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Scale-Master

Lola T-70 Mk III

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On 12/24/2019 at 5:52 PM, Scale-Master said:

Thanks guys!

 

I took a shot at growing some parts myself.  Here's a valve cover.  It's hard to capture the details in the clear resin in photos.  I plan to cast copies in opaque urethane resin.

J8fPjeu.jpg

Liking the valve cover that you have cast, Mark...... I have been considering casting a body shell in clear resin, and I am not quite sure if it is a good idea....... it would be a 1:24 Rolls-Royce Silver Cloud, showing the interior and engine visible through the clear resin body. The product that I would use is this one.... Pebeo Gedeo Crystal Resin, which I believe is a French product.

How did you find the clear resin to use?

David

$_32.jpg

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Mark mentioned that he "grew" the clear resin valve cover.  He uses the word "grow" to describe what others call "3D printing".  I believe that he "printed" (not cast) these covers. Probably using a UV-curable clear resin in a SLA printer. Or is it a "grower"?  :)

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Yes, Peter has the correct terminology. 

I use "printing" and "growing" to differentiate between decal art and 3D parts to avoid confusion since I do both for my clients.  The valve cover was grown/3D printed with U.V. cured resin.

Casting is yet one more process.

I personally don't care for the look of clear cast or molded bodies as the various wall thicknesses and other internal features make for a distracting uneasy to see through product.  It takes a lot of extra work to finish the inside surfaces too.  So I have not looked too much into clear casting resins.

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The alternator parts were grown by Fraxional, but I neglected to send one of the part files so the clear piece is the inner/center section that I grew rather than wait. 

k6IO1V3.jpg

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I made some design changes to the wheel centers and rather than wait for Fraxional to grow new ones for me I took a shot at it by doing a front first.  (My impatience; they have good turn-around times).  I can't get the quality that Fraxional does (at least at this time…) and so I had to spend a couple hours fine tuning it on the mill.  Not sure if this will be the final master or if I will go back to my original plan of having Fraxional grow these wheel parts.  Primer will help determine that path…

yjow0wR.jpg

pndQPZ4.jpg

Doesn't look too bad with my aluminum outer rim on it though.

bIKEiTj.jpg

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Thanks Trevor, yes they do very nice work.

 

I grew the masters of the Wilwood calipers I designed but was not able to get the outsides to look their best without sacrificing the details on the insides where the pads mount.

kgF1kBf.jpg

lyRhPXi.jpg

I machined and hand finished the insides to accept the pads and to fit together.

L5E1ydZ.jpg

Fronts on top, rears on the bottom.

6YO3Ups.jpg

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This is the inside of the valve cover master.  While I designed it with mounting features they filled in when the part was grown.  So I milled those features in by hand.

digG9rT.jpg

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I wasn't satisfied with the last wheel I grew so I redesigned a few parts of it and made a new one.  The front came out fine; it was the back side I didn't like.

It like the previous one required a good bit of post-machine work (it was designed to have that work done) and I think it is an improvement.

nJj7msh.jpg

eQXLHfE.jpg

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On 12/27/2019 at 3:04 AM, Scale-Master said:

I made some design changes to the wheel centers and rather than wait for Fraxional to grow new ones for me I took a shot at it by doing a front first.  (My impatience; they have good turn-around times).  I can't get the quality that Fraxional does (at least at this time…) and so I had to spend a couple hours fine tuning it on the mill.  Not sure if this will be the final master or if I will go back to my original plan of having Fraxional grow these wheel parts.  Primer will help determine that path…

yjow0wR.jpg

pndQPZ4.jpg

Doesn't look too bad with my aluminum outer rim on it though.

bIKEiTj.jpg

Your road wheel with the aluminium outer rim looks good, Mark...... thanks for the explanation regarding the clear casting, and clear resin 3D printing ( growing ).. which all makes sense now!

David

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The valve cover pattern is done and ready to have a mold made from it.

QE6sjoE.jpg

Same for the calipers.

36kuIFf.jpg

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Once in primer I still was not satisfied so I re-engineered the wheel to be three pieces instead of two.

This is the new spoke piece as it was grown.

TgUdFDP.jpg

4k6x27n.jpg

And then machined.

5jdh7M0.jpg

LjMQOV0.jpg

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This is the rear section of the new rim design; it still needs to be final machined.

0PZu4Ux.jpg

vrcGxSQ.jpg

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The U.V. resin is very hard and brittle.  That part did not survive the machining process.

I started growing a beefier part and realized I could probably machine one from scratch faster.

I was correct, made this from scratch and the printer is still running.

ZW6HGVq.jpg

FnGUcz7.jpg

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I grew a new alternator fan but the inside filled in, a common issue with this printer.

BQYokSE.jpg

So I machined it out.

AfsRMjh.jpg

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I had a bit of a setback when it turned out that the platinum based RTV I use primarily would not cure against the U.V. cured 3D resin from the printer.  Even after using the sealing materials that worked as barriers in the past, the molds were not curing and worse than the time loss was it making gooey messes on my patterns. That took many hours over several days to clean up.

I invested in some tin based RTV and that seems to be the right stuff for this resin. 

Here are the calipers and one pair of pads I'll use on the car.

2cqXrO5.jpg

GNEFGgz.jpg

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Mark,

Glad to see you back at it, sorry to hear about the bad luck.

The new parts look great.

Trevor

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Thank you Trevor. 

Set backs are to be expected now and again.  Figuring out how to work around them is just par for the course.

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8 hours ago, Scale-Master said:

Thank you Trevor. 

Set backs are to be expected now and again.  Figuring out how to work around them is just par for the course.

Your welcome. Yes they are, very true.

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These are the resin versions of the valve covers.
utTmP3a.jpg
With an internal mounting system to hold and align the magnets to the ones in the heads.
faAm8Jj.jpg
Uw4QgqS.jpg
7u8vI1a.jpg
 

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Thanks Trevor.  

 

I redesigned the rear wheel to be three pieces like the fronts and restyled the back of the spokes to match too.  This is the raw 3D grown/printed master before machining.

SAsBM3a.jpg

jHOWlIo.jpg

 

And after…

RNt6jy1.jpg

oNxNw3P.jpg

(The black marks are index points for making the mold.)

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