Infeed Systems for Moulders

A moulding manufacturer wants to set up a continuous infeed system for one of his machines. He gets tips and advice on what works and what doesn't. July 13, 2005

I'm setting a molder up to run fully jointed. Although I'm sure two men could feed it by hand, I'm considering installing an automatic infeed system. Something like a green chain coming off the gang rip where the molding strips could be graded as they feed into the molder. Our molder has a z-drive hopper feeding system, but I'm not convinced this will suffice. We'll be feeding small strips 1" x 1/2" x 12' long. I was wondering if anyone has a similar setup. If so, can you recommend a material handling system that would work for this application?

Forum Responses
(Solid Wood Machining Forum)
From Dave Rankin, forum technical advisor:
A couple of options to consider are a Lateral Feed Chain that will allow you a common possibility, and a Cantered Feed Roller. Both of these options will allow you to run over 200 feet per minute. There are many sources of these feed systems, both new and used.

From contributor T:
I would stick with the z-drive. I currently run three molders with three different types of feeders. The lateral chain feeder in my opinion is best suited for larger material than what your planning. The z-drive is a well built feeder that is easy to use and maintain. A couple things to note is that I had to modify the claw by removing the center tooth leaving only two teeth. Reason being, chip buildup in the teeth prevented the claw from gripping the next piece.

The other point is that if your worried about running at high speeds and not having it keep up, it does just fine up to about 160 fpm. The ratings are based on one foot long sticks, so anything over two foot doesn't need to account for the return travel of the arm so you can run as fast at the arm travels in the forward direction. Hope this info helps you out.

From the original questioner:
I have thought about using the z-drive, but here's what I'm up against. We've used the cart system before on longer runs and it worked out ok, but we've never run anything over 100 ft. per minute. I would think at speeds over 200 feet per minute would require two infeed guys allowing time to pull the material from the cart, discard the defective pieces, and put the best side up.

If these strips came directly from the gang rip and traveled laterally on a conveyor to the molder this would eliminate the need for the extra infeed person. I have even considered using a lateral conveyor along with the z-drive. Wouldn't it just be a matter of having the material drop from the conveyor into the z-drive hopper? This may be difficult to do with small 12' long strips. I'll be exclusively running one profile with this setup, so I'm looking for the best long term solution.

From contributor T:
A lateral chain feeder by itself will do the job. I tried combinations of different feeders trying to work together in my experience, and it was something I’ll never do again. Some of the advantages of the lateral chain is that they will go high speed, and you will be able to keep a large buffer built up on the table so the operator has time to defect.

Some disadvantages are their size; they use up a fair amount of floor space. Also, the distance between the feeder and the molder is usually a four foot bridge, which gives the little sticks too much time to get a mind of their own. The smallest piece I run on my chain feeder is 1-1/4" x 1". When I have to do smaller than that I use the rubber rollers on the feeder. Once the work piece catches up to the previous piece, the rollers will slip rather than apply too much pressure and break the small blanks.

I also keep my mill broke up into work cells where the ripping and defecting, and molding is done independent of one another. Previous experience has shown that setting up a production line from rough to finish depends too much on having everyone there to make it work.

From the original questioner:
I'll have a 50' x 80' work area dedicated to this production line. This workspace will consist of a gang rip saw, outfeed/infeed conveyor, molder, two auto strapping machines, and a separate defecting station. I can see negative aspects to a production line like this. Energy consumption is one. They base the monthly rate on maximum load for a fifteen minute time period. Gang rip, molder, and dust collection makes a meter spin fast.

However, I can see how material flow, inspecting, defecting, and so forth would go much smoother if the molder operator is spending his time scanning the strips rather than pulling pieces from a cart. It would definitely be less fatigue on the operator.