Sixis 101 House Mill

[Jo]

Dave it is not designing the pattern, we have done that (attached) it is my experience of using the brown stuff  Jason has been trying to convince me that working in white building wood is not the same as the green stuff he has generously given me.  I am going to start with the putting together the patterns for the BB1 gears to enable me to understand this material and work up to the tilting table design that I posted a few pages ago.

Phil: originally with the BCA I used large diameter dial gauges, you could them read to 0.001mm the standard glass scale are only to 0.01mm. I still notice that it takes a (relative) lot of movement on the BCA handle to get that smallest digit to increase. So for now DROs are on hold for Sexy.

Jo

[Jasonb]

When Jo said green stuff don't think she is talking about unseasoned wood, I have given her some Moisture Resistant MDF which will be ideal for the gear blanks and could also be glued up for the bracket.

Alibre does not put the draft angle on to the circular parts in a way that would allow the part line to go where I think it needs so its a bit of a long process drawing and then cutting 2degree triangles off.

I've seen that drawing somewhere before haven't I

[steamer]

Dave it is not designing the pattern, we have done that (attached) it is my experience of using the brown stuff  Jason has been trying to convince me that working in white building wood is not the same as the green stuff he has generously given me.  I am going to start with the putting together the patterns for the BB1 gears to enable me to understand this material and work up to the tilting table design that I posted a few pages ago.

Phil: originally with the BCA I used large diameter dial gauges, you could them read to 0.001mm the standard glass scale are only to 0.01mm. I still notice that it takes a (relative) lot of movement on the BCA handle to get that smallest digit to increase. So for now DROs are on hold for Sexy.

Jo

Yes...but having the pattern drawing in front of you makes decision making with the brown stuff easier

Looks like a layer cake to me.....You may want to consider a core print coming out the top of the table base....would save some hogging of material later. Maybe a 1" core?

Dave

[Jo]

  This is my first attempt at having my own castings done and pattern making. I want to start simply and work up to more complicated stuff at a later stage.

Jo

[steamer]

Well....it would actually make the pattern less complex.   Now I state this based on the fact that in the States, foundries that pour iron have round core stock in 1/8" increments.  So if you add a core print, the foundry could just drop in a premanufactured core during the molding process.

Here's a picture of one of my cylinder blocks with "core prints" which are in red.



The pattern would be rammed, and then removed, then just prior to closing it up...the cylindrical cores would be dropped into the impressions made by the "core prints"

Now this does have a draw back, depending on the foundry.   If the resulting section is thin, it can chill in the mold and be hard.   The foundryman can give you better advise on that than I, but I didn't have any problems machining my castings.

Dave

[Jasonb]

To be fair to Jo that was just a part done sketch to give her an idea of how I thought it needed to be split to enable it to be pulled from the sand. Yes it could be cored say 1" as the bore is 35mm which would reduce the risk of shrinkage in that area.

[steamer]

No Critisizm Jason....just an observation.    Your right about the shrinkage.

But some of this will be foundry specific...as well as gates and risers....so that's why I think it a good idea to bring a drawing of the pattern to the foundry first...and get some feedback from them

The foundry I used for instance much prefers that you use a match plate as they have quite a bit of automated equipment in their facility, and it simplifies the whole work flow....but I've heard of foundries that will work with loose patterns....so it depends....in any case, it will show that you care about a good casting if you involve them up front.

Additionally, thought should be given to the first cut....in what machine and with what tooling?.....it's hard to hang on to draft...if you look at my block casting...it was a *@&^*@^ to set up for the first cut...and this part seems doubly so.   Perhaps a chucking spigot somewhere?....maybe a boss to put a center in to support the other side with the tailstock?

That would allow a facing cut using a 4 jaw which will give you a nice flat surface to start with .......just thinking out loud.

Dave

[Mosey]

Jo,
The F1 manuals are 25-35 pages long, each, so I cannot email them as Steamer also mentioned. Maybe at some time I can put them on a cd. In the meantime, if there is some item you need to know about, I think I can scan it for you, don't hesitate to ask.
Mosey

[chucketn]

Mosey, if the manuals are in pdf format, could you compress them into a zip file?

Chuck

[steamer]

And when I say layer cake...I mean I see 3 distinct pieces...2 of which are similar.

The two "disks"

The center piece could have the core prints built into it, and these could project through one of the disks.

Make up your blanks from two halves...joined at the parting line with wood glue, but put a piece of newspaper in between...so you can seperate them later...and go somewhat easy on the glue, and bury a brass screw in there so you can work it as one piece, and it won't fall apart...until you want it to.
Add a couple of wood dowel pins to the blank too.  To maintain a register.

Dave

[Mosey]

Mosey, if the manuals are in pdf format, could you compress them into a zip file?

Chuck

No,no, they are paper! Remember that stuff, LOL!
Mosey

[Roger B]

 

[Jo]

  This all seems too difficult I will stick with the gears this time and see how it goes.

-----

So really that must the the end of Sexy's thread he has moved in and is performing  very nicely.

Back to engine building 

Jo

[pgp001]

Somehow I don't think we will have heard the last from him, he is male and living in your house after all.
Once he starts showing his bad habits, I am sure you will be telling us. 

I bet he's already leaving stuff lying around on the floor !!
Wait till you give him some coolant and he becomes incontinent 

Phil

[Mosey]

Male? A tiny Swiss mill that's a male! I can't believe it! Wait till it changes it's mind a few times, and gets moody, then we'll see, and, wants more accessories, and demands more attention.