Saito Steam Engine

[derekwarner_decoy]

Hullo Calin......nice to hear from you...hope you are well 

The pressure gauge in the lubricator is to confirm to the scale engine/boiler room crew that forced pressure lubrication is available for the engine 

Have been working on the wheels...an old 1/3 finished set...manufactured new shafts other parts.......purchased a set of paddle blade cast brass supports from Manfred at Elde-Modellbau ...... M2 & M3 Hex Head brass bolts from KNUPFER & assembling with a swag of Chinese brass serrated nuts

Derek

[kno3]

Your paddlewheels are very detailed, nice!

[derekwarner_decoy]

More completed on the wheel sets ......

72 x M3 brass HPGS each end of converted to 1/16" diameter brass tie rods.....56mm long overall
72 x M3 brass insert nuts
144 x M3 brass washers

All assembled OK, however each wheel took a quite a few hours in the lathe to true up each assembly.......the hammering during the riveting process [36 x 1/16" rivets per wheel] created a little distortion of the arms & frames

I am undecided how to complete the final M3 insert nuts locking...will need to talk with Thomas to understand how he completed [grade of Loctite?] this with his Elde-Modellbau wheel set

I am needing to be cautious of the weight...[each wheel now calculated as ~~ 405gm]...so have ordered 36 x D1500-23 KSF e-clips for the actual 1/8" paddle shafts to position and lock against sideways movement [the KSF = bronze material]

So each wheel will comprise brass plate, bronze bolts, nuts & rivets, and Grade 316 main hubs & some M2 SS HPGS....

The 5/32" shafts grade Grade 304, the shaft beatings are 5/32" bore ZZ sealed stainless steel ball races in aluminium plummer blocks

Derek

[DamienG]

Very nice Derek.   

[Delaunay]

: D Good morning;
Beautiful work Derek: clap
Damage to the slight deformation of the sets: sobbing
cordially
François (pif in another place)

Bien l'bonjour ;
Magnifique travail Derek 
Dommage pour la légère déformation des ensembles
Cordialement
François ( pif dans un autre lieu )

[derekwarner_decoy]

Hullo and thankyou François........

Considering the amount of  required, I am happy with the squareness and parallelism of the 1/16" diameter tie rods

I am thinking of cutting some wooden spacers of identical length to use as jig spacers when I do the final tighten up of all of the 144 x M3 nuts prior to the Loctite process

Derek   

[dosteam1]

I have 2 questions for the Saito steam engine owner out there. I have a local that has a t2 for sale and i am curious if the torque figures for this and the more modern T2dr similar or is the older t2 considerably weaker? Also, do any of you saito owner also happens to own a tvr1a that is the other engine that I am debating if I should get over the Saito

[derekwarner_decoy]

Welcome to the Saito steam world..............[or limited documentation]

The Saito T2 engine is advertised as a 12 x 12 bore & stroke engine, designed for 2 Bar steam WP
Saito also produce a T2L which is a 12 x 20 bore & stroke also designed for 2 Bar stean pressure........

The former has 4 - M2 Brass bolts securing the valve plates
The later has 6 - M2 Brass bolts securing the valve plates

Specification, including torque figures, is available on the original Saito WEB page........

Regrettably, I have seen Saito T2 engines advertised as 20 mm stroke.......when if fact they were 12mm......

Read on & any further questions, don't hesitate to come back.........[I have no experience with the TRV1A engine]

Derek

[kno3]

I have 2 questions for the Saito steam engine owner out there. I have a local that has a t2 for sale and i am curious if the torque figures for this and the more modern T2dr similar or is the older t2 considerably weaker? Also, do any of you saito owner also happens to own a tvr1a that is the other engine that I am debating if I should get over the Saito

Hello, Saito T2 is a piston valve twin steam engine, recognizable by its green painted cylinders. It is no longer being made. The current model is the Saito T2DR, which is a slide valve twin engine. Both engines have identical bore and stroke, 12 mm and parts such as the crankshaft and the reversing gear seem identical too.

I don't think there's is a great difference in power, because of the identical bore and stroke.

I own all 3 engines you are asking about (Saito T2, T2DR and Graham TVR1A). All three are good, but in my opinion the T2DR is the nicest of all, because it looks very scale, it is made with very fine castings for the cylinders. The Saito engines run like swiss watches. The Graham, if it was a kit, the running qualitiss depend on the skill of the person who assembled it, but usually they run well too.

So it really is a matter of price and taste.

[dosteam1]

Wow, speedy response nice.  Is there a noticeable torque difference between the Graham and the Saito? I like the compact size and low weight of the Graham but if the power difference between the two is big enough I may have to go with the Saito. This will be powering a land vehicle where high rpm and torque are both kinda needed It will definitely be a runner no shelf queen.

[dosteam1]

Hi PD's......kno3.........here is a link to the boiler feed pump

http://www.ebay.com.au/itm/Microcosm-M5-Live-Steam-boiler-feed-pump-Twin-Cylinder-Steam-Engine-/151198790945?pt=AU_Toys_Hobbies_Powered_Toys&hash=item2334267521

It is 5 mm bore x short stroke of 6mm....the Saito paddle shaft is 4.0 mm OD....the Microcosm pump eccentric hub is also to suit 4.0 mm....

Interesting i finally jump the gun and bought a T2R and currently  considering a Microcosm m5 pump to, but still unsure if i should drive it from a an electric motor or from then engine itself don't want to rob to much power from the engine.

[derekwarner_decoy]

The only real disadvantage I see with driving a boiler water makeup piston pump directly from the engine crank, is that pump displacement is directly proportional to the engine speed

So some use an external needle valve to maintain a preset pump volume that is also set to exceed the boiler relief valve pressure setting

So the upshot of such difficult external needle valve set points, the pump is working to boiler relief valve load and dumping a large quantity of water overboard or back to your boiler water feed tank whenever the engine is running

The disadvantage of electrically driven pump is the need for a servo or switching function for radio control & a need to monitor boiler water levels regularly

So I now have both Microcosm M5 and M8 pumps

** I found the Microcosm electric motor/speed reducer for the M5 very noisy and of questionable quality...Jin offered to replace it FOC, however my postage cost was greater than the purchase cost of a replacement in Australia....have also added an M4 bearing housing for the output shaft **

I have disguised the manual M8 pump body & housing ...it was used to provide my hydrostatic water boiler test, but can be used as a boiler water makeup
 
Derek   

[dosteam1]

The only real disadvantage I see with driving a boiler water makeup piston pump directly from the engine crank, is that pump displacement is directly proportional to the engine speed

So some use an external needle valve to maintain a preset pump volume that is also set to exceed the boiler relief valve pressure setting

So the upshot of such difficult external needle valve set points, the pump is working to boiler relief valve load and dumping a large quantity of water overboard or back to your boiler water feed tank whenever the engine is running

The disadvantage of electrically driven pump is the need for a servo or switching function for radio control & a need to monitor boiler water levels regularly

So I now have both Microcosm M5 and M8 pumps

** I found the Microcosm electric motor/speed reducer for the M5 very noisy and of questionable quality...Jin offered to replace it FOC, however my postage cost was greater than the purchase cost of a replacement in Australia....have also added an M4 bearing housing for the output shaft **

Thank you for pointing out the "external needle valve" suggestion, quick question would an adjustment screw work in the situation of an engine-powered feed pump to? Basically screwing the screw in would move the pump closer to the crank lowering the stroke length and also the amount of water it can take up for every rotation of the crank and screwing it out would have the opposite effect? Did you see any noticeable rpm drop with having the engine power the pump directly? Also where in the world did you find bearing 4mm pillow blocks? smallest I could find is 8mm. The last question is what oil do you guys use for your engine I read on another forum that motor oil was ok so I used 5w-30 to do a quick 15 second run on 5psi of compressed air, the engine seems very rev-happy I don't know if this is normal, as this is my first hobby grade steam engine.

[derekwarner_decoy]

The Microcosm M5 pump has a M4mm diameter output shaft......I have added the M4 shaft diameter s/s ZZ ball race in the pillow block are from.......SPD/Si ...they are from the US, they will supply on-line purchases for the same $ as the Australian Importer who do not necessarily stock the product

I found the loading on the speed reducer driving the pump eccentric was such that the final external bearing support was needed and eliminated pressure stroke eccentric off axis screaming/loading

So the eccentric sheave on the M5 Microsm piston pump is fixed at the machined 5 mm stroke........it is fixed and cannot be adjusted.......I have added a 22 Caliber brass shell case + a Microcosm M3 Plexiglass oiler

The recommended oil for the steam engine via the lubricator must be Steam Oil [Grade 460 appears fine]..it contains synthetic Fatty inclusions that do not breakdown at 100 + degrees C so maintains good lubricity with in the wet steam elements within the engine

Lubrication for external bearing journals etc .......Sewing machine oil [SAE 10?] is also totally acceptable.........whatever, do not  use WD40 or RP7 type sprays..........it degrades nitrile elastomers ........

Derek

PS....I am also using some SPD/Si 1/4" shaft size pillow blocks [same housing size] for the proposed paddle shaft drive 

[derekwarner_decoy]

Hullo Jurgen.....I am progressing on very slowly

Could you please confirm [with photographs] of the method of waterproofing or eliminating water from the splash of the wheels from migrating along the paddle shaft into the hull

[understood I could use an 0-ring in a simple housing, however am interested in other options]

I am moving the paddle shaft axis from above the crank axis  by 20mm to below the crank axis by 40mm [yes 60 total]

This then elevates the complete steam plant considerably [~~45mm] and so will be far more visible .... I will post a few images in my Saito Engine page

Derek