Re: [CAD_CAM_EDM_DRO] Re: Scraping

Hi All:
I've been listening in on the dovetail discussion with interest.
Here's how I have done them in the past.(no scraping required)
I mill the smaller bit first, regardless whether it is the male or the
female side.
The female gets a one-way tapered gib that is bolted in position before the
female dovetail is completed.
All the corners are generously relieved before I fit the dovetails.
All of the milling for each dovetail is done in one setup so that everything
stays as parallel as the machine will cut.
The finish cuts are done with a brand new cutter, taking less than a 0.010"
cut.
The smaller part gets a 0.002" stepdown at one end so it can be used as a
go-nogo gage and to ease the entry of the mating part while fitting.
If I need truly dead-nuts precision, I surface grind the dovetails, or I lap
them in with Clover compound and a soft brass lap.
I've made hundreds this way; the process flow is straightforward once you've
done it once, and the dovetails can be made to a very good level of
precision this way.
Cheers

Marcus

-----Original Message-----
From: Doug Harrison <prototype@...>
To: CAD_CAM_EDM_DRO@yahoogroups.com <CAD_CAM_EDM_DRO@yahoogroups.com>
Date: Friday, July 13, 2001 4:36 PM
Subject: Re: [CAD_CAM_EDM_DRO] Re: Scraping

>----- Original Message -----
>From: Chris Stratton <stratton@...>
>
>> Since scraping has come up, I'm wondering if anyone could comment on how
>one scrapes the inside-slanted surface of dovetails?
>
>Scraping dovetails often requires considerable practice. The scraper is
>usually smaller for getting into the corner. You also need a bevelled
>straightedge to do your markings properly. I did a B&S mill without one

and

>would not recommend it. The casting offered by Mike Morgan has a bevelled
>edge for this purpose.
>
>If I were building a slide from scratch I would probably use square or V
>ways as they are easier to construct. You can also avoid scraping one
>surface if you use Moglice to cast it in place.
>
>Doug