:33:12 PM »
Talking of prop nuts would it be prudent to drill & tap the end for a lock screw as we would not want the prop chasing Eric down your garden in tHE event of a backfire.

Still think a flywheel weight would allow you to test run these relatively safely on your own

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #20 on: January 20, 2017, 02:16:14 PM »
Eric doesn't want to play pit crew any more  :disappointed: I will need to find myself another man  :-\

The problem with a flywheel is that it does not increase the force needed to rotate it at speed like a prop does. And it looks like I don't have a wooden prop of the right size  :(

Jo
Enjoyment is more important than achievement.

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #21 on: April 05, 2018, 04:09:57 PM »
No thumbs were harmed in the making of these videos  :ThumbsUp:

<a href="https://www.youtube.com/watch?v=g33tPBGV-cA" target="_blank">http://www.youtube.com/watch?v=g33tPBGV-cA</a>

Then we tried a different prop to see if that could attract a thumb :naughty:

<a href="https://www.youtube.com/watch?v=CJoDVXcslKY" target="_blank">http://www.youtube.com/watch?v=CJoDVXcslKY</a>

Sadly this was the only engine run today due to too much yaking and tea drinking :disappointed:

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9466
  • Surrey, UK
Re: MBI AHC Diesel
« Reply #22 on: April 05, 2018, 04:15:33 PM »
Sweet :)

The new camera also takes decent length videos ;)

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: MBI AHC Diesel
« Reply #23 on: April 05, 2018, 04:47:53 PM »
A fine runner  :praise2: and it sounds good too  :ThumbsUp:

I'm sligthly surpriced that it didn't run faster, but then again - it is the first run, isn't it - so I'm sure that (is it Eric) did not lean it out as it is very much in the run in / break in period.

Thank you for showing us Jo.

Offline mikecole7

  • Full Member
  • ****
  • Posts: 43
Re: MBI AHC Diesel
« Reply #24 on: April 05, 2018, 07:24:32 PM »
     
       Well done Jo, it runs great.  Eric can sort these engines out.   Well done.

       Mike

Offline b.lindsey

  • Global Moderator
  • Full Member
  • *****
  • Posts: 13860
  • Dallas, NC, USA
    • Workbench-Miniatures
Re: MBI AHC Diesel
« Reply #25 on: April 05, 2018, 07:42:11 PM »
Good looking engine and a very nice runner Jo!!

Bill

Offline tangler

  • Full Member
  • ****
  • Posts: 834
  • Christchurch, UK
Re: MBI AHC Diesel
« Reply #26 on: April 05, 2018, 08:45:49 PM »
Brill.  :cartwheel:

Rod

Offline Dave Otto

  • Full Member
  • *****
  • Posts: 4693
  • Boise, Idaho USA
    • Photo Bucket
Re: MBI AHC Diesel
« Reply #27 on: April 06, 2018, 01:07:07 AM »
Congrats on a runner Jo!
It sounds nice.


Dave

Offline Art K

  • Full Member
  • ****
  • Posts: 1761
  • Madison, Wisconsin USA
Re: MBI AHC Diesel
« Reply #28 on: April 06, 2018, 02:20:11 AM »
Sounds great Jo! Glad to hear that no thumbs were injured during this filming. :ROFL:
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #29 on: April 06, 2018, 05:00:22 AM »
Thanks Guys  :)

Well done Jo, it runs great.  Eric can sort these engines out.

As Eric says: I need a younger man :embarassed: Mike, someone who is less interested in sitting round, drinking tea and yaking about what's wrong in the world and more motivated in actually doing things. But where are the youngsters (even those under 60) in this hobby? Model engine making is in danger of dieing out  :toilet_claw: 


Jo
Enjoyment is more important than achievement.

Offline Roger B

  • Global Moderator
  • Full Member
  • *****
  • Posts: 6133
  • Switzerland
Re: MBI AHC Diesel
« Reply #30 on: April 06, 2018, 09:29:19 AM »
Excellent runner, well done  :praise2:  :praise2:  :wine1: Where's all the snow gone?  :stir:
Best regards

Roger

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #31 on: April 06, 2018, 09:39:41 AM »
Thanks Roger  :)

Where's all the snow gone?  :stir:

Dave was looking after it for me earlier in the week  :naughty:

Jo
Enjoyment is more important than achievement.

Offline Bluechip

  • Full Member
  • ****
  • Posts: 1007
  • Derbyshire
Re: MBI AHC Diesel
« Reply #32 on: April 06, 2018, 10:10:07 AM »
Thanks Roger  :)

Where's all the snow gone?  :stir:

Dave was looking after it for me earlier in the week  :naughty:

Jo

Which Dave ???

Dave


Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15294
  • Hampshire, england.
Re: MBI AHC Diesel
« Reply #33 on: April 06, 2018, 10:13:05 AM »
Which Dave ???

YOU ! It was your excuse for not getting out in the garden :lolb:

Jo
Enjoyment is more important than achievement.

Offline Bluechip

  • Full Member
  • ****
  • Posts: 1007
  • Derbyshire
Re: MBI AHC Diesel
« Reply #34 on: April 06, 2018, 10:41:31 AM »


YOU ! It was your excuse for not getting out in the garden :lolb:

Jo

Oh!    :headscratch:   Long time ago, more than 20 minutes.   Forgotten about that ...  :old:

Anyway, some of us poor souls live somewhat further away from the Equator than others .....   :(
Gets a bit nippy around the wotsits up here.
In that sort of weather it's better that we retired gentlefolk stay close to the central heating and observe the antics of others through the double glazing ....   :stir:

Dave





Offline Stuart

  • Full Member
  • ****
  • Posts: 1785
  • Tilchestune UK
Re: MBI AHC Diesel
« Reply #35 on: April 06, 2018, 10:45:27 AM »
Dave
I just send Linda out to do the gardening😂 then I get a rest from the vacuum cleaner

Stuart
My aim is for a accurate part with a good finish

Offline michaelr

  • Full Member
  • ****
  • Posts: 163
Re: MBI AHC Diesel
« Reply #36 on: April 06, 2018, 07:41:59 PM »
Jo. Jason mentioned using a flywheel instead of a prop for running your engines and he has got a point, I ran a ED Racer, ED Sea Otter, and a 15cc Gannet OHV when I was into model boats all started and ran no bother.
With test bed running you could use a electric starter and not be bothered with a starting cord, the only thing would maybe be a cooling issue but worth a try.

Mike.

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal