My 11 year old grandson and I have assembled it our MM-5, following
yor instructions closely, and were delighted to to find that it ran
excellently- more than ten minutes on a mug of hot water and for
nearly that in reverse on a pack of frozen peas!
Two points: 1. The brass bush holding the propeller is rather weak.
I was a trifle heavy-handed as the acorn nut holding did not seem to
be a good mate on the bush thread. The threaded portion sheared off.
It might be worth emphasising that the threaded section is hollow for
the crankshaft and therefore the neck is very thin. Do not over
tighten! Problem fixed with SuperGlue.
2. The rubber tubes are fine but a technique has to be learned to
folded over the ends as described. After a lot of fiddling I found
that if I slipped the steel rod (end of the crankshaft) AND the little
hex wrench together into the rubber tube it was easier to get the fold
over started.
thanks for a very intriguing and instructive little engine. Best
wishes, L.J. (Jim) Smith Birdlip, Glos. U.K.
[This was re-posted from an e-mail we received]
Assembly tips for MM-5
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-
marcus_dds
- Posts: 1
- Joined: Sun May 26, 2002 2:22 am
- First Name: Marcus
- Last Name: de Deus Silva
Response to Assembly tips for MM-5
The kit was straight forward to build and the
instructions were easy to follow, even though I don't
consider myself to be that practically minded.
The main fiddly part was folding over ends of the rubber
tube connecting rods to make the "socks." This took
some time. In the end, I realised that the trick is
that the rubber is very tough and not worry about over
stretching or breaking it whilst trying to fold the
ends over (using fingers only).
The only other problem I had was that, the first time
I ran the engine, it only ran for about 3 minutes and
then, the second time, hardly at all, perhaps just
seconds. Anyway I followed the instructions, tried the
compression test which failed, checked and reassambled
the diaphram piston assembly (no damage to the
diaphram) and then rechecked the compression which
still was not right. I then re-glued the bottom
cylinder cap; it was still well attached but I
suspected that I had not used enough epoxy. This meant
however that the transparent cylinder got messed up
with epoxy whilst filling in the gap around the inside
of the cylinder cap. However after wiping off the
excess it did not not look too bad. Since then the
motor has worked very well every time.
instructions were easy to follow, even though I don't
consider myself to be that practically minded.
The main fiddly part was folding over ends of the rubber
tube connecting rods to make the "socks." This took
some time. In the end, I realised that the trick is
that the rubber is very tough and not worry about over
stretching or breaking it whilst trying to fold the
ends over (using fingers only).
The only other problem I had was that, the first time
I ran the engine, it only ran for about 3 minutes and
then, the second time, hardly at all, perhaps just
seconds. Anyway I followed the instructions, tried the
compression test which failed, checked and reassambled
the diaphram piston assembly (no damage to the
diaphram) and then rechecked the compression which
still was not right. I then re-glued the bottom
cylinder cap; it was still well attached but I
suspected that I had not used enough epoxy. This meant
however that the transparent cylinder got messed up
with epoxy whilst filling in the gap around the inside
of the cylinder cap. However after wiping off the
excess it did not not look too bad. Since then the
motor has worked very well every time.
"Roll Sock"
From a customer who had difficulty making the roll sock.
######-
I found putting the tubing on the provided allen
wrench and rolling it on that easier. Once rolled I move it to the required
part.
Thanks,
Jerry Sartori
Comments from Brent:
#######
This process might be made easier if you clean the
tubing and your fingers off with rubbing alcohol first.
The tubing can also be glued to the shaft with superglue (but make sure it's in the right spot first). Tape can also be used as a temporary (or permanent) fastener.
######-
I found putting the tubing on the provided allen
wrench and rolling it on that easier. Once rolled I move it to the required
part.
Thanks,
Jerry Sartori
Comments from Brent:
#######
This process might be made easier if you clean the
tubing and your fingers off with rubbing alcohol first.
The tubing can also be glued to the shaft with superglue (but make sure it's in the right spot first). Tape can also be used as a temporary (or permanent) fastener.
How I got a MM-5 to run on the heat of my hand
When I had the engine running on the heat of my hand, the room was around 18-20 degrees centigrade (The central heating thermostat is set to 20 )
I ordered the kit via the web and was promised delivery within ten days butas this was over the Christmas holidays I assumed a longer delivery time because of the seasonal postal rush. Exactly ten days after placing the order my kit arrived in the UK. First impressions were of a very high quality item, well packed and all parts present when checked off against the parts list.
I spent some time reading the instructions and checked I had all the tools required for the kit assembly. The tools are just an allen key (supplied in the kit) one socket (8mm or 5/16"), silicone glue and super glue. I decided to change the assembly order and method, not because there was anything wrong or difficult about the manufacturer's method but just that I thought I could make a small improvement.
One of the crucial stages in the assembly is getting the Cylinder Ring
concentric to the Displacer Rod bearing. The instructions recommend fitting the Displacer into the bearing, drawing round the Displacer and using this pencil mark to align the Cylinder Ring when glued to the base. I thought if I had a more "engineered method " I could get a better result. A piece of MDF [particle board] 12mm thick and 4" square had a hole 6mm diameter drilled in the middle at the intersections of pencil drawn diagonals. This was now fitted in a 6mm diameter mandrel in the lathe and the O/D turned to 94mm to be a loose sliding fit in the Cylinder Ring. A shallow shoulder was also machined 3mm long and down to 75mm diameter. This is to give clearance to the base of the
Cylinder Ring and so that any sealer, which squeezes out from the base of the Cylinder Ring won't also glue the MDF to the engine. A short 6mm dia. MS bar was turned down to 0.094" (the bore of the crankcase brass shoulder)
Now the assembly could start! I used silicone sealer to attach the Cylinder Ring to the main engine base. The instructions recommend either silicone sealer or Araldite but I feel that silicone is the only choice for this part of the assembly. The Cylinder Ring was slid onto the MDF disk and silicone sealer smeared around the edge of the Ring. Carefully avoiding getting any sealer on the MDF the Cylinder Ring was now placed on the engine base and left for 12 hours to set. I know this is a long time but I was in no hurry. The MDF disk came away cleanly after the sealer had set and although some sealer had oozed inside the Cylinder Ring none had stuck to the MDF disk because of the clearance made by the shoulder.
The next stage was to fit the short brass tube into the crankcase bush. This is the first part to be assembled when following the manufacturer's instructions. I used the MDF disk with a layer of paper on it to give a flat surface inside the Cylinder Ring to ensure that the rod was flush with the underside of the crankcase.
At the next stage where the Displacer Rod is fitted to the Displacer Plug I again used the lathe. This time the Displacer Rod was gripped in the lathe chuck first having a piece of paper wrapped around it to prevent the Displacer Rod being marked. The Displacer Plug was then pushed onto the Displacer Rod using the lathe tailstock barrel.
>From this stage on the assembly was exactly as recommended by the
manufacturers, the only difficult part being the fitting of the rubber tube to the various rods but this has been found difficult by other builders as well. All in all a very worthwhile kit for both building and running.
This was sent to us by Alistair Grant, Carnoustie, Scotland.
I ordered the kit via the web and was promised delivery within ten days butas this was over the Christmas holidays I assumed a longer delivery time because of the seasonal postal rush. Exactly ten days after placing the order my kit arrived in the UK. First impressions were of a very high quality item, well packed and all parts present when checked off against the parts list.
I spent some time reading the instructions and checked I had all the tools required for the kit assembly. The tools are just an allen key (supplied in the kit) one socket (8mm or 5/16"), silicone glue and super glue. I decided to change the assembly order and method, not because there was anything wrong or difficult about the manufacturer's method but just that I thought I could make a small improvement.
One of the crucial stages in the assembly is getting the Cylinder Ring
concentric to the Displacer Rod bearing. The instructions recommend fitting the Displacer into the bearing, drawing round the Displacer and using this pencil mark to align the Cylinder Ring when glued to the base. I thought if I had a more "engineered method " I could get a better result. A piece of MDF [particle board] 12mm thick and 4" square had a hole 6mm diameter drilled in the middle at the intersections of pencil drawn diagonals. This was now fitted in a 6mm diameter mandrel in the lathe and the O/D turned to 94mm to be a loose sliding fit in the Cylinder Ring. A shallow shoulder was also machined 3mm long and down to 75mm diameter. This is to give clearance to the base of the
Cylinder Ring and so that any sealer, which squeezes out from the base of the Cylinder Ring won't also glue the MDF to the engine. A short 6mm dia. MS bar was turned down to 0.094" (the bore of the crankcase brass shoulder)
Now the assembly could start! I used silicone sealer to attach the Cylinder Ring to the main engine base. The instructions recommend either silicone sealer or Araldite but I feel that silicone is the only choice for this part of the assembly. The Cylinder Ring was slid onto the MDF disk and silicone sealer smeared around the edge of the Ring. Carefully avoiding getting any sealer on the MDF the Cylinder Ring was now placed on the engine base and left for 12 hours to set. I know this is a long time but I was in no hurry. The MDF disk came away cleanly after the sealer had set and although some sealer had oozed inside the Cylinder Ring none had stuck to the MDF disk because of the clearance made by the shoulder.
The next stage was to fit the short brass tube into the crankcase bush. This is the first part to be assembled when following the manufacturer's instructions. I used the MDF disk with a layer of paper on it to give a flat surface inside the Cylinder Ring to ensure that the rod was flush with the underside of the crankcase.
At the next stage where the Displacer Rod is fitted to the Displacer Plug I again used the lathe. This time the Displacer Rod was gripped in the lathe chuck first having a piece of paper wrapped around it to prevent the Displacer Rod being marked. The Displacer Plug was then pushed onto the Displacer Rod using the lathe tailstock barrel.
>From this stage on the assembly was exactly as recommended by the
manufacturers, the only difficult part being the fitting of the rubber tube to the various rods but this has been found difficult by other builders as well. All in all a very worthwhile kit for both building and running.
This was sent to us by Alistair Grant, Carnoustie, Scotland.
Cylinder Alignment Tool
Alistair Grant sent us this picture of the alignment tool that he built. We use something similar at the factory when we build ready to run engines.
-
amstirling
- Posts: 1
- Joined: Fri Nov 21, 2003 1:09 pm
- First Name: Robert
- Last Name: West
Ran 75 minutes first try
My kit ran 75 minutes on the first try. It's a very thought-provoking kit. I built my kit carefully, and it probably helped that I have a lot of mechanical experience.
Some notes: I would suggest really encouraging visitors to the website to read the directions. I had dismissed the kit as too expensive for what it is, and I imagine a lot of others do too- until I read through the instructions and started to get a feel for what went into it, and how much of that work I didn't want to duplicate myself, at least for a first try.
The directions are very good. Some minor pitfalls, both avoided and not: I did have to "cuff" the elastic tubing to get it to grip the connecting rods properly- it was too loose otherwise, slipped right off. I found that shoving a round tapered wooden toothpick into the ends made it much easier to do that. I did a lot of detail work, polishing the bearing areas of the crankshaft, chamfering the rod bearings to reduce the bearing surface, etc. Don't know that it really made much difference. I did have to ream out the hole in the propellor a bit- it just wasn't going on the "reducer". On the third or fourth run, I got a little carried away with experimentation and let it get too hot (on a gradually warming.. not hot.. wood stove). No parts were damaged, but the air seal was lost, either from the silicone melting or the expansion of the baseplate breaking the seal, don't know. Since I had used silicone and not epoxy, it was at least possible to pull it apart and redo. Took awhile to make it neat, the second time. It might be worth including a warning about too much heat- which, at least with the silicone, seems to be far short of the heat needed to actually damage components. Seems like black would be far more efficient than blue and red- but then, it might be far less marketable. I might try adding a surplus computer-CPU heatsink to the top. Watching it run, you can't help but think about possibilities...
Some notes: I would suggest really encouraging visitors to the website to read the directions. I had dismissed the kit as too expensive for what it is, and I imagine a lot of others do too- until I read through the instructions and started to get a feel for what went into it, and how much of that work I didn't want to duplicate myself, at least for a first try.
The directions are very good. Some minor pitfalls, both avoided and not: I did have to "cuff" the elastic tubing to get it to grip the connecting rods properly- it was too loose otherwise, slipped right off. I found that shoving a round tapered wooden toothpick into the ends made it much easier to do that. I did a lot of detail work, polishing the bearing areas of the crankshaft, chamfering the rod bearings to reduce the bearing surface, etc. Don't know that it really made much difference. I did have to ream out the hole in the propellor a bit- it just wasn't going on the "reducer". On the third or fourth run, I got a little carried away with experimentation and let it get too hot (on a gradually warming.. not hot.. wood stove). No parts were damaged, but the air seal was lost, either from the silicone melting or the expansion of the baseplate breaking the seal, don't know. Since I had used silicone and not epoxy, it was at least possible to pull it apart and redo. Took awhile to make it neat, the second time. It might be worth including a warning about too much heat- which, at least with the silicone, seems to be far short of the heat needed to actually damage components. Seems like black would be far more efficient than blue and red- but then, it might be far less marketable. I might try adding a surplus computer-CPU heatsink to the top. Watching it run, you can't help but think about possibilities...
Response to Assembly tips for MM-5
The kit was very easy to put together. Only minimal modifications were needed. It ran after the first spin for 45 minutes, the water in my coffee mug had cooled off. I replenished the hot water and it is off and running now.
I also notice it does not run at a constant rate but speeds up and slows down from time to time. Next I will try the ice chip heat sink trick after it stops... Thanks to previous kit builder MJclimber for the hint on bending the crankcase flat. I also found the piston end plate fit flat in one position but not when rotated 90 degrees - the piston rim was not flat, so try rotating yours to find and then note the best fit before applying glue/sealant. I also needed to file the ends of all steel rods (crankshaft, upper piston rod, upper displacer rod, lower displacer rod, diaphragm rod) to remove burs. I added no oils for seals nor bearings. I found a good pair of small sharp crosscut pliers was the best tool to cut the rubber tubing, not a knife.
I am very impressed with the design and operation of this engine - if I can get my design to work this well then I can help us all to be one step closer to free ourselves from dependence on fossil fuels. -KO'M
I also notice it does not run at a constant rate but speeds up and slows down from time to time. Next I will try the ice chip heat sink trick after it stops... Thanks to previous kit builder MJclimber for the hint on bending the crankcase flat. I also found the piston end plate fit flat in one position but not when rotated 90 degrees - the piston rim was not flat, so try rotating yours to find and then note the best fit before applying glue/sealant. I also needed to file the ends of all steel rods (crankshaft, upper piston rod, upper displacer rod, lower displacer rod, diaphragm rod) to remove burs. I added no oils for seals nor bearings. I found a good pair of small sharp crosscut pliers was the best tool to cut the rubber tubing, not a knife.
I am very impressed with the design and operation of this engine - if I can get my design to work this well then I can help us all to be one step closer to free ourselves from dependence on fossil fuels. -KO'M
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rfrauenzimmer
- Posts: 1
- Joined: Thu Jul 28, 2005 11:26 am
- First Name: RICHARD
- Last Name: FRAUENZIMMER
Response to Assembly tips for MM-5
I used a differant glue to put my MM-5 together. I have been a modle sail boat racer for years. I have used "formula '560' canopy glue" by Pacer Technology for years to seal canopies & deck fitting on my sail boats. this is a water base material which beeds. It turn clear when dry, from an easy to see white. I didn't even have to use the circle drawing on the crankcase to get it to work. It also states on the lable it is extremely shock resistant. it sets in 3 hrs & fully cured in 24.
Good luck,
Rich Frauenzimmer
Good luck,
Rich Frauenzimmer