Robs Mastiff

[RobC]

Its always exciting tracking an order you have been waiting weeks for it to dispatch....  Although at 14.2 kg not sure I anticipated such a heavy parcel between the UK and Australia, freight costs were very reasonable.     Am eagerly awaiting the casting (& stock) to see if this is as big as the weight suggests.  Although a build log maybe a little premature as this is a retirement project for future-me,  but lets at least set the delivery date to kick off the acquisition of parts.    Although I am sure we all have castings 10 years plus sitting around on the pretext of that will make a great retirement project one day !.

[Jo]

Although I am sure you all have castings 10 years plus sitting around on the pretext of that will make a great retirement project one day !.

One cannot have too many castings  They only go up in price and it is important to remember that you have to live as long as it take to make all the model engines in your stash. 

I think most of the weight in your set of Mastiff castings is the bar stock to make the bits out of.

Jo

[Sanjay F]

Although I am sure you all have castings 10 years plus sitting around on the pretext of that will make a great retirement project one day !.

I haven't been working on model engines for 10 yrs ............yet! I know of at least 1 set of castings I have that have passed via 2 engineers without being touched ....... I'm not going to let that happen .........but do remind me in 10 years 

[RobC]

Hemingway delivery arrived today.  Freight costs for Fedex was great considering the weight and size being packed well.   Very glad I purchased the complete kit however will probably be easier to make some parts from billet.  i.e. manifolds or cylinder covers as too difficult if I wanted a good surface finish around those 9 boss.  Easier to just machine this on the Mill or CNC router.
I better understand now that the kit can be lathe only manufacture,  so the casting kits are a great way to go using a 4 jaw and fly cutter with the casting mounted to the cross slide.  i think a Mill with a DRO will make it easier in 2025 than in 1973 when they produced the engine plans and ME articles.
Having never seen the actual plans I didn't realise it uses bronze bushing and not bearings (and O rings) , which is OK but assumed different.
I am used to Howell plans taking measurements from center lines,  Castings put a different view as measurements are from an various edges. Suppose alot eaaier to markout but with DRO I have multiple datums to set.
Looks like the engine itself is a lot less forgiving in terms of dimensioning than my current project -Howell V4.


I am pleased in not having to source materials as the time and expense does mount up.  In Australia we have to procure from lots of different suppliers around the country so freight costs do add up over the build.  At least this way I pay once and get 95% of the parts.  Now to get some bolts and spark plugs to complete the kit.

If anyone has a list of screws and sizes for a Mastiff that would be helpful,  but I will go through the plans and see if I can get a fastener list sorted

[Sanjay F]

That looks a beast of a project, I particularly like the pieces which look like giant Lego! 

I'll be wathcing along with your build, good luck.....

[Roger B]

That look's a fun project   

[deltatango]

Hi Rob,

It's good to see the bits have arrived! Sorry but I didn't write a list of fasteners, just made it up as I went along with Mastiff.

David

[RobC]

Picked up a radiator (used for a PC CPU cooling system) for the Mastiff and based upon the scale hoping it will fit well with the size and requirements of the engine.  Not quite sure how to incorporate it into the cooling system as Im missing a reservoir.   This radiator has two separate lower tanks, thus water flows up through one side then across the top and down to the other outlet.  I looked to make sure the radiator is made out of Brass tanks with copper fins, instead of the common aluminum body ones.  At least with brass top tanks I can maybe add an additional top tank over the top of the existing one to increase volume and add filler.

I understand the Mastiff does not have a water pump however relies on convection for water circulation.  Think I might get a small DC water pump to circulate the water to get it running and then later see how to adapt the water pump from the Jerry Howell V4 I am currently making.   Anyhow at AUD$50.00 plus $10 for a 100mm low profile PC fan unit think this will be a nice addition to the parts Im accumulating..   Happy to take comments if anyone has used a small electric or mechanical water pump before, or adapted these types of radiators.   For the top tank addition I was thinking of cutting off the top of the existing tank, then with the new tank to be a slip fit over the sides of the upper tank and then use JBWeld to secure the top tank to the radiator, save the risk of melting the existing solder.

[Roger B]

I have used gear pumps as circulation pumps with Delrin gears in an aluminium housing. They need a bit of clearance as the Delrin expands more than the aluminium.

I modified a computer radiator with a filling stub epoxied in place. I have also made my own radiators but it is quite an effort.