Project of the Month built by mirek111

Help Support Home Model Engine Machinist by donating using the link above or becoming a Supporting Member.
Home Model Engine Machinist > Building Them > Plans > LSx Engine w/ 1" bore

Thread Tools
Old 09-12-2016, 03:45 PM   #61
Join Date: Apr 2015
Location: Michigan
Posts: 33
Liked 28 Times on 15 Posts
Likes Given: 3


Alright folks! It's been a while and I wanted to post a few more pics and put a few manufacturing thoughts out there. I have been revising my engine block model to better match my desired manufacturing process. I am planning to leverage lost PLA investment casting such that I can print a 3D model of these parts and then cast them in aluminum. My goal is to post-process the casting using my manual machines (No CNC access for me).

The biggest feature that I have added is a set of ribs on the deck of the block. These positioning ribs help position the engine block flat when upside down. There may be some marginal benefit for 3D printing. These features will later be removed by machining process, but will provide a strong square base for initial machining operations. These initial operations are quite important as they will ensure that the top, bottom, front, and back are all square and perpendicular to each other. All other machining and drilling operations will depend on the block being square. The block is about 5.650" inches long, so it fits well inside a 6" machinist vice. If I had a 5" vise, I could mill the bottom, front, and back faces in one setup.

I am planning to 3D print setup tooling for machining the block as well. This too may not work the first attempt, but I believe that the surface finish is reasonable and this temporary tooling need not hold any true clamping force. As long as I keep these fixtures as positioning only, and clamp the block cleanly between the jaws, this could save a lot of time machining aluminum setup tools.

I am about to get my feet wet with the investment casting process! Here are some pics of the most recent block model. I first developed the engine block model as a "machined part" so to speak. Once I was happy with the finished product, I added material to generate a "net form" or as-cast model of the block. This included adding material anywhere I wanted to have a machined surface, closing drill holes, and adding enough material to the bottom end of the block to permit drilling and reaming of those features. It is fun to be able to draw and print parts that have undercuts. If the 3D printer can print them (but the part could not come out of a mold) investment casting can cast it. Lastly, I am planning to leverage the mains of the block as the runners from the main sprue when casting the part.

The block that is greenish in color is the latest version of my net form design printed in PLA. This was my first print with PLA and I did have issues with a portion of the model not sticking to the build plate properly. I have increased my model size by 101.8% to account for material shrinkage. It will be interesting to see how the model holds up once I am able to pour the first sample. I may expect some issues as I refine my abilities to cast these parts, but am looking forward to that step.

Click image for larger version

Name:	IMG_4270.jpg
Views:	430
Size:	79.9 KB
ID:	84081

Click image for larger version

Name:	IMG_4269.jpg
Views:	368
Size:	45.0 KB
ID:	84082

Click image for larger version

Name:	IMG_4267.jpg
Views:	365
Size:	42.2 KB
ID:	84083

bigmellon is offline  
btroxl Likes This 
Reply With Quote
Old 11-30-2016, 09:57 AM   #62
DayDreamer's Avatar
Join Date: Nov 2016
Location: Mission, Texas
Posts: 1

I'd love to see how this process works for the casting process as I've been thinking of using that to help produce a motorcycle engine that I've been wanting to design and build
DayDreamer is offline  
Reply With Quote

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Suitable boiler plans for a 1 1/2" bore Stationary Engine ned100 Boilers 22 11-03-2015 11:39 AM
Horizontal IC Engine 5/8" Bore cfellows A Work In Progress 79 02-23-2015 04:06 PM
Engine bore/stroke ratios MarkB General Engine Discussion 11 05-29-2014 01:01 PM
Boiler feed pump (cylinder bore v pump bore) question syrtismajor General Engine Discussion 2 09-28-2011 06:39 PM
Reaming a 1/8" bore to about 2 1/2" deep DickDastardly40 Tools 9 11-28-2008 08:38 AM

Newest Threads

- Top - Member List